Demographic impact of HIV infection in rural Rakai district, Uganda: results of a population-based cohort study

Estimation of cause-specific mortality in Rakai, Uganda, using verbal autopsy 1999-2019

BACKGROUND

There are scant data on the causes of adult deaths in sub-Saharan Africa. We estimated the level and trends in adult mortality, overall and by different causes, in rural Rakai, Uganda, by age, sex, and HIV status.

OBJECTIVES

To estimate and analyse adult cause-specific mortality trends in Rakai, Uganda.

METHODOLOGY

Mortality information by cause, age, sex, and HIV status was recorded in the Rakai Community Cohort study using verbal autopsy interviews, HIV serosurveys, and residency data. We estimated the average number of years lived in adulthood. Using demographic decomposition methods, we estimated the contribution of each cause of death to adult mortality based on the average number of years lived in adulthood.

RESULTS

Between 1999 and 2019, 63082 adults (15-60 years) were censused, with 1670 deaths registered. Of these, 1656 (99.2%) had completed cause of death data from verbal autopsy. The crude adult death rate was 5.60 (95% confidence interval (CI): 5.33-5.87) per 1000 person-years of observation (pyo). The crude death rate decreased from 11.41 (95% CI: 10.61-12.28) to 3.27 (95% CI: 2.89-3.68) per 1000 pyo between 1999-2004 and 2015-2019. The average number of years lived in adulthood increased in people living with HIV and decreased in HIV-negative individuals between 2000 and 2019. Communicable diseases, primarily HIV and Malaria, had the biggest decreases, which improved the average number of years lived by approximately extra 12 years of life in females and 6 years in males. There were increases in deaths due to non-communicable diseases and external causes, which reduced the average number of years lived in adulthood by 2.0 years and 1.5 years in females and males, respectively.

CONCLUSION

There has been a significant decline in overall mortality from 1999 to 2019, with the greatest decline seen in people living with HIV since the availability of antiretroviral therapy in 2004. By 2020, the predominant causes of death among females were non-communicable diseases, with external causes of death dominating in males.

The rural Uganda non-communicable disease (RUNCD) study: prevalence and risk factors of self-reported NCDs from a cross sectional survey

Background

Non-communicable diseases (NCDs) are an increasing global concern, with morbidity and mortality largely occurring in low- and middle-income settings. We established the prospective Rural Uganda Non-Communicable Disease (RUNCD) cohort to longitudinally characterize the NCD prevalence, progression, and complications in rural Africa.

Methods

We conducted a population-based census for NCD research. We systematically enrolled adults in each household among three sub-counties of the larger Nakaseke Health district and collected baseline demographic, health status, and self-reported chronic disease information. We present our data on self-reported chronic disease, as stratified by age, sex, educational attainment, and sub-county.

Results

A total of 16,694 adults were surveyed with 10,563 (63%) respondents enrolled in the self-reported study. Average age was 37.8 years (SD = 16.5) and 45% (7481) were male. Among self-reported diseases, hypertension (HTN) was most prevalent (6.3%). 1.1% of participants reported a diagnosis of diabetes, 1.1% asthma, 0.7% COPD, and 0.4% kidney disease. 2.4% of the population described more than one NCD. Self-reported HTN was significantly higher in the peri-urban subcounty than in the other two rural sub-counties (p < 0.001); diagnoses for all other diseases did not differ significantly between sub-counties. Odds for self-reported HTN increased significantly with age (OR = 1.87 per 10 years of age, 95% CI 1.78–1.96). Male sex was associated with lower odds of reporting asthma (OR = 0.53, 95% CI 0.34–0.82) or HTN (OR = 0.31, 95% CI 0.26–0.40).

Conclusions

The RUNCD will establish one of the largest NCD patient cohorts in rural Africa. First analysis highlights the feasibility of systematically enrolling large numbers of adults living in a rural Ugandan district. In addition, our study demonstrates low levels of self-reported NCDs compared to the nation-wide established levels, emphasizing the need to better educate, characterize, and care for the majority of rural communities.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12123-7.

Health and demographic surveillance systems in low- and middle-income countries: history, state of the art and future prospects

Health and Demographic Surveillance Systems (HDSS) have been developed in several low- and middle-income countries (LMICs) in Africa and Asia. This paper reviews their history, state of the art and future potential and highlights substantial areas of contribution by the late Professor Peter Byass.Historically, HDSS appeared in the second half of the twentieth century, responding to a dearth of accurate population data in poorly resourced settings to contextualise the study of interventions to improve health and well-being. The progress of the development of this network is described starting with Pholela, and progressing through Gwembe, Balabgarh, Niakhar, Matlab, Navrongo, Agincourt, Farafenni, and Butajira, and the emergence of the INDEPTH Network in the early 1990'sThe paper describes the HDSS methodology, data, strengths, and limitations. The strengths are particularly their temporal coverage, detail, dense linkage, and the fact that they exist in chronically under-documented populations in LMICs where HDSS sites operate. The main limitations are generalisability to a national population and a potential Hawthorne effect, whereby the project itself may have changed characteristics of the population.The future will include advances in HDSS data harmonisation, accessibility, and protection. Key applications of the data are to validate and assess bias in other datasets. A strong collaboration between a national HDSS network and the national statistics office is modelled in South Africa and Sierra Leone, and it is possible that other low- to middle-income countries will see the benefit and take this approach.

Age patterns of HIV incidence in eastern and southern Africa: a modelling analysis of observational population-based cohort studies

BACKGROUND

As the HIV epidemic in sub-Saharan Africa matures, evidence about the age distribution of new HIV infections and how this distribution has changed over the epidemic is needed to guide HIV prevention. We aimed to assess trends in age-specific HIV incidence in six population-based cohort studies in eastern and southern Africa, reporting changes in mean age at infection, age distribution of new infections, and birth cohort cumulative incidence.

METHODS

We used a Bayesian model to reconstruct age-specific HIV incidence from repeated observations of individuals' HIV serostatus and survival collected among population HIV cohorts in rural Malawi, South Africa, Tanzania, Uganda, and Zimbabwe, in a collaborative analysis of the ALPHA network. We modelled HIV incidence rates by age, time, and sex using smoothing splines functions. We estimated incidence trends separately by sex and study. We used estimated incidence and prevalence results for 2000-17, standardised to study population distribution, to estimate mean age at infection and proportion of new infections by age. We also estimated cumulative incidence (lifetime risk of infection) by birth cohort.

FINDINGS

Age-specific incidence declined at all ages, although the timing and pattern of decline varied by study. The mean age at infection was higher in men (cohort mean 27·8-34·6 years) than in women (24·8-29·6 years). Between 2000 and 2017, the mean age at infection per cohort increased slightly: 0·5 to 2·8 years among men and -0·2 to 2·5 years among women. Across studies, between 38% and 63% (cohort medians) of the infections in women were among those aged 15-24 years and between 30% and 63% of infections in men were in those aged 20-29 years. Lifetime risk of HIV declined for successive birth cohorts.

INTERPRETATION

HIV incidence declined in all age groups and shifted slightly to older ages. Disproportionate new HIV infections occur among women aged 15-24 years and men aged 20-29 years, supporting focused prevention in these groups. However, 40-60% of infections were outside these ages, emphasising the importance of providing appropriate HIV prevention to adults of all ages.

FUNDING

Bill & Melinda Gates Foundation.

