Last data update: May 06, 2024. (Total: 46732 publications since 2009)
Records 1-18 (of 18 Records) |
Query Trace: Roels T[original query] |
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Effects of COVID-19 pandemic on voluntary medical male circumcision services for HIV prevention, Sub-Saharan Africa, 2020
Peck ME , Ong KS , Lucas T , Prainito A , Thomas AG , Brun A , Kiggundu V , Yansaneh A , Busang L , Kgongwana K , Kelaphile D , Seipone K , Letebele MH , Makadzange PF , Marwiro A , Sesinyi M , Lapidos T , Lukhele N , Maziya V , Mkhontfo M , Gultie T , Mulatu D , Shimelis M , Zegeye T , Teka T , Bulterys M , Njenga JN , Odoyo-June E , Juma AW , Soo L , Talam N , Brown M , Chakare T , Nonyana N , Khoabane MA , Auld AF , Maida A , Msungama W , Kapito M , Nyirenda R , Matchere F , Odek J , Canda M , Malimane I , Come J , Gaspar N , Langa A , Aupokolo MA , Vejorerako KC , Kahindi L , Mali D , Zegeye A , Mangoya D , Zemburuka BL , Bamwesigye J , Kankindi I , Kayirangwa E , Malamba SS , Roels T , Kayonde L , Zimulinda E , Ndengo E , Nsanzimana S , Remera E , Rwibasira GN , Sangwayire B , Semakula M , Rugira E , Rugwizangoga E , Tubane E , Yoboka E , Lawrence J , Loykissoonlal D , Maphothi N , Achut V , Bunga S , Moi M , Amuri M , Kazaura K , Simbeye D , Fida N , Kayange AA , Seleman M , Akao J , Alamo ST , Kabuye G , Kyobutungi S , Makumbi FE , Mudiope P , Nantez B , Chituwo O , Godfrey L , Muyunda B , Kamboyi R , Masiye J , Lifuka E , Mandisarisa J , Mhangara M , Xaba S , Toledo C . Emerg Infect Dis 2022 28 (13) S262-s269 Beginning in March 2020, to reduce COVID-19 transmission, the US President's Emergency Plan for AIDS Relief supporting voluntary medical male circumcision (VMMC) services was delayed in 15 sub-Saharan African countries. We reviewed performance indicators to compare the number of VMMCs performed in 2020 with those performed in previous years. In all countries, the annual number of VMMCs performed decreased 32.5% (from 3,898,960 in 2019 to 2,631,951 in 2020). That reduction is largely attributed to national and local COVID-19 mitigation measures instituted by ministries of health. Overall, 66.7% of the VMMC global annual target was met in 2020, compared with 102.0% in 2019. Countries were not uniformly affected; South Africa achieved only 30.7% of its annual target in 2020, but Rwanda achieved 123.0%. Continued disruption to the VMMC program may lead to reduced circumcision coverage and potentially increased HIV-susceptible populations. Strategies for modifying VMMC services provide lessons for adapting healthcare systems during a global pandemic. |
Safety and immunogenicity of two novel type 2 oral poliovirus vaccine candidates compared with a monovalent type 2 oral poliovirus vaccine in healthy adults: two clinical trials.
