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Background Tuberculosis (TB) preventive therapy (TPT) reduces the risk of TB disease in people with human immunodeficiency virus (HIV), yet uptake has been suboptimal in many countries. We assessed whether QuantiFERON Gold In-Tube (QGIT) during routine HIV care increased TB infection (TBI) testing and TPT prescriptions. Methods This parallel-arm, 1:1 cluster-randomized controlled trial compared the standard-of-care tuberculin skin test to QGIT in South Africa. We enrolled consenting, TPT-eligible adults diagnosed with HIV ≤30 days prior and used intention-to-treat analyses for the outcomes: proportion of patients with documented TBI results, proportion with documented TPT, and time from enrollment to outcomes. Findings We enrolled 2232 patients across 14 clinics from November 2014 to May 2017 (58% in intervention clinics). At 24 months of follow-up, more participants in intervention clinics had TBI results (69% vs 2%, P <.001) and TPT prescriptions (45% vs 30%, P =.13) than control clinics. Controlling for baseline covariates, intervention clinics had 60% (95% confidence interval, 51–68; P <.001) more participants with TBI results and 12% (95% confidence interval, −6 to 31; P =.18) more with TPT prescriptions. Among participants with results, those in intervention clinics received results and TPT faster (intervention: median of 6 and 29 days after enrollment vs control: 21 and 54 days, respectively). Interpretation In this setting, QGIT in routine HIV care resulted in more patients with TBI results. Clinicians also initiated more people with HIV on TPT in QGIT intervention clinics, and did so more quickly, than the control arm. Clinical Trials Registration NCT02119130. [ABSTRACT FROM AUTHOR]

The effect, initially observed with the BCG vaccine [[6]] and later with influenza vaccines, can last for several months and has been postulated to be responsible for nonspecific effects of vaccines [[7]]. A slow response to this issue increases the likelihood that this study will contribute to vaccine hesitancy and undermine confidence in vaccines, leading to outbreaks of vaccine-preventable diseases. [Extracted from the article]

Background: Schistosoma haematobium is a parasitic helminth that causes urogenital pathology. The impact of urogenital schistosomiasis during pregnancy on birth outcomes and child growth is poorly understood.Methods: Risk factors for urogenital schistosomiasis were characterized among 4437 pregnant women enrolled in a cluster-randomized community-based trial in rural Zimbabwe. Infection was defined via urine microscopy (≥1 S. haematobium egg) and urinalysis (hematuria). Associations between infection and pregnancy outcomes were assessed in case-control analyses using conditional logistic regression. The association of maternal infection with birthweight and length-for-age Z scores (LAZ) at 1 and 18 months of age were assessed using generalized estimating equations.Results: Urogenital schistosomiasis (egg positive and/or hematuria positive) was detected in 26.8% of pregnant women. Risk factors significantly associated with infection were maternal age, education, marital status, and religion; household drinking water source and latrine; study region; and season. Urogenital schistosomiasis was not significantly associated with adverse pregnancy outcomes (miscarriage, stillbirth, preterm, and small-for-gestational age), birthweight, neonatal death, or LAZ.Conclusions: Including pregnant women in antihelminthic treatment programs would benefit a large number of women in rural Zimbabwe. However, clearance of the low-intensity infections that predominate in this context is unlikely to have additive benefits for pregnancy outcomes or child growth.Clinical Trials Registration: NCT01824940. [ABSTRACT FROM AUTHOR]

Background Clinical outcomes of children who are human immunodeficiency virus (HIV)–exposed in sub-Saharan Africa remain uncertain. Methods The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial evaluated improved infant and young child feeding (IYCF) and/or improved water, sanitation, and hygiene in 2 rural Zimbabwean districts with 15% antenatal HIV prevalence and > 80% prevention of mother-to-child transmission (PMTCT) coverage. Children born between February 2013 and December 2015 had longitudinal HIV testing and anthropometry. We compared mortality and growth between children who were HIV-exposed and HIV-unexposed through 18 months. Children receiving IYCF were excluded from growth analyses. Results Fifty-one of 738 (7%) children who were HIV-exposed and 198 of 3989 (5%) children who were HIV-unexposed (CHU) died (hazard ratio, 1.41 [95% confidence interval {CI}, 1.02–1.93]). Twenty-five (3%) children who were HIV-exposed tested HIV positive, 596 (81%) were HIV-exposed uninfected (CHEU), and 117 (16%) had unknown HIV status by 18 months; overall transmission estimates were 4.3%–7.7%. Mean length-for-age z score at 18 months was 0.38 (95% CI,.24–.51) standard deviations lower among CHEU compared to CHU. Among 367 children exposed to HIV in non-IYCF arms, 147 (40%) were alive, HIV-free, and nonstunted at 18 months, compared to 1169 of 1956 (60%) CHU (absolute difference, 20% [95% CI, 15%–26%]). Conclusions In rural Zimbabwe, mortality remains 40% higher among children exposed to HIV, vertical transmission exceeds elimination targets, and half of CHEU are stunted. We propose the composite outcome of "alive, HIV free, and thriving" as the long-term goal of PMTCT programs. Clinical Trials Registration NCT01824940. [ABSTRACT FROM AUTHOR]

