William J Moss

Johns Hopkins University, Baltimore, Maryland, United States

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Publications (105)600.21 Total impact

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    ABSTRACT: Malaria control interventions have been scaled-up in Zambia in conjunction with a malaria surveillance system. Although substantial progress has been achieved in reducing morbidity and mortality, national and local information demonstrated marked heterogeneity in the impact of malaria control across the country. This study reports the high burden of malaria in Nchelenge District, Luapula Province, Zambia from 2006 to 2012 after seven years of control measures. Yearly aggregated information on cases of malaria, malaria deaths, use of malaria diagnostics, and malaria control interventions from 2006 to 2012 were obtained from the Nchelenge District Health Office. Trends in the number of malaria cases, methods of diagnosis, malaria positivity rate among pregnant women, and intervention coverage were analysed using descriptive statistics. Malaria prevalence remained high, increasing from 38% in 2006 to 53% in 2012. Increasing numbers of cases of severe malaria were reported until 2010. Intense seasonal malaria transmission was observed with seasonal declines in the number of cases between April and August, although malaria transmission continued throughout the year. Clinical diagnosis without accompanying confirmation declined from 95% in 2006 to 35% in 2012. Intervention coverage with long-lasting insecticide-treated nets and indoor residual spraying increased from 2006 to 2012. Despite high coverage with vector control interventions, the burden of malaria in Nchelenge District, Zambia remained high. The high parasite prevalence could accurately reflect the true burden, perhaps in part as a consequence of population movement, or improved access to care and case reporting. Quality information at fine spatial scales will be critical for targeting effective interventions and measurement of progress.
    Malaria Journal 04/2014; 13(1):153. · 3.49 Impact Factor
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    ABSTRACT: The timing of a child's first acute lower respiratory infection (ALRI) is important, because the younger a child is when he or she experiences ALRI, the greater the risk of death. Indoor exposure to particulate matter less than or equal to 2.5 µm in diameter (PM2.5) has been associated with increased frequency of ALRI, but little is known about how it may affect the timing of a child's first ALRI. In this study, we aimed to estimate the association between a child's age at first ALRI and indoor exposure to PM2.5 in a low-income community in Dhaka, Bangladesh. We followed 257 children from birth through age 2 years to record their age at first ALRI. Between May 2009 and April 2010, we also measured indoor concentrations of PM2.5 in children's homes. We used generalized gamma distribution models to estimate the relative age at first ALRI associated with the mean number of hours in which PM2.5 concentrations exceeded 100 µg/m(3). Each hour in which PM2.5 levels exceeded 100 µg/m(3) was independently associated with a 12% decrease (95% confidence interval: 2, 21; P = 0.021) in age at first ALRI. Interventions to reduce indoor exposure to PM2.5 could increase the ages at which children experience their first ALRI in this urban community.
    American journal of epidemiology 03/2014; · 5.59 Impact Factor
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    ABSTRACT: Early infant HIV diagnosis is challenging in sub-Saharan Africa, particularly in rural areas where laboratory capacity is limited. Specimens must be transported to central laboratories for testing, leading to delays in diagnosis and initiation of antiretroviral therapy. This study was undertaken in rural Zambia to measure the turnaround time for confirmation of HIV infection and identify delays in diagnosis. Chart reviews were conducted from 2010-2012 for children undergoing early infant HIV diagnosis at Macha Hospital in Zambia. Relevant dates, receipt of drugs by mother and child for the prevention of mother-to-child transmission (PMTCT), and test results were abstracted. 403 infants provided 476 samples for early infant diagnosis. The median age at the "6-week" and "6-month" assessments was 8.1 weeks and 7.0 months, respectively. The majority of mothers (80%) and infants (67%) received PMTCT. The median time between sample collection and arrival at the central laboratory in Lusaka was 17 days (IQR: 10, 28); arrival at the central laboratory to testing was 6 days (IQR: 5, 11); testing to return of results to the clinic was 29 days (IQR: 17, 36); arrival of results at the clinic to return of results to the caregiver was 45 days (IQR: 24, 79). The total median time from sample collection to return of results to the caregiver was 92 days (IQR: 84, 145). The proportion of HIV PCR positive samples was 12%. The total median turnaround time was shorter for HIV PCR positive as compared to negative or invalid samples (85 vs. 92 days; p = 0.08). Delays in processing and communicating test results were identified, particularly in returning results from the central laboratory to the clinic and from the clinic to the caregiver. A more efficient process is needed so that caregivers can be provided test results more rapidly, potentially resulting in earlier treatment initiation and better outcomes for HIV-infected infants.
