Last data update: Mar 21, 2025. (Total: 48935 publications since 2009)
Records 1-30 (of 38 Records) |
Query Trace: Abubakar A[original query] |
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Feasibility of cohort event monitoring and assessment of reactogenicity and adverse events among a cohort of AstraZeneca and Moderna COVID-19 vaccine recipients in Nigeria, 2021
Bolu O , Alo OD , Iwara E , Longley AT , Hadley I , Ogar CK , Ezekwe C , Elemuwa U , Adedokun O , Ramadhani HO , Ohakanu S , Ortiz N , Antonza G , Abubakar A , Asekun A , Fraden B , Chen R , Nordenberg D , Adebajo S , Adeyeye MC , Stafford KA . Vaccine 2025 52 126907 BACKGROUND: To generate COVID-19 vaccine safety data in Nigeria, passive reporting was supplemented with cohort event monitoring (CEM), an active surveillance system. We described reactogenicity within 7 days and adverse events up to 3 months after each AstraZeneca or Moderna COVID-19 vaccine dose while assessing the feasibility of implementing CEM in a low- to middle-income country (LMIC) during a mass vaccination campaign. METHODS: Participants were aged ≥18 years with access to mobile phones who received the first dose of an authorized COVID-19 vaccine from participating health facilities in 6 states of Nigeria during September and October 2021. Data collectors interviewed participants via phone on days 0, 3, 7, and thereafter every 7 days for 3 months. The same schedule was restarted if a participant received a second vaccine dose. Proportions of participant-reported adverse events following COVID-19 vaccine receipt were calculated. Investigation and causality assessment were conducted on deaths using the World Health Organization causality guidelines. RESULTS: We enrolled 12,317 participants (AstraZeneca 6990; Moderna 5327); 6167/6990 (88.2 %) AstraZeneca and 4879/5327 (91.6 %) Moderna recipients completed a follow-up interview days 0-7 after the first dose; among them, 2685/6167 (43.5 %) AstraZeneca and 3533/4879 (72.4 %) Moderna recipients reported local reactions and 2456/6167 (39.8 %) AstraZeneca and 2087/4879 (42.8 %) Moderna recipients reported systemic reactions. Overall, 3891/6990 (55.7 %) AstraZeneca and 3978/5327 (72.8 %) Moderna recipients received a second dose of COVID-19 vaccine, among whom 897/3891 (23 %) AstraZeneca and 1979/3978 (49.7 %) Moderna recipients reported local reactions and 727/3891 (18.7 %) AstraZeneca and 1680/3978 (42.2 %) Moderna recipients reported systemic reactions. Among all enrolled, 11 died; there was no evidence to suggest any deaths were vaccine-related. CONCLUSIONS: No unexpected patterns of adverse events were detected, providing additional data on the safety of these COVID-19 vaccines in Nigerian adults. We demonstrated that implementing CEM was feasible and may be valuable for safety monitoring of vaccines introduced in LMICs. |
Updates on the treatment of drug-susceptible and drug-resistant tuberculosis an official ATS/CDC/ERS/IDSA clinical practice guideline
Duarte R , Munsiff SS , Nahid P , Saukkonen JJ , Winston CA , Abubakar I , Acuña-Villaorduña C , Barry PM , Bastos ML , Carr W , Chami H , Chen LL , Chorba T , Daley CL , Garcia-Prats AJ , Holland K , Konstantinidis I , Lipman M , Mammen MJ , Migliori GB , Parvez FM , Shapiro AE , Sotgiu G , Starke JR , Starks AM , Thakore S , Wang SH , Wortham JM . Am J Respir Crit Care Med 2025 211 (1) 15-33 Background: On the basis of recent clinical trial data for the treatment of drug-susceptible and drug-resistant tuberculosis (TB), the American Thoracic Society, U.S. Centers for Disease Control and Prevention, European Respiratory Society, and Infectious Diseases Society of America have updated clinical practice guidelines for TB treatment in children and adults in settings in which mycobacterial cultures, molecular and phenotypic drug susceptibility tests, and radiographic studies, among other diagnostic tools, are available on a routine basis. Methods: A Joint Panel representing multiple interdisciplinary perspectives convened with American Thoracic Society methodologists to review evidence and make recommendations using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) and GRADE-ADOLOPMENT (adoption, adaptation, and, as needed, de novo development of recommendations) methodology. Results: New drug-susceptible TB recommendations include the use of a novel 4-month regimen for people with pulmonary TB and a shortened 4-month regimen for children with nonsevere TB. Drug-resistant TB recommendation updates include the use of novel regimens containing bedaquiline, pretomanid, and linezolid with or without moxifloxacin. Conclusions: All-oral, shorter treatment regimens for TB are now recommended for use in eligible individuals. Copyright © 2025 by the American Thoracic Society. |
Principal component analysis of the serological response to plasmodium falciparum using a multiplex bead-based assay in Nigeria
Schultz JS , Okoli M , Lee S , Leonard CM , Sayre D , Heilig CM , Uhomoibhi P , Ogunniyi A , Ndodo N , Mba N , Abubakar AG , Akinmulero O , Dawurung AB , Okoye M , Iriemenam NC , Plucinski M , Steinhardt L , Rogier E , Ihekweazu C . Sci Rep 2024 14 (1) 30658 Characterization of serological responses to Plasmodium falciparum (Pf) is of interest to understand disease burden and transmission dynamics; however, their interpretation is challenging. Dried blood spots from 30,815 participants aged 6 months to 15 years from the 2018 Nigeria HIV/AIDS Indicator and Impact Survey were analyzed by multiplex bead-based assay to measure immunoglobulin G (IgG) to Pf-stage-specific MSP-1, AMA-1, GLURPR0, LSA-1, and CSP. These IgG levels were analyzed by principal component analysis (PCA). PC1 and PC2 scores explained 41% and 17% of the total variance, respectively. PC1 unit vectors represented seropositivity. PC2 unit vectors for blood-stage antigens were in opposite directions to liver-stage and sporozoite antigens. PC2 scores were correlated with MSP-1 positively (R = 0.52, P < 0.001) and CSP negatively (R=-0.65, P < 0.001) and may help identify areas with prior exposure but higher risk for increased infections or epidemics. PCA of Pf serology can provide summary scores to possibly inform future programmatic interventions. |
Development and implementation of a public health event management system, Nigeria, 2018-2024
Elston J , Eteng WO , Ihekweazu C , Oliver I , Aniaku E , Abubakar A , Lee CT , Benyeogor E , Roddick I , Logan S , Okereke E , Inamdar L , Aruna O , Luka-Lawal R , Manthey C , Hinkle L , Nunez G , Agogo E , Usman R , Sunday EL , Hassan M , Oladejo J , Adetifa I . Emerg Infect Dis 2025 31 (1) 4-13 Event management systems (EMS) are key tools for epidemic intelligence, integrating surveillance signals and incident response, although international standards to inform development are lacking. We describe the Nigeria Centre for Disease Control and Prevention (NCDC) SITAware, a software capable of operating with low internet bandwidth to generate notifications, reports, and spatiotemporal dashboards and provide event-level data for real-time accountability and postevent learning. SITAware was enabled by local institutional ownership, co-created at low cost, and integrated into existing workflows. In 2022, SITAware was used to manage ≈300 incidents, and NCDC implemented it subnationally. NCDC's experience may inform EMS development and implementation in similar settings. |