Background Norovirus is a leading cause of acute gastroenteritis worldwide, yet there is limited information on homotypic or heterotypic protection following natural infection to guide vaccine development. Methods A total of 6020 stools collected from 299 Peruvian children between 2010 and 2014 were tested by norovirus real-time reverse-transcription polymerase chain reaction followed by sequence-based genotyping. Cox proportional hazards models were used to derive adjusted hazard ratios (HRs) of infection among children with vs without prior exposure. Results Norovirus was detected in 1288 (21.3%) samples. GII.4 (26%), GII.6 (19%), and GI.3 (9%) viruses accounted for 54% of infections. Homotypic protection for GI.3 (HR, 0.35; P  = .015), GI.7 (HR, 0.19; P  = .022), GII.4 (HR, 0.39; P  < .001), and GII.6 (HR, 0.52; P  = .006) infections was observed. Hazard analysis showed that children with prior GII.4 infection exhibited heterotypic protection with a 48% reduction of subsequent GI.3 infection (HR, 0.52; P  = .005). Prior exposure to GI.3, GII.2, and GII.17 infections enhanced susceptibility to subsequent infections with several other norovirus genotypes. Conclusions Children up to 2 years of age infected with GII.4 noroviruses demonstrated both homotypic and heterotypic protection to reinfection with other genotypes. These data support the need for ongoing vaccine development efforts with GII.4 as the main component and caution the inclusion of genotypes that may enhance susceptibility to infections. [ABSTRACT FROM AUTHOR]

Background: The prediction of future obesity patterns is crucial for effective strategic planning. However, disproportionally changing body mass index (BMI) distributions pose particular challenges. Flexible modelling of the shape of BMI distributions may improve prediction performance.Methods: We used data from repeated national health surveys conducted in Mexico, Colombia and Peru at four or five time points between 1988 and 2014. Data from all surveys except the last survey were used to construct prediction models for three obesity indicators (median BMI, overweight/obesity prevalence and obesity prevalence) for the time of the last survey. We assessed their performance using predicted curves, absolute prediction errors and comparison of actual and predicted distributions. With one method, we modelled the shape of BMI distributions assuming BMI follows a Box-Cox Power Exponential (BCPE) distribution, whose parameters were modelled as a function of interval or nominal 5-year age groups, time and their interaction terms. In a second method, we modelled each of the obesity indicators directly as a function of the same covariates using quantile and logistic regression.Results: The BCPE model with interval age groups yielded the best prediction performance in predicting obesity prevalence. Average absolute prediction errors across all age groups were 4.3 percentage points (95% percentile interval: 1.9, 7.5), 2.5 (1.2, 6.1) and 1.7 (1.0, 9.3), with data from Mexico, Colombia and Peru, respectively. This superiority was weak or none for overweight/obesity prevalence and median BMI.Conclusion: The BCPE model performed better for prediction of the extremes of BMI distribution, possibly by incorporating its shape more precisely. [ABSTRACT FROM AUTHOR]

Background: We assessed the impact of water, sanitation, and hygiene (WASH) and infant and young child feeding (IYCF) interventions on enteric infections in the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe.Methods: We tested stool samples collected at 1, 3, 6, and 12 months of age and during diarrhea using quantitative molecular diagnostics for 29 pathogens. We estimated the effects of the WASH, IYCF, and combined WASH + IYCF interventions on individual enteropathogen prevalence and quantity, total numbers of pathogens detected, and incidence of pathogen-attributable diarrhea.Results: WASH interventions decreased the number of parasites detected (difference in number compared to non-WASH arms, -0.07 [95% confidence interval, -.14 to -.02]), but had no statistically significant effects on bacteria, viruses, or the prevalence and quantity of individual enteropathogens after accounting for multiple comparisons. IYCF interventions had no significant effects on individual or total enteropathogens. Neither intervention had significant effects on pathogen-attributable diarrhea.Conclusions: The WASH interventions implemented in SHINE (improved pit latrine, hand-washing stations, liquid soap, point-of-use water chlorination, and clean play space) did not prevent enteric infections. Transformative WASH interventions are needed that are more efficacious in interrupting fecal-oral microbial transmission in children living in highly contaminated environments. [ABSTRACT FROM AUTHOR]

Background Oral vaccines have lower efficacy in developing compared to developed countries. Poor water, sanitation, and hygiene (WASH) may contribute to reduced oral vaccine immunogenicity. Methods We conducted a cluster-randomized 2 × 2 factorial trial in rural Zimbabwe. Pregnant women and their infants were eligible if they lived in clusters randomized to (1) standard of care (52 clusters); (2) improved infant feeding (53 clusters); (3) WASH: ventilated improved pit latrine, 2 hand-washing stations, liquid soap, chlorine, infant play space, and hygiene counseling (53 clusters); or (4) feeding plus WASH (53 clusters). This substudy compared oral rotavirus vaccine (RVV) seroconversion (primary outcome), and seropositivity and geometric mean titer (GMT) (secondary outcomes), in WASH vs non-WASH infants by intention-to-treat analysis. Results We included 801 infants with documented RVV receipt and postvaccine titer measurements (329 from 84 WASH clusters; 472 from 102 non-WASH clusters); 328 infants with prevaccination titers were included in the primary outcome. Thirty-three of 109 (30.3%) infants in the WASH group seroconverted following rotavirus vaccination, compared to 43 of 219 (19.6%) in the non-WASH group (absolute difference, 10.6% [95% confidence interval {CI},.54%–20.7%]; P =.031). In the WASH vs non-WASH groups, 90 of 329 (27.4%) vs 107 of 472 (22.7%) were seropositive postvaccination (absolute difference, 4.7% [95% CI, –1.4% to 10.8%]; P =.130), and antirotavirus GMT was 18.4 (95% CI, 15.6–21.7) U/mL vs 14.9 (95% CI, 13.2–16.8) U/mL (P =.072). Conclusions Improvements in household WASH led to modest but significant increases in seroconversion to RVV in rural Zimbabwean infants. Clinical Trials Registration NCT01824940. [ABSTRACT FROM AUTHOR]

