HIV impact on mother and child mortality in rural Tanzania

Training and capacity building in medical statistics in Sub-Saharan Africa: Impact of the London School of Hygiene & Tropical Medicine MSc in Medical Statistics, 1969 to 2021

Since its inception in 1969, the MSc in medical statistics program has placed a high priority on training students from Africa. In this article, we review how the program has shaped, and in turn been shaped by, two substantial capacity building initiatives: (a) a fellowship program, funded by the UK Medical Research Council, and run through the International Statistical Epidemiology Group at the LSHTM, and (b) the Sub-Saharan capacity building in Biostatistics (SSACAB) initiative, administered through the Developing Excellence in Leadership, Training and Science in Africa (DELTAS) program of the African Academy of Sciences. We reflect on the impact of both initiatives, and the implications for future work in this area.

Linking the timing of a mother's and child's death: Comparative evidence from two rural South African population-based surveillance studies, 2000-2015

BACKGROUND

The effect of the period before a mother's death on child survival has been assessed in only a few studies. We conducted a comparative investigation of the effect of the timing of a mother's death on child survival up to age five years in rural South Africa.

METHODS

We used discrete time survival analysis on data from two HIV-endemic population surveillance sites (2000-2015) to estimate a child's risk of dying before and after their mother's death. We tested if this relationship varied between sites and by availability of antiretroviral therapy (ART). We assessed if related adults in the household altered the effect of a mother's death on child survival.

FINDINGS

3,618 children died from 2000-2015. The probability of a child dying began to increase in the 7-11 months prior to the mother's death and increased markedly in the 3 months before (2000-2003 relative risk = 22.2, 95% CI = 14.2-34.6) and 3 months following her death (2000-2003 RR = 20.1; CI = 10.3-39.4). This increased risk pattern was evident at both sites. The pattern attenuated with ART availability but remained even with availability at both sites. The father and maternal grandmother in the household lowered children's mortality risk independent of the association between timing of mother and child mortality.

CONCLUSIONS

The persistence of elevated mortality risk both before and after the mother's death for children of different ages suggests that absence of maternal care and abrupt breastfeeding cessation might be crucial risk factors. Formative research is needed to understand the circumstances for children when a mother is very ill or dies, and behavioral and other risk factors that increase both the mother and child's risk of dying. Identifying families when a mother is very ill and implementing training and support strategies for other members of the household are urgently needed to reduce preventable child mortality.

Risk of childhood mortality associated with death of a mother in low-and-middle-income countries: a systematic review and meta-analysis

Background

Death of a mother at an early age of the child may result in an increased risk of childhood mortality, especially in low-and-middle-income countries. This study aims to synthesize estimates of the association between a mother’s death and the risk of childhood mortality at different age ranges from birth to 18 years in these settings.

Methods

Various MEDLINE databases, EMBASE, and Global Health databases were searched for population-based cohort and case-control studies published from 1980 to 2017. Studies were included if they reported the risk of childhood mortality for children whose mother had died relative to those whose mothers were alive. Random-effects meta-analyses were used to pool effect estimates, stratified by various exposures (child’s age when mother died, time since mother’s death) and outcomes (child’s age at risk of child death).

Results

A total of 62 stratified risk estimates were extracted from 12 original studies. Childhood mortality was associated with child’s age at time of death of a mother and time since a mother’s death. For children whose mother died when they were ≤ 42 days, the relative risk (RR) of dying within the first 1–6 months of the child’s life was 35.5(95%CI:9.7–130.5, p [het] = 0.05) compared to children whose mother did not die; by 6–12 months this risk dropped to 2.8(95%CI:0.7–10.7). For children whose mother died when they were ≤ 1 year, the subsequent RR of dying in that year was 15.9(95%CI:2.2–116.1,p [het] = 0.02), compared to children whose mother lived. For children whose mother died when they were ≤ 5 years of age, the RR of dying before aged 12 was 4.1(95%CI:3.0–5.7),p [het] = 0.83. Mortality was also elevated in specific analysis  among children whose mother died when child was older than 42 days. Overall, for children whose mother died < 6 and 6+ months ago, RRs of dying before reaching adulthood (≤18 years) were 4.7(95%CI:2.6–8.7,p [het] = 0.2) and 2.1(95%CI:1.3–3.4,p [het] = 0.7), respectively, compared to children whose mother lived.

Conclusions

There is evidence of an association between the death of a mother and childhood mortality in lower resource settings. These findings emphasize the critical importance of women in family outcomes and the importance of health care for women during the intrapartum and postpartum periods and throughout their child rearing years.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7316-x) contains supplementary material, which is available to authorized users.

