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1.  Risk Factors for Mortality among HIV-exposed and HIV-unexposed Infants Admitted to a Neonatal Intensive Care Unit in Botswana 
Newborns admitted to neonatal intensive care units (NNU) in resource limited settings face high risk of mortality but the epidemiology of these deaths is poorly understood. We describe risk factors for NNU mortality in an area with high prevalence of HIV.
We performed a prospective cohort study of infants admitted to the NNU at a public referral hospital in Gaborone, Botswana. The primary outcome was neonatal death, defined as death within 28 days of a live delivery. Cox proportional hazard models were used to evaluate risk factors for mortality.
From October 2008 to April 2009, 449 neonates were admitted to the NNU. Cumulative mortality was 24.5% (110/449). Factors associated with increased risk of death included lack of enteral feeding (HR 18.8, 95% CI 10.3, 34.2), gestational age <28 weeks (HR 2.0, 95% CI 1.1, 3.8) and APGAR score <7 at 10 minutes (HR 2.5, 95% CI 1.5, 4.2). Among 348 (78%) infants who were fed, there was no difference in mortality between infants who were breastfed compared with those who were formula fed or had mixed feeding (p=0.76). There was no significant mortality difference by HIV exposure status; 35 (28%) of 128 HIV-exposed infants died compared with 55 (21%) of 272 HIV-unexposed infants (p=0.19).
This study identified low Apgar scores, extreme prematurity, and lack of enteral feeding as the most important risk factors for mortality in this NNU setting. HIV exposure and formula feeding were not significantly associated with death in neonates who were very ill.
PMCID: PMC4310460  PMID: 24372811
Botswana; neonatal intensive care units; neonatal mortality; HIV; feeding method
2.  Daily Acyclovir to Decrease Herpes Simplex Virus Type 2 (HSV-2) Transmission from HSV-2/HIV-1 Coinfected Persons: A Randomized Controlled Trial 
The Journal of Infectious Diseases  2013;208(9):1366-1374.
Background. Daily suppressive therapy with valacyclovir reduces risk of sexual transmission of herpes simplex virus type 2 (HSV-2) in HSV-2–serodiscordant heterosexual couples by 48%. Whether suppressive therapy reduces HSV-2 transmission from persons coinfected with HSV-2 and human immunodeficiency virus type 1 (HIV-1) is unknown.
Methods. Within a randomized trial of daily acyclovir 400 mg twice daily in African HIV-1 serodiscordant couples, in which the HIV-1–infected partner was HSV-2 seropositive, we identified partnerships in which HIV-1–susceptible partners were HSV-2 seronegative to estimate the effect of acyclovir on risk of HSV-2 transmission.
Results. We randomly assigned 911 HSV-2/HIV-1–serodiscordant couples to daily receipt of acyclovir or placebo. We observed 68 HSV-2 seroconversions, 40 and 28 in acyclovir and placebo groups, respectively (HSV-2 incidence, 5.1 cases per 100 person-years; hazard ratio [HR], 1.35 [95% confidence interval, .83–2.20]; P = .22). Among HSV-2–susceptible women, vaginal drying practices (adjusted HR, 44.35; P = .004) and unprotected sex (adjusted HR, 9.91; P = .002) were significant risk factors for HSV-2 acquisition; having more children was protective (adjusted HR, 0.47 per additional child; P = .012). Among HSV-2–susceptible men, only age ≤30 years was associated with increased risk of HSV-2 acquisition (P = .016).
Conclusions. Treatment of African HSV-2/HIV-1–infected persons with daily suppressive acyclovir did not decrease risk of HSV-2 transmission to susceptible partners. More-effective prevention strategies to reduce HSV-2 transmission from HIV-1–infected persons are needed.
PMCID: PMC3789565  PMID: 23901094
HSV-2; HIV-1; acyclovir; transmission; serodiscordant couples; Africa
3.  Effects of early versus delayed initiation of antiretroviral treatment on clinical outcomes of HIV-1 infection: results from the phase 3 HPTN 052 randomised controlled trial 
The Lancet. Infectious diseases  2014;14(4):281-290.
Use of antiretroviral treatment for HIV-1 infection has decreased AIDS-related morbidity and mortality and prevents sexual transmission of HIV-1. However, the best time to initiate antiretroviral treatment to reduce progression of HIV-1 infection or non-AIDS clinical events is unknown. We reported previously that early antiretroviral treatment reduced HIV-1 transmission by 96%. We aimed to compare the effects of early and delayed initiation of antiretroviral treatment on clinical outcomes.
The HPTN 052 trial is a randomised controlled trial done at 13 sites in nine countries. We enrolled HIV-1-serodiscordant couples to the study and randomly allocated them to either early or delayed antiretroviral treatment by use of permuted block randomisation, stratified by site. Random assignment was unblinded. The HIV-1-infected member of every couple initiated antiretroviral treatment either on entry into the study (early treatment group) or after a decline in CD4 count or with onset of an AIDS-related illness (delayed treatment group). Primary events were AIDS clinical events (WHO stage 4 HIV-1 disease, tuberculosis, and severe bacterial infections) and the following serious medical conditions unrelated to AIDS: serious cardiovascular or vascular disease, serious liver disease, end-stage renal disease, new-onset diabetes mellitus, and non-AIDS malignant disease. Analysis was by intention-to-treat. This trial is registered with, number NCT00074581.