De Coster I , Leroux-Roels I , Bandyopadhyay AS , Gast C , Withanage K , Steenackers K , De Smedt P , Aerssens A , Leroux-Roels G , Oberste MS , Konopka-Anstadt JL , Weldon WC , Fix A , Konz J , Wahid R , Modlin J , Clemens R , Costa Clemens SA , Bachtiar NS , Van Damme P . Lancet 2020 397 (10268) 39-50 BACKGROUND: Two novel type 2 oral poliovirus vaccine (OPV2) candidates, novel OPV2-c1 and novel OPV2-c2, designed to be more genetically stable than the licensed Sabin monovalent OPV2, have been developed to respond to ongoing polio outbreaks due to circulating vaccine-derived type 2 polioviruses. METHODS: We did two randomised studies at two centres in Belgium. The first was a phase 4 historical control study of monovalent OPV2 in Antwerp, done before global withdrawal of OPV2, and the second was a phase 2 study in Antwerp and Ghent with novel OPV2-c1 and novel OPV2-c2. Eligible participants were healthy adults aged 18-50 years with documented history of at least three polio vaccinations, including OPV in the phase 4 study and either OPV or inactivated poliovirus vaccine (IPV) in the novel OPV2 phase 2 study, with no dose within 12 months of study start. In the historical control trial, participants were randomly assigned to either one dose or two doses of monovalent OPV2. In the novel OPV2 trial, participants with previous OPV vaccinations were randomly assigned to either one or two doses of novel OPV2-c1 or to one or two doses of novel OPV2-c2. IPV-vaccinated participants were randomly assigned to receive two doses of either novel OPV2-c1, novel OPV2-c2, or placebo. Vaccine administrators were unmasked to treatment; medical staff performing safety and reactogenicity assessments or blood draws for immunogenicity assessments were masked. Participants received the first vaccine dose on day 0, and a second dose on day 28 if assigned to receive a second dose. Primary objectives were assessments and comparisons of safety up to 28 days after each dose, including solicited adverse events and serious adverse events, and immunogenicity (seroprotection rates on day 28 after the first vaccine dose) between monovalent OPV2 and the two novel OPV2 candidates. Primary immunogenicity analyses were done in the per-protocol population. Safety was assessed in the total vaccinated population-ie, all participants who received at least one dose of their assigned vaccine. The phase 4 control study is registered with EudraCT (2015-003325-33) and the phase 2 novel OPV2 study is registered with EudraCT (2018-001684-22) and ClinicalTrials.gov (NCT04544787). FINDINGS: In the historical control study, between Jan 25 and March 18, 2016, 100 volunteers were enrolled and randomly assigned to receive one or two doses of monovalent OPV2 (n=50 in each group). In the novel OPV2 study, between Oct 15, 2018, and Feb 27, 2019, 200 previously OPV-vaccinated volunteers were assigned to the four groups to receive one or two doses of novel OPV2-c1 or novel OPV2-c2 (n=50 per group); a further 50 participants, previously vaccinated with IPV, were assigned to novel OPV2-c1 (n=17), novel OPV2-c2 (n=16), or placebo (n=17). All participants received the first dose of assigned vaccine or placebo and were included in the total vaccinated population. All vaccines appeared safe; no definitely vaccine-related withdrawals or serious adverse events were reported. After first doses in previously OPV-vaccinated participants, 62 (62%) of 100 monovalent OPV2 recipients, 71 (71%) of 100 recipients of novel OPV2-c1, and 74 (74%) of 100 recipients of novel OPV2-c2 reported solicited systemic adverse events, four (monovalent OPV2), three (novel OPV2-c1), and two (novel OPV2-c2) of which were considered severe. In IPV-vaccinated participants, solicited adverse events occurred in 16 (94%) of 17 who received novel OPV2-c1 (including one severe) and 13 (81%) of 16 who received novel OPV2-c2 (including one severe), compared with 15 (88%) of 17 placebo recipients (including two severe). In previously OPV-vaccinated participants, 286 (97%) of 296 were seropositive at baseline; after one dose, 100% of novel OPV2 vaccinees and 97 (97%) of monovalent OPV2 vaccinees were seropositive. INTERPRETATION: Novel OPV2 candidates were as safe, well tolerated, and immunogenic as monovalent OPV2 in previously OPV-vaccinated and IPV-vaccinated adults. These data supported the further assessment of the vaccine candidates in children and infants. FUNDING: University of Antwerp and Bill & Melinda Gates Foundation. |
Zika virus enhances monocyte adhesion and transmigration favoring viral dissemination to neural cells.