Willingness to pay for hypothetical malaria vaccines in rural Burkina Faso

Aims: This study aims to set priorities for anti-disease malaria vaccines by determining community preference in a hyperendemic area. Methods: A bidding game technique was used to elucidate willingness to pay in rural Burkina Faso and 2,326 adults were interviewed. Results: It is shown that there are significant differences between community preference for an anti-disease vaccine aimed at reducing pathology in pregnant women, and for a vaccine directed against childhood malaria. While the target population was willing to pay CFAfr 2101 for a vaccine against maternal malaria, its members were prepared to pay only CFAfr 1433 for a vaccine against childhood malaria. Conclusions: Whilst it is increasingly likely that anti-disease malaria vaccines will become available in the foreseeable future, lessons from the past suggest that a lack of acceptance and support from the intended recipients may lead to less than optimal compliance, and hence efficacy. For the planning of vaccine development and application strategies, it is therefore highly important to take community views into account. Here it is argued that such information could help researchers and funding agencies to set priorities for future vaccine research.

Under-five mortality and maternal HIV status in Tanzania: analysis of trends between 2003 and 2012 using AIDS Indicator Survey data

Background

Mortality among children under five remains a significant health challenge across sub-Saharan Africa. HIV/AIDS is one of the leading contributors to the relatively slow decline in under-five mortality in this region. In Tanzania, HIV prevalence among under-five children is high and 90% of all infections are due to mother-to-child transmission.

Objectives

The study aimed to examine the association between maternal HIV-positive status and under-five mortality in Tanzania. It also aimed to estimate the proportions and trends of under-five mortality attributable to maternal HIV/AIDS in Tanzania between 2003 and 2012.

Design

Binomial logistic regression was used to analyze cross-sectional survey data from the Tanzania AIDS Indicator Surveys to examine the association between maternal HIV positivity and under-five mortality between 2003 and 2012.

Results

After controlling for confounders, the adjusted odds ratios were 1.5 (95% CI 1.1–1.9) in 2003–2004, 4.6 (95% CI 2.7–7.8) in 2007–2008, and 2.4 (95% CI 1.2–4.6) in 2011–2012. The maternal HIV-attributable mortality risk percent of under-five children was 3.7 percent in 2003–2004, 11.3 percent in 2007–2008 and 5.6% in 2011–2012.

Conclusion

Maternal HIV positivity is associated with under-five mortality in Tanzania, making maternal HIV serostatus a relevant determinant of whether a child will survive up to five years of age or not. The impact of maternal HIV/AIDS attributable mortality risk has a significant contribution to the overall under-five mortality in Tanzania. The continued monitoring of HIV and mortality trends is important for policy development and design of interventions.

Health & Demographic Surveillance System Profile: The Magu Health and Demographic Surveillance System (Magu HDSS)

The Magu Health and Demographic Surveillance System (Magu HDSS) is part of Kisesa OpenCohort HIV Study located in a rural area of North-Western Tanzania. Since its establishment in 1994, information on pregnancies, births, marriages, migrations and deaths have been monitored and updated between one and three times a year by trained fieldworkers. Other research activities implemented in the cohort include: sero surveys which have been conducted every 2–3 years to collect socioeconomic data, HIV sero status and health knowledge attitude and behaviour in adults aged 15 years or more living in the area; verbal autopsy (VA) interviews conducted to establish cause of death in all deaths encountered in the area; Llnking data collected at health facilities to community-based data; monitoring voluntary counselling and testing (VCT); and assessing uptake of antiretroviral treatment (ART). In addition, within the community, qualitative studies have been conducted to address issues linked to HIV stigma, the perception of ART access and adherence.

In 2014, the population was over 35 000 individuals. Magu HDSS has contributed to Tanzanian estimates of fertility and mortality, and is a member of the INDEPTH network. Demographic data for Magu HDSS are available via the INDEPTH Network’s Sharing and Accessing Repository (iSHARE) and applications to access HDSS data for collaborative analysis are encouraged.

Increased risk for and mortality from invasive pneumococcal disease in HIV-exposed but uninfected infants aged <1 year in South Africa, 2009-2013

BACKGROUND

High antenatal human immunodeficiency virus (HIV) seroprevalence rates (∼ 30%) with low perinatal HIV transmission rates (2.5%), due to HIV prevention of mother-to-child transmission program improvements in South Africa, has resulted in increasing numbers of HIV-exposed but uninfected (HEU) children. We aimed to describe the epidemiology of invasive pneumococcal disease (IPD) in HEU infants.

METHODS

We conducted a cross-sectional study of infants aged <1 year with IPD enrolled in a national, laboratory-based surveillance program for incidence estimations. Incidence was reported for 2 time points, 2009 and 2013. At enhanced sites we collected additional data including HIV status and in-hospital outcome.

RESULTS

We identified 2099 IPD cases in infants from 2009 to 2013 from all sites. In infants from enhanced sites (n = 1015), 92% had known HIV exposure status and 86% had known outcomes. IPD incidence was highest in HIV-infected infants, ranging from 272 to 654 per 100,000 population between time points (2013 and 2009), followed by HEU (33-88 per 100,000) and HIV-unexposed and uninfected (HUU) infants (18-28 per 100,000). The case-fatality rate in HEU infants (29% [74/253]) was intermediate between HUU (25% [94/377]) and HIV-infected infants (34% [81/242]). When restricted to infants <6 months of age, HEU infants (37% [59/175]) were at significantly higher risk of dying than HUU infants (32% [51/228]; adjusted relative risk ratio, 1.76 [95% confidence interval, 1.09-2.85]).