Background: Household surveys are an essential tool for vaccine coverage monitoring in developing countries, and the World Health Organization (WHO) Expanded Program on Immunization (EPI) cluster survey design has been a default choice for decades. In response to methodological limitations of the traditional EPI sampling, alternative methods have been proposed, based on modern statistical and geographical techniques. This study compared the coverage estimates and the time efficiency of the EPI sampling design and two alternative methods: the compact segment sampling and innovative grid-based geographical information system (GIS) sampling.Methods: We conducted a series of equal-sized concurrent prospective vaccine coverage surveys in Karachi, Pakistan, from January to December 2016, using traditional EPI, compact segment and grid-based GIS sampling methods.Results: No differences in vaccine coverage estimates were identified across sampling methods in the peri-urban setting; however, due to stronger clustering effects and correct incorporation of sampling weights, the compact segment [design effect (DEFF) = 2.03] and the grid-based GIS surveys (DEFF = 1.72) had higher design effects and, therefore, appeared to have lower statistical precision than the traditional EPI surveys (DEFF = 1.57). To achieve the same level of apparent precision, data collection activities in the compact segment surveys would require more than twice the implementation time needed compared with the traditional EPI surveys.Conclusions: The precision of the EPI surveys appeared higher than that of the alternative methods because, under a questionable self-weighting assumption, the estimated design effect did not account for variable sampling weights. The compact segment and grid-based GIS methods were designed to improve randomness and representativeness of sampling households. Although these alternative methods did not result in coverage estimates that differed from the EPI survey results in the peri-urban setting, they have a lower risk of selection bias and therefore may be preferred. [ABSTRACT FROM AUTHOR]

Background Tuberculosis (TB) remains the leading cause of death among human immunodeficiency virus (HIV)–infected individuals globally. Screening for TB at the point of HIV diagnosis with a high-sensitivity assay presents an opportunity to reduce mortality. Methods We performed a cluster randomized trial of TB screening among adults newly diagnosed with HIV in 12 primary health clinics in rural Thyolo, Malawi. Clinics were allocated in a 1:1 ratio to perform either point-of-care Xpert MTB/RIF assay (Xpert) or point-of-care light-emitting diode fluorescence microscopy (LED-FM) for individuals screening positive for TB symptoms. Asymptomatic participants were offered isoniazid preventive therapy in both arms. Investigators, but not clinic staff or participants, were masked to allocation. Our primary outcome was the incidence rate ratio (RR) of all-cause mortality within 12 months of HIV diagnosis. Results Prevalent TB was diagnosed in 24 of 1001 (2.4%) individuals enrolled in clinics randomized to Xpert, compared with 10 of 841 (1.2%) in clinics randomized to LED-FM. All-cause mortality was 22% lower in the Xpert arm than in the LED-FM arm (6.7 vs 8.6 per 100 person-years; RR, 0.78 [95% confidence interval {CI},.58–1.06]). A planned subgroup analysis suggested that participants with more advanced HIV (World Health Organization clinical stage 3 or 4) disease had lower mortality in clinics randomized to Xpert than to LED-FM (RR, 0.43 [95% CI,.22–.87]). Conclusions In rural Malawi, using point-of-care Xpert MTB/RIF to test symptomatic patients for TB at the time of HIV diagnosis reduced all-cause 12-month mortality among individuals with advanced HIV. Clinical Trials Registration NCT01450085. [ABSTRACT FROM AUTHOR]

Two reasons for the lack of success of programs or interventions are poor alignment of interventions with the causes of the problem targeted by the intervention, leading to poor efficacy (theory failure), and failure to implement interventions as designed (program failure). These failures are important for both public health programs and randomized trials. In the Sanitation Hygiene and Infant Nutrition Efficacy (SHINE) Trial, we utilize the program impact pathway (PIP) approach to track intervention implementation and behavior uptake. In this article, we present the SHINE PIP including definitions and measurements of key mediating domains, and discuss the implications of this approach for randomized trials. Operationally, the PIP can be used for monitoring and strengthening intervention delivery, facilitating course-correction at various stages of implementation. Analytically, the PIP can facilitate a richer understanding of the mediating and modifying determinants of intervention impact than would be possible from an intention-to-treat analysis alone. [ABSTRACT FROM AUTHOR]

Environmental enteric dysfunction (EED) is a virtually ubiquitous, but poorly defined, disorder of the small intestine among people living in conditions of poverty, which begins early in infancy and persists. EED is characterized by altered gut structure and function, leading to reduced absorptive surface area and impaired intestinal barrier function. It is hypothesized that recurrent exposure to fecal pathogens and changes in the composition of the intestinal microbiota initiate this process, which leads to a self-perpetuating cycle of pathology. We view EED as a primary gut disorder that drives chronic systemic inflammation, leading to growth hormone resistance and impaired linear growth. There is currently no accepted case definition or gold-standard biomarker of EED, making field studies challenging. The Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in Zimbabwe is evaluating the independent and combined effects of a package of infant feeding and/or water, sanitation, and hygiene interventions on stunting and anemia. SHINE therefore provides an opportunity to longitudinally evaluate EED in a well-characterized cohort of infants, using a panel of biomarkers along the hypothesized causal pathway. Our aims are to describe the evolution of EED during infancy, ascertain its contribution to stunting, and investigate the impact of the randomized interventions on the EED pathway. In this article, we describe current concepts of EED, challenges in defining the condition, and our approach to evaluating EED in the SHINE trial. [ABSTRACT FROM AUTHOR]