Ayala-Nunez NV , Follain G , Delalande F , Hirschler A , Partiot E , Hale GL , Bollweg BC , Roels J , Chazal M , Bakoa F , Carocci M , Bourdoulous S , Faklaris O , Zaki SR , Eckly A , Uring-Lambert B , Doussau F , Cianferani S , Carapito C , Jacobs FMJ , Jouvenet N , Goetz JG , Gaudin R . Nat Commun 2019 10 (1) 4430 Zika virus (ZIKV) invades and persists in the central nervous system (CNS), causing severe neurological diseases. However the virus journey, from the bloodstream to tissues through a mature endothelium, remains unclear. Here, we show that ZIKV-infected monocytes represent suitable carriers for viral dissemination to the CNS using human primary monocytes, cerebral organoids derived from embryonic stem cells, organotypic mouse cerebellar slices, a xenotypic human-zebrafish model, and human fetus brain samples. We find that ZIKV-exposed monocytes exhibit higher expression of adhesion molecules, and higher abilities to attach onto the vessel wall and transmigrate across endothelia. This phenotype is associated to enhanced monocyte-mediated ZIKV dissemination to neural cells. Together, our data show that ZIKV manipulates the monocyte adhesive properties and enhances monocyte transmigration and viral dissemination to neural cells. Monocyte transmigration may represent an important mechanism required for viral tissue invasion and persistence that could be specifically targeted for therapeutic intervention. |
Differences in antigenic sites and other functional regions between genotype A and G mumps virus surface proteins.
Gouma S , Vermeire T , Van Gucht S , Martens L , Hutse V , Cremer J , Rota PA , Leroux-Roels G , Koopmans M , Binnendijk RV , Vandermarliere E . Sci Rep 2018 8 (1) 13337 The surface proteins of the mumps virus, the fusion protein (F) and haemagglutinin-neuraminidase (HN), are key factors in mumps pathogenesis and are important targets for the immune response during mumps virus infection. We compared the predicted amino acid sequences of the F and HN genes from Dutch mumps virus samples from the pre-vaccine era (1957-1982) with mumps virus genotype G strains (from 2004 onwards). Genotype G is the most frequently detected mumps genotype in recent outbreaks in vaccinated communities, especially in Western Europe, the USA and Japan. Amino acid differences between the Jeryl Lynn vaccine strains (genotype A) and genotype G strains were predominantly located in known B-cell epitopes and in N-linked glycosylation sites on the HN protein. There were eight variable amino acid positions specific to genotype A or genotype G sequences in five known B-cell epitopes of the HN protein. These differences may account for the reported antigenic differences between Jeryl Lynn and genotype G strains. We also found amino acid differences in and near sites on the HN protein that have been reported to play a role in mumps virus pathogenesis. These differences may contribute to the occurrence of genotype G outbreaks in vaccinated communities. |
Implementation of a Test, Treat, and Prevent HIV program among men who have sex with men and transgender women in Thailand, 2015-2016
Ongwandee S , Lertpiriyasuwat C , Khawcharoenporn T , Chetchotisak P , Thiansukhon E , Leerattanapetch N , Leungwaranan B , Manopaiboon C , Phoorisri T , Visavakum P , Jetsawang B , Poolsawat M , Nookhai S , Vasanti-Uppapokakorn M , Karuchit S , Kittinunvorakoon C , Mock P , Prybylski D , Sukkul AC , Roels T , Martin M . PLoS One 2018 13 (7) e0201171 INTRODUCTION: Antiretroviral therapy reduces the risk of serious illness among people living with HIV and can prevent HIV transmission. We implemented a Test, Treat, and Prevent HIV Program among men who have sex with men (MSM) and transgender women at five hospitals in four provinces of Thailand to increase HIV testing, help those who test positive start antiretroviral therapy, and increase access to pre-exposure prophylaxis (PrEP). METHODS: We implemented rapid HIV testing and trained staff on immediate antiretroviral initiation at the five hospitals and offered PrEP at two hospitals. We recruited MSM and transgender women who walked-in to clinics and used a peer-driven intervention to expand recruitment. We used logistic regression to determine factors associated with prevalent HIV infection and the decision to start antiretroviral therapy and PrEP. RESULTS: During 2015 and 2016, 1880 people enrolled. Participants recruited by peers were younger (p<0.0001), less