Monitoring workers' health: focus on rights, determinants, and equity
Pega F , Momen NC , Abubakar AHA , Al-Emam R , Hassan MN , Howard J , Hussein SH , Iavicoli S , Kevi SK , Kgalamono SM , Malik SMR , K GM , Osman AY , Pandav RS , Shrestha RRP , Singh DR , Sun X , Wotobe MK , Neira MP . Lancet 2023 402 (10410) 1306-1308 The Lancet Series on Work and Health1, 2, 3 recognises that changes in the world of work are causing new occupational hazards to physical and mental health and increasing health inequalities within and between countries. These changes have profound implications for official workers’ health data and monitoring systems, which have become a global health priority as the world seeks to reach the Sustainable Development Goals (SDGs).4, 5 These monitoring systems are public goods that provide international organisations, governments, and communities the evidence base for policy and practice that ensures health for all workers. We argue that these monitoring systems must respond to changing working environments by expanding capture of workers’ rights, working conditions, and health inequalities. We outline normative data and monitoring products to reach this systemic shift and provide the public health vision for this new direction. | | No worker should die or get ill because of their work, or be left behind in occupational health protection and promotion. All workers are entitled to the human rights to: health;6 a clean, healthy, and sustainable environment; and a safe and healthy working environment.7 However, WHO and the International Labour Organization (ILO) estimate that annually 2 million deaths and 90 million disability-adjusted life-years are attributable to selected occupational risk factors.8 Recognition is growing that improving workers’ health and health equity requires action on the social and environmental determinants of health. Examples include strengthened evidence on the effects of the emerging psychosocial hazard of long working hours on cardiovascular disease,9 and the environmental and climate crises strengthening attention to workers’ environmental and climatic hazards (eg, air pollution and heat exposures). Occupational health policy increasingly comprises health equity analysis and targets. The WHO/ILO joint estimates show geographical and socioeconomic health inequalities—an increased number of deaths is noted among workers in Africa, South-East Asia, and the Western Pacific, and among men and people aged 55 years or older.8 People working in the informal economy, and migrant, outdoor, and front-line workers are often especially disadvantaged. Health-care workers, despite working in a sector that aims to restore, protect, and promote health, often face hazardous working conditions and are exposed to pathogens (eg, SARS-CoV-2), violence, and long working hours, among others. Ongoing changes in working environments (eg, globalisation, automation, digitisation, new pandemics, environmental pollution, and climate change) exacerbate these inequalities. Ultimately, unhealthy working conditions act as barriers for realising workers’ rights to health, population health, and health equity, and threaten the goal of achieving the SDGs globally. |
Dynamics of IgG antibody response against Plasmodium antigens among Nigerian infants and young children
Leonard CM , Uhomoibhi P , Abubakar A , Ogunniyi A , Mba N , Greby SM , Okoye MI , Iriemenam NC , Ihekweazu C , Steinhardt L , Rogier E . Front Immunol 2023 14 1208822 BACKGROUND: Plasmodium falciparum malaria is a leading cause of child mortality in Nigeria. Neonates are born with maternal antibodies from placental transfer which may protect against malaria infection in the first months of life. The IgG dynamics of the transition from passively transferred antimalarial antibodies to actively acquired IgG from natural exposure have not been well elucidated. METHODS: Blood samples collected during a 2018 Nigeria nationwide HIV/AIDS household survey were available for 9,443 children under 5 years of age, with a subset of infants under 2 months of age having maternal samples available (n=41). Samples were assayed for the P. falciparum HRP2 antigen and anti-malarial IgG antibodies. LOESS regression examined the dynamics in IgG response in the first 5 years of life. Correlation with maternal IgG levels was assessed for mother/child pairs. RESULTS: Consistent decreases were observed in median IgG levels against all Plasmodium spp. antigen targets for the first months of life. At a population level, P. falciparum apical membrane antigen-1 (AMA1) and merozoite surface protein-1 19kD (PfMSP1) IgG decreased during the first 12 months of life before reaching a nadir, whereas IgGs to other targets only declined for the first 4 months of life. Seropositivity showed a similar decline with the lowest seropositivity against AMA1 and PfMSP1 at 10-12 months, though remaining above 50% during the first 2 years of life in higher transmission areas. No protective association was observed between IgG positivity and P. falciparum infection in infants. Maternal antibody levels showed a strong positive correlation with infant antibody levels for all P. falciparum antigens from birth to 2 months of age, but this correlation was lost by 6 months of age. DISCUSSION: Maternally transferred anti-malarial IgG antibodies rapidly decline during the first 6 months of life, with variations among specific antigens and malaria transmission intensity. From 3-23 months of age, there was a wide range in IgG levels for the blood-stage antigens indicating high individual variation in antibody production as children are infected with malaria. Non-falciparum species-specific antigens showed similar patterns in waning immunity and correlation with paired mother's IgG levels compared to P. falciparum antigens. |
EMARIS Conference 2023: Convergence of science, policy, and practice on acute respiratory infections in post COVID-19 Eastern Mediterranean Region