DISCUSSION

HEU infants are at increased risk of IPD and mortality from IPD compared with HUU children, especially as young infants. HEU infants, whose numbers will likely continue to increase, should be prioritized for interventions such as pneumococcal vaccination along with HIV-infected infants and children.

Increased morbidity in early childhood among HIV-exposed uninfected children in Uganda is associated with breastfeeding duration

Human immunodeficiency virus (HIV)-exposed uninfected children (HEU) have an increased risk of morbidity and mortality compared with HIV-unexposed uninfected children (HUU); however, prior studies have not fully accounted for the role of both breastfeeding and age on this association. In this cohort of HEU and HUU in Uganda, non-breastfeeding HEU, from 6-11 months compared with non-breastfeeding HUU had a higher risk of hospitalizations [relative risk (RR): 10.1, 95% confidence interval (CI): 3.70-27.6], severe febrile illness (RR: 3.84, 95% CI: 2.06-7.17), severe diarrhea (RR: 6.37, 95% CI: 2.32-17.4) and severe malnutrition (RR: 18.4, 95% CI: 4.68-72.0). There were no differences between morbidity outcomes between breastfeeding HEU and HUU children, aged 6-11 months. In the 12-24 month age group, the only difference in morbidity outcomes among non-breast feeding children was an increased risk of severe malnutrition for HEU. These data suggest that the increased risk of morbidity among HEU aged 6-11 years is partially explained by early cessation of breastfeeding.

Efficacy and safety of three regimens for the prevention of malaria in young HIV-exposed Ugandan children: a randomized controlled trial

OBJECTIVE

Trimethoprim-sulfamethoxazole prophylaxis is recommended for HIV-exposed infants until breastfeeding ends and HIV infection has been excluded. Extending prophylaxis with a focus on preventing malaria may be beneficial in high transmission areas. We investigated three regimens for the prevention of malaria in young HIV-exposed children.

DESIGN

An open-label, randomized controlled trial.

SETTING

Tororo, Uganda, a rural area with intense, year-round, malaria transmission.

PARTICIPANTS

Two hundred infants aged 4-5 months enrolled and 186 randomized after cessation of breastfeeding and confirmed to be HIV uninfected (median 10 months of age).

INTERVENTION

No chemoprevention, monthly sulfadoxine-pyrimethamine, daily trimethoprim-sulfamethoxazole or monthly dihydroartemisinin-piperaquine given from randomization to 24 months of age.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of malaria during the intervention period. Secondary outcomes included the incidence of hospitalization, diarrhoeal illness, or respiratory tract infection; prevalence of anaemia and asymptomatic parasitemia; measures of safety; and incidence of malaria over 1 year after the intervention was stopped.

RESULTS

During the intervention, the incidence of malaria in the no chemoprevention group was 6.28 episodes per person-year at risk. Protective efficacy was 69% [95% confidence interval (95% CI) 53-80, P < 0.001] for dihydroartemisinin-piperaquine, 49% (95% CI 23-66, P = 0.001) for trimethoprim-sulfamethoxazole and 9% for sulfadoxine-pyrimethamine (95% CI -35 to 38, P = 0.65). There were no significant differences in any secondary outcomes, with the exception of a lower prevalence of asymptomatic parasitemia in the dihydroartemisinin-piperaquine arm.

CONCLUSION

Monthly chemoprevention with dihydroartemisinin-piperaquine was well tolerated and associated with a significant reduction in malaria in young HIV-exposed children.

Eliminating mother-to-child HIV transmission will require major improvements in maternal and child health services

Although some low- and middle-income countries have made progress toward eliminating mother-to-child transmission of HIV, others lack health systems that can deliver accessible and reliable care. We modeled how access to maternal and child health services and the effective delivery of interventions would affect efforts to eliminate HIV transmission during pregnancy and after childbirth in low- and middle-income countries. In countries with high HIV rates, our model predicts transmission rates of 19.7 percent at current levels of access and efficiency of maternal and child health and HIV treatment. Even if current treatment programs were carried out at or near perfect levels, we predict that significant residual mother-to-child transmission (7.9 percent) would remain. The model suggests that under current conditions, poor access to routine health services contributes three times more to overall mother-to-child HIV transmission than do current suboptimal levels of efficiency of anti-HIV-transmission interventions. We conclude that current efforts to optimize programs to prevent mother-to-child HIV transmission will not, on their own, eliminate HIV in newborns. Access to maternal and child health services will need to be dramatically improved, as will prevention measures, such as identifying and treating HIV before pregnancy.

