Last data update: Oct 07, 2024. (Total: 47845 publications since 2009)
Records 1-26 (of 26 Records) |
Query Trace: D'Alessandro M[original query] |
---|
Using Public Feedback about the use of Elastomeric Half Mask Respirators to Inform a National Deployment Study within Health Settings
Haas EJ , Greenawald LA , Furek A , D'Alessandro MM . J Int Soc Respir Prot 12/28/2021 38 (2) 92-106 Reusable elastomeric half mask respirators (EHMRs) have been encouraged for use during conventional, contingency, and crisis capacity in healthcare delivery settings as an alternative to disposable N95 filtering facepiece respirators (FFRs). However, standard, operationalized guidelines for implementing EHMRs in healthcare and first responder settings are needed to facilitate such integration. Specifically, research is needed to identify and address specialized concerns in healthcare delivery settings beyond hospitals to understand the widespread barriers to EHMR use and how organizational culture can support or hinder EHMR adoption. The Strategic National Stockpile (SNS) requested support from the National Institute for Occupational Safety and Health (NIOSH) to develop its strategy to purchase and distribute EHMRs to interested health organizations. To support this SNS effort, NIOSH published a Federal Register Notice (FRN) to request formative input from the public on the nationwide distribution of EHMRs and provided the technical analysis of the responses. Twenty-two representatives from first responder organizations, healthcare and dental associations, manufacturers, higher education, medical/nursing societies, and a union provided comments for consideration. This feedback was qualitatively analyzed to identify themes among the comments. This paper discusses patterns that emerged in the feedback provided within the primary topics of perceived advantages and disadvantages of EHMRs and key considerations for a successful national deployment of EHMRs. This paper also discusses how the formative feedback received was critical to informing the SNS's strategy to purchase and deploy EHMRs for longitudinal demonstration projects with the goal to produce updated EHMR implementation guidelines and best practices. |
Fetal sex and risk of pregnancy-associated malaria in Plasmodium falciparum-endemic regions: a meta-analysis
Unger HW , Hadiprodjo AJ , Gutman JR , Briand V , Fievet N , Valea I , Tinto H , D'Alessandro U , Landis SH , Ter Kuile F , Ouma P , Oneko M , Mwapasa V , Slutsker L , Terlouw DJ , Kariuki S , Ayisi J , Nahlen B , Desai M , Madanitsa M , Kalilani-Phiri L , Ashorn P , Maleta K , Tshefu-Kitoto A , Mueller I , Stanisic D , Cates J , Van Eijk AM , Ome-Kaius M , Aitken EH , Rogerson SJ . Sci Rep 2023 13 (1) 10310 In areas of moderate to intense Plasmodium falciparum transmission, malaria in pregnancy remains a significant cause of low birth weight, stillbirth, and severe anaemia. Previously, fetal sex has been identified to modify the risks of maternal asthma, pre-eclampsia, and gestational diabetes. One study demonstrated increased risk of placental malaria in women carrying a female fetus. We investigated the association between fetal sex and malaria in pregnancy in 11 pregnancy studies conducted in sub-Saharan African countries and Papua New Guinea through meta-analysis using log binomial regression fitted to a random-effects model. Malaria infection during pregnancy and delivery was assessed using light microscopy, polymerase chain reaction, and histology. Five studies were observational studies and six were randomised controlled trials. Studies varied in terms of gravidity, gestational age at antenatal enrolment and bed net use. Presence of a female fetus was associated with malaria infection at enrolment by light microscopy (risk ratio 1.14 [95% confidence interval 1.04, 1.24]; P = 0.003; n = 11,729). Fetal sex did not associate with malaria infection when other time points or diagnostic methods were used. There is limited evidence that fetal sex influences the risk of malaria infection in pregnancy. |
Elastomeric Half Mask Respirators: An Alternative to Disposable Respirators and a Solution to Shortages during Public Health Emergencies
Greenawald LA , Haas EJ , D'Alessandro MM . J Int Soc Respir Prot 2021 38 (2) 74-91 During public health emergencies such as an influenza pandemic, disposable filtering facepiece respirator (FFR) shortages have a significant impact on the national response, affecting many types of workplaces that rely on respiratory protection. During the COVID-19 pandemic, severe FFR shortages led the CDC to publish strategies for optimizing the supply of N95 FFRs. These strategies included the extended use and limited reuse of FFRs, wearing decontaminated FFRs, wearing respirators that meet an international respirator standard, or wearing FFRs that were past their manufacturer-designated shelf life. An additional strategy to mitigate supply shortages that was highlighted during the COVID-19 pandemic was to wear reusable respirators, such as elastomeric half mask respirators (EHMRs), or powered air-purifying respirators, which can be cleaned, disinfected, and reused. A decade of nationwide initiatives to increase the utility of EHMRs in healthcare settings were realized during the COVID-19 pandemic as EHMRs became more well-known and were used in healthcare settings for respiratory protection. This expanded use of EHMRs led to an increase in federal procurement, research, guidance, and private sector research and development of innovative EHMR designs by manufacturers to respond to workers' needs for both respiratory protection and source control. This paper describes the role of reusable EHMRs before and during the COVID-19 pandemic, and reviews past and current research, to inform successful EHMR implementation in healthcare and first responder settings. |
Safety of single-dose primaquine as a Plasmodium falciparum gametocytocide: a systematic review and meta-analysis of individual patient data
Stepniewska K , Allen EN , Humphreys GS , Poirot E , Craig E , Kennon K , Yilma D , Bousema T , Guerin PJ , White NJ , Price RN , Raman J , Martensson A , Mwaiswelo RO , Bancone G , Bastiaens GJH , Bjorkman A , Brown JM , D'Alessandro U , Dicko AA , El-Sayed B , Elzaki SE , Eziefula AC , Gonçalves BP , Hamid MMA , Kaneko A , Kariuki S , Khan W , Kwambai TK , Ley B , Ngasala BE , Nosten F , Okebe J , Samuels AM , Smit MR , Stone WJR , Sutanto I , Ter Kuile F , Tine RC , Tiono AB , Drakeley CJ , Gosling R , Stergachis A , Barnes KI , Chen I . BMC Med 2022 20 (1) 350 BACKGROUND: In 2012, the World Health Organization (WHO) recommended single low-dose (SLD, 0.25 mg/kg) primaquine to be added as a Plasmodium (P.) falciparum gametocytocide to artemisinin-based combination therapy (ACT) without glucose-6-phosphate dehydrogenase (G6PD) testing, to accelerate malaria elimination efforts and avoid the spread of artemisinin resistance. Uptake of this recommendation has been relatively slow primarily due to safety concerns. METHODS: A systematic review and individual patient data (IPD) meta-analysis of single-dose (SD) primaquine studies for P. falciparum malaria were performed. Absolute and fractional changes in haemoglobin concentration within a week and adverse effects within 28 days of treatment initiation were characterised and compared between primaquine and no primaquine arms using random intercept models. RESULTS: Data comprised 20 studies that enrolled 6406 participants, of whom 5129 (80.1%) had received a single target dose of primaquine ranging between 0.0625 and 0.75 mg/kg. There was no effect of primaquine in G6PD-normal participants on haemoglobin concentrations. However, among 194 G6PD-deficient African participants, a 0.25 mg/kg primaquine target dose resulted in an additional 0.53 g/dL (95% CI 0.17-0.89) reduction in haemoglobin concentration by day 7, with a 0.27 (95% CI 0.19-0.34) g/dL haemoglobin drop estimated for every 0.1 mg/kg increase in primaquine dose. Baseline haemoglobin, young age, and hyperparasitaemia were the main determinants of becoming anaemic (Hb < 10 g/dL), with the nadir observed on ACT day 2 or 3, regardless of G6PD status and exposure to primaquine. Time to recovery from anaemia took longer in young children and those with baseline anaemia or hyperparasitaemia. Serious adverse haematological events after primaquine were few (9/3, 113, 0.3%) and transitory. One blood transfusion was reported in the primaquine arms, and there were no primaquine-related deaths. In controlled studies, the proportions with either haematological or any serious adverse event were similar between primaquine and no primaquine arms. CONCLUSIONS: Our results support the WHO recommendation to use 0.25 mg/kg of primaquine as a P. falciparum gametocytocide, including in G6PD-deficient individuals. Although primaquine is associated with a transient reduction in haemoglobin levels in G6PD-deficient individuals, haemoglobin levels at clinical presentation are the major determinants of anaemia in these patients. TRIAL REGISTRATION: PROSPERO, CRD42019128185. |