    PLoS ONE 01/2014; 9(1):e87028. · 3.53 Impact Factor
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    ABSTRACT: Travel time and distance are barriers to care for HIV-infected children in rural sub-Saharan Africa. Decentralization of care is one strategy to scale-up access to antiretroviral therapy (ART), but few programs have been evaluated. We compared outcomes for children receiving care in mobile and hospital-affiliated HIV clinics in rural Zambia.
    PLoS ONE 01/2014; 9(8):e104884. · 3.53 Impact Factor
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    ABSTRACT: Recent outbreaks of measles and polio in low-income countries illustrate that conventional methods for estimating vaccination coverage do not adequately identify susceptible children. Immune markers of protection against vaccine-preventable diseases in oral fluid (OF) or blood may generate more accurate measures of effective vaccination history, but questions remain about whether antibody surveys are feasible and informative tools for monitoring immunization program performance compared to conventional vaccination coverage indicators. This study compares six indicators of measles vaccination status, including immune markers in oral fluid and blood, from children in rural Bangladesh and evaluates the implications of using each indicator to estimate measles vaccination coverage. A cross-sectional population-based study of children ages 12-16 months in Mirzapur, Bangladesh, ascertained measles vaccination (MCV1) history from conventional indicators: maternal report, vaccination card records, 'card + history' and EPI clinic records. Oral fluid from all participants (n = 1226) and blood from a subset (n = 342) were tested for measles IgG antibodies as indicators of MCV1 history and compared to conventional MCV1 coverage indicators. Maternal report yielded the highest MCV1 coverage estimates (90.8%), followed by EPI records (88.6%), and card + history (84.2%). Seroprotection against measles by OF (57.3%) was significantly lower than other indicators, even after adjusting for incomplete seroconversion and assay performance (71.5%). Among children with blood results, 88.6% were seroprotected, which was significantly higher than coverage by card + history and OF serostatus but consistent with coverage by maternal report and EPI records. Children with vaccination cards or EPI records were more likely to have a history of receiving MCV1 than those without cards or records. Despite similar MCV1 coverage estimates across most indicators, within-child agreement was poor for all indicators. Measles IgG antibodies in OF was not a suitable immune marker for monitoring measles vaccination coverage in this setting. Because agreement between conventional MCV1 indicators was mediocre, immune marker surveillance with blood samples could be used to validate conventional MCV1 indicators and generate adjusted results that can be compared across indicators.
    BMC Public Health 12/2013; 13(1):1211. · 2.08 Impact Factor
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    ABSTRACT: Malaria control was strengthened in Zambia over the past decade. The two primary interventions for vector control are indoor residual spraying (IRS) and long-lasting insecticide-treated nets (LLINs). Using passive malaria surveillance data collected from 2006 to 2011 through the Zambian District Health Information System, the associations between increased coverage with LLINs and IRS and the burden of malaria in Zambia was evaluated. National passive malaria surveillance data from 2006 to 2011 were analysed. A district-level, random-effects model with Poisson regression was used to explore the association between malaria cases and coverage with LLINs and IRS. Malaria cases and LLINs and IRS coverage were mapped to visualize spatiotemporal variation in malaria for each year. From 2006--2011, 24.6 million LLINs were distributed and 6.4 million houses were sprayed with insecticide. Coverage with LLINs was not uniformly distributed over the study period and IRS was targeted to central and southern districts where malaria transmission was low. LLIN coverage was associated with a reduction in malaria cases, although an increase in the number of malaria cases was reported in some districts over the study period. A high burden of malaria persisted in north-eastern Zambia, whereas a reduction in the number of reported malaria cases was observed in western and southern Zambia. Enhanced and targeted interventions in north-eastern Zambia where the burden of malaria remains high, as well as efforts to sustain low malaria transmission in the south-west, will be necessary for Zambia to achieve the national goal of being malaria free by 2030.