likely to be HIV-infected (p<0.0001), and those infected had higher CD4 counts (p = 0.04) than participants who walked-in to the clinics. Overall, 16% were HIV-positive: 18% of MSM and 9% of transgender women; 86% started antiretroviral therapy and 46% of eligible participants started PrEP. A higher proportion of participants at hospitals with one-stop HIV services started antiretroviral therapy than other hospitals. Participants who started PrEP were more likely to report sex with an HIV-infected partner (p = 0.002), receptive anal intercourse (p = 0.02), and receiving PrEP information from a hospital (p<0.0001). CONCLUSIONS: We implemented a Test, Treat, and Prevent HIV Program offering rapid HIV testing and immediate access to antiretroviral therapy and PrEP. Peer-driven recruitment reached people at high risk of HIV and people early in HIV illness, providing an opportunity to promote HIV prevention services including PrEP and early antiretroviral therapy. Sites with one-stop HIV services had a higher uptake of antiretroviral therapy and PrEP. |
Monitoring HIV drug resistance: Early warning indicators to assess performance of Thailand's antiretroviral treatment program
Lertpiriyasuwat C , Teeraratkul A , Suchonwanich Y , Chatharojwong N , Phokasawad K , Yuktanon P , Pattarapayoon N , Bhakeecheep S , Bertagnolio S , Roels TH , Thanprasertsuk S . J Med Assoc Thai 2017 100 (9) 944-952 Objective: To describe trends in Thailand's antiretroviral treatment (ART) program performance assessed by HIV drug resistance early warning indicators (EWIs), as recommended by WHO, between 2009 and 2013. Material and Method: Seven EWIs were monitored, viral load (VL) testing coverage, VL suppression, retention in ART, lost to follow-up (LTFU), antiretrovirals (ARVs) dispensing practices, on-time pill pick-up, and pharmacy stock-outs. Data from ART adult patients in National Health Security Office Scheme were analyzed except for pharmacy stock-outs, which were reported from hospitals. Aggregated averages were calculated for each EWI. Chi-square for trend was applied to measure significant changes. Results: By September 2013, 174,284 adults were receiving ART at 929 hospitals. Over time, improvement in VL testing coverage (53.8% in 2009 to 79.8% in 2013) was observed. VL suppression and on-time pill pick up rates were well above 90%. Rates of retention in ART declined from 84.0 to 82.9%, whereas LTFU rates increased from 8.3 to 9.2% (p<0.001). Prescriptions with inappropriate ARVs decreased from 0.32 to 0.10% (p<0.001). Of reporting hospitals, 96.1%, 96.3%, and 96.2% observed no ARVs stock-out between 2011 and 2013. Conclusion: EWI is a useful tool to monitor ART program performance and to identify area where improvement is needed. |
Validity of self-reported concentration and memory problems: Relationship with neuropsychological assessment and depression
Bowler RM , Adams SW , Schwarzer R , Gocheva VV , Roels HA , Kim Y , Kircos CL , Wright CW , Colledge M , Bollweg G , Lobdell DT . J Clin Exp Neuropsychol 2017 39 (10) 1-11 BACKGROUND: This study investigated the validity of self-reported concentration and memory problems (CMP) in residents environmentally exposed to manganese (Mn). METHOD: Self-report of CMP from a health questionnaire (HQ) and the Symptom Checklist-90-Revised (SCL-90-R) was compared to neuropsychological assessment (Trails A&B; Digit Span; Digit Symbol; Similarities; Auditory Consonant Trigrams, ACT; NAB Memory; Rey-Osterrieth, Rey-O, Delayed). Participants included 146 residents from Ohio exposed to air-Mn, with a modeled average concentration of 0.55 microg m-3 (range = 0.01-4.58). RESULTS: Residents were primarily White (94.5%), aged 30-64 years (M = 51.24), with a minimum of 10 years of residence (range = 10-64). Ninety-four (65.3%) participants reported concentration problems, and 107 residents (73.3%) reported memory problems. More participants endorsed CMP on the SCL-90-R than on the HQ. The prevalence of self-reported CMP was higher for women than for men (88.4% vs. 68.3%). Point-biserial and Pearson's correlations between self-reported CMP and neuropsychological test scores were nonsignificant and weak for both the HQ (rpb = -.20 to rpb = .04) and the SCL-90-R (r = -.12 to r = .007). Greater levels of depression, anxiety, and female sex predicted having more self-reported CMP on both the HQ and the SCL-90-R. Air-Mn and blood-Mn were not associated with self-reported CMP. Residential distance from the Mn source accounted for a small proportion of variance (sr2 = .04), although depression remained the largest predictor (sr2 = .21). CONCLUSION: These results indicate that self-report of CMP in Mn-exposed residents appear to be invalid when compared to neuropsychological test scores. The participants' misperception of having CMP is associated with less education and higher levels of depression. Neuropsychological assessment is recommended to attain valid results. |