1763 people with HIV-1 infection and a serodiscordant partner were enrolled in the study; 886 were assigned early antiretroviral treatment and 877 to the delayed treatment group (two individuals were excluded from this group after randomisation). Median CD4 counts at randomisation were 442 (IQR 373–522) cells per μL in patients assigned to the early treatment group and 428 (357–522) cells per μL in those allocated delayed antiretroviral treatment. In the delayed group, antiretroviral treatment was initiated at a median CD4 count of 230 (IQR 197–249) cells per μL. Primary clinical events were reported in 57 individuals assigned to early treatment initiation versus 77 people allocated to delayed antiretroviral treatment (hazard ratio 0·73, 95% CI 0·52–1·03; p=0·074). New-onset AIDS events were recorded in 40 participants assigned to early antiretroviral treatment versus 61 allocated delayed initiation (0·64, 0·43–0·96; p=0·031), tuberculosis developed in 17 versus 34 patients, respectively (0·49, 0·28–0·89, p=0·018), and primary non-AIDS events were rare (12 in the early group vs nine with delayed treatment). In total, 498 primary and secondary outcomes occurred in the early treatment group (incidence 24·9 per 100 person-years, 95% CI 22·5–27·5) versus 585 in the delayed treatment group (29·2 per 100 person-years, 26·5–32·1; p=0·025). 26 people died, 11 who were allocated to early antiretroviral treatment and 15 who were assigned to the delayed treatment group.
Early initiation of antiretroviral treatment delayed the time to AIDS events and decreased the incidence of primary and secondary outcomes. The clinical benefits recorded, combined with the striking reduction in HIV-1 transmission risk previously reported, provides strong support for earlier initiation of antiretroviral treatment.
US National Institute of Allergy and Infectious Diseases.
PMCID: PMC4144040  PMID: 24602844
4.  No Clinically Significant Drug Resistance Mutations In HIV-1 subtype C Infected Women After Discontinuation Of NRTI-Based Or PI-Based HAART For PMTCT In Botswana 
Risk of developing drug resistance after stopping antiretroviral regimens to prevent mother-to-child HIV-1 transmission (PMTCT) is unknown. Mma Bana Study randomized treatment-naïve pregnant women with CD4 ≥200 cells/mm3 to receive either abacavir/zidovudine/lamivudine (triple NRTI arm) or lopinavir/ritonavir/zidovudine/lamivudine (PI arm). Drugs were discontinued after 6 months breastfeeding. One month post-discontinuation, 29 NRTI arm samples and 25 PI arm samples were successfully genotyped. No clinically significant antiretroviral resistance mutations were detected. Eight minor resistance mutations were found among 11(20%) women (3 from NRTI arm, 8 from PI arm), occurring at similar frequencies to those reported in HIV-1 subtype C treatment naive cohorts.
PMCID: PMC3762949  PMID: 23542639
Mother-to-Child HIV transmission; Highly Active Antiretroviral Therapy; Minor drug resistance mutations; Botswana
5.  Estimating the Prevalence of Transmitted HIV Drug Resistance Using Pooled Samples 
Statistical methods in medical research  2013;10.1177/0962280212473514.
In many resource-poor countries, hiv-infected patients receive a standardized antiretroviral (art) cocktail. In these settings, population-level surveillance of drug resistance is needed to characterize the prevalence of resistance mutations and to enable art programs to select the optimal regimen for their local population. The surveillance strategy currently recommended by the World Health Organization is prohibitively expensive in some settings and may not provide a sufficiently precise rendering of the emergence of drug resistance. By using a novel assay on pooled sera samples, we decrease surveillance costs while simultaneously increasing the accuracy of drug resistance prevalence estimates for an important mutation that impacts first-line antiretroviral therapy. We present a Bayesian model for pooled-testing data that garners more information from each resistance assay conducted, compared with individual testing. We expand on previous pooling methods to account for uncertainty about the population distribution of within-subject resistance levels. In addition, our model accounts for measurement error of the resistance assay, and this added uncertainty naturally propagates through the Bayesian model to our inference on the prevalence parameter. We conduct a simulation study that informs our pool size recommendations and that shows that this model renders the prevalence parameter identifiable in instances when an existing non-model-based estimator fails.
PMCID: PMC3994180  PMID: 23376965
pooling; HIV; primary drug resistance; Bayesian modelling; measurement error
6.  HIV transmission and 24-month survival in a randomized trial of HAART to prevent MTCT during pregnancy and breastfeeding in Botswana (The Mma Bana Study) 
AIDS (London, England)  2013;27(12):1911-1920.
Highly active antiretroviral therapy (HAART) for prevention of mother-to-child HIV transmission (MTCT) may impact long-term survival of mothers and children.
Randomized clinical trial.
HIV–infected pregnant women with CD4 ≥200 cells/mm3 were randomly assigned to abacavir, zidovudine, lamivudine (Arm A) or lopinavir–ritonavir, zidovudine–lamivudine (Arm B) from week 26–34 gestation through planned weaning by 6 months postpartum. Women with baseline CD4 <200 received nevirapine–zidovudine–lamivudine indefinitely (Obs arm), as did randomized women later qualifying for treatment.