Plasma levels of carboxylic acids are markers of early kidney dysfunction in young people with type 1 diabetes
Vigers T , Vinovskis C , Li LP , Prasad P , Heerspink H , D'Alessandro A , Reisz JA , Piani F , Cherney DZ , van Raalte DH , Nadeau KJ , Pavkov ME , Nelson RG , Pyle L , Bjornstad P . Pediatr Nephrol 2022 38 (1) 193-202 BACKGROUND: We compared plasma metabolites of amino acid oxidation and the tricarboxylic acid (TCA) cycle in youth with and without type 1 diabetes mellitus (T1DM) and related the metabolites to glomerular filtration rate (GFR), renal plasma flow (RPF), and albuminuria. Metabolites associated with impaired kidney function may warrant future study as potential biomarkers or even future interventions to improve kidney bioenergetics. METHODS: Metabolomic profiling of fasting plasma samples using a targeted panel of 644 metabolites and an untargeted panel of 19,777 metabolites was performed in 50 youth with T1DM ≤ 10 years and 20 controls. GFR and RPF were ascertained by iohexol and p-aminohippurate clearance, and albuminuria calculated as urine albumin to creatinine ratio. Sparse partial least squares discriminant analysis and moderated t tests were used to identify metabolites associated with GFR and RPF. RESULTS: Adolescents with and without T1DM were similar in age (16.1 ± 3.0 vs. 16.1 ± 2.9 years) and BMI (23.4 ± 5.1 vs. 22.7 ± 3.7 kg/m(2)), but those with T1DM had higher GFR (189 ± 40 vs. 136 ± 22 ml/min) and RPF (820 ± 125 vs. 615 ± 65 ml/min). Metabolites of amino acid oxidation and the TCA cycle were significantly lower in adolescents with T1DM vs. controls, and the measured metabolites were able to discriminate diabetes status with an AUC of 0.82 (95% CI: 0.71, 0.93) and error rate of 0.21. Lower glycine (r:-0.33, q = 0.01), histidine (r:-0.45, q < 0.001), methionine (r: -0.29, q = 0.02), phenylalanine (r: -0.29, q = 0.01), serine (r: -0.42, q < 0.001), threonine (r: -0.28, q = 0.02), citrate (r: -0.35, q = 0.003), fumarate (r: -0.24, q = 0.04), and malate (r: -0.29, q = 0.02) correlated with higher GFR. Lower glycine (r: -0.28, q = 0.04), phenylalanine (r:-0.3, q = 0.03), fumarate (r: -0.29, q = 0.04), and malate (r: -0.5, q < 0.001) correlated with higher RPF. Lower histidine (r: -0.28, q = 0.02) was correlated with higher mean ACR. CONCLUSIONS: In conclusion, adolescents with relatively short T1DM duration exhibited lower plasma levels of carboxylic acids that associated with hyperfiltration and hyperperfusion. TRIAL REGISTRATION: ClinicalTrials.gov NCT03618420 and NCT03584217 A higher resolution version of the Graphical abstract is available as Supplementary information. |
Applying the CDC Science Impact Framework to the results of the National Institute for Occupational Safety and Health and the Bureau of Labor Statistics 2001 Survey of Respirator Use and Practices
Yoon N , Ari M , Yorio P , Iskander J , D'Alessandro M . J Occup Environ Hyg 2022 19 (6) 1-31 During 2001-2002, the National Institute for Occupational Safety and Health (NIOSH), at the United States Centers for Disease Control and Prevention, collaborated with the Bureau of Labor Statistics (BLS) at the United States Department of Labor to conduct a voluntary survey of U.S. employers regarding the use of respiratory protective devices. In 2003, the survey results were jointly published by NIOSH and BLS. This study highlights and evaluates the scientific impact of the 2001-2002 survey by using Science Impact Framework that provides a historical tracking method with five domains of influence. The authors conducted interviews with original project management as well as a thorough document review and qualitative content analysis of published papers, books, presentations, and other relevant print media. A semi-structured and cross-vetted coding was applied across the five domains: Disseminating Science, Creating Awareness, Catalyzing Action, Effecting Change, and Shaping the Future. The 2001-2002 survey findings greatly enhanced understanding and awareness of respirator use in occupational settings within the United States. It also led to similar surveys in other countries, regulatory initiatives by the Occupational Safety and Health Administration and Mine Safety and Health Administration, and ultimately to a renewed partnership between NIOSH and BLS to collect contemporary estimates of respirator use in the workplace within the United States. |
Effective coordination, collaboration, communication, and partnering are needed to close the gaps for occupational PFAS exposure
Moore SM , Brown C , Kiederer M , Calkins MM , Burgess JL , D'Alessandro M , Davis R , Fenton SE , Morrison P , Reh CM . Am J Ind Med 2022 66 (5) 351-352 Over the past few decades, there has been a growing concern over the health effects associated with per- and polyfluoroalkyl substances (PFAS) exposure especially among worker populations. High levels of PFAS exposure have been linked to various health outcomes including cancer and increased cholesterol levels.1 Existing research on occupational PFAS exposure is limited to only a few industries. Given this, the focus of the American Journal of Industrial Medicine's special issue on occupational PFAS exposures is to review current knowledge of occupational exposures to PFAS; identify newer, emerging, or unstudied sources of exposure; assess gaps in present understanding of their occupational use and hazards; and outline the needs for future research and worker protection. This special issue will help advance the scientific community's understanding of PFAS and aid current and future research projects. However, there are additional critical drivers to the success of reducing occupational exposures to PFAS which need to be addressed. These critical drivers are effective coordination, collaboration, communication, and partnerships. |
Respiratory Protection in a Time of Crisis: NIOSH Testing of International Respiratory Protective Devices for Emergency Use.
Andrews AS , Powers JR Jr , Cichowicz JK , Coffey CC , Fries ML , Yorio PL , D'Alessandro MM . Health Secur 2021 19 (4) 379-385 National Institute for Occupational Safety and Health (NIOSH)-approved respirators are required by the Occupational Safety and Health Administration (OSHA) when personal respiratory protection is used in US occupational settings. During the COVID-19 pandemic, the demand for NIOSH-approved N95 filtering facepiece respirators overwhelmed the available supply. To supplement the national inventory of N95 respirators, contingency and crisis capacity strategies were implemented and incorporated a component that endorsed the use of non-NIOSH-approved respiratory protective devices that conformed to select international standards. The development and execution of this strategy required the collaborative effort of numerous agencies. The Food and Drug Administration temporarily authorized non-NIOSH-approved international respiratory protective devices through an emergency use authorization, OSHA relaxed their enforcement guidance concerning their use in US workplaces, and NIOSH initiated a supplemental performance assessment process to verify the quality of international devices. NIOSH testing revealed that many of the non-NIOSH-approved respiratory protective devices had filtration efficiencies below 95% and substantial inconsistencies in filtration performance. This article reports the results of the NIOSH testing to date and discusses how it has contributed to continuous improvement of the crisis strategy of temporarily permitting the use of non-NIOSH-approved respirators in US occupational settings during the COVID-19 pandemic. |
The risk of Plasmodium vivax parasitaemia after P. falciparum malaria: An individual patient data meta-analysis from the WorldWide Antimalarial Resistance Network