Background. The monovalent meningococcal A conjugate vaccine (PsA-TT, MenAfriVac) was developed for use in the “meningitis belt” of sub-Saharan Africa. Mali was 1 of 3 countries selected for early introduction. As this is a new vaccine, postlicensure surveillance is particularly important to identify and characterize possible safety issues. Methods. The national vaccination campaign was phased from September 2010 to November 2011. We conducted postlicensure safety surveillance for PsA-TT in 40 government clinics from southern Mali serving approximately 400 000 people 1–29 years of age. We conducted analyses with individual-level data and population-level data, and we calculated rates of adverse events using the conditional exact test, a modified vaccine cohort risk interval method, and a modified self-controlled case series method for each outcome of interest, including 18 prespecified adverse events and 18 syndromic categories. Results. An increased rate of clinic visits for fever within 3 days after vaccination was found using multiple methods for all age groups. Although other signals were found with some methods, complete assessment of all other prespecified outcomes and syndromic categories did not reveal that PsA-TT was consistently associated with any other health problem. Conclusions. No new safety concerns were identified in this study. These results are consistent with prelicensure data and other studies indicating that PsA-TT is safe. The approach presented could serve as a model for future active postlicensure vaccine safety monitoring associated with large-scale immunization campaigns in low-income countries. [ABSTRACT FROM AUTHOR]

Background. The duration of protection against tuberculosis provided by isoniazid preventive therapy is not known for human immunodeficiency virus (HIV)-infected individuals living in settings of medium tuberculosis incidence. Methods. We conducted an individual-level analysis of participants in a cluster-randomized, phased-implementation trial of isoniazid preventive therapy. HIV-infected patients who had positive tuberculin skin tests (TSTs) were followed until tuberculosis diagnosis, death, or administrative censoring. Nelson–Aalen cumulative hazard plots were generated and hazards were compared using the log-rank test. Cox proportional hazards models were fitted to investigate factors associated with tuberculosis diagnosis. Results. Between 2003 and 2009, 1954 patients with a positive TST were studied. Among these, 1601 (82%) initiated isoniazid. Overall tuberculosis incidence was 1.39 per 100 person-years (PY); 0.53 per 100 PY in those who initiated isoniazid and 6.52 per 100 PY for those who did not (adjusted hazard ratio [aHR], 0.17; 95% confidence interval [CI], .11–.25). Receiving antiretroviral therapy at time of a positive TST was associated with a reduced risk of tuberculosis (aHR, 0.69; 95% CI, .48–1.00). Nelson–Aalen plots of tuberculosis incidence showed a constant risk, with no acceleration in 7 years of follow-up for those initiating isoniazid preventive therapy. Conclusions. Isoniazid preventive therapy significantly reduced tuberculosis risk among HIV-infected patients with a positive TST. In a medium-prevalence setting, 6 months of isoniazid in HIV-infected patients with positive TST reduces tuberculosis risk over 7 years of follow-up, in contrast to results of studies in higher-burden settings in Africa. [ABSTRACT FROM AUTHOR]

Background. We assessed the impact of 12 years of pneumococcal conjugate vaccine (PCV7) use on pneumococcal nasopharyngeal carriage and serotype-specific invasive disease potential among Native Americans. Methods. Families were enrolled in a carriage study from 2006 to 2008; nasopharyngeal specimens and risk factor information were collected monthly for 7 visits. Pneumococcal carriage prevalence was compared with that before (1998-2000) and during (2001-2002) PCV7 introduction. We compared invasive disease incidence and carriage prevalence before and after PCV7 introduction to estimate changes in serotype-specific invasive potential. Results. We enrolled 1077 subjects from 302 households. There was an absolute reduction in carriage prevalence of 8.0% (95% confidence interval [CI], 4.5%-11.4%) in children aged <5 years and 3.1% (95% CI, 1.1%-5.1%) in adults. In children aged <5 years, vaccine-serotype carriage prevalence decreased by 22.8% (95% CI, 20.1%-25.3%), and nonvaccine serotype (NVT) increased by 15.9% (95% CI, 12.4%-19.3%). No significant change was detected in serotype-specific invasive potential after PCV7 introduction. Conclusions. Pneumococcal carriage prevalence decreased in all ages since PCV7 introduction; vaccineserotype carriage has been nearly eliminated, whereas the prevalence of NVT carriage has increased. The increase in the NVT invasive disease rate seems to be proportional to the increase in colonization prevalence. [ABSTRACT FROM AUTHOR]