Among 560 randomized and 170 observational women enrolled, there were 14 deaths (1.9%); 1 antenatally (Obs), 3 from delivery though 6 months postpartum (1 Arm A, 2 Obs), and 10 from 6–24 months postpartum (5 Arm A, 3 Arm B, 2 Obs). Time to death or CD4 <200 was shorter in Arm A vs. B (p=0.03). Of 709 live-born children, 97% breastfed for median 5.8 months. Of 37 (5.2%) deaths by 24 months, 9 were before breastfeeding initiated (3 Arm A, 2 Arm B, 4 Obs); 6 while breastfeeding (1 Arm A, 2 Arm B, 3 Obs); and 22 after weaning (9 Arm A, 11 Arm B, 2 Obs). Only 8 children (1.1%) were HIV-infected at 24 months (6 Arm A, 1 Arm B, 1 Obs), all before 6 months.
Low MTCT was maintained through extended follow-up in all arms. Disease progression appeared slower after discontinuing protease inhibitor-based HAART, but a concerning number of maternal deaths occurred after stopping either regimen. Strategies to improve maternal and child survival in the post-intervention period are required.
PMCID: PMC3987116  PMID: 24180000
HIV; MTCT; Botswana; Africa; Antiretrovirals; Infant Survival; Maternal Health
7.  Persistently Elevated Serum Interleukin-6 Predicts Mortality Among Adults Receiving Combination Antiretroviral Therapy in Botswana: Results from a Clinical Trial 
Elevated serum levels of inflammatory biomarkers have been associated with increased mortality and morbidity among HIV-infected individuals receiving combination antiretroviral therapy (cART) in European and U.S. cohorts. Few similar data are available from sub-Saharan Africa, where most cART-treated adults reside and the prevalence of advanced immunosuppression and opportunistic infections (OIs) at cART initiation is higher. This was a retrospective nested case-control analysis of clinical trial data from the completed Adult Antiretroviral Treatment and Drug Resistance (“Tshepo”) study, 2002–2007, Gaborone, Botswana. We measured pretreatment serum levels of interleukin-6 (IL-6), high sensitivity C-reactive protein, and D-dimer in stored plasma samples from 32 deceased participants (cases) and 64 survivors (controls), matched for age, sex, baseline CD4+ cell count, and plasma HIV-1 RNA. Multivariate conditional logistic regression analyses were used to compare inflammatory biomarker levels, adjusting for pretreatment body mass index (BMI) and the presence of OIs. A total of 37 (5.7%) of 650 patients died on study, for a crude mortality rate of 20.6/1,000 person-years. Of 37 (86%) study participants who died on study 32 were included in this analysis. Causes of death (n=32) included non-AIDS-defining events (31.3%), HIV-related OIs (28.1%), cART/toxicity-related (21.9%), other infectious etiologies (15.6%), and unknown (3.1%). Median time to death was 31 weeks [interquartile range (IQR) 14–64]. Median baseline levels of all three biomarkers were higher in cases compared to matched controls. After adjusting for BMI and the presence of OIs, only baseline and most recent (near time of event) levels of IL-6 remained as significant predictors of all-cause mortality [adjusted OR (aOR)=1.25, 95% CI (1.05–1.48); p=0.012; and aOR=1.48 (1.05–2.09); p=0.027, respectively]. Serum IL-6 levels are important predictors of all-cause mortality in this adult urban sub-Saharan African cART-treated population. Future translational studies are warranted to better elucidate pathophysiology and inform the design of novel interventions to ameliorate the risk of death among these “at-risk” individuals.
PMCID: PMC3685692  PMID: 23590237
9.  HIV-1 drug mutations in children from northern Tanzania 
In resource-limited settings, it is a challenge to get quality clinical specimens due to poor infrastructure for their collection, transportation, processing and storage. Using dried blood spots (DBS) might be an alternative to plasma for HIV-1 drug resistance testing in this setting. The objectives of this study were to determine mutations associated with antiretroviral resistance among children <18 months old born to HIV-1-infected mothers enrolled in prevention of mother-to-child transmission services in northern Tanzania.
Patients and methods
Kilimanjaro Christian Medical Center (KCMC) Clinical Laboratory is the zonal centre for early infant diagnosis using DBS in northern Tanzania. DBS were collected from January 2011 to December 2012. Mothers were kept on triple therapy and single-dose nevirapine before pregnancy and during labour, respectively. Infants were given single-dose nevirapine and most of them were breastfed. Genotypic resistance was determined in those with a viral load of >400 copies/mL.
Genotypic resistance mutations were detected in 13 of 46 children (28%). HIV-1 genotypes were A1 (n = 27), C (n = 10), A/D (n = 4), D (n = 3) and CRF10_CD (n = 2). The median age was 12 weeks (IQR 6–28). The mean log10 viral load was 3.87 copies/mL (SD 0.995). All major mutations were detected in the reverse transcriptase gene and none in the protease gene region. The most frequent mutations were Y181C (n = 8) and K103N (n = 4), conferring resistance to non-nucleoside reverse transcriptase inhibitors.