Immunogenicity and safety of a novel monovalent high-dose inactivated poliovirus type 2 vaccine in infants: a comparative, observer-blind, randomised, controlled trial
Saez-Llorens X , Clemens R , Leroux-Roels G , Jimeno J , Clemens SA , Weldon WC , Oberste MS , Molina N , Bandyopadhyay AS . Lancet Infect Dis 2015 16 (3) 321-30 BACKGROUND: Following the proposed worldwide switch from trivalent oral poliovirus vaccine (tOPV) to bivalent types 1 and 3 OPV (bOPV) in 2016, inactivated poliovirus vaccine (IPV) will be the only source of protection against poliovirus type 2. With most countries opting for one dose of IPV in routine immunisation schedules during this transition because of cost and manufacturing constraints, optimisation of protection against all poliovirus types will be a priority of the global eradication programme. We assessed the immunogenicity and safety of a novel monovalent high-dose inactivated poliovirus type 2 vaccine (mIPV2HD) in infants. METHODS: This observer-blind, comparative, randomised controlled trial was done in a single centre in Panama. We enrolled healthy infants who had not received any previous vaccination against poliovirus. Infants were randomly assigned (1:1) by computer-generated randomisation sequence to receive a single dose of either mIPV2HD or standard trivalent IPV given concurrently with a third dose of bOPV at 14 weeks of age. At 18 weeks, all infants were challenged with one dose of monovalent type 2 OPV (mOPV2). Primary endpoints were seroconversion and median antibody titres to type 2 poliovirus 4 weeks after vaccination with mIPV2HD or IPV; and safety (as determined by the proportion and nature of serious adverse events and important medical events for 8 weeks after vaccination). The primary immunogenicity analyses included all participants for whom a post-vaccination blood sample was available. All randomised participants were included in the safety analyses. This trial is registered with ClinicalTrials.gov, number NCT02111135. FINDINGS: Between April 14 and May 9, 2014, 233 children were enrolled and randomly assigned to receive mIPV2HD (117 infants) or IPV (116 infants). 4 weeks after vaccination with mIPV2HD or IPV, seroconversion to poliovirus type 2 was recorded in 107 (93.0%, 95% CI 86.8-96.9) of 115 infants in the mIPV2HD group compared with 86 (74.8%, 65.8-82.4) of 115 infants in the IPV group (difference between groups 18.3%, 95% CI 5.0-31.1; p<0.0001), and median antibody titres against poliovirus type 2 were 181 (95% CI 72.0-362.0) in the mIPV2HD group and 36 (18.0-113.8) in the IPV group (difference between groups 98.8, 95% CI 60.7-136.9; p<0.0001). Serious adverse events were reported for six (5%) of 117 infants in the mIPV2HD group and seven (6%) of 116 infants in the IPV group during the 8-week period after vaccination; none were related to vaccination. No important medical events were reported. INTERPRETATION: Our findings lend support to the use of mIPV2HD as an option for stockpiling for outbreak response or primary protection in selected areas at risk for emergence of poliovirus type 2 during the next phase of the polio eradication plan. FUNDING: Bill & Melinda Gates Foundation. |
Characterization of air manganese exposure estimates for residents in two Ohio towns