Assiri A , Moen A , Brennan R , Abubakar A , Khan W , Al Mandhari A . Influenza Other Respir Viruses 2023 17 (3) e13129 Acute respiratory infection (ARI) is consistently ranked among the leading causes of morbidity and mortality worldwide. It kills more than 4 million people each year globally yet has been referred to as a “forgotten pandemic.” 1 New viral respiratory pathogens are emerging with increasing frequency and have demonstrated their potential for devastating global public health, socio‐economic and political impacts. 2 Within two decades, the world has faced an influenza A(H1N1) pdm09 pandemic and the emergence of three highly pathogenic and deadly human coronaviruses, namely SARS‐CoV, MERS‐CoV and SARS‐CoV‐2, the last one causing a pandemic. 3 As a result of the of recent pandemic, WHO has estimated the excess mortality due to COVID‐19, disease caused by SARS‐CoV‐2, to be 13.3–16.6 million deaths in addition to colossal economic and social disruption. 4 |
Treponemal antibody seroprevalence using a multiplex bead assay from samples collected during the 2018 Nigeria HIV/AIDS indicator and impact survey: Searching for yaws in Nigeria
Guagliardo SAJ , Parameswaran N , Agala N , Abubakar A , Cooley G , Ye T , Kamb M , Mba N , William N , Greby S , Iriemenam N , Alagi M , Okoye M , Martin D . Am J Trop Med Hyg 2023 108 (5) 977-980 Yaws is a chronic, relapsing disease of skin, bone, and cartilage caused by Treponema pallidum subsp. pertenue. Yaws was last reported in Nigeria in 1996, although neighboring countries have recently reported cases. We investigated serological evidence for yaws among children aged 0-14 years in Nigeria by measuring antibodies to the treponemal antigens rp17 and TmpA in blood specimens from a 2018 nationally representative HIV survey using a multiplex bead assay. The presence of antibodies to both antigens ("double positive") likely reflects current or recent treponemal infection. Overall, 1.9% (610/31,549) of children had anti-TmpA antibodies, 1.5% (476/31,549) had anti-rp17 antibodies, and 0.1% (39/31,549) were double positive. Among households, 0.5% (84/18,021) had a double-positive child, with a clustering of double-positive children. Although numbers are low, identification of antibodies to both TmpA and rp17 may warrant investigation, including more granular epidemiologic and clinical data, to assess the potential for continuing yaws transmission in Nigerian children. |
Non-falciparum malaria infection and IgG seroprevalence among children under 15 years in Nigeria, 2018
Herman C , Leonard CM , Uhomoibhi P , Maire M , Moss D , Inyang U , Abubakar A , Ogunniyi A , Mba N , Greby SM , Okoye MI , Iriemenam NC , Maikore I , Steinhardt L , Rogier E . Nat Commun 2023 14 (1) 1360 Plasmodium falciparum (Pf) is the dominant malaria parasite in Nigeria though P. vivax (Pv), P. ovale (Po), and P. malariae (Pm) are also endemic. Blood samples (n = 31,234) were collected from children aged 0-14 years during a 2018 nationwide HIV survey and assayed for Plasmodium antigenemia, Plasmodium DNA, and IgG against Plasmodium MSP1-19 antigens. Of all children, 6.6% were estimated to have Pm infection and 1.4% Po infection with no Pv infections detected. The highest household wealth quintile was strongly protective against infection with Pm (aOR: 0.11, 95% CI: 0.05-0.22) or Po (aOR= 0.01, 0.00-0.10). Overall Pm seroprevalence was 34.2% (95% CI: 33.3-35.2) with lower estimates for Po (12.1%, 11.6-12.5) and Pv (6.3%, 6.0-6.7). Pm seropositivity was detected throughout the country with several local government areas showing >50% seroprevalence. Serological and DNA indicators show widespread exposure of Nigerian children to Pm with lower rates to Po and Pv. |
Effect of Nigeria Presidential Task Force on COVID-19 pandemic, Nigeria
Bolu O , Mustapha B , Ihekweazu C , Muhammad M , Hassan A , Abdulwahab A , Asekun AA , Nsirim R , Okechukwu E , Attah I , Swaminathan M , Greby S , Adebiyi A , Alex-Okoh M , Okwor T , Ilori E , Mba N , Mutah J , Akujobi J , Battah N , Haggai W , Okatubo G , Okigbo A , Castle E , Abubakar I , Akataobi C , Adekunle O , Aliyu SH . Emerg Infect Dis 2022 28 (13) S168-s176 Nigeria had a confirmed case of COVID-19 on February 28, 2020. On March 17, 2020, the Nigerian Government inaugurated the Presidential Task Force (PTF) on COVID-19 to coordinate the country's multisectoral intergovernmental response. The PTF developed the National COVID-19 Multisectoral Pandemic Response Plan as the blueprint for implementing the response plans. The PTF provided funding, coordination, and governance for the public health response and executed resource mobilization and social welfare support, establishing the framework for containment measures and economic reopening. Despite the challenges of a weak healthcare infrastructure, staff shortages, logistic issues, commodity shortages, currency devaluation, and varying state government cooperation, high-level multisectoral PTF coordination contributed to minimizing the effects of the pandemic through early implementation of mitigation efforts, supported by a strong collaborative partnership with bilateral, multilateral, and private-sector organizations. We describe the lessons learned from the PTF COVID-19 for future multisectoral public health response. |
Plasmodium falciparum infection prevalence among children aged 6-59months from independent DHS and HIV surveys: Nigeria, 2018
Oviedo A , Abubakar A , Uhomoibhi P , Maire M , Inyang U , Audu B , Iriemenam NC , Ogunniyi A , Ssekitooleko J , Kalambo JA , Greby SM , Mba N , Swaminathan M , Ihekweazu C , Okoye MI , Rogier E , Steinhardt LC . Sci Rep 2023 13 (1) 1998 Prevalence estimates are critical for malaria programming efforts but generating these from non-malaria surveys is not standard practice. Malaria prevalence estimates for 6-59-month-old Nigerian children were compared between two national household surveys performed simultaneously in 2018: a Demographic and Health Survey (DHS) and the Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS). DHS tested via microscopy (n = 8298) and HRP2-based rapid diagnostic test (RDT, n = 11,351), and NAIIS collected dried blood spots (DBS) which were later tested for histidine-rich protein 2 (HRP2) antigen (n = 8029). National Plasmodium falciparum prevalence was 22.6% (95% CI 21.2- 24.1%) via microscopy and 36.2% (34.6- 37.8%) via RDT according to DHS, and HRP2 antigenemia was 38.3% (36.7-39.9%) by NAIIS DBS. Between the two surveys, significant rank-order correlation occurred for state-level malaria prevalence for RDT (Rho = 0.80, p < 0.001) and microscopy (Rho = 0.75, p < 0.001) versus HRP2. RDT versus HRP2 positivity showed 24 states (64.9%) with overlapping 95% confidence intervals from the two independent surveys. P. falciparum prevalence estimates among 6-59-month-olds in Nigeria were highly concordant from two simultaneous, independently conducted household surveys, regardless of malaria test utilized. This provides evidence for the value of post-hoc laboratory HRP2 detection to leverage non-malaria surveys with similar sampling designs to obtain accurate P. falciparum estimates. |
Results from the second WHO external quality assessment for the molecular detection of respiratory syncytial virus, 2019-2020.