One-third of infants newly diagnosed with HIV in northern Tanzania harboured major drug resistance mutations to currently used antiretroviral regimens. These mutations were detected from DBS collected from the field and stored at room temperature. Surveillance of drug resistance among this population in resource-limited settings is warranted.
PMCID: PMC4054989  PMID: 24729604
dried blood spots; antiretroviral therapy; mutations; sub-Saharan Africa; early infant diagnosis; child
10.  Plasma Viral Loads During Early HIV-1 Infection Are Similar in Subtype C– and Non-Subtype C–Infected African Seroconverters 
The Journal of Infectious Diseases  2013;207(7):1166-1170.
Recent data suggest that infection with human immunodeficiency virus type 1 (HIV-1) subtype C results in prolonged high-level viremia (>5 log10 copies/mL) during early infection. We examined the relationship between HIV-1 subtype and plasma viremia among 153 African seroconverters. Mean setpoint viral loads were similar for C and non-C subtypes: 4.36 vs 4.42 log10 copies/mL (P = .61). The proportion of subtype C–infected participants with viral loads >5 log10 copies/mL was not greater than the proportion for those with non-C infection. Our data do not support the hypothesis that higher early viral load accounts for the rapid spread of HIV-1 subtype C in southern Africa.
PMCID: PMC3583276  PMID: 23315322
HIV-1; group M subtype; plasma viral load; early infection; Africa
11.  Immune Activation Markers in Peripartum Women in Botswana: Association with Feeding Strategy and Maternal Morbidity 
PLoS ONE  2014;9(3):e89928.
Hormone levels shift the immune state in HIV-uninfected pregnant and breastfeeding women away from Th1 responses and toward regulation to permit fetal tolerance. Limited data exist on inflammation during pregnancy or postpartum in HIV-infected women, though certain inflammatory markers are associated with adverse health outcomes among HIV-infected persons.
We measured hsCRP, D-dimer, IFN-γ, IL-6, IL-10 and TNF-α at 34 weeks gestation and six months postpartum in HIV-infected women from the Botswana Mashi PMTCT trial who were randomized to breastfeeding or formula-feeding. Differences in inflammatory markers between gestation and postpartum periods, and by randomized feeding method, were estimated using generalized estimating equations, adjusting for baseline plasma HIV-1 viral load, CD4 count, calendar time, and antiretroviral treatment status. Additionally, we studied the association between marker concentrations at six months postpartum and major adverse clinical events over the following 4.5 years, using case-cohort sampling and adjusted Cox proportional hazards models.
In 86 breastfeeding and 75 formula-feeding women, hsCRP and D-dimer decreased significantly between 34 weeks gestation and six months postpartum, while IFN-γ increased. There was no significant association between inflammatory marker change and randomized feeding method after adjusting for multiple comparisons and removing outliers. In univariate analysis, TNF-α, D-dimer, and IFN-γ concentrations at six months postpartum were significant predictors of subsequent clinical events, and TNF-α remained significant in multivariate analysis (HR = 4.16, p = 0.001).
In young HIV-infected women in Botswana inflammatory marker concentrations did not differ significantly between women who breast- vs. formula-fed. However, postpartum TNF-α level was predictive of subsequent adverse clinical event.
PMCID: PMC3962339  PMID: 24657960
12.  Highly Active Antiretroviral Therapy and Adverse Birth Outcomes Among HIV-Infected Women in Botswana 
The Journal of Infectious Diseases  2012;206(11):1695-1705.
Background. It is unknown whether adverse birth outcomes are associated with maternal highly active antiretroviral therapy (HAART) in pregnancy, particularly in resource-limited settings.
Methods. We abstracted obstetrical records at 6 sites in Botswana for 24 months. Outcomes included stillbirths (SBs), preterm delivery (PTD), small for gestational age (SGA), and neonatal death (NND). Among human immunodeficiency virus (HIV)–infected women, comparisons were limited to HAART exposure status at conception, and those with similar opportunities for outcomes. Comparisons were adjusted for CD4+ lymphocyte cell count.
Results. Of 33 148 women, 32 113 (97%) were tested for HIV, of whom 9504 (30%) were HIV infected. Maternal HIV was significantly associated with SB, PTD, SGA, and NND. Compared with all other HIV-infected women, those continuing HAART from before pregnancy had higher odds of PTD (adjusted odds ratio [AOR], 1.2; 95% confidence interval [CI], 1.1, 1.4), SGA (AOR, 1.8; 95% CI, 1.6, 2.1) and SB (AOR, 1.5; 95% CI, 1.2, 1.8). Among women initiating antiretroviral therapy in pregnancy, HAART use (vs zidovudine) was associated with higher odds of PTD (AOR, 1.4; 95% CI, 1.2, 1.8), SGA (AOR, 1.5; 95% CI, 1.2, 1.9), and SB (AOR, 2.5; 95% CI, 1.6, 3.9). Low CD4+ was independently associated with SB and SGA, and maternal hypertension during pregnancy with PTD, SGA, and SB.
Conclusions. HAART receipt during pregnancy was associated with increased PTD, SGA, and SB.