Population-level adult mortality following the expansion of antiretroviral therapy in Rakai, Uganda

There are limited data on the impact of antiretroviral therapy (ART) on population-level adult mortality in sub-Saharan Africa. We analysed data for 2000-14 from the Rakai Community Cohort Study (RCCS) in Uganda, where free ART was scaled up after 2004. Using non-parametric and parametric (Weibull) survival analysis, we estimated trends in average person-years lived between exact ages 15 and 50, per capita life-years lost to HIV, and the mortality hazards of people living with HIV (PLHIV). Between 2000 and 2014, average adult life-years lived before age 50 increased significantly, from 26.4 to 33.5 years for all women and from 28.6 to 33.8 years for all men. As of 2014, life-years lost to HIV had declined significantly, to 1.3 years among women and 0.4 years among men. Following the roll-out of ART, mortality reductions among PLHIV were initially larger in women than men, but this is no longer the case.

A combination intervention addressing sexual risk-taking behaviors among vulnerable women in Uganda: study protocol for a cluster randomized clinical trial

BACKGROUND

Sub-Saharan Africa (SSA) has the highest number of people living with HIV/AIDS, with Nigeria, South Africa, and Uganda accounting for 48% of new infections. A systematic review of the HIV burden among women engaged in sex work (WESW) in 50 low- and middle-income countries found that they had increased odds of HIV infection relative to the general female population. Social structural factors, such as the sex work environment, violence, stigma, cultural issues, and criminalization of sex work are critical in shaping sexually transmitted infection (STI)/HIV risks among WESW and their clients in Uganda. Poverty is the most commonly cited reason for involvement in sex work in SSA. Against this backdrop, this study protocol describes a randomized controlled trial (RCT) that tests the impact of adding economic empowerment to traditional HIV risk reduction (HIVRR) to reduce new incidence of STIs and HIV among WESW in Rakai and the greater Masaka regions in Uganda.

METHODS

This three-arm RCT will evaluate the efficacy of adding savings, financial literacy and vocational training/mentorship to traditional HIVRR on reducing new incidence of STI infections among 990 WESW across 33 hotspots. The three arms (n = 330 each) are: 1) Control group: only HIVRR versus 2) Treatment group 1: HIVRR plus Savings plus Financial Literacy (HIVRR + S + FL); and 3) Treatment group 2: HIVRR plus S plus FL plus Vocational Skills Training and Mentorship (V) (HIVRR + S + FL + V). Data will be collected at baseline (pre-test), 6, 12, 18 and 24-months post-intervention initiation. This study will use an embedded experimental mixed methods design where qualitative data will be collected post-intervention across all conditions to explore participant experiences.

DISCUSSION

When WESW have access to more capital and/or alternative forms of employment and start earning formal income outside of sex work, they may be better able to improve their skills and employability for professional advancement, thereby reducing their STI/HIV risk. The study findings may advance our understanding of how best to implement gender-specific HIV prevention globally, engaging women across the HIV treatment cascade. Further, results will provide evidence for the intervention's efficacy to reduce STIs and inform implementation sustainability, including costs and cost-effectiveness.

TRIAL REGISTRATION

ClinicalTrials.gov , ID: NCT03583541 .

Migration, Sexual Behavior and the Risk of HIV in Kenya

The association of migration with AIDS in sub-Saharan Africa is well documented, yet the social and behavioral mechanisms underlying this relationship remain poorly understood. Using data from the 1993 Kenya Demographic and Health Survey, this article examines whether migrants are more likely than nonmigrants to have multiple recent sexual partners and not use condoms with those partners. Results indicate that migration is a critical factor in high-risk sexual behavior and that its importance varies by gender and by the direction of movement. Independent of marital and cohabitation status, social milieu, awareness of AIDS, and other crucial influences on sexual behavior, male migrants between urban areas and female migrants within rural areas are much more likely than nonmigrant counterparts to engage in sexual practices conducive to HIV infection. In rural areas, migrants from urban places are more likely than nonmigrants to practice high-risk sex. Given the predominance of men in urban migration and the large volume of circulatory movement between urban and rural areas, these results have serious implications for HIV transmission throughout Kenya.

Couple perspectives on unintended pregnancy in an area with high HIV prevalence: A qualitative analysis in Rakai, Uganda

Understanding how couples perceive a recent unintended pregnancy in the context of HIV infection and high levels of gender inequality may provide insights for prevention of undesired pregnancy. We used data from 24 in-depth interviews with 8 HIV-serodiscordant and 4 seroconcordant couples living in rural Uganda and interviewed separately; between 15 and 49 years and one or both identified the pregnancy as unintended. A dyadic analysis was performed to understand each partner's perspectives on experiences of a specific pregnancy. We used the social-ecological model to guide the analysis. Issues of agency were commonly invoked in describing pregnancy. Women often cited factors that demonstrated a lack of control when making decisions about continuing the pregnancy. Men often expressed a lack of agency or control over preventing their female partner from becoming pregnant. There was much disagreement between partners about intentions regarding the specific pregnancy. Likewise, lack of communication about child spacing and pregnancy intentions was common among couples. HIV serostatus played a role in some discussions of pregnancy intention among serodiscordant couples. This qualitative analysis supports prior quantitative research on the complexity of pregnancy intentions. A lack of agency at the individual level was compounded by a lack of communication between partners.

Facing HIV infection and unintended pregnancy: Rakai, Uganda, 2001-2013

Background

Unintended pregnancy is a persistent and global issue with consequences for the health and well-being of mothers and babies. The aim of this paper is to examine unintended pregnancy over time in the context of substantial human immunodeficiency virus (HIV) prevalence and increasing access to anti-retro viral therapy (ART).

Method

Data are from the Rakai Community Cohort Study (RCCS) – a cohort of communities with 10,000–12,000 adults, ages 15–49, in Rakai District, Uganda. We examined prevalence of current pregnancies over time, intended pregnancy, and unintended pregnancies (unwanted, mistimed, ambivalent). We then examined risk factors for the different categories of unintended pregnancy among women who were currently pregnant. The full sample included 32,205 observations over 13 years.

Results

The prevalence of mistimed pregnancy and unwanted pregnancy both decreased significantly over time (p < .001). The prevalence of current pregnancies and intended pregnancy showed no significant changes over the thirteen year period. The same overall pattern was found when only examining HIV positive women in the sample; however, the trends were not significant. Out of the 2820 current pregnancies reported, 54.4% were intended, 29.8% were mistimed, 13.2% were unwanted, and 2.5% were ambivalent. After controlling for other predictors, HIV status had no independent effect on mistimed pregnancy but had a significant effect on unwanted pregnancy (RRR = 2.44, 95% CI = 1.65–3.61, p < .001] and ambivalent pregnancy [RRR = 2.07; CI: 1.03 to 4.18, p = 0.041]. In 2004, after the introduction of ART, there was a decreased risk in unintended pregnancy [RR = 0.75; CI: 0.66 to 0.84, p < .001]. Women with a secondary education or higher also had a decreased risk in unintended pregnancy [RR = 0.70; CI: 0.70 to 0.92, p = 0.002].

Discussion

HIV was an important predictor of unwanted pregnancy. Unintended pregnancy decreased in the sample over time which may be due to an increase in ART availability and rising levels of education.

The Network for Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA): Data on mortality, by HIV status and stage on the HIV care continuum, among the general population in seven longitudinal studies between 1989 and 2014

Timely progression of people living with HIV (PLHIV) from the point of infection through the pathway from diagnosis to treatment is important in ensuring effective care and treatment of HIV and preventing HIV-related deaths and onwards transmission of infection.  Reliable, population-based estimates of new infections are difficult to obtain for the generalised epidemics in sub-Saharan Africa.  Mortality data indicate disease burden and, if disaggregated along the continuum from diagnosis to treatment, can also reflect the coverage and quality of different HIV services.  Neither routine statistics nor observational clinical studies can estimate mortality prior to linkage to care nor following disengagement from care.  For this, population-based data are required. The Network for Analysing Longitudinal Population-based HIV/AIDS data on Africa brings together studies in Kenya, Malawi, South Africa, Tanzania, Uganda, and Zimbabwe.  Eight studies have the necessary data to estimate mortality by HIV status, and seven can estimate mortality at different stages of the HIV care continuum.  This data note describes a harmonised dataset containing anonymised individual-level information on survival by HIV status for adults aged 15 and above. Among PLHIV, the dataset provides information on survival during different periods: prior to diagnosis of infection; following diagnosis but before linkage to care; in pre-antiretroviral treatment (ART) care; in the first six months after ART initiation; among people continuously on ART for 6+ months; and among people who have ever interrupted ART.