Williams T , Jackson S , Barr I , Bi S , Bhiman J , Ellis J , von Gottberg A , Lindstrom S , Peret T , Rughooputh S , Viegas M , Hirve S , Zambon M , Zhang W , Dia N , Razanazatovo N , Al-Nabet Admh , Abubakar A , Tivane A , Barakat A , Naguib A , Aziz A , Vicari A , Moen A , Govindakarnavar A , Hall A , Darmaa B , Nathalie B , Herring B , Caetano BC , Whittaker B , Baumeister E , Nakouné E , Guthrie E , Inbanathan F , Nair H , Campbell H , Kadjo HA , Oumzil H , Heraud JM , Mott JA , Namulondo J , Leite J , Nahapetyan K , Al Ariqi L , Gazo MHI , Chadha M , Pisareva M , Venter M , Siqueira MM , Lumandas M , Niang M , Albuaini M , Salman M , Oberste S , Srikantiah P , Tang P , Couto P , Smith P , Coyle PV , Dussart P , Nguyen PN , Okada PA , Wijesinghe PR , Samuel R , Brown R , Pebody R , Fasce R , Jha R , Lindstrom S , Gerber S , Potdar V , Dong X , Deng YM . Influenza Other Respir Viruses 2023 17 (1) e13073 ![]() ![]() Background: External quality assessments (EQAs) for the molecular detection of human respiratory syncytial virus (RSV) are necessary to ensure the standardisation of reliable results. The Phase II, 2019–2020 World Health Organization (WHO) RSV EQA included 28 laboratories in 26 countries. The EQA panel evaluated performance in the molecular detection and subtyping of RSV-A and RSV-B. This manuscript describes the preparation, distribution, and analysis of the 2019–2020 WHO RSV EQA. Methods: Panel isolates underwent whole genome sequencing and in silico primer matching. The final panel included nine contemporary, one historical virus and two negative controls. The EQA panel was manufactured and distributed by the UK National External Quality Assessment Service (UK NEQAS). National laboratories used WHO reference assays developed by the United States Centers for Disease Control and Prevention, an RSV subtyping assay developed by the Victorian Infectious Diseases Reference Laboratory (Australia), or other in-house or commercial assays already in use at their laboratories. Results: An in silico analysis of isolates showed a good match to assay primer/probes. The panel was distributed to 28 laboratories. Isolates were correctly identified in 98% of samples for detection and 99.6% for subtyping. Conclusions: The WHO RSV EQA 2019–2020 showed that laboratories performed at high standards. Updating the composition of RSV molecular EQAs with contemporary strains to ensure representation of circulating strains, and ensuring primer matching with EQA panel viruses, is advantageous in assessing diagnostic competencies of laboratories. Ongoing EQAs are recommended because of continued evolution of mismatches between current circulating strains and existing primer sets. © 2023 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd. |
Comparison of one single-antigen assay and three multi-antigen SARS-CoV-2 IgG assays in Nigeria
Iriemenam NC , Ige FA , Greby SM , Okunoye OO , Uwandu M , Aniedobe M , Nwaiwu SO , Mba N , Okoli M , William NE , Ehoche A , Mpamugo A , Mitchell A , Stafford KA , Thomas AN , Olaleye T , Akinmulero OO , Agala NP , Abubakar AG , Owens A , Gwyn SE , Rogier E , Udhayakumar V , Steinhardt LC , Martin DL , Okoye MI , Audu R . J Clin Virol Plus 2023 3 (1) 100139 OBJECTIVES: Determining an accurate estimate of SARS-CoV-2 seroprevalence has been challenging in African countries where malaria and other pathogens are endemic. We compared the performance of one single-antigen assay and three multi-antigen SARS-CoV-2 IgG assays in a Nigerian population endemic for malaria. METHODS: De-identified plasma specimens from SARS-CoV-2 RT-PCR positive, dried blood spot (DBS) SARS-CoV-2 RT-PCR positive, and pre-pandemic negatives were used to evaluate the performance of the four SARS-CoV-2 assays (Tetracore, SARS2MBA, RightSign, xMAP). RESULTS: Results showed higher sensitivity with the multi-antigen (81% (Tetracore), 96% (SARS2MBA), 85% (xMAP)) versus the single-antigen (RightSign (64%)) SARS-CoV-2 assay. The overall specificities were 98% (Tetracore), 100% (SARS2MBA and RightSign), and 99% (xMAP). When stratified based on <15 days to ≥15 days post-RT-PCR confirmation, the sensitivities increased from 75% to 88.2% for Tetracore; from 93% to 100% for the SARS2MBA; from 58% to 73% for RightSign; and from 83% to 88% for xMAP. With DBS, there was no positive increase after 15-28 days for the three assays (Tetracore, SARS2MBA, and xMAP). CONCLUSION: Multi-antigen assays performed well in Nigeria, even with samples with known malaria reactivity, and might provide more accurate measures of COVID-19 seroprevalence and vaccine efficacy. |
Development of a road map to scale up the uptake and utilization of influenza vaccine in 22 countries of Eastern Mediterranean Region
Chughtai AA , Mohammed S , AlAriqi L , McCarron M , Bresee J , Abubakar A , Khan W . Vaccine 2022 40 (45) 6558-6565 BACKGROUND: The aim of this project was to develop a road map to support countries in Eastern Mediterranean Region in developing and implementing evidence-based seasonal influenza vaccination policy, strengthen influenza vaccination delivery program and address vaccine misperceptions and hesitancy. METHODS: The road map was developed through consultative meetings with countries' focal points, review of relevant literature and policy documents and analysis of WHO/UNICEF Joint Reporting Form on immunization ((JRF 2015-2020) data. Countries were categorised into three groups, based on the existence of influenza vaccination policy and national regulatory authority, availability of influenza vaccine in the country and number of influenza vaccine doses distributed/ 1000 population. The final road map was shared with representatives of all countries in Eastern Mediterranean Region and other stakeholders during a meeting in September 2021. RESULT: The goal for next 5years is to increase access to and use of utilization of seasonal influenza vaccine in Eastern Mediterranean Region to reduce influenza-associated morbidity and mortality among priority groups for vaccination. Countries in the Eastern Mediterranean Region are at different stages of implementation of the influenza vaccination program, so activities are planned under four strategic priority areas based on current situations in countries. The consultative body recommended that some countries should establish a new seasonal influenza vaccination programme and ensure the availability of vaccines, while other countries need to reduce vaccine hesitancy and enhance current seasonal influenza vaccination coverage, particularly in all high-risk groups. Countries are also encouraged to leverage COVID-19 adult vaccination programs to improve seasonal influenza vaccine uptake. CONCLUSION: This road map was developed through a consultative process to scale up the uptake and utilization of influenza vaccine in all countries of Eastern Mediterranean Region. The road map proposes activities that should be adopted in the local context to develop/ update national policies and programs. |
Seroprevalence of SARS-CoV-2 in four states of Nigeria in October 2020: a population-based household survey
Audu RA , Stafford KA , Steinhardt L , Musa ZA , Iriemenam N , Ilori E , Blanco N , Mitchell A , Hamada Y , Moloney M , Iwara E , Abimiku A , Ige FA , William NE , Igumbor E , Ochu C , Omoare AA , Okunoye O , Greby SM , Rangaka MX , Copas A , Dalhatu I , Abubakar I , McCracken S , Alagi M , Mba N , Anthony A , Okoye M , Okoi C , Ezechi OC , Salako BL , Ihekweazu C . PLoS Glob Public Health 2022 2 (6) e0000363 The observed epidemiology of SARS-CoV-2 in sub-Saharan Africa has varied greatly from that in Europe and the United States, with much lower reported incidence. Population-based studies are needed to estimate true cumulative incidence of SARS-CoV-2 to inform public health interventions. This study estimated SARS-CoV-2 seroprevalence in four selected states in Nigeria in October 2020. We implemented a two-stage cluster sample household survey in four Nigerian states (Enugu, Gombe, Lagos, and Nasarawa) to estimate age-stratified prevalence of SARS-CoV-2 antibodies. All individuals in sampled households were eligible for interview, blood draw, and nasal/oropharyngeal swab collection. We additionally tested participants for current/recent malaria infection. Seroprevalence estimates were calculated accounting for the complex survey design. Across all four states, 10,629 (96.5%) of 11,015 interviewed individuals provided blood samples. The seroprevalence of SARS-CoV- 2 antibodies was 25.2% (95% CI 21.8-28.6) in Enugu State, 9.3% (95% CI 7.0-11.5) in Gombe State, 23.3% (95% CI 20.5-26.4) in Lagos State, and 18.0% (95% CI 14.4-21.6) in Nasarawa State. Prevalence of current/recent malaria infection ranged from 2.8% in Lagos to 45.8% in Gombe and was not significantly related to SARS-CoV-2 seroprevalence. The prevalence of active SARS-CoV-2 infection in the four states during the survey period was 0.2% (95% CI 0.1-0.4). Approximately eight months after the first reported COVID-19 case in Nigeria, seroprevalence indicated infection levels 194 times higher than the 24,198 officially reported COVID-19 cases across the four states; however, most of the population remained susceptible to COVID-19 in October 2020. |
Performance of SARS-CoV-2 Antigens in a Multiplex Bead Assay for Integrated Serological Surveillance of Neglected Tropical and Other Diseases.