PMCID: PMC3488194  PMID: 23066160
13.  Quantifying Ongoing HIV-1 Exposure in HIV-1–Serodiscordant Couples to Identify Individuals With Potential Host Resistance to HIV-1 
The Journal of Infectious Diseases  2012;206(8):1299-1308.
Background. Immunogenetic correlates of resistance to HIV-1 in HIV-1–exposed seronegative (HESN) individuals with consistently high exposure may inform HIV-1 prevention strategies. We developed a novel approach for quantifying HIV-1 exposure to identify individuals remaining HIV-1 uninfected despite persistent high exposure.
Methods. We used longitudinal predictors of HIV-1 transmission in HIV-1 serodiscordant couples to score HIV-1 exposure and define HESN clusters with persistently high, low, and decreasing risk trajectories. The model was validated in an independent cohort of serodiscordant couples. We describe a statistical tool that can be applied to other HESN cohorts to identify individuals with high exposure to HIV-1.
Results. HIV-1 exposure was best quantified by frequency of unprotected sex with, plasma HIV-1 RNA levels among, and presence of genital ulcer disease among HIV-1–infected partners and by age, pregnancy status, herpes simplex virus 2 serostatus, and male circumcision status among HESN participants. Overall, 14% of HESN individuals persistently had high HIV-1 exposure and exhibited a declining incidence of HIV-1 infection over time.
Conclusions. A minority of HESN individuals from HIV-1–discordant couples had persistent high HIV-1 exposure over time. Decreasing incidence of infection in this group suggests these individuals were selected for resistance to HIV-1 and may be most appropriate for identifying biological correlates of natural host resistance to HIV-1 infection.
PMCID: PMC3448964  PMID: 22926009
14.  Specificity of Four Laboratory Approaches for Cross-Sectional HIV Incidence Determination: Analysis of Samples from Adults with Known Nonrecent HIV Infection from Five African Countries 
AIDS Research and Human Retroviruses  2012;28(10):1177-1183.
Assays to determine cross-sectional HIV incidence misclassify some individuals with nonrecent HIV infection as recently infected, overestimating HIV incidence. We analyzed factors associated with false-recent misclassification in five African countries. Samples from 2197 adults from Botswana, Kenya, South Africa, Tanzania, and Uganda who were HIV infected >12 months were tested using the (1) BED capture enzyme immunoassay (BED), (2) avidity assay, (3) BED and avidity assays with higher assay cutoffs (BED+avidity screen), and (4) multiassay algorithm (MAA) that includes the BED+avidity screen, CD4 cell count, and HIV viral load. Logistic regression identified factors associated with misclassification. False-recent misclassification rates and 95% confidence intervals were BED alone: 7.6% (6.6, 8.8); avidity assay alone: 3.5% (2.7, 4.3); BED+avidity screen: 2.2% (1.7, 2.9); and MAA: 1.2% (0.8, 1.8). The misclassification rate for the MAA was significantly lower than the rates for the other three methods (each p<0.05). Misclassification rates were lower when the analysis was limited to subtype C-endemic countries, with the lowest rate obtained for the MAA [0.8% (0.2, 1.9)]. Factors associated with misclassification were for BED alone: country of origin, antiretroviral treatment (ART), viral load, and CD4 cell count; for avidity assay alone: country of origin; for BED+avidity screen: country of origin and ART. No factors were associated with misclassification using the MAA. In a multivariate model, these associations remained significant with one exception: the association of ART with misclassification was completely attenuated. A MAA that included CD4 cell count and viral load had lower false-recent misclassification than the BED or avidity assays (alone or in combination). Studies are underway to compare the sensitivity of these methods for detection of recent HIV infection.
PMCID: PMC3448109  PMID: 22283149
15.  Cotrimoxazole Prophylaxis and Risk of Severe Anemia or Severe Neutropenia in HAART-Exposed, HIV-Uninfected Infants 
PLoS ONE  2013;8(9):e74171.
Prophylactic cotrimoxazole is recommended for infants born to HIV-infected mothers. However, cotrimoxazole may increase the risk of severe anemia or neutropenia.
We compared the proportion of HIV-exposed uninfected (HIV-EU) infants experiencing incident severe anemia (and separately, severe neutropenia) between a prospective cohort receiving prophylactic cotrimoxazole from 1 to 6 months vs. infants from two prior trials who did not receive cotrimoxazole. Infants were from rural and urban communities in southern Botswana.
A total of 1705 HIV-EU infants were included. Among these 645 (37.8%) were fed with iron-supplemented formula from birth. Severe anemia developed in 87 (5.1%) infants, and severe neutropenia in 164 (9.6%) infants. In an analysis stratified by infant feeding method, there were no significant differences in the risk of severe anemia by prophylactic cotrimoxazole exposure–risk difference, −0.69% (95% confidence interval [CI] −2.1 to 0.76%). Findings were similar in multivariable analysis, adjusted odds ratio (aOR) 0.35 (95% CI 0.07 to 1.65). There were also no significant differences observed for severe neutropenia by cotrimoxazole exposure, risk difference 2.0% (95% CI −1.3 to 5.2%) and aOR 0.80 (95% CI 0.33 to 1.93).