Projecting the clinical benefits and risks of using efavirenz-containing antiretroviral therapy regimens in women of childbearing age

OBJECTIVES

To project the outcomes of using either efavirenz or nevirapine as part of initial antiretroviral therapy (ART) in women of childbearing age in Côte d'Ivoire.

METHODS

We used an HIV computer simulation model to project both the mother's survival and the birth defects at 10 years for a cohort of women who started ART with either efavirenz or nevirapine. The primary outcome was the ratio at 10 years of the difference in the number of women alive to the difference in the cumulative number of birth defects in women who started ART with efavirenz compared with nevirapine. In the base case analysis, the birth defect rate was 2.9% on efavirenz and 2.7% on nevirapine. In sensitivity analyses, we varied all inputs across confidence intervals reported in the literature.

RESULTS

In the base case analysis, for a cohort of 100 000 women, the additional number of women alive initiating ART with efavirenz at 10 years was 15 times the additional number of birth defects (women alive: nevirapine 67 969, efavirenz 68 880, difference =  911; birth defects: nevirapine 1128, efavirenz 1187, difference = 59). In sensitivity analysis, the teratogenicity rate with efavirenz had to be 6.3%, or 2.3 times higher than the rate with nevirapine, for the excess number of birth defects to outweigh the additional number of women alive at 10 years.

CONCLUSION

In Côte d'Ivoire, initiating ART with efavirenz instead of nevirapine is likely to substantially increase the number of women alive at 10 years with a smaller potential number of birth defects.

Treating HIV-infected mothers reduces under 5 years of age mortality rates to levels seen in children of HIV-uninfected mothers in rural South Africa

BACKGROUND

Maternal and child survival are highly correlated, but the contribution of HIV infection on this relationship, and in particular the effect of HIV treatment, has not been quantified. We estimate the association between maternal HIV and treatment, and under 5 years of age (under-5) child mortality in a rural population in South Africa.

METHODS

All children born between January 2000 and January 2007 in the Africa Centre Demographic Surveillance Area were included. Maternal HIV status information was available from HIV surveillance; maternal antiretroviral treatment (ART) information from the HIV Treatment Programme database was linked to surveillance data. Mortality rates were computed as deaths per 1,000 person-years observed. Time-varying maternal HIV effect (positive, negative, ART) on under-5 mortality was assessed in Cox regression, adjusting for other factors associated with under-5 mortality.

RESULTS

In total, 9,068 mothers delivered 12,052 children, of whom 947 (7.9%) died before age 5. Infant mortality rate declined by 49% from 69.0 in 2000 to 35.5 in 2006 deaths per 1,000 person-years observed; a significant decline was observed post-ART (2004-2006). The estimated proportion of deaths across all age groups were higher among the children born to the HIV-positive and HIV-not-reported status women than among children of HIV-negative women. Multivariably, mortality in children of mothers on ART was not significantly different from children of HIV-negative mothers (adjusted hazard ratio 1.29, 0.53-3.17; P=0.572).

CONCLUSIONS

These findings highlight the importance of maternal HIV treatment with direct benefits of improved survival among all children under-5. Timely HIV treatment for eligible women is required to benefit both mothers and children.

Under-two child mortality according to maternal HIV status in Rwanda: assessing outcomes within the National PMTCT Program

INTRODUCTION

We sought to compare risk of death among children aged under-2 years born to HIV positive mother (HIV-exposed) and to HIV negative mother (HIV non-exposed), and identify determinants of under-2 mortality among the two groups in Rwanda.

METHODS

In a stratified, two-stage cluster sampling design, we selected mother-child pairs using national Antenatal Care (ANC) registers. Household interview with each mother was conducted to capture socio-demographic data and information related to pregnancy, delivery and post-partum. Data were censored at the date of child death. Using Cox proportional hazard model, we compared the hazard of death among HIV-exposed children and HIV non-exposed children.

RESULTS

Of 1,455 HIV-exposed children, 29 (2.0%; 95% CI: 1.3%-2.7%) died by 6 months compared to 18 children of the 1,565 HIV non-exposed children (1.2%; 95% CI: 0.6%-1.7%). By 9 months, cumulative risks of death were 3.0% (95%; CI: 2.2%-3.9%) and 1.3% (96%; CI: 0.7%-1.8%) among HIV-exposed and HIV non-exposed children, respectively. By 2 years, the hazard of death among HIV-exposed children was more than 3 times higher (aHR:3.5; 95% CI: 1.8-6.9) among HIV-exposed versus non-exposed children. Risk of death by 9-24 months of age was 50% lower among mothers who attended 4 or more antenatal care (ANC) visits (aHR: 0.5, 95% CI: 0.3-0.9), and 26% lower among families who had more assets (aHR: 0.7, 95% CI: 0.5-1.0).

CONCLUSION

Infant mortality was independent of perinatal HIV exposure among children by 6 months of age. However, HIV-exposed children were 3.5 times more likely to die by 2 years. Fewer antenatal visits, lower household assets and maternal HIV seropositive status were associated with increased mortality by 9-24 months.