    Malaria Journal 12/2013; 12(1):437. · 3.49 Impact Factor
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    ABSTRACT: Exposure to particulate matter (PM2.5 ) from the burning of biomass is associated with increased risk of respiratory disease. In Dhaka, Bangladesh, households that do not burn biomass often still experience high concentrations of PM2.5 but the sources remain unexplained. We characterized the diurnal variation in the concentrations of PM2.5 in 257 households and compared the risk of experiencing high PM2.5 concentrations in biomass and non-biomass users. Indoor PM2.5 concentrations were estimated every minute over 24 hours once a month from April 2009 through April 2010. We found that households that used gas or electricity experienced PM2.5 concentrations exceeding 1000 μg/m(3) for a mean of 35 minutes within a 24-hour period compared to 66 minutes in biomass burning households. In both households that used biomass and those that had no obvious source of particulate matter, the probability of PM2.5 exceeding 1000 μg/m(3) were highest during distinct morning, afternoon and evening periods. In such densely populated settings, indoor pollution in clean fuel households may be determined by biomass used by neighbors, with the highest risk of exposure occurring during cooking periods. Community interventions to reduce biomass use may reduce exposure to high concentrations of PM2.5 in both biomass and non-biomass using households. This article is protected by copyright. All rights reserved.
    Indoor Air 08/2013; · 3.30 Impact Factor
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    ABSTRACT: Background. In 2010, Zambia had a large measles outbreak providing an opportunity to measure changes in measles serostatus following highly active antiretroviral therapy (HAART), exposure to measles virus and revaccination among children infected with human immunodeficiency virus (HIV).Methods. A prospective cohort study of 169 HIV-infected Zambian children 9 to 60 months of age with a history of measles vaccination was conducted to characterize the effects of HAART and revaccination on measles IgG serostatus by enzyme immunoassay.Results. Prior to the measles outbreak, only 23% of HIV-infected children were measles IgG seropositive at HAART initiation. After adjusting for 6-month changes in baseline age and 5% changes in nadir CD4(+) T cell percentage, HAART was not associated with measles IgG seroconversion. However, 18 of 19 children seroconverted after revaccination. Eight children seroconverted during the outbreak without revaccination and were likely exposed to wild-type measles virus but none were reported to have had clinical measles.Conclusions. Immune reconstitution after HAART initiation did not restore protective levels of measles IgG antibodies but almost all children developed protective antibody levels after revaccination. Some previously vaccinated HIV-infected children had serological evidence of exposure to wild-type measles virus without a reported history of measles.
    The Journal of Infectious Diseases 08/2013; · 5.85 Impact Factor
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    ABSTRACT: Immune marker surveys may be used as substitutes or in conjunction with traditional surveys to monitor immunization program performance. This study assessed the validity and reliability of the Microimmune anti-measles virus-specific IgG ELISA with oral fluid samples (OF-ELISA) among a random sample of children ages 12-16 months in Bangladesh. Up to two oral fluid samples and one serum sample were analyzed for the presence of protective levels of anti-measles IgG antibodies. Results from the OF-ELISA were compared to the Enzygnost anti-measles IgG ELISA with serum and multivariate logistic regression models were developed to identify risk factors for false negative oral fluid results. Anti-measles IgG antibodies were measured in 330 paired oral fluid and serum samples. Immune marker prevalence of measles IgG antibodies was significantly higher in serum (88.1%, 95% CI: [84.1, 91.5]) than oral fluid (56.1% [50.2, 61.5]). Sensitivity (60.2% [54.1, 66.0]) and specificity (75.7% [58.8, 88.2]) of the OF-ELISA were lower than expected, but sensitivity significantly improved for individuals with higher anti-measles IgG in serum. False negative oral fluid results were associated with month of sample collection and variability between data collectors and assay procedures. Due to poor performance, caution should be exercised when using oral fluid samples to assess population immunity to measles virus, especially in highly vaccinated populations.