Severe anemia and severe neutropenia were infrequent among HIV-exposed uninfected infants receiving cotrimoxazole from 1–6 months of age. Concerns regarding hematologic toxicity should not limit the use of prophylactic cotrimoxazole in HIV-exposed uninfected infants. Registration Numbers
NCT01086878 (, NCT00197587 (, and NCT00270296 (
PMCID: PMC3781096  PMID: 24086319
16.  Risk Factors for Symptomatic Hyperlactatemia and Lactic Acidosis Among Combination Antiretroviral Therapy-Treated Adults in Botswana: Results from a Clinical Trial 
Nucleoside analogue reverse transcriptase inhibitors are an integral component of combination antiretroviral treatment regimens. However, their ability to inhibit polymerase-γ has been associated with several mitochondrial toxicities, including potentially life-threatening lactic acidosis. A total of 650 antiretroviral-naive adults (69% female) initiated combination antiretroviral therapy (cART) and were intensively screened for toxicities including lactic acidosis as part of a 3-year clinical trial in Botswana. Patients were categorized as no lactic acidosis symptoms, minor symptoms but lactate <4.4 mmol/liter, and symptoms with lactate ≥4.4 mmol/liter [moderate to severe symptomatic hyperlactatemia (SH) or lactic acidosis (LA)]. Of 650 participants 111 (17.1%) developed symptoms and/or laboratory results suggestive of lactic acidosis and had a serum lactate drawn; 97 (87.4%) of these were female. There were 20 events, 13 having SH and 7 with LA; all 20 (100%) were female (p<0.001). Cox proportional hazard analysis limited to the 451 females revealed that having a higher baseline BMI was predictive for the development of SH/LA [aHR=1.17 per one-unit increase (1.08–1.25), p<0.0001]. Ordered logistic regression performed among all 650 patients revealed that having a lower baseline hemoglobin [aOR=1.28 per one-unit decrease (1.1–1.49), p=0.002] and being randomized to d4T/3TC-based cART [aOR=1.76 relative to ZDV/3TC (1.03–3.01), p=0.04] were predictive of the symptoms and/or the development of SH/LA. cART-treated women in sub-Saharan Africa, especially those having higher body mass indices, should receive additional monitoring for SH/LA. Women presently receiving d4T/3TC-based cART in such settings also warrant more intensive monitoring.
PMCID: PMC3399551  PMID: 22540188
17.  Immunohaematological reference values for HIV-negative healthy adults in Botswana 
Clinical laboratories in Botswana have relied entirely on the reference intervals for normal immunohaematological values provided by manufacturers' kits and textbooks.
The aim of this study was to determine the means, medians, 2.5th and 97.5th percentile reference intervals, for normal immunohaematological values in healthy adults in Botswana.
A total of 261 healthy participants comprising 126 men (48%) and 135 (52%) women were enrolled in the southern part of Botswana, and immunological and haematological laboratory parameters were measured.
The mean age was 28.8 (95% Confidence Interval [CI] 27.7–29.8) years, with a median of 27 years and a range 18–66 years. The mean haemoglobin level was significantly lower for women (12.4 g/dL; 95% CI 12.1% – 12.7%) than men (15.1 g/dL; 95% CI 14.9% – 15.3%). The women's haemoglobin reference values (9.0 g/dL – 15.0 g/dL) levels were lower than observed in predominantly White populations (12.0 g/dL – 16.0 g/dL), but comparable with regional consensus reference intervals (9.5 g/dL – 15.8 g/dL) recently defined for East and Southern Africa.
The established values provide an important tool for patient management and could influence decisions on inclusion of participants and adverse events in clinical trials conducted locally.
PMCID: PMC3682757  PMID: 23772402
18.  High Viral Load and Elevated Angiogenic Markers Associated with Increased Risk of Preeclampsia among Women Initiating Highly Active Antiretroviral Therapy (HAART) in Pregnancy in the Mma Bana Study, Botswana 
Risk factors associated with preeclampsia in HIV-infected women remain largely unknown. Systemic angiogenic imbalance contributes to preeclampsia in HIV-uninfected women, but changes in angiogenic markers after HAART initiation have not been studied.
The Mma Bana study randomized 560 HIV-infected, HAART-naive pregnant women with CD4 counts ≥ 200 cells/mm3 between 26–34 weeks gestation to lopinavir/ritonavir/zidovudine/lamivudine or abacavir/zidovudine/lamivudine. Another 170 participants with CD4 counts < 200 cells/mm3 initiated nevirapine/zidovudine/lamivudine between 18–34 weeks gestation. Characteristics of 11 women who developed preeclampsia were compared with the remaining722 Mma Bana participants who delivered, using logistic regression. Plasma samples drawn at HAART initiation and one month later from 60 women without preeclampsia and at HAART initiation for all11 preeclamptic women were assayed for placental growth factor (PlGF) and soluble FMS toll-like tyrosine kinase-1 (sFlt-1),
Pre-HAART viral load > 100,000 copies/ml was associated with preeclampsia (OR 5.8; 95% CI 1.8, 19.4; p = 0.004). Median pre-HAART PlGF level was lower and sFLT-1 was higher in women who developed preeclampsia versus those who did not (130 vs 992 pg/ml, p=0.001; 17.5 vs 9.4 pg/ml, p=0.03, respectively). In multivariate analysis, PlGF and viral load remained significantly associated with preeclampsia. No significant changes in angiogenic factors were noted after 1 month of HAART treatment among non-preeclamptic women.