Measuring and correcting biased child mortality statistics in countries with generalized epidemics of HIV infection

OBJECTIVE

Under Millennium Development Goal 4, countries are required to reduce child mortality by two-thirds between 1990 and 2015. In countries with generalized epidemics of human immunodeficiency virus (HIV) infection, standard statistics based on fertility history may misrepresent progress towards this target owing to the correlation between deaths among mothers and early childhood deaths from acquired immunodeficiency syndrome.

METHODS

To empirically estimate this bias, child mortality data and fertility history, including births to deceased women, were collected through prospective household surveys in eastern Zimbabwe during 1998-2005. A mathematical model was then used to investigate the determinants and temporal dynamics of the bias, first in Zimbabwe and then in other countries with different background mortality rates and HIV-related epidemic profiles.

FINDINGS

According to the empirical data, standard cross-sectional survey statistics underestimated true infant and under-5 mortality by 6.7% and 9.8%, respectively. These estimates were in agreement with the output from the model, in which the bias varied according to the magnitude and stage of the epidemic of HIV infection and background mortality rates. The bias was greater the longer the period elapsed before the survey and in later stages of the epidemic. Bias could substantially distort the measured effect of interventions to reduce non-HIV-related mortality and of programmes to prevent mother-to-child transmission, especially when trends are based on data from a single survey.

CONCLUSION

The correlation between the HIV-related deaths of mothers and their children can bias survey estimates of early child mortality. A mathematical model with a user-friendly interface is available to correct for this bias when measuring progress towards Millennium Development Goal 4 in countries with generalized epidemics of HIV infection.

Impact of HIV/Aids on Child Mortality before the Highly Active Antiretroviral Therapy Era: A Study in Pointe-Noire, Republic of Congo

Few studies have documented the contribution of HIV/AIDS to mortality among children under 15 years. From June 30 to October 19, 2001, all child deaths (n = 588) registered to the morgue and/or hospitals of the city of Pointe-Noire, Congo, were investigated using a combined approach including an interview of relatives and postmortem clinical and biological HIV diagnosis. Twenty-one percent of children were HIV positive, while 10.5% of deaths were attributed to AIDS. The most common causes of death in HIV-infected children were pneumonia (30%), pyrexia (22%), diarrhoea (16%) and wasting syndrome (16%). Infant mortality rate was estimated 6.3 times higher in children born to HIV-infected mothers compared to HIV-uninfected mothers. This study provides a direct measure of HIV/AIDS as impact on child mortality using a rapid and reliable method. A significant number of deaths could be prevented if HIV infection was diagnosed earlier and infants were provided with antiretroviral treatments.

Decline in early life mortality in a high HIV prevalence rural area of South Africa: evidence of HIV prevention or treatment impact?

OBJECTIVE

We present early life mortality rates in a largely rural population with high antenatal HIV prevalence, and investigate temporal and spatial associations with a prevention of mother-to-child transmission (PMTCT) programme, an HIV treatment programme, and maternal HIV.

DESIGN

A retrospective cohort analysis.

METHODS

All births from January 2000 to January 2007 to women in the Africa Centre demographic surveillance were included. Under-two child mortality rates (U2MR) computed as deaths per 1000 live-births per year; factors associated with mortality risk assessed with Weibull regression. Availability of PMTCT (single-dose nevirapine; sdNVP) and antiretroviral therapy (ART) in a programme included in multivariable analysis.

RESULTS

Eight hundred and forty-eight (6.2%) of 13 583 children under 2 years died. Deaths in under-twos declined by 49% between 2001 and 2006, from 86.3 to 44.1 deaths per thousand live-births. Mortality was independently associated with birth season (adjusted hazard ratio 1.16, 95% confidence interval 1.02-1.33), maternal education (1.21, 1.02-1.43), maternal HIV (4.34, 3.11-6.04) and ART availability (0.46, 0.33-0.65). Children born at home (unlikely to have received sdNVP) had a 35% higher risk of dying than children born in a facility where sdNVP was available (1.35, 1.04-1.74). For 2005 births the availability of PMTCT and ART in public health programmes would have explained 8 and 31% of the decline in U2MR since 2000.

CONCLUSION

These findings confirm the importance of maternal survival, and highlight the importance of the PMTCT and especially maternal HIV treatment with direct benefits of improved survival of their young children.

Child survival gains in Tanzania: analysis of data from demographic and health surveys

BACKGROUND

A recent national survey in Tanzania reported that mortality in children younger than 5 years dropped by 24% over the 5 years between 2000 and 2004. We aimed to investigate yearly changes to identify what might have contributed to this reduction and to investigate the prospects for meeting the Millennium Development Goal for child survival (MDG 4).

METHODS

We analysed data from the four demographic and health surveys done in Tanzania since 1990 to generate estimates of mortality in children younger than 5 years for every 1-year period before each survey back to 1990. We estimated trends in mortality between 1990 and 2004 by fitting Lowess regression, and forecasted trends in mortality in 2005 to 2015. We aimed to investigate contextual factors, whether part of Tanzania's health system or not, that could have affected child mortality.