Gwyn S , Abubakar A , Akinmulero O , Bergeron E , Blessing UN , Chaitram J , Coughlin MM , Dawurung AB , Dickson FN , Esiekpe M , Evbuomwan E , Greby SM , Iriemenam NC , Kainulainen MH , Naanpoen TA , Napoloen L , Odoh I , Okoye M , Olaleye T , Schuh AJ , Owen SM , Samuel A , Martin DL . Am J Trop Med Hyg 2022 107 (2) 260-7 ![]() ![]() Serosurveillance can provide estimates of population-level exposure to infectious pathogens and has been used extensively during the COVID-19 pandemic. Simultaneous, serological testing for multiple pathogens can be done using bead-based immunoassays to add value to disease-specific serosurveys. We conducted a validation of four SARS-CoV-2 antigens-full-length spike protein, two receptor binding domain proteins, and the nucleocapsid protein-on our existing multiplex bead assay (MBA) for enteric diseases, malaria, and vaccine preventable diseases. After determining the optimal conditions for coupling the antigens to microsphere beads, the sensitivity and specificity of the assay were determined on two instruments (Luminex-200 and MAGPIX) when testing singly (monoplex) versus combined (multiplex). Sensitivity was assessed using plasma from 87 real-time reverse transcription polymerase chain reaction (rRT-PCR) positive persons collected in March-May of 2020 and ranged from 94.3% to 96.6% for the different testing conditions. Specificity was assessed using 98 plasma specimens collected prior to December 2019 and plasma from 19 rRT-PCR negative persons and ranged from 97.4% to 100%. The positive percent agreement was 93.8% to 97.9% using 48 specimens collected > 21 days post-symptom onset, while the negative percent agreement was ≥ 99% for all antigens. Test performance was similar using monoplex or multiplex testing. Integrating SARS-CoV-2 serology with other diseases of public health interest could add significant value to public health programs that have suffered severe programmatic setbacks during the COVID-19 pandemic. |
Validation of xMAP SARS-CoV-2 Multi-Antigen IgG assay in Nigeria.
Iriemenam NC , Ige FA , Greby SM , Mpamugo A , Abubakar AG , Dawurung AB , Esiekpe MK , Thomas AN , Okoli MU , Awala SS , Ugboaja BN , Achugbu CC , Odoh I , Nwatu FD , Olaleye T , Akayi L , Akinmulero OO , Dattijo J , Onokevbagbe E , Okunoye O , Mba N , Agala NP , Uwandu M , Aniedobe M , Stafford KA , Abimiku A , Hamada Y , Swaminathan M , Okoye MI , Steinhardt LC , Audu R . PLoS One 2022 17 (4) e0266184 ![]() OBJECTIVE: There is a need for reliable serological assays to determine accurate estimates of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) seroprevalence. Most single target antigen assays have shown some limitations in Africa. To assess the performance of a multi-antigen assay, we evaluated a commercially available SARS-CoV-2 Multi-Antigen IgG assay for human coronavirus disease 2019 (COVID-19) in Nigeria. METHODS: Validation of the xMAP SARS-CoV-2 Multi-Antigen IgG assay was carried out using well-characterized SARS-CoV-2 reverse transcription polymerase chain reactive positive (97) and pre-COVID-19 pandemic (86) plasma panels. Cross-reactivity was assessed using pre-COVID-19 pandemic plasma specimens (213) from the 2018 Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS). RESULTS: The overall sensitivity of the xMAP SARS-CoV-2 Multi-Antigen IgG assay was 75.3% [95% CI: 65.8%- 82.8%] and specificity was 99.0% [95% CI: 96.8%- 99.7%]. The sensitivity estimate increased to 83.3% [95% CI: 70.4%- 91.3%] for specimens >14 days post-confirmation of diagnosis. However, using the NAIIS pre-pandemic specimens, the false positivity rate was 1.4% (3/213). CONCLUSIONS: Our results showed overall lower sensitivity and a comparable specificity with the manufacturer's validation. There appears to be less cross-reactivity with NAIIS pre-pandemic COVID-19 specimens using the xMAP SARS-CoV-2 Multi-Antigen IgG assay. In-country SARS-CoV-2 serology assay validation can help guide the best choice of assays in Africa. |
Validation of Commercial SARS-CoV-2 Immunoassays in a Nigerian Population.
Ige F , Hamada Y , Steinhardt L , Iriemenam NC , Uwandu M , Greby SM , Aniedobe M , Salako BL , Rangaka MX , Abubakar I , Audu R . Microbiol Spectr 2021 9 (2) e0068021 ![]() Validated assays are essential for reliable serosurveys; however, most SARS-CoV-2 immunoassays have been validated using specimens from China, Europe, or U.S. populations. We evaluated the performance of five commercial SARS-CoV-2 immunoassays to inform their use in serosurveys in Nigeria. Four semiquantitative enzyme-linked immunosorbent assays (ELISAs) (Euroimmun anti-SARS-CoV-2 nucleocapsid protein [NCP] immunoglobulin G [IgG], Euroimmun spike SARS-CoV-2 IgG, Mologic Omega COVID-19 IgG, Bio-Rad Platelia SARS-CoV-2 Total Ab) and one chemiluminescent microparticle immunoassay (Abbott Architect SARS-CoV-2 IgG) were evaluated. We estimated the analytical performance characteristics using plasma from 100 SARS-CoV-2 PCR-positive patients from varied time points post-PCR confirmation and 100 prepandemic samples (50 HIV positive and 50 hepatitis B positive). The Bio-Rad assay failed the manufacturer-specified validation steps. The Euroimmun NCP, Euroimmun spike, and Mologic assays had sensitivities of 73.7%, 74.4%, and 76.9%, respectively, on samples taken 15 to 58 days after PCR confirmation and specificities of 97%, 100%, and 83.8%, respectively. The Abbott assay had 71.3% sensitivity and 100% specificity on the same panel. Parallel or serial algorithms combining two tests did not substantially improve the sensitivity or specificity. Our results showed lower sensitivity and, for one immunoassay, lower specificity compared to the manufacturers' results and other reported validations. Seroprevalence estimates using these assays might need to be interpreted with caution in Nigeria and similar settings. These findings highlight the importance of in-country validations of SARS-CoV-2 serological assays prior to use to ensure that accurate results are available for public health decision-making to control the COVID-19 pandemic in Africa. IMPORTANCE This study used positive and negative sample panels from Nigeria to test the performance of several commercially available SARS-CoV-2 serological assays. Using these prepandemic and SARS-CoV-2-positive samples, we found much lower levels of sensitivity in four commercially available assays than most assay manufacturer reports and independent evaluations. The use of these assays with suboptimal sensitivity and specificity in Nigeria or countries with population exposure to similar endemic pathogens could lead to a biased estimate of the seroprevalence, over- or underestimating the true disease prevalence, and limit efforts to stop the spread of SARS-CoV-2. It is important to conduct in-country validations of serological SARS-CoV-2 assays prior to their widespread use, especially in countries with limited representation in published assay validations. |
Considerations for quality assurance of multiplex malaria antigen detection assays with large sample sets