    Journal of virological methods 07/2013; · 2.13 Impact Factor
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    ABSTRACT: To better understand trends in the burden of malaria and their temporal relationship to control activities, a survey was conducted to assess reported cases of malaria and malaria control activities in Mutasa District, Zimbabwe. Data on reported malaria cases were abstracted from available records at all three district hospitals, three rural hospitals and 25 rural health clinics in Mutasa District from 2003 to 2011. Malaria control interventions were scaled up through the support of the Roll Back Malaria Partnership, the Global Fund to Fight AIDS, Tuberculosis and Malaria, and The President's Malaria Initiative. The recommended first-line treatment regimen changed from chloroquine or a combination of chloroquine plus sulphadoxine/pyrimethamine to artemisinin-based combination therapy, the latter adopted by 70%, 95% and 100% of health clinics by 2008, 2009 and 2010, respectively. Diagnostic capacity improved, with rapid diagnostic tests (RDTs) available in all health clinics by 2008. Vector control consisted of indoor residual spraying and distribution of long-lasting insecticidal nets. The number of reported malaria cases initially increased from levels in 2003 to a peak in 2008 but then declined 39% from 2008 to 2010. The proportion of suspected cases of malaria in older children and adults remained high, ranging from 75% to 80%. From 2008 to 2010, the number of RDT positive cases of malaria decreased 35% but the decrease was greater for children younger than five years of age (60%) compared to older children and adults (26%). The burden of malaria in Mutasa District decreased following the scale up of malaria control interventions. However, the persistent high number of cases in older children and adults highlights the need for strategies to identify locally effective control measures that target all age groups.
    Malaria Journal 07/2013; 12(1):223. · 3.49 Impact Factor
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    ABSTRACT: Approximately half of all children under two years of age in Bangladesh suffer from an acute lower respiratory infection (ALRI) each year. Exposure to indoor biomass smoke has been consistently associated with an increased risk of ALRI in young children. Our aim was to estimate the effect of indoor exposure to particulate matter (PM2.5 ) on the incidence of ALRI among children in a low-income, urban community in Bangladesh. We followed 257 children through two years of age to determine their frequency of ALRI and measured the PM2.5 concentrations in their sleeping space. Poisson regression was used to estimate the association between ALRI and the number of hours per day that PM2.5 concentrations exceeded 100 μg/m(3) , adjusting for known confounders. Each hour that PM2.5 concentrations exceeded 100 μg/m(3) was associated with a 7% increase in incidence of ALRI among children aged 0-11 months (adjusted incidence rate ratio (IRR) 1.07, 95% CI 1.01-1.14), but not in children 12-23 months old (adjusted IRR 1.00, 95% CI 0.92-1.09). Results from this study suggest that reducing indoor PM2.5 exposure could decrease the frequency of ALRI among infants, the children at highest risk of death from these infections.
    Indoor Air 03/2013; · 3.30 Impact Factor
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    ABSTRACT: BACKGROUND: Antiretroviral treatment (ART) options for young children co-infected with HIV and tuberculosis are limited in resource-poor settings due to limited data on the use of efavirenz (EFV). Using available pharmacokinetic data, an EFV dosing schedule was developed for young co-infected children and implemented as the standard of care at Macha Hospital in Southern Province, Zambia. Treatment outcomes inchildren younger than 3 years of age or weighing less than 10 kg receiving either EFV-based ART plus anti-tuberculous treatment or nevirapine-based (NVP) ART were compared. METHODS: Treatment outcomes were measured in a cohort of HIV-infected children seeking care at Macha Hospital in rural Zambia from 2007 to 2010. Informationon the diagnosis and treatment of tuberculosis was abstracted from medical records. RESULTS: Forty-five children treated for tuberculosis initiated an EFV-based regimen and 69 children initiated a NVP-based regimen, 7 of whom also were treated for tuberculosis. Children receiving both regimens were comparable in age, but children receiving EFV started ART with a lower CD4(+) T-cell percentage and weight-for-age z-score. Children receiving EFV experienced increases in both CD4(+) T-cell percentage and weight-for-age z-score during follow-up, such that levels were comparable to children receiving NVP after two years of ART. Cumulative survival after 12 months of ART did not differ between groups (NVP:87%;EFV:80%;p = 0.25). Eleven children experienced virologic failure during follow-up.The adjusted hazard ratio of virologic failure comparing EFV to NVP was 0.25 (95% CI:0.05,1.24) and 0.13 (95% CI:0.03,0.62) using thresholds of 5000 and 400 copies/mL, respectively.Five children receiving EFV were reported to have had convulsions after ART initiation compared to only one child receiving NVP (p = 0.04). CONCLUSIONS: Despite poorer health at ART initiation, children treated for tuberculosis and receiving EFV-based regimens showed significant improvements comparable to children receiving NVP-based regimens. EFV-based regimens should be considered for young HIV-infected children co-infected with tuberculosis in resource-limited settings.