Hossain MS , Commons RJ , Douglas NM , Thriemer K , Alemayehu BH , Amaratunga C , Anvikar AR , Ashley EA , Asih PBS , Carrara VI , Lon C , D'Alessandro U , Davis TME , Dondorp AM , Edstein MD , Fairhurst RM , Ferreira MU , Hwang J , Janssens B , Karunajeewa H , Kiechel JR , Ladeia-Andrade S , Laman M , Mayxay M , McGready R , Moore BR , Mueller I , Newton PN , Thuy-Nhien NT , Noedl H , Nosten F , Phyo AP , Poespoprodjo JR , Saunders DL , Smithuis F , Spring MD , Stepniewska K , Suon S , Suputtamongkol Y , Syafruddin D , Tran HT , Valecha N , Van Herp M , Van Vugt M , White NJ , Guerin PJ , Simpson JA , Price RN . PLoS Med 2020 17 (11) e1003393 BACKGROUND: There is a high risk of Plasmodium vivax parasitaemia following treatment of falciparum malaria. Our study aimed to quantify this risk and the associated determinants using an individual patient data meta-analysis in order to identify populations in which a policy of universal radical cure, combining artemisinin-based combination therapy (ACT) with a hypnozoitocidal antimalarial drug, would be beneficial. METHODS AND FINDINGS: A systematic review of Medline, Embase, Web of Science, and the Cochrane Database of Systematic Reviews identified efficacy studies of uncomplicated falciparum malaria treated with ACT that were undertaken in regions coendemic for P. vivax between 1 January 1960 and 5 January 2018. Data from eligible studies were pooled using standardised methodology. The risk of P. vivax parasitaemia at days 42 and 63 and associated risk factors were investigated by multivariable Cox regression analyses. Study quality was assessed using a tool developed by the Joanna Briggs Institute. The study was registered in the International Prospective Register of Systematic Reviews (PROSPERO: CRD42018097400). In total, 42 studies enrolling 15,341 patients were included in the analysis, including 30 randomised controlled trials and 12 cohort studies. Overall, 14,146 (92.2%) patients had P. falciparum monoinfection and 1,195 (7.8%) mixed infection with P. falciparum and P. vivax. The median age was 17.0 years (interquartile range [IQR] = 9.0-29.0 years; range = 0-80 years), with 1,584 (10.3%) patients younger than 5 years. 2,711 (17.7%) patients were treated with artemether-lumefantrine (AL, 13 studies), 651 (4.2%) with artesunate-amodiaquine (AA, 6 studies), 7,340 (47.8%) with artesunate-mefloquine (AM, 25 studies), and 4,639 (30.2%) with dihydroartemisinin-piperaquine (DP, 16 studies). 14,537 patients (94.8%) were enrolled from the Asia-Pacific region, 684 (4.5%) from the Americas, and 120 (0.8%) from Africa. At day 42, the cumulative risk of vivax parasitaemia following treatment of P. falciparum was 31.1% (95% CI 28.9-33.4) after AL, 14.1% (95% CI 10.8-18.3) after AA, 7.4% (95% CI 6.7-8.1) after AM, and 4.5% (95% CI 3.9-5.3) after DP. By day 63, the risks had risen to 39.9% (95% CI 36.6-43.3), 42.4% (95% CI 34.7-51.2), 22.8% (95% CI 21.2-24.4), and 12.8% (95% CI 11.4-14.5), respectively. In multivariable analyses, the highest rate of P. vivax parasitaemia over 42 days of follow-up was in patients residing in areas of short relapse periodicity (adjusted hazard ratio [AHR] = 6.2, 95% CI 2.0-19.5; p = 0.002); patients treated with AL (AHR = 6.2, 95% CI 4.6-8.5; p < 0.001), AA (AHR = 2.3, 95% CI 1.4-3.7; p = 0.001), or AM (AHR = 1.4, 95% CI 1.0-1.9; p = 0.028) compared with DP; and patients who did not clear their initial parasitaemia within 2 days (AHR = 1.8, 95% CI 1.4-2.3; p < 0.001). The analysis was limited by heterogeneity between study populations and lack of data from very low transmission settings. Study quality was high. CONCLUSIONS: In this meta-analysis, we found a high risk of P. vivax parasitaemia after treatment of P. falciparum malaria that varied significantly between studies. These P. vivax infections are likely attributable to relapses that could be prevented with radical cure including a hypnozoitocidal agent; however, the benefits of such a novel strategy will vary considerably between geographical areas. |
Efficacy of single dose primaquine with artemisinin combination therapy on P. falciparum gametocytes and transmission: A WWARN individual patient meta-analysis
Stepniewska K , Humphreys GS , Gonçalves BP , Craig E , Gosling R , Guerin PJ , Price RN , Barnes KI , Raman J , Smit MR , D'Alessandro U , Stone WJR , Bjorkman A , Samuels AM , Arroyo-Arroyo MI , Bastiaens GJH , Brown JM , Dicko A , El-Sayed BB , Elzaki SG , Eziefula AC , Kariuki S , Kwambai TK , Maestre AE , Martensson A , Mosha D , Mwaiswelo RO , Ngasala BE , Okebe J , Roh ME , Sawa P , Tiono AB , Chen I , Drakeley CJ , Bousema T . J Infect Dis 2020 225 (7) 1215-1226 BACKGROUND: Since the World Health Organization recommended single low-dose (0.25mg/kg) primaquine (PQ) in combination with artemisinin-based combination therapies (ACTs) in areas of low transmission or artemisinin-resistant P. falciparum, several single-site studies have been conducted to assess its efficacy. METHODS: An individual patient meta-analysis to assess the gametocytocidal and transmission-blocking efficacy of PQ used in combination with different ACTs was conducted. Random effects logistic regression was used to quantify PQ effect on (i) gametocyte carriage in the first two weeks post-treatment; (ii) the probability of infecting at least one mosquito or of a mosquito becoming infected. RESULTS: In 2,574 participants from fourteen studies, PQ reduced PCR-determined gametocyte carriage on days 7 and 14, most apparently in patients presenting with gametocytaemia on day 0 (Odds Ratio (OR)=0.22; 95%CI 0.17-0.28 and OR=0.12; 95%CI 0.08-0.16, respectively). The rate of decline in gametocyte carriage was faster when PQ was combined with artemether-lumefantrine (AL) compared to dihydroartemisinin-piperaquine (DP) (p=0.010 for day 7). Addition of 0.25mg/kg PQ was associated with near complete prevention of transmission to mosquitoes. CONCLUSION: Primaquine's transmission-blocking effects are achieved with 0.25 mg/kg PQ. Gametocyte persistence and infectivity are lower when PQ is combined with AL compared to DP. |
Strategies for Optimizing the Supply of N95 Filtering Facepiece Respirators During the Coronavirus Disease 2019 (COVID-19) Pandemic.
de Perio MA , Dowell CH , Delaney LJ , Radonovich LJ , Kuhar D , Gupta N , Patel A , Pillai SK , D'Alessandro M . Disaster Med Public Health Prep 2020 14 (5) 1-23 N95 respirators are the personal protective equipment most often used to control exposures to infections transmitted via the airborne route. Supplies of N95 respirators can become depleted during pandemics or when otherwise in high demand. In this paper, we offer strategies for optimizing supplies of N95 respirators in healthcare settings while maximizing the level of protection offered to healthcare personnel when there is limited supply in the United States during the Coronavirus Disease 2019 (COVID-19) pandemic. The strategies are intended for use by professionals who manage respiratory protection programs, occupational health services, and infection prevention programs in healthcare facilities to protect healthcare personnel from job-related risks of exposure to infectious respiratory illnesses. Consultation with federal, state, and local public health officials is also important. We use the framework of surge capacity and the occupational health and safety hierarchy of controls approach to discuss specific engineering control, administrative control, and personal protective equipment measures that may help in optimizing N95 respirator supplies. |
Association between the proportion of Plasmodium falciparum and Plasmodium vivax infections detected by passive surveillance and the magnitude of the asymptomatic reservoir in the community: a pooled analysis of paired health facility and community data
Stresman G , Sepulveda N , Fornace K , Grignard L , Mwesigwa J , Achan J , Miller J , Bridges DJ , Eisele TP , Mosha J , Lorenzo PJ , Macalinao ML , Espino FE , Tadesse F , Stevenson JC , Quispe AM , Siqueira A , Lacerda M , Yeung S , Sovannaroth S , Pothin E , Gallay J , Hamre KE , Young A , Lemoine JF , Chang MA , Phommasone K , Mayxay M , Landier J , Parker DM , Von Seidlein L , Nosten F , Delmas G , Dondorp A , Cameron E , Battle K , Bousema T , Gething P , D'Alessandro U , Drakeley C . Lancet Infect Dis 2020 20 (8) 953-963 BACKGROUND: Passively collected malaria case data are the foundation for public health decision making. However, because of population-level immunity, infections might not always be sufficiently symptomatic to prompt individuals to seek care. Understanding the proportion of all Plasmodium spp infections expected to be detected by the health system becomes particularly paramount in elimination settings. The aim of this study was to determine the association between the proportion of infections detected and transmission intensity for Plasmodium falciparum and Plasmodium vivax in several global endemic settings. METHODS: The proportion of infections detected in routine malaria data, P(Detect), was derived from paired household cross-sectional survey and routinely collected malaria data within