Colledge MA , Julian JR , Gocheva VV , Beseler CL , Roels HA , Lobdell DT , Bowler RM . J Air Waste Manag Assoc 2015 65 (8) 948-57 This study was conducted to derive receptor-specific outdoor exposure concentrations of total suspended particulate (TSP) and respirable (dae ≤ 10 microm) air manganese (air-Mn) for East Liverpool and Marietta (Ohio) in the absence of facility emissions data, but where long-term air measurements were available. Our "site-surface area emissions method" used U.S. Environmental Protection Agency's (EPA) AERMOD (AMS/EPA Regulatory Model) dispersion model and air measurement data to estimate concentrations for residential receptor sites in the two communities. Modeled concentrations were used to create ratios between receptor points and calibrated using measured data from local air monitoring stations. Estimated outdoor air-Mn concentrations were derived for individual study subjects in both towns. The mean estimated long-term air-Mn exposure levels for total suspended particulate were 0.35 mug/m(3) (geometric mean [GM]) and 0.88 mug/m(3) (arithmetic mean [AM]) in East Liverpool (range: 0.014-6.32 mug/m(3)) and 0.17 mug/m(3) (GM) and 0.21 mug/m(3) (AM) in Marietta (range: 0.03-1.61 mug/m(3)). Modeled results compared well with averaged ambient air measurements from local air monitoring stations. Exposure to respirable Mn particulate matter (PM10; PM <10 mum) was higher in Marietta residents. IMPLICATIONS: Few available studies evaluate long-term health outcomes from inhalational manganese (Mn) exposure in residential populations, due in part to challenges in measuring individual exposures. Local long-term air measurements provide the means to calibrate models used in estimating long-term exposures. Furthermore, this combination of modeling and ambient air sampling can be used to derive receptor-specific exposure estimates even in the absence of source emissions data for use in human health outcome studies. |
Prospective study on neurotoxic effects in manganese-exposed bridge construction welders
Bowler RM , Gocheva V , Harris M , Ngo L , Abdelouahab N , Wilkinson J , Doty RL , Park R , Roels HA . Neurotoxicology 2011 32 (5) 596-605 BACKGROUND: In a group of 43 confined space welders dose-effect relationships had been identified for adverse neurological/neuropsychological functional effects in relation to manganese (Mn) in blood or air (cumulative exposure index). The welders' exposure to Mn was unprotected and with poor ventilation, lasting on average 16.5 months. A follow-up examination 3.5 years later, after cessation of confined space welding, was carried out to re-assess the status of mood, movement/neuromotor and cognitive functions, and olfaction. METHODS: In 2008, 26 welders (70% response rate) were retested using a similar methodology as at baseline (Bowler et al., 2007). A general linear model was used to estimate individual-specific endpoint differences over time. Mean age was 47 years, mean years of education 12.4, and mean total years of welding 16.9 years. Thirteen participants no longer welded. RESULTS: At follow-up, mean blood Mn concentration had decreased from 10.0 to 8.4 mcg/L (p=0.002). Those still welding had higher blood Mn than those no longer welding (9.9 mcg/L vs. 6.8 mcg/L, p=0.002). Several domains of cognitive functioning improved substantially as shown by large effect sizes. Emotional disturbance improved only slightly clinically, but complaints of depression and anxiety persisted. Motor dexterity/tactile function and graphomotor tremor improved significantly, while psychomotor speed remained unchanged. The findings of the neurological examination (UPDRS) did not change compared to baseline, whereas rigidity, dominant postural hand tremor and body sway worsened. Olfactory test scores remained depressed. CONCLUSION: After 3.5 years of cessation of confined space welding, only cognitive function improved significantly, while olfactory, extrapyramidal, and mood disturbances remained constant or were exacerbated. This suggests differential intrinsic vulnerabilities of the brain loci involved with Mn exposure. As the Mn exposure of the Bay Bridge welders frequently exceeded the Cal-OSHA TLV of 0.2 mg Mn/m(3) at baseline, a more stringent preventive measure is recommended for confined space welding. |
Epidemic cholera in a crowded urban environment, Port-au-Prince, Haiti
Dunkle SE , Mba-Jonas A , Loharikar A , Fouche B , Peck M , Ayers T , Archer WR , Beau De Rochars VM , Bender T , Moffett DB , Tappero JW , Dahourou G , Roels TH , Quick R . Emerg Infect Dis 2011 17 (11) 2143-2146 We conducted a case-control study to investigate factors associated with epidemic cholera. Water treatment and handwashing may have been protective, highlighting the need for personal hygiene for cholera prevention in contaminated urban environments. We also found a diverse diet, a possible proxy for improved nutrition, was protective against cholera. |
Knowledge, attitudes, and practices related to treatment and prevention of cholera, Haiti, 2010