    PLoS ONE 01/2013; 8(1):e55111. · 3.53 Impact Factor
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    ABSTRACT: Case detection and treatment are critical to malaria control and elimination as infected individuals who do not seek medical care can serve as persistent reservoirs for transmission. Household malaria surveys were conducted in two study areas within Southern Province, Zambia in 2007 and 2008. Cross-sectional surveys were conducted approximately five times throughout the year in each of the two study areas. During study visits, adults and caretakers of children were administered a questionnaire and a blood sample was obtained for a rapid diagnostic test (RDT) for malaria. These data were used to estimate the proportions of individuals with malaria potentially identified through passive case detection at health care facilities and those potentially identified through reactive case finding. Simulations were performed to extrapolate data from sampled to non-sampled households. Radii of increasing size surrounding households with an index case were examined to determine the proportion of households with an infected individual that would be identified through reactive case detection. In the 2007 high transmission setting, with a parasite prevalence of 23%, screening neighboring households within 500 meters of an index case could have identified 89% of all households with an RDT positive resident and 90% of all RDT positive individuals. In the 2008 low transmission setting, with a parasite prevalence of 8%, screening neighboring households within 500 meters of a household with an index case could have identified 77% of all households with an RDT positive resident and 76% of all RDT positive individuals. Testing and treating individuals residing within a defined radius from an index case has the potential to be an effective strategy to identify and treat a large proportion of infected individuals who do not seek medical care, although the efficiency of this strategy is likely to decrease with declining parasite prevalence.
    PLoS ONE 01/2013; 8(8):e70972. · 3.53 Impact Factor
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    ABSTRACT: BACKGROUND: Critical to sustaining progress in malaria control is comprehensive surveillance to identify outbreaks and prevent resurgence. Serologic responses to Plasmodium falciparum antigens can serve as a marker of recent transmission and serosurveillance may be feasible on a large scale. METHODS: Satellite images were used to construct a sampling frame for the random selection of households enrolled in prospective longitudinal and cross-sectional surveys in two study areas in Southern Province, Zambia, one in 2007 and the other in 2008 and 2009. Blood was collected and stored as dried spots from participating household members. A malaria rapid diagnostic test (RDT) was used to diagnose malaria. An enzyme immunoassay (EIA) was used to detect IgG antibodies to asexual stage P. falciparum whole parasite lysate using serum eluted from dried blood spots. The expected mean annual increase in optical density (OD) value for individuals with a documented prior history of recent malaria was determined using mixed models. SatScan was used to determine the spatial clustering of households with individuals with serological evidence of recent malaria, and these households were plotted on a malaria risk map. RESULTS: RDT positivity differed markedly between the study areas and years: 28% of participants for whom serologic data were available were RDT positive in the 2007 study area, compared to 8.1% and 1.4% in the 2008 and 2009 study area, respectively. Baseline antibody levels were measured in 234 participants between April and July 2007, 435 participants between February and December 2008, and 855 participants between January and December 2009. As expected, the proportion of seropositive individuals increased with age in each year. In a subset of participants followed longitudinally, RDT positivity at the prior visit was positively correlated with an increase in EIA OD values after adjusting for age in 2007 (0.261, p = 0.003) and in 2008 (0.116, p = 0.03). RDT positivity at the concurrent visit also was associated with an increase in EIA OD value in 2007 (mean increase 0.177, p = 0.002) but not in 2008 (-0.063, p =0.50). Households comprised of individuals with serologic evidence of recent malaria overlapped areas of high malaria risk for serologic data from 2009, when parasite prevalence was lowest. CONCLUSIONS: Serological surveys to whole asexual P. falciparum antigens using blood collected as dried blood spots can be used to detect temporal and spatial patterns of malaria transmission in a region of declining malaria burden, and have the potential to identify focal areas of recent transmission.