Longitudinal evaluation of aflatoxin exposure in two cohorts in south-western Uganda

Aflatoxins (AF) are a group of mycotoxins. AF exposure causes acute and chronic adverse health effects such as aflatoxicosis and hepatocellular carcinoma in human populations, especially in the developing world. In this study, AF exposure was evaluated using archived serum samples from human immunodeficiency virus (HIV)-seronegative participants from two cohort studies in south-western Uganda. AFB1-lysine (AFB-Lys) adduct levels were determined via HPLC fluorescence in a total of 713 serum samples from the General Population Cohort (GPC), covering eight time periods between 1989 and 2010. Overall, 90% (642/713) of the samples were positive for AFB-Lys and the median level was 1.58 pg mg(-1) albumin (range = 0.40-168 pg mg(-1) albumin). AFB-Lys adduct levels were also measured in a total of 374 serum samples from the Rakai Community Cohort Study (RCCS), across four time periods between 1999 and 2003. The averaged detection rate was 92.5% (346/374) and the median level was 1.18 pg mg(-1) albumin (range = 0.40-122.5 pg mg(-1) albumin). In the GPC study there were no statistically significant differences between demographic parameters, such as age, sex and level of education, and levels of serum AFB-Lys adduct. In the RCCS study, longitudinal analysis using generalised estimating equations revealed significant differences between the adduct levels and residential areas (p = 0.05) and occupations (p = 0.02). This study indicates that AF exposure in people in two populations in south-western Uganda is persistent and has not significantly changed over time. Data from one study, but not the other, indicated that agriculture workers and rural area residents had more AF exposure than those non-agricultural workers and non-rural area residents. These results suggest the need for further study of AF-induced human adverse health effects, especially the predominant diseases in the region.

How have ART treatment programmes changed the patterns of excess mortality in people living with HIV? Estimates from four countries in East and Southern Africa

Background

Substantial falls in the mortality of people living with HIV (PLWH) have been observed since the introduction of antiretroviral therapy (ART) in sub-Saharan Africa. However, access and uptake of ART have been variable in many countries. We report the excess deaths observed in PLWH before and after the introduction of ART. We use data from five longitudinal studies in Malawi, South Africa, Tanzania, and Uganda, members of the network for Analysing Longitudinal Population-based HIV/AIDS data on Africa (ALPHA).

Methods

Individual data from five demographic surveillance sites that conduct HIV testing were used to estimate mortality attributable to HIV, calculated as the difference between the mortality rates in PLWH and HIV-negative people. Excess deaths in PLWH were standardized for age and sex differences and summarized over periods before and after ART became generally available. An exponential regression model was used to explore differences in the impact of ART over the different sites.

Results

127,585 adults across the five sites contributed a total of 487,242 person years. Before the introduction of ART, HIV-attributable mortality ranged from 45 to 88 deaths per 1,000 person years. Following ART availability, this reduced to 14–46 deaths per 1,000 person years. Exponential regression modeling showed a reduction of more than 50% (HR =0.43, 95% CI: 0.32–0.58), compared to the period before ART was available, in mortality at ages 15–54 across all five sites.

Discussion

Excess mortality in adults living with HIV has reduced by over 50% in five communities in sub-Saharan Africa since the advent of ART. However, mortality rates in adults living with HIV are still 10 times higher than in HIV-negative people, indicating that substantial improvements can be made to reduce mortality further. This analysis shows differences in the impact across the sites, and contrasts with developed countries where mortality among PLWH on ART can be similar to that of the general population. Further research is urgently needed to establish why the different impacts on mortality were observed and how the care and treatment programmes in these countries can be more effective in reducing mortality further.

HIV, poverty and women

This review examines the interactions of financial status and HIV and its implications for women. MEDLINE and Google scholar were searched using the keywords 'women', 'poverty' and 'HIV' in any field of the article. The search was limited to articles published in English over the last 10 years. The first section of the article tries to establish whether poverty or wealth is a risk factor for HIV. There is credible evidence for both arguments. While wealth shows an increased risk for both sexes, poverty places women at a special disadvantage. The second section explains how the financial status interacts with other 'non biological' factors to put women at increased risk. While discrimination based on these factors disadvantage women, there are some paradoxical observations that do not fit with the traditional line of explanation (e.g. paradoxical impact of wealth and education on HIV). The final section assesses the impact of HIV in driving poverty and the role of women in interventional programmes. The specific impact of poverty on females in families living with HIV is less explored. Though microfinance initiatives to empower women are a good idea in theory, the actual outcome of such a programme is less convincing.

Incidence of orphanhood before and after implementation of a HIV care programme in Rakai, Uganda: Alpha Network HIV Supplement

OBJECTIVE

To compare the incidence of orphanhood among children <15 years of age before and after implementing HIV care in Rakai, Uganda.

METHODS

Annual household censuses and surveys were conducted on January 2001 to September 2009 in a community cohort, where HIV care including antiretroviral therapy (ART) started in June 2004. Data included parental survival of children aged 0-14 years and HIV status from consenting adults aged 15-49 years. The incidence of orphanhood was estimated as the number of new orphans divided by person-years, determined during three time periods: Pre-HIV care roll-out (January 2001-June 2003) 1-3 years before the advent of HIV care in Rakai programme, HIV care transition from September 2003-May 2006, and the expanded HIV care period from August 2006-September 2009. Poisson regression was used to estimate incidence rate ratios (IRR) of orphanhood and 95% confidence intervals, and the Population attributable fraction (PAF) of incident orphanhood due to HIV+ parental status was estimated as pd*(RR-1)/RR.

RESULTS

A total of 20,823, 21,770 and 23,700 children aged 0-14 years were censused at the three periods, respectively. The prevalence of orphanhood significantly declined; 17.2% during Pre-HIV care roll-out, 16.0% at HIV care transition and 12.6% at expanded HIV care period (chi2 trend, P < 0.0001). The incidence of orphanhood also declined significantly with increasing HIV care from 2.10/100 person-years (py), 1.57/100 py and 1.07/100 py (chi2 trend, P < 0.0001). The largest declines were observed among children with HIV+ parent(s), 8.2/100 pyr, 5.2/100 pys and 3.4/100 pyr. PAF also declined from 35.3% in the pre-HIV care to 27.6% in the expanded HIV care periods.

CONCLUSION

After the availability of ART, there was a decline in PAF of incident orphanhood due to parental HIV+ status, and in the incidence of orphanhood especially among children with HIV-infected parents.

More on the cohort-component model of population projection in the context of HIV/AIDS: A Leslie matrix representation and new estimates

This article presents an extension of the cohort-component model of population projection (CCMPP) first formulated by Heuveline (2003) that is capable of modeling a population affected by HIV. Heuveline proposes a maximum likelihood approach to estimate the age profile of HIV incidence that produced the HIV epidemics in East Africa during the 1990s. We extend this work by developing the Leslie matrix representation of the CCMPP, which greatly facilitates the implementation of the model for parameter estimation and projection. The Leslie matrix also contains information about the stable tendencies of the corresponding population, such as the stable age distribution and time to stability. Another contribution of this work is that we update the sources of data used to estimate the parameters, and use these data to estimate a modified version of the CCMPP that includes (estimated) parameters governing the survival experience of the infected population. A further application of the model to a small population with high HIV prevalence in rural South Africa is presented as an additional demonstration. This work lays the foundation for development of more robust and flexible Bayesian estimation methods that will greatly enhance the utility of this and similar models.