health facilities. P(Detect) was estimated using a Bayesian model in 431 clusters spanning the Americas, Africa, and Asia. The association between P(Detect) and malaria prevalence was assessed using log-linear regression models. Changes in P(Detect) over time were evaluated using data from 13 timepoints over 2 years from The Gambia. FINDINGS: The median estimated P(Detect) across all clusters was 12.5% (IQR 5.3-25.0) for P falciparum and 10.1% (5.0-18.3) for P vivax and decreased as the estimated log-PCR community prevalence increased (adjusted odds ratio [OR] for P falciparum 0.63, 95% CI 0.57-0.69; adjusted OR for P vivax 0.52, 0.47-0.57). Factors associated with increasing P(Detect) included smaller catchment population size, high transmission season, improved care-seeking behaviour by infected individuals, and recent increases (within the previous year) in transmission intensity. INTERPRETATION: The proportion of all infections detected within health systems increases once transmission intensity is sufficiently low. The likely explanation for P falciparum is that reduced exposure to infection leads to lower levels of protective immunity in the population, increasing the likelihood that infected individuals will become symptomatic and seek care. These factors might also be true for P vivax but a better understanding of the transmission biology is needed to attribute likely reasons for the observed trend. In low transmission and pre-elimination settings, enhancing access to care and improvements in care-seeking behaviour of infected individuals will lead to an increased proportion of infections detected in the community and might contribute to accelerating the interruption of transmission. FUNDING: Wellcome Trust. |
First trimester use of artemisinin-based combination therapy and the risk of low birth weight and small for gestational age
Augusto O , Stergachis A , Dellicour S , Tinto H , Vala A , Ruperez M , Macete E , Nakanabo-Diallo S , Kazienga A , Valea I , d'Alessandro U , Ter Kuile FO , Calip GS , Ouma P , Desai M , Sevene E . Malar J 2020 19 (1) 144 BACKGROUND: While there is increasing evidence on the safety of artemisinin-based combination therapy (ACT) for the case management of malaria in early pregnancy, little is known about the association between exposure to ACT during the first trimester and the effect on fetal growth. METHODS: Data were analysed from prospective studies of pregnant women enrolled in Mozambique, Burkina Faso and Kenya designed to determine the association between anti-malarial drug exposure in the first trimester and pregnancy outcomes, including low birth weight (LBW) and small for gestational age (SGA). Exposure to anti-malarial drugs was ascertained retrospectively by record linkage using a combination of data collected from antenatal and adult outpatient clinic registries, prescription records and self-reported medication usage by the women. Site-level data synthesis (fixed effects and random effects) was conducted as well as individual-level analysis (fixed effects by site). RESULTS: Overall, 1915 newborns were included with 92 and 26 exposed to ACT (artemether-lumefantrine) and quinine, respectively. In Burkina Faso, Mozambique and Kenya at recruitment, the mean age (standard deviation) was 27.1 (6.6), 24.2 (6.2) and 25.7 (6.5) years, and the mean gestational age was 24.0 (6.2), 21.2 (5.7) and 17.9 (10.2) weeks, respectively. The LBW prevalence among newborns born to women exposed to ACT and quinine (QNN) during the first trimester was 10/92 (10.9%) and 7/26 (26.9%), respectively, compared to 9.5% (171/1797) among women unexposed to any anti-malarials during pregnancy. Compared to those unexposed to anti-malarials, ACT and QNN exposed women had the pooled LBW prevalence ratio (PR) of 1.13 (95% confidence interval (CI) 0.62-2.05, p-value 0.700) and 2.03 (95% CI 1.09-3.78, p-value 0.027), respectively. Compared to those unexposed to anti-malarials ACT and QNN-exposed women had the pooled SGA PR of 0.85 (95% CI 0.50-1.44, p-value 0.543) and 1.41 (95% CI 0.71-2.77, p-value 0.322), respectively. Whereas compared to ACT-exposed, the QNN-exposed had a PR of 2.14 (95% CI 0.78-5.89, p-value 0.142) for LBW and 8.60 (95% CI 1.29-57.6, p-value 0.027) for SGA. The level of between sites heterogeneity was moderate to high. CONCLUSION: ACT exposure during the first trimester was not associated with an increased occurrence of LBW or SGA. However, the data suggest a higher prevalence of LBW and SGA for children born to QNN-exposed pregnancies. The findings support the use of ACT (artemether-lumefantrine) for the treatment of uncomplicated malaria during the first trimester of pregnancy. |
The haematological consequences of Plasmodium vivax malaria after chloroquine treatment with and without primaquine: a WorldWide Antimalarial Resistance Network systematic review and individual patient data meta-analysis.
Commons RJ , Simpson JA , Thriemer K , Chu CS , Douglas NM , Abreha T , Alemu SG , Anez A , Anstey NM , Aseffa A , Assefa A , Awab GR , Baird JK , Barber BE , Borghini-Fuhrer I , D'Alessandro U , Dahal P , Daher A , de Vries PJ , Erhart A , Gomes MSM , Grigg MJ , Hwang J , Kager PA , Ketema T , Khan WA , Lacerda MVG , Leslie T , Ley B , Lidia K , Monteiro WM , Pereira DB , Phan GT , Phyo AP , Rowland M , Saravu K , Sibley CH , Siqueira AM , Stepniewska K , Taylor WRJ , Thwaites G , Tran BQ , Hien TT , Vieira JLF , Wangchuk S , Watson J , William T , Woodrow CJ , Nosten F , Guerin PJ , White NJ , Price RN . BMC Med 2019 17 (1) 151 BACKGROUND: Malaria causes a reduction in haemoglobin that is compounded by primaquine, particularly in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency. The aim of this study was to determine the relative contributions to red cell loss of malaria and primaquine in patients with uncomplicated Plasmodium vivax. METHODS: A systematic review identified P. vivax efficacy studies of chloroquine with or without primaquine published between January 2000 and March 2017. Individual patient data were pooled using standardised methodology, and the haematological response versus time was quantified using a multivariable linear mixed effects model with non-linear terms for time. Mean differences in haemoglobin between treatment groups at day of nadir and day 42 were estimated from this model. RESULTS: In total, 3421 patients from 29 studies were included: 1692 (49.5%) with normal G6PD status, 1701 (49.7%) with unknown status and 28 (0.8%) deficient or borderline individuals. Of 1975 patients treated with chloroquine alone, the mean haemoglobin fell from 12.22 g/dL [95% CI 11.93, 12.50] on day 0 to a nadir of 11.64 g/dL [11.36, 11.93] on day 2, before rising to 12.88 g/dL [12.60, 13.17] on day 42. In comparison to chloroquine alone, the mean haemoglobin in 1446 patients treated with chloroquine plus primaquine was - 0.13 g/dL [- 0.27, 0.01] lower at day of nadir (p = 0.072), but 0.49 g/dL [0.28, 0.69] higher by day 42 (p < 0.001). On day 42, patients with recurrent parasitaemia had a mean haemoglobin concentration - 0.72 g/dL [- 0.90, - 0.54] lower than patients without recurrence (p < 0.001). Seven days after starting primaquine, G6PD normal patients had a 0.3% (1/389) risk of clinically significant haemolysis (fall in haemoglobin > 25% to < 7 g/dL) and a 1% (4/389) risk of a fall in haemoglobin > 5 g/dL. CONCLUSIONS: Primaquine has the potential to reduce malaria-related anaemia at day 42 and beyond by preventing recurrent parasitaemia. Its widespread implementation will require accurate diagnosis of G6PD deficiency to reduce the risk of drug-induced haemolysis in vulnerable individuals. TRIAL REGISTRATION: This trial was registered with PROSPERO: CRD42016053312. The date of the first registration was 23 December 2016. |
The effect of chloroquine dose and primaquine on Plasmodium vivax recurrence: a WorldWide Antimalarial Resistance Network systematic review and individual patient pooled meta-analysis