    Malaria Journal 12/2012; 11(1):438. · 3.49 Impact Factor
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    ABSTRACT: BACKGROUND:: Exclusive breastfeeding reduces the risk of respiratory illness in infants younger than 6 months of age in developing countries by approximately half. We evaluated the effect of exclusive breastfeeding on respiratory illness with fever (RIF) in Bangladeshi infants in the context of a randomized maternal influenza immunization trial. METHODS:: Infants in a maternal vaccine trial in Dhaka, Bangladesh were prospectively assessed at weekly intervals for 6 months after birth for breastfeeding practices and RIF. We estimated the risk of a RIF episode for infants who were exclusively breastfed the prior week compared with infants not exclusively breastfed the prior week using generalized estimating equations. RESULTS:: We followed a total of 331 infants from birth to 24 weeks of age. The median weeks infants were exclusively breastfed was 15 (IQR 6-21). The adjusted independent odds of respiratory illness for exclusively breastfed infants compared with non-exclusively breastfed infants was 0.59 (95% CI 0.45-0.77) for a RIF episode. After adjusting for exclusive breastfeeding, we confirmed the previous report that maternal immunization with influenza vaccine had an independent protective effect against RIF (OR 0.72, 95% CI 0.55-0.93). No significant difference in the protective effect of exclusive breastfeeding was seen by maternal influenza immunization status. CONCLUSIONS:: Exclusive breastfeeding during the first 6 months of life and maternal immunization with influenza vaccine independently and substantially reduced respiratory illness with fever in infants.
    The Pediatric Infectious Disease Journal 12/2012; · 3.57 Impact Factor
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    ABSTRACT: Indoor exposure to particulate matter (PM) increases the risk of acute lower respiratory tract infections, which are the leading cause of death in young children in Bangladesh. Few studies, however, have measured children's exposures to indoor PM over time. The World Health Organization recommends that daily indoor concentrations of PM less than 2.5μm in diameter (PM(2.5)) not exceed 25μg/m(3). This study aimed to describe the seasonal variation and determinants of concentrations of indoor PM(2.5) in a low-income community in urban Dhaka, Bangladesh. PM(2.5) was measured in homes monthly during May 2009 to April 2010. We calculated the time-weighted average, 90th percentile PM(2.5) concentrations and the daily hours PM(2.5) exceeded 100μg/m(3). Linear regression models were used to estimate the associations between fuel use, ventilation, indoor smoking, and season to each metric describing indoor PM(2.5) concentrations. Time-weighted average PM(2.5) concentrations were 190μg/m(3) (95% CI 170-210). Sixteen percent of 258 households primarily used biomass fuels for cooking and PM(2.5) concentrations in these homes had average concentrations 75μg/m(3) (95% CI 56-124) greater than other homes. PM(2.5) concentrations were also associated with burning both biomass and kerosene, indoor smoking, and ventilation, and were more than twice as high during winter than during other seasons. Young children in this community are exposed to indoor PM(2.5) concentrations 7 times greater than those recommended by World Health Organization guidelines. Interventions to reduce biomass burning could result in a daily reduction of 75μg/m(3) (40%) in time-weighted average PM(2.5) concentrations.
    Environmental Research 11/2012; · 3.24 Impact Factor
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    ABSTRACT: The prevalence of malaria has reduced significantly in some areas over the past decade. These reductions have made local elimination possible and the research agenda has shifted to this new priority. However, there are critical issues that arise when studying malaria in low transmission settings, particularly identifying asymptomatic infections, accurate detection of individuals with microparasitaemic infections, and achieving a sufficient sample size to have an adequately powered study. These challenges could adversely impact the study of malaria elimination if they remain unanswered.