Timing is everything: international variations in historical sexual partnership concurrency and HIV prevalence

BACKGROUND

Higher prevalence of concurrent partnerships is one hypothesis for the severity of the HIV epidemic in the countries of Southern Africa. But measures of the prevalence of concurrency alone do not adequately capture the impact concurrency will have on transmission dynamics. The importance of overlap duration and coital exposure are examined here.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted a comparison of data from three studies of sexual behavior carried out in the early 1990s in Uganda, Thailand and the US. Using cumulative concurrency measures, the three countries appeared somewhat similar. Over 50% of both Thai and Ugandan men reported a concurrency within the last three partnerships and over 20% reported a concurrency in the last year, the corresponding rates among US men were nearly 20% for Blacks and Hispanics, and about 10% for other racial/ethnic groups. Concurrency measures that were more sensitive to overlap duration, however, showed large differences. The point prevalence of concurrency on the day of interview was over 10% among Ugandan men compared to 1% for Thai men. Ugandan concurrencies were much longer duration - a median of about two years - than either the Thai (1 day) or US concurrencies (4-9 months across all groups), and involved 5-10 times more coital risk exposure with the less frequent partner. In the US, Blacks and Hispanics reported higher prevalence, longer duration and greater coital exposure than Whites, but were lower than Ugandans on nearly every measure. Together, the differences in the prevalence, duration and coital exposure of concurrent partnerships observed align with the HIV prevalence differentials seen in these populations at the time the data were collected.

CONCLUSIONS/SIGNIFICANCE

There were substantial variations in the patterns of concurrent partnerships within and between populations. More long-term overlapping partnerships, with regular coital exposure, were found in populations with greater HIV epidemic severity.

Determinants of project success among HIV/AIDS nongovernmental organizations (NGOs) in Rakai, Uganda

SUMMARY

The aim of the study was to identify the main determinants of grassroots project success among HIV/AIDS NGOs operating in Rakai, Uganda. It was a cross-sectional study using face-to-face interviews in a mixed-methods approach among community members and NGOs involved in providing HIV/AIDS and related health services. The study found that the success of grassroots projects of HIV/AIDS NGOs essentially relies on adequate financial resources, competent human resources, strong organizational leadership, and NGO networking. These data suggest that to increase grassroots project success, HIV and AIDS NGOs in Rakai need to improve not only the budget base and human capacities but as well decision-making processes, organizational vision, mission and strategies, gender allocation in staffing, and beneficiary involvement.

Non-vertical HIV transmission to children in sub-Saharan Africa

This review considers whether HIV prevalence data on children in sub-Saharan Africa support the hypothesis that blood exposures account for a large proportion of HIV infections in Africa. Data from a systematic search on HIV-infected children support two analyses. In 25 studies where the mothers' HIV status was not matched with data on each child (excluding non-representative samples of children), the observed prevalence in children in 20 studies was greater than expected from vertical transmission. The population-weighted difference – 1.3% – was approximately one-third of observed prevalence in children. In 32 studies that match HIV-positive children with HIV-negative mothers, 406 discordant mother–child pairs were identified, and in studies identifying at least five non-vertical infections in children, 17.5% of HIV-positive children had HIV-negative mothers. In discussing an important role for unsafe health care in exceptionally rapid HIV transmission in Africa, leading AIDS researchers cite low HIV prevalence in children not yet sexually active. The assumption that childhood HIV prevalence would increase with age in children, if injections transmitted HIV is shown to be erroneous; it fails to account for early mortality in HIV-positive children. Evidence of child-to-child HIV transmission supports the theory that nosocomial infections are important to the AIDS pandemic, and procedures more prevalent than blood transfusions, such as injections, are likely involved.

The long-term social and economic impact of HIV on the spouses of infected individuals in northern Malawi

OBJECTIVE

To assess the social and economic impact of HIV-related illness and death on the spouses of HIV-infected individuals.

METHODS

From population-based surveys in the 1980s in Karonga district, northern Malawi, 197 'index individuals' were identified as HIV-positive. A total of 396 HIV-negative 'index individuals' were selected as a comparison group. These individuals, and their spouses and children, were followed up in 1998-2000, in a retrospective cohort study. All analyses compared spouses of HIV-positive indexes with those of HIV-negative indexes.

RESULTS

By 1998-2000, most marriages involving an HIV-positive index individual had ended in widowhood. Twenty-Six percent of the wives of HIV-positive index men experienced household dissolution precipitated by widowhood, compared with 5% of the wives of HIV-negative index men. Corresponding percentages for husbands of index women were 14% and 1%. Widow inheritance was uncommon. The remarriage rate among separated or widowed wives of HIV-positive index men was half that of such wives of HIV-negative index men. About 30% of surviving wives of HIV-positive index men were household heads at the time of follow-up, compared with 5% of such wives of HIV-negative index men. Almost all these women were widows who lost their husband when >35 years old, and they had relatively few household assets.

CONCLUSIONS

The social and economic impact of HIV on the spouses of HIV-infected individuals in rural northern Malawi is substantial. Interventions that strengthen society's ability to absorb and support widows and widowers, and their dependents, without necessarily involving the traditional coping mechanism of remarriage, are essential.

The estimated burden of HIV/AIDS in Uganda, 2005-2010

OBJECTIVES

To estimate the burden of HIV disease in Uganda and the effect of HIV/AIDS control programmes to mitigate it.

DESIGN

Mathematical modelling and projecting using surveillance and census data.

METHODS

Using antenatal clinic surveillance (1986-2002) and a recent population-based survey (2004-2005) data, we modelled the adult national HIV prevalence over time (1981-2004), and kept prevalence constant at 6.4% for the years 2004-2010. Using Spectrum software and census data, we estimated the national burden of HIV disease and the effect of selected HIV-related prevention and treatment programmes.

RESULTS

In 2005, we estimated that there were 135,300 new HIV infections (adult HIV incidence 0.96%), 691,900 asymptomatic prevalent infections, 88 100 AIDS cases, and 76 400 AIDS deaths. An estimated 647,000 (80%) HIV-infected adults were unaware of their infection; one third of all adult deaths were HIV related. As a result of population growth, by 2008 a similar number of people will be HIV infected (1.1 million) as during the peak of the epidemic in 1994. Although antiretroviral therapy (ART) coverage is expected to rise from 67,000 (2005) to 160,000 (2010), the number of persons needing but not receiving ART will decrease only slightly from 127,600 (2005) to 111,100 (2010). The use of single-dose in 2005 nevirapine probably averted only 4% of the estimated 20 400 vertical infections.

CONCLUSION

HIV/AIDS continues to be a leading cause of adult disease and death in Uganda. Universal ART access is probably unachievable. With the absolute burden of HIV disease approaching the historic peak in the early 1990s, more effective prevention programmes are of paramount importance.

Mortality associated with HIV-1, HIV-2, and HTLV-I single and dual infections in a middle-aged and older population in Guinea-Bissau

BACKGROUND

In Guinea-Bissau HIV-1, HIV-2, and HTLV-I are prevalent in the general population. The natural history of HIV/HTLV-I single and dual infections has not been fully elucidated in this population. Previous studies have shown that combinations of these infections are more common in older women than in men. The present study compares mortality associated with HIV-1, HIV-2, and HTLV-I single and dual infections in individuals over 35 years of age within an urban community-based cohort in Guinea-Bissau.