Commons RJ , Simpson JA , Thriemer K , Humphreys GS , Abreha T , Alemu SG , Anez A , Anstey NM , Awab GR , Baird JK , Barber BE , Borghini-Fuhrer I , Chu CS , D'Alessandro U , Dahal P , Daher A , de Vries PJ , Erhart A , Gomes MSM , Gonzalez-Ceron L , Grigg MJ , Heidari A , Hwang J , Kager PA , Ketema T , Khan WA , Lacerda MVG , Leslie T , Ley B , Lidia K , Monteiro WM , Nosten F , Pereira DB , Phan GT , Phyo AP , Rowland M , Saravu K , Sibley CH , Siqueira AM , Stepniewska K , Sutanto I , Taylor WRJ , Thwaites G , Tran BQ , Tran HT , Valecha N , Vieira JLF , Wangchuk S , William T , Woodrow CJ , Zuluaga-Idarraga L , Guerin PJ , White NJ , Price RN . Lancet Infect Dis 2018 18 (9) 1025-1034 BACKGROUND: Chloroquine remains the mainstay of treatment for Plasmodium vivax malaria despite increasing reports of treatment failure. We did a systematic review and meta-analysis to investigate the effect of chloroquine dose and the addition of primaquine on the risk of recurrent vivax malaria across different settings. METHODS: A systematic review done in MEDLINE, Web of Science, Embase, and Cochrane Database of Systematic Reviews identified P vivax clinical trials published between Jan 1, 2000, and March 22, 2017. Principal investigators were invited to share individual patient data, which were pooled using standardised methods. Cox regression analyses with random effects for study site were used to investigate the roles of chloroquine dose and primaquine use on rate of recurrence between day 7 and day 42 (primary outcome). The review protocol is registered in PROSPERO, number CRD42016053310. FINDINGS: Of 134 identified chloroquine studies, 37 studies (from 17 countries) and 5240 patients were included. 2990 patients were treated with chloroquine alone, of whom 1041 (34.8%) received a dose below the target 25 mg/kg. The risk of recurrence was 32.4% (95% CI 29.8-35.1) by day 42. After controlling for confounders, a 5 mg/kg higher chloroquine dose reduced the rate of recurrence overall (adjusted hazard ratio [AHR] 0.82, 95% CI 0.69-0.97; p=0.021) and in children younger than 5 years (0.59, 0.41-0.86; p=0.0058). Adding primaquine reduced the risk of recurrence to 4.9% (95% CI 3.1-7.7) by day 42, which is lower than with chloroquine alone (AHR 0.10, 0.05-0.17; p<0.0001). INTERPRETATION: Chloroquine is commonly under-dosed in the treatment of vivax malaria. Increasing the recommended dose to 30 mg/kg in children younger than 5 years could reduce substantially the risk of early recurrence when primaquine is not given. Radical cure with primaquine was highly effective in preventing early recurrence and may also improve blood schizontocidal efficacy against chloroquine-resistant P vivax. FUNDING: Wellcome Trust, Australian National Health and Medical Research Council, and Bill & Melinda Gates Foundation. |
Treatment of uncomplicated and severe malaria during pregnancy
D'Alessandro U , Hill J , Tarning J , Pell C , Webster J , Gutman J , Sevene E . Lancet Infect Dis 2018 18 (4) e133-e146 Over the past 10 years, the available evidence on the treatment of malaria during pregnancy has increased substantially. Owing to their relative ease of use, good sensitivity and specificity, histidine rich protein 2 based rapid diagnostic tests are appropriate for symptomatic pregnant women; however, such tests are less appropriate for systematic screening because they will not detect an important proportion of infections among asymptomatic women. The effect of pregnancy on the pharmacokinetics of antimalarial drugs varies greatly between studies and class of antimalarial drugs, emphasising the need for prospective studies in pregnant and non-pregnant women. For the treatment of malaria during the first trimester, international guidelines are being reviewed by WHO. For the second and third trimester of pregnancy, results from several trials have confirmed that artemisinin-based combination treatments are safe and efficacious, although tolerability and efficacy might vary by treatment. It is now essential to translate such evidence into policies and clinical practice that benefit pregnant women in countries where malaria is endemic. Access to parasitological diagnosis or appropriate antimalarial treatment remains low in many countries and regions. Therefore, there is a pressing need for research to identify quality improvement interventions targeting pregnant women and health providers. In addition, efficient and practical systems for pharmacovigilance are needed to further expand knowledge on the safety of antimalarial drugs, particularly in the first trimester of pregnancy. |
Malaria, malnutrition, and birthweight: A meta-analysis using individual participant data
Cates JE , Unger HW , Briand V , Fievet N , Valea I , Tinto H , D'Alessandro U , Landis SH , Adu-Afarwuah S , Dewey KG , Ter Kuile FO , Desai M , Dellicour S , Ouma P , Gutman J , Oneko M , Slutsker L , Terlouw DJ , Kariuki S , Ayisi J , Madanitsa M , Mwapasa V , Ashorn P , Maleta K , Mueller I , Stanisic D , Schmiegelow C , Lusingu JPA , van Eijk AM , Bauserman M , Adair L , Cole SR , Westreich D , Meshnick S , Rogerson S . PLoS Med 2017 14 (8) e1002373 BACKGROUND: Four studies previously indicated that the effect of malaria infection during pregnancy on the risk of low birthweight (LBW; <2,500 g) may depend upon maternal nutritional status. We investigated this dependence further using a large, diverse study population. METHODS AND FINDINGS: We evaluated the interaction between maternal malaria infection and maternal anthropometric status on the risk of LBW using pooled data from 14,633 pregnancies from 13 studies (6 cohort studies and 7 randomized controlled trials) conducted in Africa and the Western Pacific from 1996-2015. Studies were identified by the Maternal Malaria and Malnutrition (M3) initiative using a convenience sampling approach and were eligible for pooling given adequate ethical approval and availability of essential variables. Study-specific adjusted effect estimates were calculated using inverse probability of treatment-weighted linear and log-binomial regression models and pooled using a random-effects model. The adjusted risk of delivering a baby with LBW was 8.8% among women with malaria infection at antenatal enrollment compared to 7.7% among uninfected women (adjusted risk ratio [aRR] 1.14 [95% confidence interval (CI): 0.91, 1.42]; N = 13,613), 10.5% among women with malaria infection at delivery compared to 7.9% among uninfected women (aRR 1.32 [95% CI: 1.08, 1.62]; N = 11,826), and 15.3% among women with low mid-upper arm circumference (MUAC <23 cm) at enrollment compared to 9.5% among women with MUAC ≥ 23 cm (aRR 1.60 [95% CI: 1.36, 1.87]; N = 9,008). The risk of delivering a baby with LBW was 17.8% among women with both malaria infection and low MUAC at enrollment compared to 8.4% among uninfected women with MUAC ≥ 23 cm (joint aRR 2.13 [95% CI: 1.21, 3.73]; N = 8,152). There was no evidence of synergism (i.e., excess risk due to interaction) between malaria infection and MUAC on the multiplicative (p = 0.5) or additive scale (p = 0.9). Results were similar using body mass index (BMI) as an anthropometric indicator of nutritional status. Meta-regression results indicated that there may be multiplicative interaction between malaria infection at enrollment and low MUAC within studies conducted in Africa; however, this finding was not consistent on the additive scale, when accounting for multiple comparisons, or when using other definitions of malaria and malnutrition. The major limitations of the study included availability of only 2 cross-sectional measurements of malaria and the limited availability of ultrasound-based pregnancy dating to assess impacts on preterm birth and fetal growth in all studies. CONCLUSIONS: Pregnant women with malnutrition and malaria infection are at increased risk of LBW compared to women with only 1 risk factor or none, but malaria and malnutrition do not act synergistically. |
Personal protective equipment supply chain: Lessons learned from recent public health emergency responses
Patel A , D'Alessandro MM , Ireland KJ , Burel WG , Wencil EB , Rasmussen SA . Health Secur 2017 15 (3) 244-252 Personal protective equipment (PPE) that protects healthcare workers from infection is a critical component of infection control strategies in healthcare settings. During a public health emergency response, protecting healthcare workers from infectious disease is essential, given that they provide clinical care to those who fall ill, have a high risk of exposure, and need to be assured of occupational safety. Like most goods in the United States, the PPE market supply is based on demand. The US PPE supply chain has minimal ability to rapidly surge production, resulting in challenges to meeting large unexpected increases in demand that might occur during a public health emergency. Additionally, a significant proportion of the supply chain is produced off-shore and might not be available to the US market during an emergency because of export restrictions or nationalization of manufacturing facilities. Efforts to increase supplies during previous public health emergencies have been challenging. During the 2009 H1N1 influenza pandemic and the 2014 Ebola virus epidemic, the commercial supply chain of pharmaceutical and healthcare products quickly became critical response components. This article reviews lessons learned from these responses from a PPE supply chain and systems perspective and examines ways to improve PPE readiness for future responses. |