Alvarado R , van den Hoogen LL , Iriemenam NC , Akinmulero OO , Thomas AN , Tamunonengiyeofori I , Erasogie E , Chimaoge AC , Dawurung AB , Esiekpe MK , Okoli MU , Mba N , Ogunniyi A , Abimiku A , Maire M , Bassey OO , Okoye M , Swaminathan M , Greby SM , Ndodo N , Ihekweazu C , Abubakar A , Steinhardt L , Rogier E . Sci Rep 2021 11 (1) 13248 Multiplex assays for malaria antigen detection can gather data from large sample sets, but considerations for the consistency and quality assurance (QA) of mass testing lack evaluation. We present a QA framework for a study occurring November 2019 to March 2020 involving 504 assay plates detecting four Plasmodium antigens: pan-Plasmodium aldolase and lactate dehydrogenase (LDH), histidine-rich protein 2 (HRP2), P. vivax LDH (PvLDH). Controls on each plate included buffer blank, antigen negative blood, and 4-point positive dilution curve. The blank and negative blood provided consistently low signal for all targets except for pAldolase, which showed variability. Positive curve signals decreased throughout the 5-month study duration but retained a coefficient of variation (CV) of < 5%, with the exception of HRP2 in month 5 (CV of 11%). Regression fittings for inter-plate control signals provided mean and standard deviations (SDs), and of 504 assay plates, 6 (1.2%) violated the acceptable deviation limits and were repeated. For the 40,272 human blood samples assayed in this study, of 161,088 potential data points (each sample × 4 antigens), 160,641 (99.7%) successfully passed quality checks. The QA framework presented here can be utilized to ensure quality of laboratory antigen detection for large sample sets. |
Cross-reactivity of two SARS-CoV-2 serological assays in a malaria-endemic setting.
Steinhardt LC , Ige F , Iriemenam NC , Greby SM , Hamada Y , Uwandu M , Aniedobe M , Stafford KA , Abimiku A , Mba N , Agala N , Okunoye O , Mpamugo A , Swaminathan M , Onokevbagbe E , Olaleye T , Odoh I , Marston BJ , Okoye M , Abubakar I , Rangaka MX , Rogier E , Audu R . J Clin Microbiol 2021 59 (7) e0051421 Background: Accurate SARS-CoV-2 serological assays are critical for COVID-19 serosurveillance. However, previous studies have indicated possible cross-reactivity of these assays, including in malaria-endemic areas.Methods: We tested 213 well-characterized pre-pandemic samples from Nigeria using two SARS-CoV-2 serological assays: Abbott Architect IgG and Euroimmun NCP IgG assay, both targeting SARS-CoV-2 nucleocapsid protein. To assess antibody binding strength, an avidity assay was performed on these samples and on plasma from SARS-CoV-2 PCR-positive persons.Results: Thirteen (6.1%) of 212 samples run on the Abbott assay and 38 (17.8%) of 213 run on the Euroimmun assay were positive. Anti-Plasmodium IgG levels were significantly higher among false-positives for both Abbott and Euroimmun; no association was found with active P. falciparum infection. An avidity assay using various concentratIons of urea wash in the Euroimmun assay reduced loosely-bound IgG: of 37 positive/borderline pre-pandemic samples, 46%, 86%, 89%, and 97% became negative using 2M, 4M, 5M, and 8M urea washes, respectively. The wash slightly reduced avidity of antibodies from SARS-CoV-2 patients within 28 days of PCR confirmation; thereafter avidity increased for all urea concentrations except 8M.Conclusions: This validation found moderate to substantial cross-reactivity on two SARS-CoV-2 serological assays using samples from a malaria-endemic setting. A simple urea wash appeared to alleviate issues of cross-reactivity. |
Lessons from co-production of evidence and policy in Nigeria's COVID-19 response.
Abubakar I , Dalglish SL , Ihekweazu CA , Bolu O , Aliyu SH . BMJ Glob Health 2021 6 (3) In February 2020, Nigeria faced a potentially catastrophic COVID-19 outbreak due to multiple introductions, high population density in urban slums, prevalence of other infectious diseases and poor health infrastructure. As in other countries, Nigerian policymakers had to make rapid and consequential decisions with limited understanding of transmission dynamics and the efficacy of available control measures. We present an account of the Nigerian COVID-19 response based on co-production of evidence between political decision-makers, health policymakers and academics from Nigerian and foreign institutions, an approach that allowed a multidisciplinary group to collaborate on issues arising in real time. Key aspects of the process were the central role of policymakers in determining priority areas and the coordination of multiple, sometime conflicting inputs from stakeholders to write briefing papers and inform effective national decision making. However, the co-production approach met with some challenges, including limited transparency, bureaucratic obstacles and an overly epidemiological focus on numbers of cases and deaths, arguably to the detriment of addressing social and economic effects of response measures. Larger systemic obstacles included a complex multitiered health system, fragmented decision-making structures and limited funding for implementation. Going forward, Nigeria should strengthen the integration of the national response within existing health decision bodies and implement strategies to mitigate the social and economic impact, particularly on the poorest Nigerians. The co-production of evidence examining the broader public health impact, with synthesis by multidisciplinary teams, is essential to meeting the social and public health challenges posed by the COVID-19 pandemic in Nigeria and other countries. |
Structure, function and performance of Early Warning Alert and Response Network (EWARN) in emergencies in the Eastern Mediterranean Region
Mala P , Abubakar A , Takeuchi A , Buliva E , Husain F , Malik MR , Tayyab M , Elnoserry S . Int J Infect Dis 2021 105 194-198 INTRODUCTION: The Eastern Mediterranean Region (EMR) has experienced several protracted humanitarian crises. The affected population are served by eight EWARN systems for outbreak detection and response. Our aim was to compare structure, function, and performance of the systems, adherence to current guidance, and note emerging lessons. METHODS: This study included a review of published and unpublished literature, a structured survey, and interviews. RESULTS: Findings showed all systems adhered to basic EWARN structure. Four of eight systems had electronic platforms while one was implementing. Regarding key EWARN function of outbreak detection, out of the 35 health conditions, 26 were communicable diseases and nine were non-communicable; only two systems focused on epidemic-prone diseases. Half the systems achieved ≥60% population coverage, five achieved ≥80% reporting timeliness, six achieved ≥80% reporting completeness, and seven achieved verification of ≥80% of alerts of suspected outbreaks. CONCLUSION: Findings showed that the systems followed EWARN structure while increasing adoption of electronic platforms. Performance, including timeliness and completeness of reporting, and timely verification of alerts, were optimal for most of the systems. However, population coverage was low for most of the systems, and EWARN's primary focus of outbreak detection was being undermined by increasing number of non-epidemic diseases. |
Nigeria's public health response to the COVID-19 pandemic: January to May 2020.