Objective: The BED assay was developed to estimate the proportion of recent HIV infections in a population. We used the BED assay as a proxy for acute infection to quantify the associated risk of mother-to-child-transmission (MTCT) during pregnancy and delivery. Design A total of 3773 HIV-1 sero-positive women were tested within 96 h of delivery using the BED assay, and CD4 cell count measurements were taken. Mothers were classified according to their likelihood of having recently seroconverted.Methods: The risk of MTCT in utero and intra-partum was assessed comparing different groups defined by BED and CD4 cell count, adjusting for background factors using multinomial logistic models.Results: Compared with women with BED ≥ 0.8/CD4 ≥ 350 (typical of HIV-1 chronic patients) there was insufficient evidence to conclude that women presenting with BED < 0.8/CD4 ≥ 350 (typical of recent infections) were more likely to transmit in utero [adjusted odds ratio (aOR) = 1.37, 96% confidence interval (CI) 0.90-2.08, P = 0.14], whereas women with BED < 0.8/CD4 200-349 (possibly recently infected patients) had a 2.57 (95% CI 1.39-4.77, P-value < 0.01) odds of transmitting in utero. Women who had BED < 0.8/CD4 < 200 were most likely to transmit in utero (aOR 3.73, 95% CI 1.27-10.96, P = 0.02). BED and CD4 cell count were not predictive of intra-partum infections.Conclusions: These data provide evidence that in utero transmission of HIV might be higher among women who seroconvert during pregnancy. [ABSTRACT FROM AUTHOR]

Background: Previously, HIV epidemic models have used a double Weibull curve to represent high initial and late mortality of HIV-infected children, without distinguishing timing of infection (peri- or post-natally). With more data on timing of infection, which may be associated with disease progression, a separate representation of children infected early and late was proposed.Methods: Paediatric survival post-HIV infection without anti-retroviral treatment was calculated using pooled data from 12 studies with known timing of HIV infection. Children were grouped into perinatally or post-natally infected. Net mortality was calculated using cause-deleted life tables to give survival as if HIV was the only competing cause of death. To extend the curve beyond the available data, children surviving beyond 2.5 years post infection were assumed to have the same survival as young adults. Double Weibull curves were fitted to both extended survival curves to represent survival of children infected perinatally or through breastfeeding.Results: Those children infected perinatally had a much higher risk of dying than those infected through breastfeeding, even allowing for background mortality. The final-fitted double Weibull curves gave 75% survival at 5 months after infection for perinatally infected, and 1.1 years for post-natally infected children. An estimated 25% of the early infected children would still be alive at 10.6 years compared with 16.9 years for those infected through breastfeeding.Conclusions: The increase in available data has enabled separation of child mortality patterns by timing of infection allowing improvement and more flexibility in modelling of paediatric HIV infection and survival. [ABSTRACT FROM AUTHOR]

In Rakai, Uganda, human immunodeficiency virus (HIV)-positive men were randomized to undergo either immediate circumcision (intervention arm) or delayed circumcision (control arm). Penile swab samples were assayed for high-risk human papillomavirus (HR-HPV) by Roche HPV Linear Array at enrollment and at 24 months (intervention arm, 103 subjects; control arm, 107 subjects). Rate ratios (RRs) of HR-HPV were estimated by Poisson regression. At 24 months, HR-HPV prevalence was found in 57 (55.3%) of 103 subjects in the intervention arm and in 77 (71.7%) of 107 subjects in the control arm (RR, 0.77; 95% confidence interval [CI], 0.62-0.97). Multiple HR-HPV infections were found in 19 (22.4%) of 85 subjects in the intervention arm and in 45 (42.5%) of 106 subjects in the control arm (RR, 0.53; 95% CI, 0.33-0.83). New HR-HPV genotypes were acquired by 34 (42.0%) of 81 subjects in the intervention arm and by 53 (57.0%) 85 subjects in the control arm (RR, 0.74; 95% CI, 0.54-1.01; Pp.06). Multiple new HR-HPV genotypes were acquired by 8 (9.9%) of 81 subjects in the intervention arm and by 23 (24.7%) of 93 subjects in the control arm (RR, 0.40; 95% CI, 0.19-0.84; Pp.01). Circumcision did not affect the acquisition of single HR-HPV infections (RR, 1.00; 95% CI 0.65-1.53) or clearance of HR-HPV infections (RR, 1.09; 95% CI 0.94-1.27). Circumcision of HIV-positive men reduced the prevalence and incidence of multiple HR-HPV infections. Trial Registration. ClinicalTrials.gov identifier: NCT00124878. [ABSTRACT FROM AUTHOR]

Methods. Uncircumcised human immunodeficiency virus (HIV)-negative men aged 15-49 years were randomized to immediate circumcision (intervention arm, 441 subjects) or delayed circumcision (control arm, 399 subjects). Human papillomavirus (HPV) was detected by Roche HPV Linear Array at enrollment, and at 6, 12, and 24 months. Incident high-risk HPV (HR-HPV) was estimated in men who acquired a new HR-HPV genotype. HR-HPV clearance was determined in men with prior genotype-specific HR-HPV infections. Rate ratios (RRs) and 95% confidence intervals (CIs) of HR-HPV acquisition were estimated by Poisson multiple regression. Results. Enrollment characteristics were comparable between study groups. HR-HPV incidence was 19.7 cases per 100 person-years (PYs) in the intervention arm (70 cases per 355.8 PYs) and 29.4 cases per 100 PYs (125 cases per 424.8 PYs) in the control arm (RR, 0.67; 95% CI, 0.51-0.89; Pp.006). The incidence of multiple HRHPV infections was 6.7 cases per 100 PYs in the intervention arm and 14.8 cases per 100 PYs in the control arm (RR, 0.45; 95% CI, 0.28-0.73), but there was no significant effect on single infections (RR, 0.89; 95% CI, 0.60- 1.30). HR-HPV incidence was lower in the intervention arm for all genotypes and demographic/behavioral subgroups. The clearance of preexisting HR-HPV infections was 215.8 cases per 100 PYs (205 cases per 95 PYs) in the intervention arm and 159.1 cases per 100 PYs (255 cases per 160.25 PYs) in the control arm (adjusted RR, 1.39; 95% CI, 1.17-1.64). Conclusions. Male circumcision reduces the incidence of multiple HR-HPV infections and increases clearance of HR-HPV infections in HIV-uninfected men. Trial Registration. ClinicalTrials.gov identifier: NCT00425984. [ABSTRACT FROM AUTHOR]