FINDINGS

Disaggregated estimates of mortality showed a sharp acceleration in the reduction in mortality in children younger than 5 years in Tanzania between 2000 and 2004. In 1990, the point estimate of mortality was 141.5 (95% CI 141.5-141.5) deaths per 1000 livebirths. This was reduced by 40%, to reach a point estimate of 83.2 (95% CI 70.1-96.3) deaths per 1000 livebirths in 2004. The change in absolute risk was 58.4 (95% CI 32.7-83.8; p<0.0001). Between 1999 and 2004 we noted important improvements in Tanzania's health system, including doubled public expenditure on health; decentralisation and sector-wide basket funding; and increased coverage of key child-survival interventions, such as integrated management of childhood illness, insecticide-treated nets, vitamin A supplementation, immunisation, and exclusive breastfeeding. Other determinants of child survival that are not related to the health system did not change between 1999 and 2004, except for a slow increase in the HIV/AIDS burden.

INTERPRETATION

Tanzania could attain MDG 4 if this trend of improved child survival were to be sustained. Investment in health systems and scaling up interventions can produce rapid gains in child survival.

Early growth of infants of HIV-infected and uninfected Zambian women

OBJECTIVE

Parental HIV infection may affect even those exposed children who remain uninfected. We investigated early growth, an indicator of overall health, of infants born to Zambian mothers recruited for a study of breastfeeding and postpartum health.

METHODS

HIV-infected and uninfected women in Lusaka were followed regularly from late pregnancy to 16 weeks postpartum. Infant weight and length were measured at birth, 6 and 16 weeks. Infant HIV status could not be specifically determined in this cohort so comparisons were between all infants of HIV-uninfected mothers (n = 184) and those infants of HIV-infected mothers who were known to be alive and showed no clinical evidence of HIV infection at age 2-4 years (n = 85).

RESULTS

Most infants were exclusively or predominantly breastfed until 16 weeks. At all time points infants of HIV-infected mothers tended to have lower weight and length standard deviation (Z) scores (significant for weight at 6 weeks; P = 0.04), even after adjustment for their lower gestational age at birth, compared with infants of uninfected mothers. In multivariate analyses the major factors affecting weight or length at 6 or 16 weeks of age were birth weight or length, and maternal subclinical mastitis, primiparity and weight during pregnancy.

CONCLUSIONS

Early growth of infants of HIV-infected mothers is less than that of uninfected mothers, in part associated with subclinical mastitis, and this effect cannot be overcome with intensive support of mothers to follow international recommendations regarding exclusive breastfeeding.

Preliminary outcomes of a paediatric highly active antiretroviral therapy cohort from KwaZulu-Natal, South Africa

Background

Few studies address the use of paediatric highly active antiretroviral therapy (HAART) in Africa.

Methods

We performed a retrospective cohort study to investigate preliminary outcomes of all children eligible for HAART at Sinikithemba HIV/AIDS clinic in KwaZulu-Natal, South Africa. Immunologic, virologic, clinical, mortality, primary caregiver, and psychosocial variables were collected and analyzed.

Results

From August 31, 2003 until October 31, 2005, 151 children initiated HAART. The median age at HAART initiation was 5.7 years (range 0.3–15.4). Median follow-up time of the cohort after HAART initiation was 8 months (IQR 3.5–13.5). The median change in CD4% from baseline (p < 0.001) was 10.2 (IQR 5.0–13.8) at 6 months (n = 90), and 16.2 (IQR 9.6–20.3) at 12 months (n = 59). Viral loads (VLs) were available for 100 children at 6 months of which 84% had HIV-1 RNA levels ≤ 50 copies/mL. At 12 months, 80.3% (n = 61) had undetectable VLs. Sixty-five out of 88 children (73.8%) reported a significant increase (p < 0.001) in weight after the first month. Eighty-nine percent of the cohort (n = 132) reported ≤ 2 missed doses during any given treatment month (> 95%adherence). Seventeen patients (11.3%) had a regimen change; two (1.3%) were due to antiretroviral toxicity. The Kaplan-Meier one year survival estimate was 90.9% (95%confidence interval (CI) 84.8–94.6). Thirteen children died during follow-up (8.6%), one changed service provider, and no children were lost to follow-up. All 13 deaths occurred in children with advanced HIV disease within 5 months of treatment initiation. In multivariate analysis of baseline variables against mortality using Cox proportional-hazards model, chronic gastroenteritis was associated with death [hazard ratio (HR), 12.34; 95%CI, 1.27–119.71) and an HIV-positive primary caregiver was found to be protective against mortality [HR, 0.12; 95%CI, 0.02–0.88). Age, orphanhood, baseline CD4%, and hemoglobin were not predicators of mortality in our cohort. Fifty-two percent of the cohort had at least one HIV-positive primary caregiver, and 38.4% had at least one primary caregiver also on HAART at Sinikithemba clinic.