RESULTS

A total of 2,839 and 1,075 individuals were included in the HIV and HTLV-I mortality analyses respectively. Compared with HIV-negative individuals, adjusted mortality rate ratios (MRRs) were 4.9 (95% confidence interval (CI): 2.3, 10.4) for HIV-1, 1.8 (95%CI: 1.5, 2.3) for HIV-2, and 5.9 (2.4, 14.3) for HIV-1/HIV-2 dual infections. MRR for HTLV-I-positive compared with HTLV-I-negative individuals was 1.7 (1.1, 2.7). Excluding all HIV-positive individuals from the analysis, the HTLV-I MRR was 2.3 (1.3, 3.8). The MRR of HTLV-I/HIV-2 dually infected individuals was 1.7 (0.7, 4.3), compared with HIV/HTLV-I-negative individuals. No statistically significant differences were found in retrovirus-associated mortality between men and women.

CONCLUSION

HIV-1-associated excess mortality was low compared with community studies from other parts of Africa, presumably because this population was older and the introduction of HIV-1 into the community recent. HIV-2 and HTLV-I-associated mortality was 2-fold higher than the mortality in uninfected individuals. We found no significant differences between the mortality risk for HIV-2 and HTLV-I single infection, respectively, and HIV-2/HTLV-I dual infection. The higher prevalence of retroviral dual infections in older women is not explained by differential retrovirus-associated mortality for men and women.

Critique of early models of the demographic impact of HIV/AIDS in sub-Saharan Africa based on contemporary empirical data from Zimbabwe

Early mathematical models varied in their predictions of the impact of HIV/AIDS on population growth from minimal impact to reductions in growth, in pessimistic scenarios, from positive to negative values over a period of 25 years. Models predicting negative rates of natural increase forecast little effect on the dependency ratio. Twenty years later, HIV prevalence in small towns, estates, and rural villages in eastern Zimbabwe, has peaked within the intermediate range predicted by the early models, but the demographic impact has been more acute than was predicted. Despite concurrent declines in fertility, fueled in part by HIV infections (total fertility is now 8% lower than expected without an epidemic), and a doubling of the crude death rate because of HIV/AIDS, the rate of natural population increase between 1998 and 2005 remained positive in each socioeconomic stratum. In the worst-affected areas (towns with HIV prevalence of 33%), HIV/AIDS reduced growth by two-thirds from 2.9% to 1.0%. The dependency ratio fell from 1.21 at the onset of the HIV epidemic to 0.78, the impact of HIV-associated adult mortality being outweighed by fertility decline. With the benefit of hindsight, the more pessimistic early models overestimated the demographic impact of HIV epidemics by overextrapolating initial HIV growth rates or not allowing for heterogeneity in key parameters such as transmissibility and sexual risk behavior. Data collected since the late 1980s show that there was a mismatch between the observed growth in the HIV epidemic and assumptions made about viral transmission.

Population and antenatal-based HIV prevalence estimates in a high contracepting female population in rural South Africa

Background

To present and compare population-based and antenatal-care (ANC) sentinel surveillance HIV prevalence estimates among women in a rural South African population where both provision of ANC services and family planning is prevalent and fertility is declining. With a need, in such settings, to understand how to appropriately adjust ANC sentinel surveillance estimates to represent HIV prevalence in general populations, and with evidence of possible biases inherent to both surveillance systems, we explore differences between the two systems. There is particular emphasis on unrepresentative selection of ANC clinics and unrepresentative testing in the population.

Methods

HIV sero-prevalence amongst blood samples collected from women consenting to test during the 2005 annual longitudinal population-based serological survey was compared to anonymous unlinked HIV sero-prevalence amongst women attending antenatal care (ANC) first visits in six clinics (January to May 2005). Both surveillance systems were conducted as part of the Africa Centre Demographic Information System.

Results

Population-based HIV prevalence estimates for all women (25.2%) and pregnant women (23.7%) were significantly lower than that for ANC attendees (37.7%). A large proportion of women attending urban or peri-urban clinics would be predicted to be resident within rural areas. Although overall estimates remained significantly different, presenting and standardising estimates by age and location (clinic for ANC-based estimates and individual-residence for population-based estimates) made some group-specific estimates from the two surveillance systems more predictive of one another.

Conclusion

It is likely that where ANC coverage and contraceptive use is widespread and fertility is low, population-based surveillance under-estimates HIV prevalence due to unrepresentative testing by age, residence and also probably by HIV status, and that ANC sentinel surveillance over-estimates prevalence due to selection bias in terms of age of sexual debut and contraceptive use. The results presented highlight the importance of accounting for unrepresentative testing, particularly by individual residence and age, through system design and statistical analyses.

Immunisation coverage among children born to HIV-infected women in Rakai district, Uganda: effect of voluntary testing and counselling (VCT)

To evaluate the impact of maternal HIV-infection on routine childhood Immunisation coverage, we compared the Immunisation status of children born to HIV-infected and HIV-uninfected women in rural Uganda. The study population was 214 HIV(+) and 578 HIV(-) women with children aged 6 to 35 months previously enrolled in a community study to evaluate maternal and child health in Rakai District, Uganda. Sampling of subjects for interview was stratified by the use of voluntary counselling and testing (VCT) service so that the final sample was four groups: HIV + /VCT+ (n = 98); HIV + /VCT- (n = 116); HIV - /VCT+ (n= 348); HIV - /VCT- (n = 230). The main outcome measure was the percent of complete routine childhood Immunisations recommended by the WHO as assessed from Immunisation cards or maternal recall during household interviews. We found that Immunisation coverage in the overall sample was 26.1%. For all vaccines, children born to HIV-infected mothers had lower Immunisation coverage than children born to HIV-negative mothers (21.3 vs. 27.7%). There was a statistically significant interaction between maternal HIV-infection and maternal knowledge of HIV-infection (p = 0.034). The children of mothers who were HIV-infected and knew their serostatus (HIV + /VCT + ) had a more than two-fold odds of underImmunisation (OR = 2.21, 95% CI: 1.14, 4.29) compared to children of mothers who were HIV - /VCT-. We conclude that maternal HIV-infection was associated with childhood underImmunisation and this was mediated by a mother's knowledge of her HIV status. HIV VCT programmes should encourage HIV-infected mothers to complete childhood Immunisation. Improving access to Immunisation services could benefit vulnerable populations such as children born to HIV-infected mothers.

Using HIV voluntary counseling and testing data for monitoring the Uganda HIV epidemic, 1992-2000

OBJECTIVE

To assess trends in the prevalence of HIV infection among voluntary counseling and testing (VCT) clients in Uganda and to describe the utility of VCT data for monitoring the HIV epidemic in 1992-2000.

METHODS

We analyzed routinely collected data from first-time VCT clients not reporting illness as a reason for testing. We developed a model adjusting for test site, couple testing, and premarital testing, assessed trends in adjusted prevalence of HIV infection and shifts in age-specific peak prevalence, and compared antenatal clinic (ANC) surveillance data and VCT prevalence trends.

RESULTS

Among 201,741 clients, adjusted prevalence of HIV infection declined from 23% in 1992 to 13% in 2000 (P < 0.001) (men, 17%-9% [P < 0.001]; women, 31%-18% [P < 0.001]). The prevalence declined for all age groups except men older than 39 years and women older than 34 years. The prevalence increased for women older than 39 years (P < 0.003). Between 1992 and 2000, peak prevalence declined for both men (31% to 24%) and women (44% to 41%), whereas the age at which the peak occurred increased for both men (36 to 41 years) and women (31 to 36 years). VCT and ANC prevalence trends were similar.

CONCLUSION

In Uganda, the prevalence of HIV infection among male and female VCT clients declined from 1992 to 2000, similar to ANC surveillance data, but did not decline in older age groups. In regions with well-established VCT programs, VCT data may provide a useful and convenient tool for monitoring the HIV epidemic.