Background. Before 7-valent pneumococcal conjugate vaccine (PCV7) introduction, invasive pneumococcal disease (IPD) rates among Navajo were several-fold those of the general US population. Only 50% of IPD cases in children involved PCV7 serotypes. Methods. We conducted active, population-based surveillance for IPD for the period 1995-2006. We documented case characteristics and serotyped the isolates. Results. Over 12-year period, we identified 1508 IPD cases, 447 of which occurred in children aged <5 years. Rates of IPD due to vaccine serotypes among children aged <1 year, 1 to <2 years, and 2 to <5 years decreased from 210, 263, and 51 cases per 100,000 population, respectively in 1995-1997 to 0 cases in 2004-2006 (P<.001). Among adults aged ⩾65 years, rates of IPD due to vaccine serotypes decreased 81% (95% confidence interval, -98% to -9%; P=.02). Rates of nonvaccine serotype IPD were unchanged in all age strata except for persons aged 18 to <40 years, among whom the rate decreased by 35% from 27 to 18 cases per 100,000 population (95% confidence interval, -57% to -1%; P=.03). Conclusions. Vaccine-serotype IPD has virtually been eliminated in the PCV7 era among Navajo of all ages. Overall rates of nonvaccine-serotype IPD have not increased, although increases have occurred for some individual types. Rates of all-serotype IPD among Navajo children remain 3-5-fold greater than in the general US population. [ABSTRACT FROM AUTHOR]

Background. Exclusive breast-feeding is protective against postnatal transmission of human immunodeficiency virus (HIV), compared with mixed breast-feeding. Accordingly, exclusive breast-feeding for 6 months is the World Health Organization's recommendation to HIV-infected mothers for whom exclusive replacement feeding is not acceptable, feasible, affordable, safe, or sustainable. The mechanism of exclusive breast-feeding protection is unknown but is hypothesized to be mediated through reduced mastitis. Methods. We compared breast milk and plasma specimens of exclusive breast-feeding and mixed breast-feeding HIV- positive mothers archived from the ZVITAMBO trial in which mixed breast-feeding was associated with a 2-fold increased risk of postnatal transmission at 18 months. Plasma HIV load, breast milk HIV load and sodium/potassium ratio were measured as a proxy for subclinical mastitis. Results. Mixed breast-feeding was not associated with mastitis or breast milk HIV load. Mastitis was associated with breast milk HIV load, and this effect increased with increasing maternal plasma HIV load; mastitis was associated with postnatal transmission only when maternal plasma HIV load was high (>3.7 log10 copies/mL). Initiation of breast-feeding within an hour of delivery was associated with exclusive breast-feeding (adjusted odds ratio, 1.62; 95% confidence interval, 1.02-2.58). Conclusions. Exclusive breast-feeding is associated with reduced postnatal transmission of HIV from mother to child, but this protection is not mediated by reduced mastitis or breast milk HIV load. The deleterious effect of mastitis increases as the mother's plasma HIV load increases. [ABSTRACT FROM AUTHOR]

Background. Pneumococcal conjugate vaccines are important for the prevention of serious illness and death among infants. Factors associated with pneumococcal conjugate vaccine immunogenicity have not been explored. Methods. Children <24 months of age received 2, 3, or 4 doses of 7-valent pneumococcal conjugate vaccine (PnCRM7) or control vaccine depending on age at enrollment. Serum samples were tested for serotype-specific antibodies by enzyme-linked immunosorbant assay. Multiple linear regression was used to determine predictors of immunogenicity.Results. Among 315 PnCRM7-vaccinated subjects and 295 control subjects enrolled at <7 months of age, geometric mean concentrations (GMCs) of antibodies were significantly higher after dose 3 than after dose 2 for all serotypes except type 4. The proportion of subjects with antibody concentrations ⩾5.0 mg/mL was higher for all serotypes, but the proportion with concentrations ⩾0.35 mg/mL was higher only for types 6B and 23F. Threedose and 2-dose regimens for those 7–11 and 12–23 months of age, respectively, were highly immunogenic. Increased maternal antibody concentrations were associated with reduced responses to dose 1 and 3 but not to dose 4 of PnCRM7. Conclusions. Maternal antibody is associated with a reduced infant response to PnCRM7 but does not interfere with immune memory. In infants, a third priming dose increases the antibody GMC and the proportion achieving an antibody concentration ⩾5.0 mg/mL but has little impact on the proportion achieving a concentration ⩾0.35 mg/mL. [ABSTRACT FROM AUTHOR]