Conclusion

This report suggests that paediatric HAART can be effective despite the challenges of a resource-limited setting.

High maternal HIV-1 viral load during pregnancy is associated with reduced placental transfer of measles IgG antibody

BACKGROUND

Studies among HIV-1-infected women have demonstrated reduced placental transfer of IgG antibodies against measles and other pathogens. As a result, infants born to women with HIV-1 infection may not acquire adequate passive immunity in utero and this could contribute to high infant morbidity and mortality in this vulnerable population.

METHODS

To determine factors associated with decreased placental transfer of measles IgG, 55 HIV-1-infected pregnant women who were enrolled in a Nairobi perinatal HIV-1 transmission study were followed. Maternal CD4 count, HIV-1 viral load, and HIV-1-specific gp41 antibody concentrations were measured antenatally and at delivery. Measles IgG concentrations were assayed in maternal blood and infant cord blood obtained during delivery to calculate placental antibody transfer.

RESULTS

Among 40 women (73%) with positive measles titers, 30 (75%) were found to have abnormally low levels of maternofetal IgG transfer (<95%). High maternal HIV-1 viral load at 32 weeks' gestation and at delivery was associated with reductions in placental transfer (P < 0.0001 and P = 0.0056, respectively) and infant measles IgG concentrations in cord blood (P < 0.0001 and P = 0.0073, respectively). High maternal HIV-1-specific gp41 antibody titer was also highly correlated with both decreased placental transfer (P = 0.0080) and decreased infant IgG (P < 0.0001).

CONCLUSIONS

This is the first study to evaluate the relationship between maternal HIV-1 viremia, maternal HIV-1 antibody concentrations, and passive immunity among HIV-1-exposed infants. These data support the hypothesis that high HIV-1 viral load during the last trimester may impair maternofetal transfer of IgG and increases risk of measles and other serious infections among HIV-1-exposed infants.

Does severity of HIV disease in HIV-infected mothers affect mortality and morbidity among their uninfected infants?

BACKGROUND

Rates of perinatal human immunodeficiency virus (HIV) transmission are higher among HIV-infected mothers with more advanced disease, but effects of maternal disease on HIV-uninfected offspring are unclear. We investigated the hypothesis that the severity of HIV disease and immune dysfunction among mothers is associated with increased morbidity and mortality among their uninfected infants.

METHODS

In a birth cohort of 620 HIV-uninfected infants born to HIV-infected mothers in Lusaka, Zambia, we investigated associations between markers of more advanced maternal HIV disease and child mortality, hospital admissions, and infant weight through 4 months of age.

RESULTS

Mortality in the cohort of uninfected infants was 4.6% (95% confidence interval [CI], 2.8-6.3) through 4 months of age. Infants of mothers with CD4+ T cell counts of <350 cells/microL were more likely to die (hazard ratio [HR], 2.87; 95% CI, 1.03-8.03) and were more likely to be hospitalized (HR, 2.28; 95% CI, 1.17-4.45), after adjusting for other factors, including maternal death and low birth weight. The most common cause of infant death and hospitalization was pneumonia and/or sepsis. A maternal viral load of >100,000 copies/mL was associated with significantly lower child weight through 4 months of age.

CONCLUSION

Children born to HIV-infected mothers with advanced disease who escaped perinatal or early breastfeeding-related HIV infection are nonetheless at high risk of mortality and morbidity during the first few months of life. HIV-related immunosuppression appears to have adverse consequences for the health of infants, in addition to risks of vertical transmission.

Methods to estimate the number of orphans as a result of AIDS and other causes in Sub-Saharan Africa

OBJECTIVE

To derive methods to estimate and project the fraction of children orphaned by AIDS and other causes.

METHODS

HIV/AIDS affects orphan numbers through increased adult and child mortality and reduced fertility of HIV-positive women. We extend an epidemiologic and demographic model used previously to estimate maternal orphans to paternal orphans. We account for the impact of HIV/AIDS on child survival by modeling the HIV status of the partners of men who die of AIDS or other causes based on data on the concordance of heterosexual partners. Subsequently, the proportion of orphans whose parents have both died is predicted by a regression model fitted to orphanhood data from 34 national demographic and health surveys (DHSs). The approach is illustrated with an application to Tanzania and compared with DHS estimates for the years 1992 and 1999.

RESULTS

Projections of the number and age distribution of orphans using these methods agree with survey data for Tanzania. They show the rise in orphanhood over the last decade that has resulted from the HIV epidemic.

CONCLUSIONS

The methods allow estimation of the numbers of children whose mother, father, or both parents have died for countries with generalized heterosexual HIV epidemics. These methods have been used to produce orphan estimates for high-prevalence countries published by Joint United Nations Program on HIV/AIDS, World Health Organization, United Nations Children's Fund, and US Agency for International Development in 2002 and 2004.