Pre-HAART viral load > 100,000 copies/ml and PlGF predicted preeclampsia among women starting HAART in pregnancy. Among non-preeclamptic women, HAART treatment did not significantly alter levels of PlGF or sFlt-1 one month into treatment.
PMCID: PMC3683097  PMID: 23344545
HIV-1; viral load; pregnancy; preeclampsia; HAART
19.  Highly Active Antiretroviral Therapy versus Zidovudine for Prevention of Mother-to-Child Transmission in a Programmatic Setting, Botswana 
Few studies have compared the programmatic effectiveness of the recommended strategies of antenatal highly-active antiretroviral therapy (HAART) and zidovudine for prevention of mother-to-child transmission (MTCT). We prospectively followed infants (93% formula-fed) whose mothers who took either HAART (258 infants) or zidovudine (170 infants) during pregnancy in the Botswana national program. Overall, 10 infants (2.5%) acquired HIV— 9 infants in the zidovudine group (5.5%, 95%CI 2.6-10.2%) and 1 infant in the HAART group (0.4%, 95%CI 0.0-2.2%). Maternal HAART was associated with decreased MTCT (P=0.001) and improved HIV-free survival (P=0.040) compared with zidovudine (with or without single-dose nevirapine) in a programmatic setting.
PMCID: PMC3196679  PMID: 21792062
20.  Validation of A Point-of-Care Lactate Device For Screening At-Risk Adults Receiving Combination Antiretroviral Therapy In Botswana 
Nucleoside reverse-transcriptase inhibitors (NRTIs) are a major component of combination antiretroviral therapy (cART) worldwide but they have been associated with mitochondrial toxicities, with one of the most significant being lactic acidosis. In southern Africa, being female and overweight (BMI > 25) as well as receiving d4T and/or ddI-based cART are risk factors for the development of this potentially life-threatening complication. It is challenging in many resource-limited settings to obtain reliable serum lactate measurements while screening for the presence of lactic acidosis. Point-of-care devices, however, are now available that provide simple, accurate measurements of serum lactate levels at relatively low cost. The objective of this study was to assess the agreement of the portable (Accutrend™ handheld) lactate analyzer to the conventional laboratory system for obtaining serum lactate.
Eighty two “at-risk” cART-treated adults were evaluated, having their lactate levels tested in parallel using both modalities.
The mean (range) lactate level for the portable device was 2.28 (0.9-5.0) compared to 1.96 (0.7-5.4) using the conventional method. There was a strong correlation (p<0.05) between the portable device and the conventional means with a Pearson correlation coefficient of 0.92 [95% CI: 0.88-0.95]. The mean bias was 0.33 [95% CI: -0.39-1.04], with the portable device having slightly higher values.
The use of a portable lactate device provides an accurate and user-friendly means of screening at-risk patients for the presence of lactic acidosis in resource-limited settings with limited laboratory capacity.
PMCID: PMC3475318  PMID: 23087782
HIV/AIDS; lactic acidosis; Botswana; Point-of-care devices; Complications of combination antiretroviral therapy (cART)
21.  Increased Risk of Preterm Delivery Among HIV-Infected Women Randomized to Protease Versus Nucleoside Reverse Transcriptase Inhibitor-Based HAART During Pregnancy 
The Journal of Infectious Diseases  2011;204(4):506-514.
(See the editorial commentary by Kourtis, on pages 493–4.)
Background. Protease inhibitor (PI)-based highly active antiretroviral therapy (HAART) use in pregnancy has been associated with preterm deliveries in some observational studies.
Methods. HIV-infected, HAART-naive pregnant women with CD4+ counts ≥200 cells/mm3 were randomized between 26 and 34 weeks gestation to lopinavir/ritonavir/zidovudine/lamivudine (PI group) or abacavir/zidovudine/lamivudine (NRTI group) in a clinical trial to prevent mother-to-child HIV transmission. Risk factors for preterm delivery (<37 weeks) and differences by randomization arm were evaluated for live infants by logistic regression.
Results. Preterm delivery rates were higher among 267 women in the PI group than 263 women in the NRTI group (21.4% vs 11.8%, P = .003). PI-based HAART was the most significant risk factor for preterm delivery [odds ratio = 2.03, 95% confidence interval 1.26–3.27, P = .004]. Mean change in maternal body mass index (BMI) 1 month after HAART initiation was lower in the PI group (P < .001); however, this was not significantly associated with preterm delivery. Neither infant hospitalizations nor mortality through 6 months of life differed by maternal regimen.
Conclusions. PI-based HAART was associated with increased preterm delivery but not increased infant hospitalizations or mortality in a clinical trial setting. The association between PI use and lower increase in BMI in late pregnancy warrants further study.
PMCID: PMC3144169  PMID: 21791651
22.  Increased Risk of Severe Infant Anemia Following Exposure to Maternal HAART, Botswana 
Maternal highly-active antiretroviral therapy (HAART) reduces mother-to-child HIV transmission (MTCT), but may increase the risk for infant anemia.