Dan-Nwafor C , Ochu CL , Elimian K , Oladejo J , Ilori E , Umeokonkwo C , Steinhardt L , Igumbor E , Wagai J , Okwor T , Aderinola O , Mba N , Hassan A , Dalhat M , Jinadu K , Badaru S , Arinze C , Jafiya A , Disu Y , Saleh F , Abubakar A , Obiekea C , Yinka-Ogunleye A , Naidoo D , Namara G , Muhammad S , Ipadeola O , Ofoegbunam C , Ogunbode O , Akatobi C , Alagi M , Yashe R , Crawford E , Okunromade O , Aniaku E , Mba S , Agogo E , Olugbile M , Eneh C , Ahumibe A , Nwachukwu W , Ibekwe P , Adejoro OO , Ukponu W , Olayinka A , Okudo I , Aruna O , Yusuf F , Alex-Okoh M , Fawole T , Alaka A , Muntari H , Yennan S , Atteh R , Balogun M , Waziri N , Ogunniyi A , Ebhodaghe B , Lokossou V , Abudulaziz M , Adebiyi B , Abayomi A , Abudus-Salam I , Omilabu S , Lawal L , Kawu M , Muhammad B , Tsanyawa A , Soyinka F , Coker T , Alabi O , Joannis T , Dalhatu I , Swaminathan M , Salako B , Abubakar I , Fiona B , Nguku P , Aliyu SH , Ihekweazu C . J Glob Health 2020 10 (2) 020399 The novel coronavirus disease 2019, COVID-19, which is caused by severe acute respiratory syndrome virus 2 (SARS-CoV-2) [1] was first reported in December 2019 by Chinese Health Authorities following an outbreak of pneumonia of unknown origin in Wuhan, Hubei Province [2,3]. SARS-CoV-2 is likely of zoonotic origin, similar to SARS and Middle East Respiratory Syndrome (MERS), and transmitted between humans through respiratory droplets and fomites. Since its emergence, it has rapidly spread globally [4]. |
Systems thinking for health emergencies: use of process mapping during outbreak response
Durski KN , Naidoo D , Singaravelu S , Shah AA , Djingarey MH , Formenty P , Ihekweazu C , Banjura J , Kebela B , Yinka-Ogunleye A , Fall IS , Eteng W , Vandi M , Keimbe C , Abubakar A , Mohammed A , Williams DE , Lamunu M , Briand S , Changa Changa JC , Minkoulou E , Jernigan D , Lubambo D , Khalakdina A , Mamadu I , Talisuna A , Mbule Kadiobo A , Jambai A , Aylward B , Osterholm M . BMJ Glob Health 2020 5 (10) Process mapping is a systems thinking approach used to understand, analyse and optimise processes within complex systems. We aim to demonstrate how this methodology can be applied during disease outbreaks to strengthen response and health systems. Process mapping exercises were conducted during three unique emerging disease outbreak contexts with different: mode of transmission, size, and health system infrastructure. System functioning improved considerably in each country. In Sierra Leone, laboratory testing was accelerated from 6 days to within 24 hours. In the Democratic Republic of Congo, time to suspected case notification reduced from 7 to 3 days. In Nigeria, key data reached the national level in 48 hours instead of 5 days. Our research shows that despite the chaos and complexities associated with emerging pathogen outbreaks, the implementation of a process mapping exercise can address immediate response priorities while simultaneously strengthening components of a health system. |
Update on Extensively Drug-Resistant Salmonella Serotype Typhi Infections Among Travelers to or from Pakistan and Report of Ceftriaxone-Resistant Salmonella Serotype Typhi Infections Among Travelers to Iraq - United States, 2018-2019.
Francois Watkins LK , Winstead A , Appiah GD , Friedman CR , Medalla F , Hughes MJ , Birhane MG , Schneider ZD , Marcenac P , Hanna SS , Godbole G , Walblay KA , Wiggington AE , Leeper M , Meservey EH , Tagg KA , Chen JC , Abubakar A , Lami F , Asaad AM , Sabaratnam V , Ikram A , Angelo KM , Walker A , Mintz E . MMWR Morb Mortal Wkly Rep 2020 69 (20) 618-622 ![]() ![]() Ceftriaxone-resistant Salmonella enterica serotype Typhi (Typhi), the bacterium that causes typhoid fever, is a growing public health threat. Extensively drug-resistant (XDR) Typhi is resistant to ceftriaxone and other antibiotics used for treatment, including ampicillin, chloramphenicol, ciprofloxacin, and trimethoprim-sulfamethoxazole (1). In March 2018, CDC began enhanced surveillance for ceftriaxone-resistant Typhi in response to an ongoing outbreak of XDR typhoid fever in Pakistan. CDC had previously reported the first five cases of XDR Typhi in the United States among patients who had spent time in Pakistan (2). These illnesses represented the first cases of ceftriaxone-resistant Typhi documented in the United States (3). This report provides an update on U.S. cases of XDR typhoid fever linked to Pakistan and describes a new, unrelated cluster of ceftriaxone-resistant Typhi infections linked to Iraq. Travelers to areas with endemic Typhi should receive typhoid vaccination before traveling and adhere to safe food and water precautions (4). Treatment of patients with typhoid fever should be guided by antimicrobial susceptibility testing whenever possible (5), and clinicians should consider travel history when selecting empiric therapy. |
Improved capacity for influenza surveillance in the WHO Eastern Mediterranean Region: Progress in a challenging setting
Malik MR , Abubakar A , Kholy AE , Buliva E , Khan WM , Lamichhane J , Moen A , McCarron M , Zureick K , Obtel M . J Infect Public Health 2019 13 (3) 391-401 BACKGROUND: The World Health Organization Regional Office for Eastern Mediterranean has partnered with the United States Centers for Disease Control and Prevention (CDC) to strengthen pandemic influenza preparedness and response in the Region since 2006. This partnership focuses on pandemic preparedness planning, establishing and enhancing influenza surveillance systems, improving laboratory capacity for detection of influenza viruses, estimating the influenza disease burden, and providing evidence to support policies for the introduction and increased use of seasonal influenza vaccines. METHODS: Various published and unpublished data from public and WHO sources, programme indicators of the CDC cooperative agreement and Pandemic Influenza Preparedness Framework were reviewed and analysed. Analyses and review of the programme indicators and published articles enabled us to generate information that was unavailable from only WHO sources. RESULTS: Most (19/22) countries of the Region have established influenza surveillance system; 16 countries in the Region have designated National Influenza Centres. The Region has seen considerable improvement in geographic coverage of influenza surveillance and influenza detection. Virus sharing has improved and almost all of the participating laboratories have achieved a 100% efficiency score in the WHO external quality assessment programme. At least seven countries have estimated their influenza disease burden using surveillance data and at least 17 are now using seasonal influenza vaccines as a control strategy for influenza illness. CONCLUSION: The Region has achieved substantial progress in surveillance and response to seasonal influenza, despite the adverse effects to the health systems of many countries due to acute and protracted emergencies and other significant challenges. |
Progression from latent infection to active disease in dynamic tuberculosis transmission models: a systematic review of the validity of modelling assumptions