The incidence and prevalence of orphanhood associated with parental HIV infection: a population-based study in Rakai, Uganda

BACKGROUND

There are limited empirical data on the prevalence and incidence of orphanhood due to parental HIV infection.

OBJECTIVE

To assess the prevalence and incidence of orphanhood, and the population attributable fraction (PAF) of incident orphanhood associated with parental HIV infection, in a rural population with a 14.8% adult HIV prevalence.

METHODS

The data are derived from a community cohort in Rakai District, Uganda. Census data were collected on all resident members in 10,657 households, including survival of parents of resident children in 1996/1997. Consenting adults were interviewed, provided blood for HIV testing, and were followed up 10 months later to determine parental death and incident orphanhood. The incidence rate ratio (IRR) of orphanhood associated with parental HIV-infection was estimated by Poisson multivariate regression.

RESULTS

A total of 22,712 children aged 0-14 years were enumerated in 1996/1997. The overall prevalence of orphanhood was higher among children of HIV-infected parents (22.7%) compared with children of uninfected parents, 7.9%. The annual incidence of orphanhood was 8.2% if at least one parent was HIV positive, and 0.5% if both parents were HIV negative (adjusted IRR = 18.93). Older age of children, and older maternal age were significantly associated with an increased risk of orphanhood. The PAF of incident orphanhood due to parental HIV infection was 37.3%, and was highest among younger children (adjusted PAF = 50.6% for 0-4 year olds), and children with younger mothers aged < 25 years (adjusted PAF = 75.7%).

CONCLUSIONS

Parental HIV infection markedly increased the incidence of orphanhood, especially among younger children and the children of younger mothers.

Pregnant or positive: adolescent childbearing and HIV risk in KwaZulu Natal, South Africa

In communities where early age of childbearing is common and HIV prevalence is high, adolescents may place themselves at risk of HIV because positive or ambivalent attitudes towards pregnancy reduce their motivation to abstain from sex, have sex less often or use condoms. In this study, we analyse cross-sectional survey data from KwaZulu Natal, South Africa, to explore whether an association exists between the desire for pregnancy and perceptions of HIV risk among 1,426 adolescents in 110 local communities. Our findings suggest that some adolescents, girls more than boys, were more concerned about a pregnancy if they lived in environments where youth were perceived to be at high risk of HIV infection. The probability that pregnancy was considered a problem by boys was positively correlated with the proportion of adult community members who thought youth were at risk of acquiring HIV, and for girls by the proportion of peers in the community who thought youth were at risk of HIV. We also found that becoming pregnant would be a bigger problem for the African girls than the white and Indian girls. The analysis suggests that for some adolescents, in addition to effects on educational and employment opportunities, the danger of HIV infection is becoming part of the calculus of the desirability of a pregnancy.

Child survival in relation to mother's HIV infection and survival: evidence from a Ugandan cohort study

OBJECTIVE

To analyse the contribution of maternal survival and HIV status to child (under-5 years) mortality in a rural population cohort in South-west Uganda.

METHODS

Approximately 10 000 people residing in 15 neighbouring villages were followed between 1989 and 2000 using annual censuses and serological surveys to collect data on births, deaths, and adult HIV serostatus. Mother-child records were linked, child mortality risks (per 1000 births) and hazard ratios (HRs) for child mortality according to maternal HIV serostatus were computed, allowing for time-varying covariates.

RESULTS

A total of 3727 children were born, of whom 415 died during 14 110 child years of follow-up. Mother's HIV status at birth was ascertained unambiguously for 3004 children, of whom 218 were born to HIV-positive mothers. Infant mortality risk was higher for HIV seropositive than seronegative mothers (225 versus 53) as was child mortality risk (313 versus 114). Child mortality risk was also higher for mothers who died (571) than for surviving mothers (128). After controlling for child's age and sex, independent predictors of mortality in children were: mother's terminal illness or death (HR = 3.8); mother being HIV positive (HR = 3.2); child being a twin (HR = 2.0); teenage motherhood (HR = 1.7) and maternal absence (HR = 1.7).

CONCLUSION

Maternal survival and HIV status are strong predictors of child survival. The higher mortality in HIV-infected women compounds mortality risks for their children, regardless of children's HIV status. Programmes aimed at the welfare of children should take into account the independent effect of mothers' HIV and vital status.

Trends and measurement of HIV prevalence in northern Malawi

BACKGROUND

Most data on HIV prevalence in Malawi come from antenatal clinic (ANC) surveillance and are, therefore, subject to bias.

OBJECTIVES

HIV prevalence and risk factors were measured using population-based data to assess the accuracy of ANC surveillance and changes in prevalence and risk factors for HIV over time.

METHODS

HIV prevalence was measured in 1988-1993 and 1998-2001 in community controls from case-control studies of mycobacterial disease in Karonga District, Malawi. ANC surveillance studies in the district began in 1999.

RESULTS

Age and area-standardized HIV prevalence in women aged 15-49 years in the community was 3.9% in 1988-1990, 12.5% in 1991-1993 and 13.9% in 1998-2001. For men, HIV prevalence was 3.7%, 9.2% and 11.4% in the same periods. In 1988-1993, HIV positivity was associated with occupations other than farming, with increased schooling and being born outside Karonga District. In 1998-2001, non-farmers were still at higher risk but the other associations were not seen. The age- and area-adjusted HIV prevalence in the ANC in 1999-2001 was 9.2%. The underestimate can be explained largely by marriage and mobility. Reduced fertility in HIV-positive individuals was demonstrated in both ANC and community populations. A previously recommended parity-based adjustment gave an estimated female HIV prevalence of 15.0%.

CONCLUSIONS

HIV prevalence has increased and continues to be higher in non-farmers. The increase is particularly marked in those with no education. ANC surveillance underestimated HIV prevalence in the female population in all but the youngest age group. Although there were differences in sociodemographic factors, a parity-based adjustment gave a reasonable estimate of female HIV prevalence.

HIV impact on mother and child mortality in rural Tanzania

Child mortality in Tanzania rose from 137 per 1000 in 1992-1996 to 147 per 1000 in 1995-1999. Impact of HIV on child mortality is analyzed in a longitudinal community-based study in Kisesa ward, Mwanza region. HIV data on 4273 mothers from 3 rounds of serologic testing are linked to survival information for 6049 children born between 1994 and 2001, contributing 10,002 person-years of observation and 584 child deaths. Impacts of maternal survival and HIV status on child mortality are assessed using hazard analysis. Infant mortality for children of HIV-positive mothers was 158 per 1000 live births compared with 79 per 1000 for children of uninfected mothers; by age 5, child mortality risks were 270 per 1000 live births and 135 per 1000, respectively. Fifty-one deaths were observed among child-bearing women, 14 to HIV-positive mothers. Infant mortality among children whose mothers died was 489 per 1000 live births compared with 84 per 1000 for children of surviving mothers. Maternal death effects were statistically independent of HIV status. Allowing for age, sex, twinning, birth interval, maternal education, and residence, the child death hazard ratio for maternal HIV infection was 2.3 (1.7-3.3); hazard ratio associated with maternal death was 4.8 (2.7-8.4). The HIV-attributable fraction of infant mortality is 8.3% in a population in which prevalence among women giving birth is around 6.2%.

HIV and population dynamics: a general model and maximum-likelihood standards for east Africa

In high-prevalence populations, the HIV epidemic undermines the validity of past empirical models and related demographic techniques. A parsimonious model of HIV and population dynamics is presented here and fit to 46,000 observations, gathered from 11 East African populations. The fitted model simulates HIV and population dynamics with standard demographic inputs and only two additional parameters for the onset and scale of the epidemic. The underestimation of the general prevalence of HIV in samples of pregnant women and the fertility impact of HIV are examples of the dynamic interactions that demographic models must reproduce and are shown here to increase over time even with constant prevalence levels. As a result, the impact of HIV on population growth appears to have been underestimated by current population projections that ignore this dynamic.