Beau De Rochars VEM , Tipret J , Patrick M , Jacobson L , Barbour KE , Berendes D , Bensyl D , Frazier C , Domercant JW , Archer R , Roels T , Tappero JW , Handzel T . Emerg Infect Dis 2011 17 (11) 2158-2161 In response to the recent cholera outbreak, a public health response targeted high-risk communities, including resource-poor communities in Port-au-Prince, Haiti. A survey covering knowledge and practices indicated that hygiene messages were received and induced behavior change, specifically related to water treatment practices. Self-reported household water treatment increased from 30.3% to 73.9%. |
Considerations for oral cholera vaccine use during outbreak after earthquake in Haiti, 2010-2011
Date KA , Vicari A , Hyde TB , Mintz E , Danovaro-Holliday MC , Henry A , Tappero JW , Roels TH , Abrams J , Burkholder BT , Ruiz-Matus C , Andrus J , Dietz V . Emerg Infect Dis 2011 17 (11) 2105-2112 Oral cholera vaccines (OCVs) have been recommended in cholera-endemic settings and preemptively during outbreaks and complex emergencies. However, experience and guidelines for reactive use after an outbreak has started are limited. In 2010, after over a century without epidemic cholera, an outbreak was reported in Haiti after an earthquake. As intensive nonvaccine cholera control measures were initiated, the feasibility of OCV use was considered. We reviewed OCV characteristics and recommendations for their use and assessed global vaccine availability and capacity to implement a vaccination campaign. Real-time modeling was conducted to estimate vaccine impact. Ultimately, cholera vaccination was not implemented because of limited vaccine availability, complex logistical and operational challenges of a multidose regimen, and obstacles to conducting a campaign in a setting with population displacement and civil unrest. Use of OCVs is an option for cholera control; guidelines for their appropriate use in epidemic and emergency settings are urgently needed. |
Rapid assessment of cholera-related deaths, Artibonite Department, Haiti, 2010
Routh JA , Loharikar A , Fouche MDB , Cartwright EJ , Roy SL , Ailes E , Archer WR , Tappero JW , Roels TH , Dahourou G , Quick RE . Emerg Infect Dis 2011 17 (11) 2139-2142 We evaluated a high (6%) cholera case-fatality rate in Haiti. Of 39 community decedents, only 23% consumed oral rehydration salts at home, and 59% did not seek care, whereas 54% of 48 health facility decedents died after overnight admission. Early in the cholera epidemic, care was inadequate or nonexistent. |
Risk factors early in the 2010 cholera epidemic, Haiti
O'Connor KA , Cartwright E , Loharikar A , Routh J , Gaines J , Fouche MDB , Jean-Louis R , Ayers T , Johnson D , Tappero JW , Roels TH , Archer WR , Dahourou GA , Mintz E , Quick R , Mahon BE . Emerg Infect Dis 2011 17 (11) 2136-2138 During the early weeks of the cholera outbreak that began in Haiti in October 2010, we conducted a case-control study to identify risk factors. Drinking treated water was strongly protective against illness. Our results highlight the effectiveness of safe water in cholera control. |
Prevalence of transmitted HIV drug resistance in Botswana: Lessons learned from the HIVDR-Threshold Survey conducted among women presenting for routine antenatal care as part of the 2007 National Sentinel Survey
Bussmann H , de la Hoz Gomez F , Roels TH , Wester CW , Bodika SM , Moyo S , Taffa N , Anderson MG , Mine M , Bile EC , Yang C , Mphoyakgosi K , Lehotzky EA , Mlotshwa B , Mmelesi M , Seipone K , Makhema MJ , Marlink RG , Novitsky V , Essex M . AIDS Res Hum Retroviruses 2011 27 (4) 365-72 The emergence and spread of transmitted drug resistance (TDR) poses a major threat to the success of the rapidly expanding antiretroviral treatment (ART) programs in resource-limited countries. The World Health Organization recommends the use of the HIV Drug Resistance Threshold Survey (HIVDR-TS) as an affordable means to monitor the presence of TDR in these settings. We report our experiences and results of the 2007 HIVDR-TS in Botswana, a country with one of the longest-existing national public ART programs in Africa. The HIVDR-TS and HIV-1 incidence testing were performed in the two largest national sites as part of the 2007 antenatal Botswana Sentinel Survey. The HIVDR-TS showed no significant drug resistance mutations (TDR less than 5%) in one site. TDR prevalence, however, could not be ascertained at the second site due to low sample size. The agreement between HIVDR-TS