HIV and mortality of mothers and children: evidence from cohort studies in Uganda, Tanzania, and Malawi

BACKGROUND

The steady decline in child mortality observed in most African countries through the 1960s, 1970s, and 1980s has stalled in many countries in the 1990s because of the AIDS epidemic. However, the census and household survey data that generally are used to produce estimates of child mortality do not permit precise measures of the adverse effect of HIV on child mortality.

METHODS

To calculate excess risks of child mortality as the result of maternal HIV status, we used pooled data from 3 longitudinal community-based studies that classified births by the mother's HIV status. We also estimated excess risks of child death caused by increased mortality among mothers. The joint effects of maternal HIV status and maternal survival were quantified using multivariate techniques in a survival analysis.

RESULTS

Our analysis shows that the excess risk of death associated with having an HIV-positive mother is 2.9 (95% confidence interval = 2.3-3.6), and this effect lasts throughout childhood. The excess risk associated with a maternal death is 3.9 (2.8-5.5) in the 2-year period centered on the mother's death, with children of both infected and uninfected mothers experiencing higher mortality risks at this time.

CONCLUSION

HIV impacts on child mortality directly through transmission of the virus to newborns by infected mothers and indirectly through higher child mortality rates associated with a maternal death.

Estimating the net effect of HIV on child mortality in African populations affected by generalized HIV epidemics

For a given prevalence, HIV has a relatively higher impact on child mortality when mortality from other causes is low. To project the effect of the epidemic on child mortality, it is necessary to estimate a realistic schedule of "net" age-specific mortality rates that would operate if HIV were the only cause of child death observable. We assume that this net pattern would be independent of mortality from other causes. We used African studies that measured the survival of HIV-infected children (direct data) or survival of children of HIV-infected mothers (indirect data). We developed a mathematic procedure to estimate the mortality of infected children from indirect data sources and obtained net HIV mortality patterns for each study population. The net age-specific HIV mortality pattern for infected children can be described by a double Weibull curve fitted to empiric data; this gives a functional representation of age-specific mortality rates that decline after infancy and rise in the preteens. The fitted curve that we would expect if HIV were the only effective cause of death shows 67% net survival at 1 year and 39% at 5 years. The curve also predicts 13% net survival at 10 years using constraints based on survival of infected adults.

Child mortality and HIV infection in Africa: a review

OBJECTIVES

To review the available data relating to child mortality in Africa by the HIV infection status of mothers and children.

RESULTS

Child survival is influenced by the HIV epidemic through several mechanisms. Mother-to-child transmission of HIV ranges from 15 to 45%, with up to 15-20% resulting from breastfeeding. HIV-infected children have high mortality rates. For example, a recent community-based study in Rakai, Uganda, showed 2-year mortality rates of 547, 166 and 128 per thousand among HIV-infected children, HIV-negative children of HIV-positive mothers, and HIV-negative children of HIV-negative women, respectively. Child mortality estimates from community-based cohorts demonstrate that the children of HIV-infected mothers have higher mortality rates than the children of uninfected mothers, and that child mortality is closely linked with maternal health status, but because the proportion of vertically infected children is unknown, the value of these studies is limited. Models that use HIV surveillance data together with a set of assumptions indicate that child mortality caused by HIV/AIDS has increased throughout the 1990s to reach close to 10% by 2002.

CONCLUSION

Both disparate trends in HIV prevalence and varying levels of non-HIV-associated child mortality will ensure very different impacts in different countries. To improve the projections of the overall effect that the HIV epidemic will have on child mortality at the population level in countries with generalized epidemics, reliable age-specific mortality rates in infected and uninfected children are needed.

Impact of the HIV epidemic on population and household structure: the dynamics and evidence to date

BACKGROUND

HIV is contracted most frequently at birth and during early adulthood. The epidemic may thus impact the demographic structure and the household structure of affected populations.

METHODS

This paper reviews earlier evidence of such an impact, uses demographic theory to anticipate its changes over time, and reviews the most recent evidence for indications of these changes.

RESULTS

Modest increases in the male : female ratio are beginning to show within certain age groups only (approximately 15% among 25-34 year olds). Similarly sized increases in the proportion of 15-29 year olds relative to 30-54 year olds are observed in some age pyramids. These 'youth bulges' are expected to fade out, whereas an aging effect phases in with the fertility impact of the epidemic. In the longer run, the size of all age groups will be reduced, but relatively less so for middle-aged adults. Proportions of orphans and widows have increased in the most affected countries. Fewer remarriage probabilities for widows were observed. Resulting increases in the proportion of female-headed households should only be temporary, as female mortality is catching up with male mortality. The number of double orphans is beginning to increase, but overall, orphans continue to live predominantly with a family member, most often the grandparents if not with the surviving parent.

CONCLUSION

To date, the epidemic's impact on the population and household structure has been limited by demographic (aging) and social (adaptive movements of kin across households) processes that contribute to diffuse the epidemic throughout the entire population and all households.