The long-term impact of HIV and orphanhood on the mortality and physical well-being of children in rural Malawi

OBJECTIVE

To assess the influence of maternal HIV status and orphanhood on child mortality and physical well-being.

DESIGN

Retrospective cohort study with > 10 years of follow-up.

METHODS

From population-based surveys in Karonga District, Malawi in the 1980s, 197 individuals were identified as HIV-positive. These individuals and 396 HIV-negative individuals matched for age and sex, and their spouses and offspring, were sought in 1998-2000.

RESULTS

All but 11 of the index individuals were traced, identifying 2520 offspring; of these, 1106 offspring were included in analyses. Among those with HIV-positive mothers, mortality was 27% [95% confidence interval (CI), 17-38] in infants (1-30 days), 46% (95% CI, 34-58) in those under 5 years and 49% (95% CI, 38-61) in those under 10 years. The corresponding figures for those with HIV-negative mothers were 11% (95% CI, 8-13), 16% (95% CI, 13-19) and 17% (95% CI, 14-20). Death of HIV-positive mothers, but not of HIV-negative mothers or of fathers, was associated with increased child mortality. Among survivors who were still resident in the district, neither maternal HIV status nor orphanhood was associated with stunting, being wasted, or reported ill-health.

CONCLUSIONS

Mortality in children under 5 years is much higher in children born to HIV-positive mothers than in those born to HIV-negative mothers. With 10% of pregnant women HIV-positive, we estimate that approximately 18% of under-5 deaths in this population are attributable to HIV. Most of the excess is attributable to vertical transmission of HIV. Our findings suggest that, in terms of physical well-being, the extended family in this society has not discriminated against surviving children whose parents have been ill or have died as a result of HIV/AIDS.

Mothers infected with HIV

The HIV/AIDS epidemic intersects with the problem of maternal mortality in many circumstances. The extent of the contribution of HIV/AIDS to maternal mortality is difficult to quantify, as the HIV status of pregnant women is not always known. HIV infection and AIDS-related deaths have become one of the major causes of maternal mortality in many resource-poor settings. HIV impacts on direct (obstetrical) causes of maternal mortality by an associated increase in pregnancy complications such as anaemia, post-partum haemorrhage and puerperal sepsis. HIV is also a major indirect cause of maternal mortality by an increased susceptibility to opportunistic infections such as Pneumocystis carinii pneumonia, tuberculosis and malaria. Appropriate antiretroviral therapy started in pregnancy could reverse the toll of HIV-related maternal mortality. Without such efforts and increased HIV prevention, the gains achieved by safe motherhood programmes will be lost in the future.

Mortality of HIV-1, HIV-2 and HIV-1/HIV-2 dually infected patients in a clinic-based cohort in The Gambia

OBJECTIVE

To assess and compare the mortality rates of patients with HIV-1, HIV-2 or both infections (HIV-D) in the same population.

DESIGN

Clinic-based cohort study.

METHODS

HIV-seropositive patients aged 15 years and older who attended the Medical Research Council clinics in Fajara between May 1986 and September 1997 were recruited. Clinical assessment using the Karnofsky score, CDC cell staging, WHO staging, and CD4 cell counts was performed at baseline. Patients attended clinic every 3 months; if they did not attend, they were visited at home by field workers to ascertain survival status. No patient was on antiretroviral therapy during the study period.

RESULTS

Data from 1519 HIV-positive adult patients were analysed. A total of 746 patients had HIV-1, 666 HIV-2, and 107 patients had HIV-D. A total of 828 patients (55%) died, and 161 (11%) were lost to follow-up. The median follow-up was 12 months (range 0-128). CD4 cell counts were available for 894 patients. Compared with HIV-1, the adjusted hazards ratio for mortality in the CD4 cell count category 500 cells/microl or greater was 0.50 for HIV-2 (95% CI 0.28-0.88) and 1.27 (95% CI 0.51-3.7) for HIV-D. Among those with CD4 cell counts less than 500 cells/microl the mortality rates in HIV-2 and HIV-D were similar to those in HIV-1.

DISCUSSION

HIV-2-infected patients with CD4 cell counts of 500 cells/microl and greater had a significantly lower mortality rate than HIV-1-infected patients. HIV-2-infected patients with advanced disease had the same poor prognosis as patients with HIV-1. Dually infected patients had mortality rates similar to HIV-1.

Long-term follow-up of HIV-positive and HIV-negative individuals in rural Malawi

OBJECTIVE

To measure the effect of HIV on survival in rural Africa.

DESIGN

A retrospective cohort study with more than 10 years follow-up.

METHODS

Individuals with known HIV status in the 1980s were identified from previous population surveys in Karonga District, northern Malawi. Follow-up studies were conducted in 1998-2000 to trace 197 HIV-positive and 396 age-sex-matched HIV-negative individuals and their spouses.

RESULTS

Information was obtained on all but 11 index individuals. Half (302) were found and the others were reported to have died (161) or to be alive outside the district (119). Ten year survival was 36% in the HIV-positive cohort and 90% in the initially HIV-negative cohort. The death rate was 93.3 per 1000 person-years in the HIV-positive individuals, and 11.3 in the initially HIV-negative individuals. Survival time since the initial test in HIV-positive individuals decreased with age, but relative survival, compared with HIV-negative individuals, was similar across age groups. The effect of HIV on survival was similar in men and women. Spouses of HIV-positive individuals had four times the mortality rate, and among survivors, four times the HIV prevalence, of spouses of initially HIV-negative individuals.

CONCLUSION

HIV-infected individuals had very high mortality rates, but one-third were still alive at 10 years. This is consistent with median survival from seroconversion being similar to that found in developed countries before antiretroviral therapy. Mortality rates in HIV-positive individuals increased with age, but relative mortality changed little with age.

The impact of HIV/AIDS on mortality and household mobility in rural Tanzania

OBJECTIVE

To assess the impact of the AIDS epidemic on mortality and household mobility before and after death.

DESIGN

Open community cohort study with a demographic surveillance system and two sero-epidemiological surveys.

METHODS

Ten rounds of demographic surveillance were completed during 1994-1998 in the study area, which has a population of about 20 000 people in a rural ward in north-west Tanzania. Households with deaths were visited for a detailed interview, including a verbal autopsy. Data on HIV status were collected in two surveys of all residents aged 15-44 years.

RESULTS

Mortality rates among HIV-infected adults were 15 times higher than those among HIV-negative adults and HIV/AIDS was associated with nearly half of deaths at ages 15-44 years. Verbal autopsies without HIV test results considerably underestimated the proportion of deaths associated with HIV/AIDS. The mortality probability between 15 and 60 years was 49% for men and 46% for women and life expectancy was 43 years for men and 44 years for women. By their second birthday nearly one-quarter of the newborns of HIV-infected mothers had died, which was 2.5 times higher than among children of HIV-negative mothers. Mobility of household members before and after death was high. In 44% of households in which the head died all members moved out of the household.

CONCLUSIONS

In this rural population with HIV prevalence close to 7% among adults aged 15-44 years during the mid-1990s, HIV/AIDS is having substantial impact on adult mortality. A common response to death of a head of household in this community is household dissolution, which has implications for measurement of the demographic and socio-economic impact of AIDS.