First-trimester artemisinin derivatives and quinine treatments and the risk of adverse pregnancy outcomes in Africa and Asia: A meta-analysis of observational studies
Dellicour S , Sevene E , McGready R , Tinto H , Mosha D , Manyando C , Rulisa S , Desai M , Ouma P , Oneko M , Vala A , Ruperez M , Macete E , Menendez C , Nakanabo-Diallo S , Kazienga A , Valea I , Calip G , Augusto O , Genton B , Njunju EM , Moore KA , d'Alessandro U , Nosten F , Ter Kuile F , Stergachis A . PLoS Med 2017 14 (5) e1002290 BACKGROUND: Animal embryotoxicity data, and the scarcity of safety data in human pregnancies, have prevented artemisinin derivatives from being recommended for malaria treatment in the first trimester except in lifesaving circumstances. We conducted a meta-analysis of prospective observational studies comparing the risk of miscarriage, stillbirth, and major congenital anomaly (primary outcomes) among first-trimester pregnancies treated with artemisinin derivatives versus quinine or no antimalarial treatment. METHODS AND FINDINGS: Electronic databases including Medline, Embase, and Malaria in Pregnancy Library were searched, and investigators contacted. Five studies involving 30,618 pregnancies were included; four from sub-Saharan Africa (n = 6,666 pregnancies, six sites) and one from Thailand (n = 23,952). Antimalarial exposures were ascertained by self-report or active detection and confirmed by prescriptions, clinic cards, and outpatient registers. Cox proportional hazards models, accounting for time under observation and gestational age at enrollment, were used to calculate hazard ratios. Individual participant data (IPD) meta-analysis was used to combine the African studies, and the results were then combined with those from Thailand using aggregated data meta-analysis with a random effects model. There was no difference in the risk of miscarriage associated with the use of artemisinins anytime during the first trimester (n = 37/671) compared with quinine (n = 96/945; adjusted hazard ratio [aHR] = 0.73 [95% CI 0.44, 1.21], I2 = 0%, p = 0.228), in the risk of stillbirth (artemisinins, n = 10/654; quinine, n = 11/615; aHR = 0.29 [95% CI 0.08-1.02], p = 0.053), or in the risk of miscarriage and stillbirth combined (pregnancy loss) (aHR = 0.58 [95% CI 0.36-1.02], p = 0.099). The corresponding risks of miscarriage, stillbirth, and pregnancy loss in a sensitivity analysis restricted to artemisinin exposures during the embryo sensitive period (6-12 wk gestation) were as follows: aHR = 1.04 (95% CI 0.54-2.01), I2 = 0%, p = 0.910; aHR = 0.73 (95% CI 0.26-2.06), p = 0.551; and aHR = 0.98 (95% CI 0.52-2.04), p = 0.603. The prevalence of major congenital anomalies was similar for first-trimester artemisinin (1.5% [95% CI 0.6%-3.5%]) and quinine exposures (1.2% [95% CI 0.6%-2.4%]). Key limitations of the study include the inability to control for confounding by indication in the African studies, the paucity of data on potential confounders, the limited statistical power to detect differences in congenital anomalies, and the lack of assessment of cardiovascular defects in newborns. CONCLUSIONS: Compared to quinine, artemisinin treatment in the first trimester was not associated with an increased risk of miscarriage or stillbirth. While the data are limited, they indicate no difference in the prevalence of major congenital anomalies between treatment groups. The benefits of 3-d artemisinin combination therapy regimens to treat malaria in early pregnancy are likely to outweigh the adverse outcomes of partially treated malaria, which can occur with oral quinine because of the known poor adherence to 7-d regimens. REVIEW REGISTRATION: PROSPERO CRD42015032371. |
Maternal Malaria and Malnutrition (M3) initiative, a pooled birth cohort of 13 pregnancy studies in Africa and the Western Pacific
Unger HW , Cates JE , Gutman J , Briand V , Fievet N , Valea I , Tinto H , d'Alessandro U , Landis SH , Adu-Afarwuah S , Dewey KG , Ter Kuile F , Dellicour S , Ouma P , Slutsker L , Terlouw DJ , Kariuki S , Ayisi J , Nahlen B , Desai M , Madanitsa M , Kalilani-Phiri L , Ashorn P , Maleta K , Mueller I , Stanisic D , Schmiegelow C , Lusingu J , Westreich D , van Eijk AM , Meshnick S , Rogerson S . BMJ Open 2016 6 (12) e012697 PURPOSE: The Maternal Malaria and Malnutrition (M3) initiative has pooled together 13 studies with the hope of improving understanding of malaria-nutrition interactions during pregnancy and to foster collaboration between nutritionists and malariologists. PARTICIPANTS: Data were pooled on 14 635 singleton, live birth pregnancies from women who had participated in 1 of 13 pregnancy studies. The 13 studies cover 8 countries in Africa and Papua New Guinea in the Western Pacific conducted from 1996 to 2015. FINDINGS TO DATE: Data are available at the time of antenatal enrolment of women into their respective parent study and at delivery. The data set comprises essential data such as malaria infection status, anthropometric assessments of maternal nutritional status, presence of anaemia and birth weight, as well as additional variables such gestational age at delivery for a subset of women. Participating studies are described in detail with regard to setting and primary outcome measures, and summarised data are available from each contributing cohort. FUTURE PLANS: This pooled birth cohort is the largest pregnancy data set to date to permit a more definite evaluation of the impact of plausible interactions between poor nutritional status and malaria infection in pregnant women on fetal growth and gestational length. Given the current comparative lack of large pregnancy cohorts in malaria-endemic settings, compilation of suitable pregnancy cohorts is likely to provide adequate statistical power to assess malaria-nutrition interactions, and could point towards settings where such interactions are most relevant. The M3 cohort may thus help to identify pregnant women at high risk of adverse outcomes who may benefit from tailored intensive antenatal care including nutritional supplements and alternative or intensified malaria prevention regimens, and the settings in which these interventions would be most effective. |
Assessment of the safety of antimalarial drug use during early pregnancy (ASAP): protocol for a multicenter prospective cohort study in Burkina Faso, Kenya and Mozambique
Tinto H , Sevene E , Dellicour S , Calip GS , d'Alessandro U , Macete E , Nakanabo-Diallo S , Kazienga A , Valea I , Sorgho H , Vala A , Augusto O , Ruperez M , Menendez C , Ouma P , Desai M , Ter Kuile F , Stergachis A . Reprod Health 2015 12 (1) 112 BACKGROUND: A major unresolved safety concern for malaria case management is the use of artemisinin combination therapies (ACTs) in the first trimester of pregnancy. There is a need for human data to inform policy makers and treatment guidelines on the safety of artemisinin combination therapies (ACT) when used during early pregnancy. METHODS: The overall goal of this paper is to describe the methods and implementation of a study aimed at developing surveillance systems for identifying exposures to antimalarials during early pregnancy and for monitoring pregnancy outcomes using health and demographic surveillance platforms. This was a multi-center prospective observational cohort study involving women at health and demographic surveillance sites in three countries in Africa: Burkina Faso, Kenya and Mozambique [(ClinicalTrials.gov Identifier: NCT01232530)]. The study was designed to identify pregnant women with artemisinin exposure in the first trimester and compare them to: 1) pregnant women without malaria, 2) pregnant women treated for malaria, but exposed to other antimalarials, and 3) pregnant women with malaria and treated with artemisinins in the 2nd or 3rd trimesters from the same settings. Pregnant women were recruited through community-based surveys and attendance at health facilities, including antenatal care clinics and followed until delivery. Data from the three sites will be pooled for analysis at the end of the study. Results are forthcoming. DISCUSSION: Despite few limitations, the methods described here are relevant to the development of sustainable pharmacovigilance systems for drugs used by pregnant women in the tropics using health and demographic surveillance sites to prospectively ascertain drug safety in early pregnancy. TRIAL REGISTRATION: NCT01232530. |
Genetic Diversity and Protective Efficacy of the RTS,S/AS01 Malaria Vaccine.