    Malaria Journal 10/2012; 11(1):353. · 3.49 Impact Factor
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    ABSTRACT: To explore immunologic risk factors for death within 90 days of HAART initiation, CD4+ and CD8+ T cell subsets were measured by flow cytometry and characterized by logistic regression in 149 Zambian children between 9 months and 10 years of age enrolled in a prospective, observational study of the impact of HAART on measles immunity. Of 21 children who died during follow-up, 17 (81%) had known dates of death and 16 (76%) died within 90 days of initiating HAART. Young age and low weight-for-age z-score were associated with increased risks of mortality within 90 days of starting HAART, whereas CD4+ T cell percentage was not associated with mortality. After adjusting for these factors, each 10% increase in CD8+ effector T cells increased the odds of overall mortality (OR = 1.43 [95% CI: 1.08, 1.90]) and was marginally associated with early mortality (OR = 1.29 [95% CI: 0.97, 1.72]). Conversely, each 10% increase in CD4+ central memory T cells decreased the odds of overall (OR = 0.06 [95% CI: 0.01, 0.59]) and early mortality (OR = 0.09 [95% CI: 0.01, 0.97]). Logistic regression prediction models demonstrated areas under the receiver-operator characteristic curves of ≥85% for early and overall mortality, with bootstrapped sensitivities of 82-85% upon validation, supporting the predictive accuracy of the models. CD4+ and CD8+ T cell subsets may be more accurate predictors of early mortality than CD4+ T cell percentages and could be used to identify children who would benefit from more frequent clinical monitoring after initiating HAART.
    AIDS research and human retroviruses 10/2012; · 2.18 Impact Factor
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    ABSTRACT: BACKGROUND: Neonatal deaths account for over 40% of all deaths in children younger than five years of age and neonatal mortality rates are highest in areas affected by humanitarian emergencies. Of the ten countries with the highest neonatal mortality rates globally, six are currently or recently affected by a humanitarian emergency. Yet, little is known about newborn care in crisis settings. Understanding current policies and practices for the care of newborns used by humanitarian aid organizations will inform efforts to improve care in these challenging settings. METHODS: Between August 18 and September 25, 2009, 56 respondents that work in humanitarian emergencies completed a web-based survey either in English or French. A snow ball sampling technique was used to identify organizations that provide health services during humanitarian emergencies to gather information on current practices for maternal and newborn care in these settings. Information was collected about continuum-of-care services for maternal, newborn and child health, referral services, training and capacity development, health information systems, policies and guidelines, and organizational priorities. Data were entered into MS Excel and frequencies and percentages were calculated. RESULTS: The majority of responding organizations reported implementing components of neonatal and maternal health interventions. However, multiple barriers exist in providing comprehensive care, including: funding shortages (63.3%), gaps in training (51.0%) and staff shortages and turnover (44.9%). CONCLUSIONS: Neonatal care is provided by most of the responding humanitarian organizations; however, the quality, breadth and consistency of this care are limited.
    Conflict and Health 07/2012; 6(1):2.

Publication Stats

2k Citations
600.21 Total Impact Points

Institutions

  • 1999–2014
    • Johns Hopkins University
      • • Department of Epidemiology
      • • Department of Pediatrics
      • • Department of Molecular Microbiology and Immunology
      Baltimore, Maryland, United States
  • 2013
    • Erasmus Universiteit Rotterdam
      Rotterdam, South Holland, Netherlands
  • 2002–2012
    • Johns Hopkins Bloomberg School of Public Health
      • • Department of Epidemiology
      • • W. Harry Feinstone Department of Molecular Microbiology and Immunology
      Baltimore, Maryland, United States
  • 2009
    • Malaria Institute at Macha
      Choma, Southern, Zambia
  • 2003–2009
    • Johns Hopkins Medicine
      • • Department of Epidemiology
      • • Department of International Health
      Baltimore, MD, United States
  • 2007
    • London School of Hygiene and Tropical Medicine
      Londinium, England, United Kingdom
  • 2005
    • University of KwaZulu-Natal
      Port Natal, KwaZulu-Natal, South Africa
  • 2002–2004
    • University of Lusaka
      Lusaka, Lusaka, Zambia