eligibility criteria and laboratory-based methodologies (i.e., BED-CEIA and LS-EIA) in identifying recently HIV-1 infected adults was poor. Five years following the establishment of Botswana's public ART program, the prevalence of TDR remains low. The HIVDR-TS methodology has limitations for low-density populations as in Botswana, where the majority of antenatal sites are too small to recruit sufficient numbers of patients. In addition, the eligibility criteria (age <25 years and parity (first pregnancy)) of the HIVDR-TS performed poorly in identifying recent HIV-1 infections in Botswana. An alternative sampling strategy should be considered for the surveillance of HIVDR in Botswana and similar geographic settings. |
Challenge pools of hepatitis C virus genotypes 1-6 prototype strains: replication fitness and pathogenicity in chimpanzees and human liver-chimeric mouse models
Bukh J , Meuleman P , Tellier R , Engle RE , Feinstone SM , Eder G , Satterfield WC , Govindarajan S , Krawczynski K , Miller RH , Leroux-Roels G , Purcell RH . J Infect Dis 2010 201 (9) 1381-9 Chimpanzees represent the only animal model for studies of the natural history of hepatitis C virus (HCV). To generate virus stocks of important HCV variants, we infected chimpanzees with HCV strains of genotypes 1-6 and determined the infectivity titer of acute-phase plasma pools in additional animals. The courses of first- and second-passage infections were similar, with early appearance of viremia, HCV RNA titers of >10(4.7) IU/mL, and development of acute hepatitis; the chronicity rate was 56%. The challenge pools had titers of 10(3)-10(5) chimpanzee infectious doses/mL. Human liver-chimeric mice developed high-titer infections after inoculation with the challenge viruses of genotypes 1-6. Inoculation studies with different doses of the genotype 1b pool suggested that a relatively high virus dose is required to consistently infect chimeric mice. The challenge pools represent a unique resource for studies of HCV molecular virology and for studies of pathogenesis, protective immunity, and vaccine efficacy in vivo. |
Exposure-response relationship and risk assessment for cognitive deficits in early welding-induced manganism
Park RM , Bowler RM , Roels HA . J Occup Environ Med 2009 51 (10) 1125-36 OBJECTIVE: The exposure-response relationship for manganese (Mn)-induced adverse nervous system effects is not well described. Symptoms and neuropsychological deficits associated with early manganism were previously reported for welders constructing bridge piers during 2003 to 2004. A reanalysis using improved exposure, work history information, and diverse exposure metrics is presented here. METHODS: Ten neuropsychological performance measures were examined, including working memory index (WMI), verbal intelligence quotient, design fluency, Stroop color word test, Rey-Osterrieth Complex Figure, and Auditory Consonant Trigram tests. Mn blood levels and air sampling data in the form of both personal and area samples were available. The exposure metrics used were cumulative exposure to Mn, body burden assuming simple first-order kinetics for Mn elimination, and cumulative burden (effective dose). Benchmark doses were calculated. RESULTS: Burden with a half-life of about 150 days was the best predictor of blood Mn. WMI performance declined by 3.6 (normal = 100, SD = 15) for each 1.0 mg/m x mo exposure (P = 0.02, one tailed). At the group mean exposure metric (burden; half-life = 275 days), WMI performance was at the lowest 17th percentile of normal, and at the maximum observed metric, performance was at the lowest 2.5 percentiles. Four other outcomes also exhibited statistically significant associations (verbal intelligence quotient, verbal comprehension index, design fluency, Stroop color word test); no dose-rate effect was observed for three of the five outcomes. CONCLUSIONS: A risk assessment performed for the five stronger effects, choosing various percentiles of normal performance to represent impairment, identified benchmark doses for a 2-year exposure leading to 5% excess impairment prevalence in the range of 0.03 to 0.15 mg/m, or 30 to 150 mug/m, total Mn in air, levels that are far below those permitted by current occupational standards. More than one-third of workers would be impaired after working 2 years at 0.2 mg/m Mn (the current threshold limit value). |
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