Background. Low maternal serum retinol level is a risk factor for mother-to-child transmission (MTCT) of human immunodeficiency virus (HIV). Multiple-large-dose vitamin A supplementation of HIV-positive children reduces mortality. The World Health Organization recommends single-large-dose vitamin A supplementation for postpartum women in areas of prevalent vitamin A deficiency, neonatal dosing is under consideration. We investigated the effect that single-large-dose maternal/neonatal vitamin A supplementation has on MTCT, HIV-free survival, and mortality in HIV-exposed infants. Methods. A total of 14,110 mother-infant pairs were enrolled ⩽96 h after delivery, and both mother and infant, mother only, infant only, or neither received vitamin A supplementation in a randomized, placebo-controlled trial with a 2 × 2 factorial design. All but 4 mothers initiated breast-feeding. A total of 4495 infants born to HIV-positive women were included in the present analysis. Results. Neither maternal nor neonatal vitamin A supplementation significantly affected postnatal MTCT or overall mortality between baseline and 24 months. However, the timing of infant HIV infection modified the effect that supplementation had on mortality. Vitamin A supplementation had no effect in infants who were polymerase chain reaction (PCR) negative for HIV at baseline. In infants who were PCR negative at baseline and PCR positive at 6 weeks, neonatal supplementation reduced mortality by 28% (P = .01), but maternal supplementation had no effect. In infants who were PCR negative at 6 weeks, all 3 vitamin A regimens were associated with ∼2-fold higher mortality (P ⩽ .05). Conclusions. Targeted vitamin A supplementation of HIV-positive children prolongs their survival. However, postpartum maternal and neonatal vitamin A supplementation may hasten progression to death in breast-fed children who are PCR negative at 6 weeks. These findings raise concern about universal maternal or neonatal vitamin A supplementation in HIV-endemic areas. [ABSTRACT FROM AUTHOR]

In individuals who are infected with human immunodeficiency virus (HIV), distributions of quantitative HIV ribonucleic acid measurements may be highly left censored with an extra spike below the limit of detection LD of the assay. A two-component mixture model with the lower component entirely supported on [0, LD] is recommended to model the extra spike in univariate analysis better. Let LD1 and LD2 be the limits of detection for the two HIV viral load measurements. When estimating the correlation coefficient between two different measures of viral load obtained from each of a sample of patients, a bivariate Gaussian mixture model is recommended to model the extra spike on [0, LD1] and [0, LD2] better when the proportion below LD is incompatible with the left-hand tail of a bivariate Gaussian distribution. When the proportion of both variables falling below LD is very large, the parameters of the lower component may not be estimable since almost all observations from the lower component are falling below LD. A partial solution is to assume that the lower component's entire support is on [0, LD1]×[0, LD2]. Maximum likelihood is used to estimate the parameters of the lower and higher components. To evaluate whether there is a lower component, we apply a Monte Carlo approach to assess the p-value of the likelihood ratio test and two information criteria: a bootstrap-based information criterion and a cross-validation-based information criterion. We provide simulation results to evaluate the performance and compare it with two ad hoc estimators and a single-component bivariate Gaussian likelihood estimator. These methods are applied to the data from a cohort study of HIV-infected men in Rio de Janeiro, Brazil, and the data from the Women's Interagency HIV oral study. These results emphasize the need for caution when estimating correlation coefficients from data with a large proportion of non-detectable values when the proportion below LD is incompatible with the left-hand tail of a bivariate Gaussian distribution. [ABSTRACT FROM AUTHOR]

Background: Oropharyngeal carriage studies of Haemophilus influenzae type b (Hib) and the rapid drop in Hib invasive disease in countries with widespread Hib conjugate vaccine immunization programmes for infants have indicated there may be significant indirect effects (herd immunity) associated with these vaccines. Our goal was to quantify the magnitude of these effects in an American Indian population during its early years of Hib immunization.Methods: In a synthetic case-cohort study, we combined data from an efficacy trial, an immunization uptake records survey, and ongoing surveillance for Hib disease on the Navajo Nation from 1988 to 1992. Decline in the incidence of invasive Hib disease among children <2 years old was estimated via proportional hazards survival models as a function of individual immunization status and the proportion of immunized children in a community.Results: The predominant vaccine during the study period was Hib-OMPC (92% of immunizations). The effectiveness of receipt of at least one dose was 97.2%. Compared to communities with 0-20% coverage with at least one dose, residence in communities with 20-40% and 40-60% coverage was associated with risk reductions of 56.5% and 73.2%, respectively.Conclusions: The results indicate substantial indirect effects of Hib-OMPC immunization may occur even at relatively low levels of immunization coverage. Countries that implement Hib immunization programmes may receive greater benefits at the community level than those due to the direct protection conferred to the individual through vaccination. [ABSTRACT FROM AUTHOR]

The effects of not breastfeeding on mortality due to diarrhea and acute lower respiratory infection (ALRI) in children under 2 years of age were examined using data from a 1988–1991 longitudinal study of 9, 942 children in Metro Cebu, The Philippines. Cox regression methods were used to study the magnitude of the risks, possible interactions with birth weight and nutritional status, and the effect of additional confounding factors. Not breastfeeding had a greater effect on diarrheal mortality than on ALRI mortality. In the first 6 months of life, failing to initiate breastfeeding or ceasing to breastfeed resulted in an 8- to 10-fold increase in the rate of diarrheal mortality. The rate of mortality associated with both ALRI and diarrhea was increased nearly six times by not breastfeeding, but the rate of ALRI mortality alone was not increased. The data also suggested that the risk of mortality associated with not breastfeeding was greater for low birth weight infants and infants whose mothers had little formal education. After age 6 months, the protective effects of breastfeeding dropped dramatically. These findings underscore the importance of promoting breastfeeding, especially during the first 6 months of life, and of targeting high risk groups such as low birth weight babies and those of low socioeconomic status. Am J Epidemiol1996; 143: 1142–8. [ABSTRACT FROM AUTHOR]