Neafsey DE , Juraska M , Bedford T , Benkeser D , Valim C , Griggs A , Lievens M , Abdulla S , Adjei S , Agbenyega T , Agnandji ST , Aide P , Anderson S , Ansong D , Aponte JJ , Asante KP , Bejon P , Birkett AJ , Bruls M , Connolly KM , D'Alessandro U , Dobano C , Gesase S , Greenwood B , Grimsby J , Tinto H , Hamel MJ , Hoffman I , Kamthunzi P , Kariuki S , Kremsner PG , Leach A , Lell B , Lennon NJ , Lusingu J , Marsh K , Martinson F , Molel JT , Moss EL , Njuguna P , Ockenhouse CF , Ragama Ogutu B , Otieno W , Otieno L , Otieno K , Owusu-Agyei S , Park DJ , Pellé K , Robbins D , Russ C , Ryan EM , Sacarlal J , Sogoloff B , Sorgho H , Tanner M , Theander T , Valea I , Volkman SK , Yu Q , Lapierre D , Birren BW , Gilbert PB , Wirth DF . N Engl J Med 2015 373 (21) 2025-2037 BACKGROUND: The RTS,S/AS01 vaccine targets the circumsporozoite protein of Plasmodium falciparum and has partial protective efficacy against clinical and severe malaria disease in infants and children. We investigated whether the vaccine efficacy was specific to certain parasite genotypes at the circumsporozoite protein locus. METHODS: We used polymerase chain reaction-based next-generation sequencing of DNA extracted from samples from 4985 participants to survey circumsporozoite protein polymorphisms. We evaluated the effect that polymorphic positions and haplotypic regions within the circumsporozoite protein had on vaccine efficacy against first episodes of clinical malaria within 1 year after vaccination. RESULTS: In the per-protocol group of 4577 RTS,S/AS01-vaccinated participants and 2335 control-vaccinated participants who were 5 to 17 months of age, the 1-year cumulative vaccine efficacy was 50.3% (95% confidence interval [CI], 34.6 to 62.3) against clinical malaria in which parasites matched the vaccine in the entire circumsporozoite protein C-terminal (139 infections), as compared with 33.4% (95% CI, 29.3 to 37.2) against mismatched malaria (1951 infections) (P=0.04 for differential vaccine efficacy). The vaccine efficacy based on the hazard ratio was 62.7% (95% CI, 51.6 to 71.3) against matched infections versus 54.2% (95% CI, 49.9 to 58.1) against mismatched infections (P=0.06). In the group of infants 6 to 12 weeks of age, there was no evidence of differential allele-specific vaccine efficacy. CONCLUSIONS: These results suggest that among children 5 to 17 months of age, the RTS,S vaccine has greater activity against malaria parasites with the matched circumsporozoite protein allele than against mismatched malaria. The overall vaccine efficacy in this age category will depend on the proportion of matched alleles in the local parasite population; in this trial, less than 10% of parasites had matched alleles. (Funded by the National Institutes of Health and others.). |
Clinical determinants of early parasitological response to ACTs in African patients with uncomplicated falciparum malaria: a literature review and meta-analysis of individual patient data
Abdulla S , Adam I , Adjei GO , Adjuik MA , Alemayehu B , Allan R , Arinaitwe E , Ashley EA , Ba MS , Barennes H , Barnes KI , Bassat Q , Baudin E , Berens-Riha N , Bjorkman A , Bompart F , Bonnet M , Borrmann S , Bousema T , Brasseur P , Bukirwa H , Checchi F , Dahal P , D'Alessandro U , Desai M , Dicko A , Djimde AA , Dorsey G , Doumbo OK , Drakeley CJ , Duparc S , Eshetu T , Espie E , Etard JF , Faiz AM , Falade CO , Fanello CI , Faucher JF , Faye B , Faye O , Filler S , Flegg JA , Fofana B , Fogg C , Gadalla NB , Gaye O , Genton B , Gething PW , Gil JP , Gonzalez R , Grandesso F , Greenhouse B , Greenwood B , Grivoyannis A , Guerin PJ , Guthmann JP , Hamed K , Hamour S , Hay SI , Hode EM , Humphreys GS , Hwang J , Ibrahim ML , Jima D , Jones JJ , Jullien V , Juma E , Kachur PS , Kager PA , Kamugisha E , Kamya MR , Karema C , Kayentao K , Kieche JR , Kironde F , Kofoed PE , Kremsner PG , Krishna S , Lameyre V , Lell B , Lima A , Makanga M , Malik EM , Marsh K , Martensson A , Massougbodji A , Menan H , Menard D , Menendez C , Mens PF , Meremikwu M , Moreira C , Nabasumba C , Nambozi M , Ndiaye JL , Ngasala BE , Nikiema F , Nsanzabana C , Ntoumi F , Oguike M , Ogutu BR , Olliaro P , Omar SA , Ouedraogo JB , Owusu-Agyei S , Penali LK , Pene M , Peshu J , Piola P , Plowe CV , Premji Z , Price RN , Randrianarivelojosia M , Rombo L , Roper C , Rosenthal PJ , Sagara I , Same-Ekobo A , Sawa P , Schallig HDFH , Schramm B , Seck A , Shekalaghe SA , Sibley CH , Sinou V , Sirima SB , Some FA , Sow D , Staedke SG , Stepniewska K , Sutherland CJ , Swarthout TD , Sylla K , Talisuna AO , Taylor WRJ , Temu EA , Thwing JI , Tine RCK , Tinto H , Tommasini S , Toure OA , Ursing J , Vaillant MT , Valentini G , Van den Broek I , Vugt MV , Ward SA , Winstanley PA , Yavo W , Yeka A , Zolia YM , Zongo I , WWARN Artemisinin based Combination Therapy (ACT) Africa Baseline Study Group . BMC Med 2015 13 212 BACKGROUND: Artemisinin-resistant Plasmodium falciparum has emerged in the Greater Mekong sub-region and poses a major global public health threat. Slow parasite clearance is a key clinical manifestation of reduced susceptibility to artemisinin. This study was designed to establish the baseline values for clearance in patients from Sub-Saharan African countries with uncomplicated malaria treated with artemisinin-based combination therapies (ACTs). METHODS: A literature review in PubMed was conducted in March 2013 to identify all prospective clinical trials (uncontrolled trials, controlled trials and randomized controlled trials), including ACTs conducted in Sub-Saharan Africa, between 1960 and 2012. Individual patient data from these studies were shared with the WorldWide Antimalarial Resistance Network (WWARN) and pooled using an a priori statistical analytical plan. Factors affecting early parasitological response were investigated using logistic regression with study sites fitted as a random effect. The risk of bias in included studies was evaluated based on study design, methodology and missing data. RESULTS: In total, 29,493 patients from 84 clinical trials were included in the analysis, treated with artemether-lumefantrine (n = 13,664), artesunate-amodiaquine (n = 11,337) and dihydroartemisinin-piperaquine (n = 4,492). The overall parasite clearance rate was rapid. The parasite positivity rate (PPR) decreased from 59.7 % (95 % CI: 54.5-64.9) on day 1 to 6.7 % (95 % CI: 4.8-8.7) on day 2 and 0.9 % (95 % CI: 0.5-1.2) on day 3. The 95th percentile of observed day 3 PPR was 5.3 %. Independent risk factors predictive of day 3 positivity were: high baseline parasitaemia (adjusted odds ratio (AOR) = 1.16 (95 % CI: 1.08-1.25); per 2-fold increase in parasite density, P <0.001); fever (>37.5 degreeC) (AOR = 1.50 (95 % CI: 1.06-2.13), P = 0.022); severe anaemia (AOR = 2.04 (95 % CI: 1.21-3.44), P = 0.008); areas of low/moderate transmission setting (AOR = 2.71 (95 % CI: 1.38-5.36), P = 0.004); and treatment with the loose formulation of artesunate-amodiaquine (AOR = 2.27 (95 % CI: 1.14-4.51), P = 0.020, compared to dihydroartemisinin-piperaquine). CONCLUSIONS: The three ACTs assessed in this analysis continue to achieve rapid early parasitological clearance across the sites assessed in Sub-Saharan Africa. A threshold of 5 % day 3 parasite positivity from a minimum sample size of 50 patients provides a more sensitive benchmark in Sub-Saharan Africa compared to the current recommended threshold of 10 % to trigger further investigation of artemisinin susceptibility. |
Evaluation of respiratory protection programs and practices in California hospitals during the 2009-2010 H1N1 influenza pandemic