Menzies NA , Wolf E , Connors D , Bellerose M , Sbarra AN , Cohen T , Hill AN , Yaesoubi R , Galer K , White PJ , Abubakar I , Salomon JA . Lancet Infect Dis 2018 18 (8) e228-e238 Mathematical modelling is commonly used to evaluate infectious disease control policy and is influential in shaping policy and budgets. Mathematical models necessarily make assumptions about disease natural history and, if these assumptions are not valid, the results of these studies can be biased. We did a systematic review of published tuberculosis transmission models to assess the validity of assumptions about progression to active disease after initial infection (PROSPERO ID CRD42016030009). We searched PubMed, Web of Science, Embase, Biosis, and Cochrane Library, and included studies from the earliest available date (Jan 1, 1962) to Aug 31, 2017. We identified 312 studies that met inclusion criteria. Predicted tuberculosis incidence varied widely across studies for each risk factor investigated. For population groups with no individual risk factors, annual incidence varied by several orders of magnitude, and 20-year cumulative incidence ranged from close to 0% to 100%. A substantial proportion of modelled results were inconsistent with empirical evidence: for 10-year cumulative incidence, 40% of modelled results were more than double or less than half the empirical estimates. These results demonstrate substantial disagreement between modelling studies on a central feature of tuberculosis natural history. Greater attention to reproducing known features of epidemiology would strengthen future tuberculosis modelling studies, and readers of modelling studies are recommended to assess how well those studies demonstrate their validity. |
Capacity strengthening through pre-migration tuberculosis screening programmes: IRHWG experiences
Douglas P , Posey DL , Zenner D , Robson J , Abubakar I , Giovinazzo G . Int J Tuberc Lung Dis 2017 21 (7) 737-745 Effective tuberculosis (TB) prevention and care for migrants requires population health-based approaches that treat the relationship between migration and health as a progressive, interactive process influenced by many variables and addressed as far upstream in the process as possible. By including capacity building in source countries, pre-migration medical screening has the potential to become an integral component of public health promotion, as well as infection and disease prevention, in migrant-receiving nations, while simultaneously increasing capabilities in countries of origin. This article describes the collaborative experiences of five countries (Australia, Canada, New Zealand, United Kingdom and the United States of America, members of the Immigration and Refugee Health Working Group [IRHWG]), with similar pre-migration screening programmes for TB that are mandated. Qualitative examples of capacity building through IRHWG programmes are provided. Combined, the IRHWG member countries screen approximately 2 million persons overseas every year. Large-scale pre-entry screening programmes undertaken by IRHWG countries require building additional capacity for health care providers, radiology facilities and laboratories. This has resulted in significant improvements in laboratory and treatment capacity, providing availability of these facilities for national public health programmes. As long as global health disparities and disease prevalence differentials exist, national public health programmes and policies in migrant-receiving nations will continue to be challenged to manage the diseases prevalent in these migrating populations. National TB programmes and regulatory systems alone will not be able to achieve TB elimination. The management of health issues resulting from population mobility will require integration of national and global health initiatives which, as demonstrated here, can be supported through the capacity-building endeavours of pre-migration screening programmes. |
Immigrant arrival and tuberculosis among large immigrant- and refugee-receiving countries, 2005-2009
White Z , Painter J , Douglas P , Abubakar I , Njoo H , Archibald C , Halverson J , Robson J , Posey DL . Tuberc Res Treat 2017 2017 8567893 Objective. Tuberculosis control in foreign-born populations is a major public health concern for Australia, Canada, New Zealand, United Kingdom, and the United States, large immigrant- and refugee-receiving countries that comprise the Immigration and Refugee Health Working Group (IRHWG). Identifying and comparing immigration and distribution of foreign-born tuberculosis cases are important for developing targeted and collaborative interventions. Methods. Data stratified by year and country of birth from 2005 to 2009 were received from these five countries. Immigration totals, tuberculosis case totals, and multidrug-resistant tuberculosis (MDR TB) case totals from source countries were analyzed and compared to reveal similarities and differences for each member of the group. Results. Between 2005 and 2009, there were a combined 31,785,002 arrivals, 77,905 tuberculosis cases, and 888 MDR TB cases notified at the federal level in the IRHWG countries. India, China, Vietnam, and the Philippines accounted for 41.4% of the total foreign-born tuberculosis cases and 42.7% of the foreign-born MDR tuberculosis cases to IRHWG. Interpretation. Collaborative efforts across a small number of countries have the potential to yield sizeable gains in tuberculosis control for these large immigrant- and refugee-receiving countries. |
The global burden of viral hepatitis from 1990 to 2013: findings from the Global Burden of Disease Study 2013
Stanaway JD , Flaxman AD , Naghavi M , Fitzmaurice C , Vos T , Abubakar I , Abu-Raddad LJ , Assadi R , Bhala N , Cowie B , Forouzanfour MH , Groeger J , Hanafiah KM , Jacobsen KH , James SL , MacLachlan J , Malekzadeh R , Martin NK , Mokdad AA , Mokdad AH , Murray CJ , Plass D , Rana S , Rein DB , Richardus JH , Sanabria J , Saylan M , Shahraz S , So S , Vlassov VV , Weiderpass E , Wiersma ST , Younis M , Yu C , El Sayed Zaki M , Cooke GS . Lancet 2016 388 (10049) 1081-1088 BACKGROUND: With recent improvements in vaccines and treatments against viral hepatitis, an improved understanding of the burden of viral hepatitis is needed to inform global intervention strategies. We used data from the Global Burden of Disease (GBD) Study to estimate morbidity and mortality for acute viral hepatitis, and for cirrhosis and liver cancer caused by viral hepatitis, by age, sex, and country from 1990 to 2013. METHODS: We estimated mortality using natural history models for acute hepatitis infections and GBD's cause-of-death ensemble model for cirrhosis and liver cancer. We used meta-regression to estimate total cirrhosis and total liver cancer prevalence, as well as the proportion of cirrhosis and liver cancer attributable to each cause. We then estimated cause-specific prevalence as the product of the total prevalence and the proportion attributable to a specific cause. Disability-adjusted life-years (DALYs) were calculated as the sum of years of life lost (YLLs) and years lived with disability (YLDs). FINDINGS: Between 1990 and 2013, global viral hepatitis deaths increased from 0.89 million (95% uncertainty interval [UI] 0.86-0.94) to 1.45 million (1.38-1.54); YLLs from 31.0 million (29.6-32.6) to 41.6 million (39.1-44.7); YLDs from 0.65 million (0.45-0.89) to 0.87 million (0.61-1.18); and DALYs from 31.7 million (30.2-33.3) to 42.5 million (39.9-45.6). In 2013, viral hepatitis was the seventh (95% UI seventh to eighth) leading cause of death worldwide, compared with tenth (tenth to 12th) in 1990. INTERPRETATION: Viral hepatitis is a leading cause of death and disability worldwide. Unlike most communicable diseases, the absolute burden and relative rank of viral hepatitis increased between 1990 and 2013. The enormous health loss attributable to viral hepatitis, and the availability of effective vaccines and treatments, suggests an important opportunity to improve public health. FUNDING: Bill & Melinda Gates Foundation. |
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