The degree of protection conferred by natural rotavirus infection was estimated through analyses of data gathered as part of a 2-year rotavirus vaccine study of 1185 Native American infants. In 292 placebo recipients with complete serum sample sets, rotavirus IgA antibody indicative of infection before 2 months of age was associated with a 58% decrease in symptomatic infections throughout the trial. In all 391 placebo recipients, the preventive effectiveness of an initial symptomatic infection was 72% overall and 94% within 6 months following the infection. In contrast to studies conducted at other sites in the United States, serotype G3 was the predominant serotype associated with gastrointestinal episodes (80%). The effectiveness of an initial serotype G3 episode with respect to preventing subsequent serotype G3 episodes was 91%. [ABSTRACT FROM PUBLISHER]

Mortality was evaluated in 1972 children who had received measles vaccines at 6–11 months of age that were 10-fold (medium titer) or 100-fold (high titer) greater than standard titer. Mortality among boys did not differ by vaccine titer and was similar to mortality in children who received standard-titer vaccine. Girl recipients of high-titer vaccine had somewhat greater mortality than girls who received medium-titer vaccine (risk ratio = 1.71,95% confidence interval = 0.91–3.24). Increased mortality was associated with high-titer vaccine for girls but not for boys (P = .04). There was no evidence of selection bias or preferential health care by sex that might explain the differential mortality. This mortality pattern has been noted in two other populations with high background infant and childhood mortality. The biologic basis for this effect on mortality has not been determined. Data from this and other studies have resulted in discontinuation of the use of high-titer measles vaccines. [ABSTRACT FROM PUBLISHER]

Background Suboptimal breastfeeding contributes to >800,000 global child deaths annually. Optimal breastfeeding includes early initiation (EI) and exclusive breastfeeding (EBF) for the first 6 mo. Objectives We tested the hypothesis that an intervention targeting context and infant age-specific barriers to EI and EBF will achieve a higher EI and EBF prevalence than those of women participating in the concurrently conducted 2015 Zimbabwe Demographic Health Survey (Z-DHS). Methods We designed an intervention to promote EI and EBF, and implemented it within the Sanitation Hygiene Infant Nutrition Efficacy (SHINE) trial in rural Zimbabwe. Intervention modules were delivered at 4 perinatal time points by government-employed village health workers. We compared EI and EBF prevalence among SHINE women who provided outcomes at 1 mo (n  = 2442) and 3 mo (n  = 2728), with women in the 2015 Z-DHS. Results In cross-sectional analyses EI prevalence was 86.6% and 64.3% in the SHINE and Z-DHS samples, respectively; absolute difference (95% CI) = 22.4% (17.5%, 27.3%). EBF prevalence was similarly high (>80%) in both surveys during the first month of life; during 1 to <2 mo, 2 to <3 mo, 3 to <4 mo, 4 to <5 mo, and 5 to <6 mo, EBF prevalence was, respectively, 85%, 90%, 90%, 84%, and 75% in SHINE, and 71%, 65%, 35%, 26%, and 25% in Z-DHS; absolute difference (95% CI) = 50.2% (34.7%, 65.7%) at 5 to <6 mo. Cesarean delivery, mother's belief that intimate partner violence was sometimes justifiable, and having a male infant negatively modified the effects of the intervention. Conclusions The SHINE intervention achieved a high prevalence of EI and EBF. Concurrently addressing gender norms will be critical to make further progress. Formative studies to identify context- and infant age-specific barriers to EI and EBF may inform improvement of breastfeeding practices elsewhere. Important work remains to scale up this intervention beyond a research setting. SHINE was registered at www.clinicaltrials.gov as NCT01824940. [ABSTRACT FROM AUTHOR]

Background. Polio eradication efforts have been hampered by low responses to trivalent oral poliovirus vaccine (tOPV) in some developing countries. Since stomach acidity may neutralize vaccine viruses, we assessed whether administration of a buffer solution could improve the immunogenicity of tOPV.Methods. Healthy infants 4–6 weeks old in Sylhet, Bangladesh, were randomized to receive tOPV with or without a sodium bicarbonate and sodium citrate buffer at age 6, 10, and 14 weeks. Levels of serum neutralizing antibodies for poliovirus types 1, 2, and 3 were measured before and after vaccination, at 6 and 18 weeks of age, respectively.Findings. Serologic response rates following 3 doses of tOPV for buffer recipients and control infants were 95% and 88% (P = .065), respectively, for type 1 poliovirus; 95% and 97% (P = .543), respectively, for type 2 poliovirus; and 90% and 89% (P = .79), respectively, for type 3 poliovirus.Conclusions. Administration of a buffer solution prior to vaccination was not associated with statistically significant increases in the immune response to tOPV; however, a marginal 7% increase (P = .065) in serologic response to poliovirus type 1 was observed.Clinical Trials Registration. NCT01579825. [ABSTRACT FROM PUBLISHER]