Beckman S , Materna B , Goldmacher S , Zipprich J , D'Alessandro M , Novak D , Harrison R . Am J Infect Control 2013 41 (11) 1024-31 BACKGROUND: Emergence of the novel 2009 influenza A H1N1 virus in California led to an evaluation of hospital respiratory protection programs (RPPs) and practices by the California Department of Public Health during the 2009-2010 influenza season. METHODS: Onsite evaluation of 16 hospitals consisted of interviews with managers and health care workers about RPPs and practices, review of written RPPs, and limited observations of personnel using respirators. Data were analyzed using descriptive statistics. RESULTS: All hospitals had implemented policies requiring the minimum use of N95 filtering facepiece respirators when working with patients with H1N1 virus infection; 95.5% of health care workers (n = 199) reported they would wear at least this level of protection when in close contact with a patient with confirmed or suspected H1N1 virus infection. However, evaluation of written RPPs indicated deficiencies in required areas, most commonly in recordkeeping, designation of a program administrator, program evaluation, employee training, and fit testing procedures. CONCLUSIONS: Health care workers were aware of respiratory protection required when providing care for patients with confirmed or suspected H1N1 virus infection. Hospitals should improve written RPPs, fully implement written procedures, and conduct periodic program evaluation to ensure effectiveness of respirator use for health care worker protection. Increased accessibility of resources tailored for hospital respirator program administrators may be helpful. |
A phase 3 trial of RTS,S/AS01 malaria vaccine in African infants
Agnandji ST , Lell B , Fernandes JF , Abossolo BP , Methogo BG , Kabwende AL , Adegnika AA , Mordmüller B , Issifou S , Kremsner PG , Sacarlal J , Aide P , Lanaspa M , Aponte JJ , Machevo S , Acacio S , Bulo H , Sigauque B , Macete E , Alonso P , Abdulla S , Salim N , Minja R , Mpina M , Ahmed S , Ali AM , Mtoro AT , Hamad AS , Mutani P , Tanner M , Tinto H , D'Alessandro U , Sorgho H , Valea I , Bihoun B , Guiraud I , Kaboré B , Sombié O , Guiguemdé RT , Ouédraogo JB , Hamel MJ , Kariuki S , Oneko M , Odero C , Otieno K , Awino N , McMorrow M , Muturi-Kioi V , Laserson KF , Slutsker L , Otieno W , Otieno L , Otsyula N , Gondi S , Otieno A , Owira V , Oguk E , Odongo G , Woods JB , Ogutu B , Njuguna P , Chilengi R , Akoo P , Kerubo C , Maingi C , Lang T , Olotu A , Bejon P , Marsh K , Mwambingu G , Owusu-Agyei S , Asante KP , Osei-Kwakye K , Boahen O , Dosoo D , Asante I , Adjei G , Kwara E , Chandramohan D , Greenwood B , Lusingu J , Gesase S , Malabeja A , Abdul O , Mahende C , Liheluka E , Malle L , Lemnge M , Theander TG , Drakeley C , Ansong D , Agbenyega T , Adjei S , Boateng HO , Rettig T , Bawa J , Sylverken J , Sambian D , Sarfo A , Agyekum A , Martinson F , Hoffman I , Mvalo T , Kamthunzi P , Nkomo R , Tembo T , Tegha G , Tsidya M , Kilembe J , Chawinga C , Ballou WR , Cohen J , Guerra Y , Jongert E , Lapierre D , Leach A , Lievens M , Ofori-Anyinam O , Olivier A , Vekemans J , Carter T , Kaslow D , Leboulleux D , Loucq C , Radford A , Savarese B , Schellenberg D , Sillman M , Vansadia P . N Engl J Med 2012 367 (24) 2284-95 BACKGROUND: The candidate malaria vaccine RTS,S/AS01 reduced episodes of both clinical and severe malaria in children 5 to 17 months of age by approximately 50% in an ongoing phase 3 trial. We studied infants 6 to 12 weeks of age recruited for the same trial. METHODS: We administered RTS,S/AS01 or a comparator vaccine to 6537 infants who were 6 to 12 weeks of age at the time of the first vaccination in conjunction with Expanded Program on Immunization (EPI) vaccines in a three-dose monthly schedule. Vaccine efficacy against the first or only episode of clinical malaria during the 12 months after vaccination, a coprimary end point, was analyzed with the use of Cox regression. Vaccine efficacy against all malaria episodes, vaccine efficacy against severe malaria, safety, and immunogenicity were also assessed. RESULTS: The incidence of the first or only episode of clinical malaria in the intention-to-treat population during the 14 months after the first dose of vaccine was 0.31 per person-year in the RTS,S/AS01 group and 0.40 per person-year in the control group, for a vaccine efficacy of 30.1% (95% confidence interval [CI], 23.6 to 36.1). Vaccine efficacy in the per-protocol population was 31.3% (97.5% CI, 23.6 to 38.3). Vaccine efficacy against severe malaria was 26.0% (95% CI, -7.4 to 48.6) in the intention-to-treat population and 36.6% (95% CI, 4.6 to 57.7) in the per-protocol population. Serious adverse events occurred with a similar frequency in the two study groups. One month after administration of the third dose of RTS,S/AS01, 99.7% of children were positive for anti-circumsporozoite antibodies, with a geometric mean titer of 209 EU per milliliter (95% CI, 197 to 222). CONCLUSIONS: The RTS,S/AS01 vaccine coadministered with EPI vaccines provided modest protection against both clinical and severe malaria in young infants. (Funded by GlaxoSmithKline Biologicals and the PATH Malaria Vaccine Initiative; RTS,S ClinicalTrials.gov number: NCT00866619.). |
First results of phase 3 trial of RTS,S/AS01 malaria vaccine in African children
Agnandji ST , Lell B , Soulanoudjingar SS , Fernandes JF , Abossolo BP , Conzelmann C , Methogo BG , Doucka Y , Flamen A , Mordmüller B , Issifou S , Kremsner PG , Sacarlal J , Aide P , Lanaspa M , Aponte JJ , Nhamuave A , Quelhas D , Bassat Q , Mandjate S , Macete E , Alonso P , Abdulla S , Salim N , Juma O , Shomari M , Shubis K , Machera F , Hamad AS , Minja R , Mtoro A , Sykes A , Ahmed S , Urassa AM , Ali AM , Mwangoka G , Tanner M , Tinto H , D'Alessandro U , Sorgho H , Valea I , Tahita MC , Kaboré W , Ouédraogo S , Sandrine Y , Guiguemdé RT , Ouédraogo JB , Hamel MJ , Kariuki S , Odero C , Oneko M , Otieno K , Awino N , Omoto J , Williamson J , Muturi-Kioi V , Laserson KF , Slutsker L , Otieno W , Otieno L , Nekoye O , Gondi S , Otieno A , Ogutu B , Wasuna R , Owira V , Jones D , Onyango AA , Njuguna P , Chilengi R , Akoo P , Kerubo C , Gitaka J , Maingi C , Lang T , Olotu A , Tsofa B , Bejon P , Peshu N , Marsh K , Owusu-Agyei S , Asante KP , Osei-Kwakye K , Boahen O , Ayamba S , Kayan K , Owusu-Ofori R , Dosoo D , Asante I , Adjei G , Adjei G , Chandramohan D , Greenwood B , Lusingu J , Gesase S , Malabeja A , Abdul O , Kilavo H , Mahende C , Liheluka E , Lemnge M , Theander T , Drakeley C , Ansong D , Agbenyega T , Adjei S , Boateng HO , Rettig T , Bawa J , Sylverken J , Sambian D , Agyekum A , Owusu L , Martinson F , Hoffman I , Mvalo T , Kamthunzi P , Nkomo R , Msika A , Jumbe A , Chome N , Nyakuipa D , Chintedza J , Ballou WR , Bruls M , Cohen J , Guerra Y , Jongert E , Lapierre D , Leach A , Lievens M , Ofori-Anyinam O , Vekemans J , Carter T , Leboulleux D , Loucq C , Radford A , Savarese B , Schellenberg D , Sillman M , Vansadia P . N Engl J Med 2011 365 (20) 1863-75 BACKGROUND: An ongoing phase 3 study of the efficacy, safety, and immunogenicity of candidate malaria vaccine RTS,S/AS01 is being conducted in seven African countries. METHODS: From March 2009 through January 2011, we enrolled 15,460 children in two age categories--6 to 12 weeks of age and 5 to 17 months of age--for vaccination with either RTS,S/AS01 or a non-malaria comparator vaccine. The primary end point of the analysis was vaccine efficacy against clinical malaria during the 12 months after vaccination in the first 6000 children 5 to 17 months of age at enrollment who received all three doses of vaccine according to protocol. After 250 children had an episode of severe malaria, we evaluated vaccine efficacy against severe malaria in both age categories. RESULTS: In the 14 months after the first dose of vaccine, the incidence of first episodes of clinical malaria in the first 6000 children in the older age category was 0.32 episodes per person-year in the RTS,S/AS01 group and 0.55 episodes per person-year in the control group, for an efficacy of 50.4% (95% confidence interval [CI], 45.8 to 54.6) in the intention-to-treat population and 55.8% (97.5% CI, 50.6 to 60.4) in the per-protocol population. Vaccine efficacy against severe malaria was 45.1% (95% CI, 23.8 to 60.5) in the intention-to-treat population and 47.3% (95% CI, 22.4 to 64.2) in the per-protocol population. Vaccine efficacy against severe malaria in the combined age categories was 34.8% (95% CI, 16.2 to 49.2) in the per-protocol population during an average follow-up of 11 months. Serious adverse events occurred with a similar frequency in the two study groups. Among children in the older age category, the rate of generalized convulsive seizures after RTS,S/AS01 vaccination was 1.04 per 1000 doses (95% CI, 0.62 to 1.64). CONCLUSIONS: The RTS,S/AS01 vaccine provided protection against both clinical and severe malaria in African children. (Funded by GlaxoSmithKline Biologicals and the PATH Malaria Vaccine Initiative; RTS,S ClinicalTrials.gov number, NCT00866619 .) |
- Page last reviewed:Feb 1, 2024
- Page last updated:Oct 07, 2024
- Content source:
- Powered by CDC PHGKB Infrastructure