Pregnancy and infection with human immunodeficiency virus

During the past decade, there has been a dramatic increase in the number of women infected with HIV and the number of women with clinical AIDS. One of the most prominent features of HIV infection is that it is usually diagnosed during the peak reproductive years, and in 1998, HIV/AIDS was the fourth leading cause of death among women between the ages of 25 and 44 years. For this reason, there has been long-standing concern regarding the obstetric implications of HIV infection: both the impact of pregnancy on possibly accelerating the course of HIV disease and the impact of HIV infection on the course of pregnancy. There appears to be some immunologic changes associated with pregnancy, but they are not dramatic, and immune markers generally resume their prepregnancy values after delivery. With regard to long-term effects of pregnancy on HIV disease progression, no study to date has shown significant increases in mortality or in AIDS incidence associated with pregnancy. Studies have generally been small, however, and none have accounted for antiretroviral therapy usage. Many studies have shown that certain adverse outcomes are more common in HIV-positive pregnant women as compared with HIV-negative pregnant women, and concerns have been raised that spontaneous abortions may be more common among HIV-infected women and that this may impact fertility rates. Although important understanding has been acquired regarding the associations between pregnancy and the course of HIV infection, much remains to be understood. Additional, well-designed studies are clearly needed to rigorously address the many remaining questions that exist. We can anticipate that the resolution of these questions will continue to be of broad public health interest as the epidemic impacts increasing numbers of women, a large fraction of whom will be adolescents.

Mathematical models of the transmission and control of sexually transmitted diseases

BACKGROUND

The development of mathematical models to describe and interpret the epidemiology of sexually transmitted infections has involved the incremental addition of various forms of biological and behavioral complexity to simple mathematical templates.

GOAL

To review simple and complex models used in study of observed epidemiologic pattern.

STUDY DESIGN

An overview of modeling in sexually transmitted disease epidemiology identifies the function of different types of models.

RESULTS

Simple models have the advantage of transparency and analytical tractability and can illustrate the relative merits of different intervention options. However, real life is replete with complexities that can have effects that are difficult to predict in the absence of a mathematical framework.

CONCLUSIONS

Research should increasingly be based on robust parameterization of model structures and try to capture individual behaviors. Progress will be most rapid by interdisciplinary work where the clinician, epidemiologist, and mathematician work collaboratively to help improve our knowledge of how to best control infection and disease.

Mortality associated with HIV infection in rural Rakai District, Uganda

OBJECTIVE

To assess mortality impact of HIV in rural Uganda.

METHODS

An open cohort of 19983 adults aged 15-59 years, in Rakai district was followed at 10 month intervals for four surveys. Sociodemographic characteristics and symptomatology/disease conditions were assessed by interview. Deaths among residents and out-migrants were identified household census. Mortality rates were computed per 1000 person years (py) and the rate ratio (RR) of death in HIV-positive/HIV-negative subjects, and the population attributable fraction (PAF) of death were estimated according to sociodemographic characteristics. Mortality associated with potential AIDS defining symptoms and signs was assessed.

RESULTS

HIV prevalence was 16.1%. Mortality was 132.6 per 1000 py in HIV-infected versus 6.7 per 1000 py in uninfected subjects, and 73.5% of adult deaths were attributable to HIV infection. Mortality increased with age, but the highest attributable risk of HIV associated deaths were observed in persons aged 20-39 years (PAF > 80%) and in women. HIV associated mortality was highest in the better educated (PAF > or = 75%) and among government employees (PAF > or = 82%). Of the HIV-positive subjects 40.5% reported no illness < 10 months preceding death, symptoms were poor predictors of death (sensitivity 1.6-38.8%), and only 9.1% met the World Health Organization clinical definition of AIDS. Infant mortality rates in babies of HIV-infected and uninfected mothers were 209.4 and 97.7 per 1000, respectively.

CONCLUSION

HIV is taking substantial toll in this population, particularly among the younger better educated adults, and infants. Symptomatology or the World Health Organization definition of AIDS are poor predictors of death.

Uncertainties in predicting the demographic impact of AIDS

A model giving the demographic impact of AIDS is analysed to examine the sensitivity of the projections when various complicating features are included. The model deals with age and sexual partner change rate as continuous variables and uses a device to specify arbitrary correlations between the ages of the people who form sexual partnerships. The device ensures consistency, in that the amount of partner formation is the same regardless of whether the partnerships are counted from the point of view of males or females. Arbitrary correlation between partner change rate and fertility is also permitted. The results show the uncertainty in model predictions that population growth will reduce over the next 20 years to approximately zero in parts of East Africa severely affected by the AIDS epidemic. The main sources of uncertainty in the model predictions are assumptions concerning the correlation between ages in a partnership, the correlation between partner change rate and fertility, the incubation period of AIDS, and the variability of the female partner change rate.

Autopsy study of HIV-1-positive and HIV-1-negative adult medical patients in Nairobi, Kenya

HIV infection has now been consistently identified as the major cause of death in young Africans in both urban and rural areas. In Africa, several studies have defined the clinical presentation of HIV disease but there have only been a limited number of autopsy studies. Because of the scarcity of autopsy data and the possibility of differing type and frequency of opportunistic infections between different geographic locations we set out to study consecutive new adult medical admissions to a tertiary referral hospital in Nairobi and perform autopsies on a sample of HIV-1-positive and HIV-1-negative patients who died in the hospital ward. Basic demographic data were collected on all patients admitted to two acute medical wards over an 11-month period. Final outcome and final clinical diagnoses were recorded at discharge or death. An autopsy examination was requested if the patient died in the ward. Autopsy examination was performed in 75 HIV-1-positive (40 men, 35 women) and 47 HIV-1-negative (28 men, 19 women) adults who died in the hospital. This represented 48.4% of all HIV-1-positive deaths and 33.3% of all HIV-1-negative deaths. Tuberculosis (TB) and bacterial and interstitial bronchopneumonia accounted for 96% of the major pathology in patients found to be HIV-1-positive at autopsy. TB was present in half the HIV-1-positive autopsy patients and was disseminated in over 80% of cases. Meningeal involvement was present in 26% of those with disseminated TB. By contrast, TB was much less common in the HIV-1-negative patients at autopsy in whom bacterial bronchopneumonia and malignancies were the most common pathologies. The type pathology found in the HIV-1-positive autopsy patients was not different than that found in other areas in Africa so far studied.

HIV incidence and HIV-associated mortality in a cohort of factory workers and their spouses in Tanzania, 1991 through 1996

OBJECTIVE

To describe HIV incidence and HIV-associated mortality in a cohort of factory workers and their spouses with access to adequate sexually transmitted diseases (STD) treatment services and moderate exposure to sexual health interventions.

METHODS

Follow-up visits at 4-month intervals and home follow-up of those who failed to keep appointments were used to estimate HIV incidence and mortality in a cohort of factory workers and their spouses in Mwanza, Tanzania, during 1991 to 1996.

RESULTS

HIV prevalence at intake was 10.5% and 15.3% among 1,594 men and 880 women, respectively. HIV incidence was just over 1/100 person-years (PY) in 1,427 men and 1.9/100 PY in 745 women. The main risk factors were related to sexual behavior and clinical evidence of an STD, although only one seventh of those with HIV seroconversions had had an STD during the period following the second-from-last follow-up visit. HIV incidence among discordant couples was 5.0 and 8.3/100 PY for 41 men and 37 women, respectively. Mortality rates were 9.0 and 7.8/1,000 PY for men and women, respectively, and 65% of male and 60% of female deaths were attributable to HIV infection.

CONCLUSIONS

In this factory population with good access to and use of STD treatment and with a moderate level of exposure to HIV prevention education, HIV incidence among men and women is still over 1/100 PY, which suggests a relatively high level of program effort is needed to lower incidence. More than half of all adult deaths were attributable to HIV, but greater increases in HIV-associated mortality are likely.