The incidence of first severe anemia (Grade 3 or 4, Division of AIDS 2004 Toxicity Table) was assessed among HIV-uninfected infants in the Mashi and Mma Bana MTCT prevention trials in Botswana. Severe anemia rates were compared between 3 groups: infants exposed to maternal HAART in utero and during breastfeeding and 1 month of postnatal zidovudine (HAART-BF); infants exposed to maternal zidovudine (ZDV) in utero, 6 months of postnatal ZDV, and breastfeeding (ZDV-BF); and infants exposed to maternal ZDV in utero, 1 month of postnatal ZDV, and formula-feeding (ZDV-FF).
A total of 1719 infants were analyzed— 691 HAART-BF, 503 ZDV-BF, and 525 ZDV-FF. Severe anemia was detected in 118 infants (7.4%). By 6 months, 12.5% of HAART-BF infants experienced severe anemia, compared with 5.3% of ZDV-BF (P<0.001) and 2.5% of ZDV-FF infants (P<0.001). In adjusted analysis, HAART-BF infants were at greater risk of severe anemia than ZDV-BF or ZDV-FF infants (adjusted odds ratios 2.6 and 5.8, respectively; P < 0.001). Most anemias were asymptomatic and improved with iron/multivitamin supplementation and cessation of ZDV exposure. However, 11 infants (0.6% of all infants) required transfusion for symptomatic anemia. Microcytosis and hypochromia were common among infants with severe anemia.
Exposure to maternal HAART starting in utero was associated with severe infant anemia. Confirmation of this finding and possible strategies to mitigate hematologic toxicity warrant further study.
Trial Registration identifiers: NCT00197587 and NCT00270296.
PMCID: PMC3112252  PMID: 21266910
Mother-to-Child Transmission; Anemia; Antiretroviral Therapy; Fetal Drug Exposure; Human Immunodeficiency Virus; Infant
23.  Net survival of perinatally and postnatally HIV-infected children: a pooled analysis of individual data from sub-Saharan Africa 
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.
PMCID: PMC3140269  PMID: 21247884
HIV; survival; paediatric
24.  Statistical Interpretation of the RV144 HIV Vaccine Efficacy Trial in Thailand: A Case Study for Statistical Issues in Efficacy Trials 
The Journal of Infectious Diseases  2011;203(7):969-975.
Recently, the RV144 randomized, double-blind, efficacy trial in Thailand reported that a prime-boost human immunodeficiency virus (HIV) vaccine regimen conferred ∼30% protection against HIV acquisition. However, different analyses seemed to give conflicting results, and a heated debate ensued as scientists and the broader public struggled with their interpretation. The lack of accounting for statistical principles helped flame the debate, and we leverage these principles to provide a more scientific interpretation. We first address interpretation of frequentist results, including interpretation of P values, synthesis of results from multiple analyses (ie, intention-to-treat versus per-protocol/fully immunized), and accounting for external efficacy trials. Second, we address how Bayesian statistics, which provide clearly interpretable statements about probabilities that the vaccine efficacy takes certain values, provide more information for weighing the evidence about efficacy than do frequentist statistics alone. Third, we evaluate RV144 for completeness of end point ascertainment and integrity of blinding, necessary tasks for establishing robustly interpretable results.
PMCID: PMC3068028  PMID: 21402548
25.  Children Who Acquire HIV Infection Perinatally Are at Higher Risk of Early Death than Those Acquiring Infection through Breastmilk: A Meta-Analysis 
PLoS ONE  2012;7(2):e28510.
Assumptions about survival of HIV-infected children in Africa without antiretroviral therapy need to be updated to inform ongoing UNAIDS modelling of paediatric HIV epidemics among children. Improved estimates of infant survival by timing of HIV-infection (perinatally or postnatally) are thus needed.
Methodology/Principal Findings
A pooled analysis was conducted of individual data of all available intervention cohorts and randomized trials on prevention of HIV mother-to-child transmission in Africa. Studies were right-censored at the time of infant antiretroviral initiation. Overall mortality rate per 1000 child-years of follow-up was calculated by selected maternal and infant characteristics. The Kaplan-Meier method was used to estimate survival curves by child's HIV infection status and timing of HIV infection. Individual data from 12 studies were pooled, with 12,112 children of HIV-infected women. Mortality rates per 1,000 child-years follow-up were 39.3 and 381.6 for HIV-uninfected and infected children respectively. One year after acquisition of HIV infection, an estimated 26% postnatally and 52% perinatally infected children would have died; and 4% uninfected children by age 1 year. Mortality was independently associated with maternal death (adjusted hazard ratio 2.2, 95%CI 1.6–3.0), maternal CD4<350 cells/ml (1.4, 1.1–1.7), postnatal (3.1, 2.1–4.1) or peri-partum HIV-infection (12.4, 10.1–15.3).
These results update previous work and inform future UNAIDS modelling by providing survival estimates for HIV-infected untreated African children by timing of infection. We highlight the urgent need for the prevention of peri-partum and postnatal transmission and timely assessment of HIV infection in infants to initiate antiretroviral care and support for HIV-infected children.
PMCID: PMC3285615  PMID: 22383946

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