Maternal systemic or cord blood inflammation is associated with birth anthropometry in a Tanzanian prospective cohort.

OBJECTIVES: HIV infection is associated with chronic systemic inflammation, with or without antiretroviral therapy. Consequences for foetal growth are not understood, particularly in settings where multiple maternal infections and malnutrition are common. The study was designed to examine maternal systemic circulating and umbilical cord blood cytokine concentrations in relation to birth anthropometry in a Tanzanian prospective cohort. METHODS: A 9-plex panel of maternal plasma cytokines in HIV-positive (n = 44) and HIV-negative (n = 70) mothers and the same cytokines in umbilical cord blood collected at delivery was assayed. Linear regression modelled associations between maternal or cord blood cytokines and birth anthropometry. RESULTS: Health indicators (haemoglobin, mid-upper-arm circumference, body mass index) in HIV-positive mothers without considerable immunosuppression did not differ from HIV-negative women. Despite this, HIV-exposed infants had lower birthweight and length. Subgroup analyses indicated that HIV management using HAART was associated with lower plasma TNF-α, as were longer durations of any antiretroviral therapy (≥2 months). Greater maternal plasma TNF-α was associated with earlier delivery (-1.7 weeks, P = 0.039) and lower birthweights (-287 g; P = 0.020), while greater umbilical cord TNF-α (-1.43 cm; P = 0.036) and IL-12p70 (-2.4 cm; P = 0.008) were associated with shorter birth length. Birthweight was inversely associated with cord IL-12p70 (-723 g; P = 0.001) and IFN-γ (-482 g, P = 0.007). Maternal cytokines during pregnancy did not correlate with umbilical cord cytokines at delivery. CONCLUSIONS: Systemic inflammation identified in maternal plasma or umbilical cord blood was associated with poorer birth anthropometrics in HIV-exposed and HIV-unexposed infants. Controlling maternal and/or foetal systemic inflammation may improve birth anthropometry.

Low mortality risk but high loss to follow-up among patients in the Tanzanian national HIV care and treatment programme.

UNLABELLED: OBJECTIVE To analyse survival and retention rates of the Tanzanian care and treatment programme. METHODS: Routine patient-level data were available from 101 of 909 clinics. Kaplan-Meier probabilities of mortality and attrition after ART initiation were calculated. Mortality risks were corrected for biases from loss to follow-up using Egger's nomogram. Smoothed hazard rates showed mortality and attrition peaks. Cox regression identified factors associated with death and attrition. Median CD4 counts were calculated at 6 month intervals. RESULTS: In 88,875 adults, 18% were lost to follow up 12 months after treatment initiation, and 36% after 36 months. Cumulative mortality reached 10% by 12 months (15% after correcting for loss to follow-up) and 14% by 36 months. Mortality and attrition rates both peaked within the first six months, and were higher among males, those under 45 kg and those with CD4 counts below 50 cells/µl at ART initiation. In the first year on ART, median CD4 count increased by 126 cells/µl, with similar changes in both sexes. CONCLUSION: Earlier diagnoses through expanded HIV testing may reduce high mortality and attrition rates if combined with better patient tracing systems. Further research is needed to explore reasons for attrition.

The impact of mobility on HIV control: a modelling study.

Mobility is associated with HIV due to more risky sexual behaviour of mobile groups such as travellers and migrants. Limited participation of such groups may reduce the effectiveness of HIV interventions disproportionally. The established STDSIM model, which simulates transmission and control of HIV and STD, was extended to simulate mobility patterns based on data from Tanzania. We explored the impact of non-participation of mobile groups (travellers and recent migrants) on the effectiveness of two interventions: condom promotion and health education aiming at partner reduction. If mobile groups do not participate, the effectiveness of both interventions could be reduced by 40%. The impact of targeting travellers with a combined HIV campaign is close to that of a general population intervention. In conclusion, it is important to account for possible non-participation of migrants and travellers. If non-participation is substantial, impact of interventions can be greatly improved by actively approaching these people.

Verbal autopsy can consistently measure AIDS mortality: a validation study in Tanzania and Zimbabwe.

BACKGROUND: Verbal autopsy is currently the only option for obtaining cause of death information in most populations with a widespread HIV/AIDS epidemic. METHODS: With the use of a data-driven algorithm, a set of criteria for classifying AIDS mortality was trained. Data from two longitudinal community studies in Tanzania and Zimbabwe were used, both of which have collected information on the HIV status of the population over a prolonged period and maintained a demographic surveillance system that collects information on cause of death through verbal autopsy. The algorithm was then tested in different times (two phases of the Zimbabwe study) and different places (Tanzania and Zimbabwe). RESULTS: The trained algorithm, including nine signs and symptoms, performed consistently based on sensitivity and specificity on verbal autopsy data for deaths in 15-44-year-olds from Zimbabwe phase I (sensitivity 79%; specificity 79%), phase II (sensitivity 83%; specificity 75%) and Tanzania (sensitivity 75%; specificity 74%) studies. The sensitivity dropped markedly for classifying deaths in 45-59-year-olds. CONCLUSIONS: Verbal autopsy can consistently measure AIDS mortality with a set of nine criteria. Surveillance should focus on deaths that occur in the 15-44-year age group for which the method performs reliably. Addition of a handful of questions related to opportunistic infections would enable other widely used verbal autopsy tools to apply this validated method in areas for which HIV testing and hospital records are unavailable or incomplete.

Influence of timing of sexual debut and first marriage on sexual behaviour in later life: findings from four survey rounds in the Kisesa cohort in northern Tanzania.

OBJECTIVES: To evaluate quality of sexual debut and first marriage data, measure trends and study the association of risky sexual behaviour in youth with adult risk behaviour. METHODS: Reports on age at first sex (AFS) and age at first marriage (AFM) from the Kisesa cohort study, 1994-2004, were evaluated for consistency and used to describe trends in median age-at-event and time spent single but sexually active in different birth cohorts. The association of these variables with marital stability and numbers of partners at later ages was explored using statistical regression techniques. RESULTS: AFS and AFM were inconsistently reported by 32% and 33% of respondents, respectively, but there was no general tendency to report lower or higher ages at a later report date. In 10-year birth cohorts born between 1950-9 and 1980-9, male median AFS declined from 18.1 to 17.0 years and female median AFM rose from 16.2 to 16.6 years. Young people of both sexes currently spend longer sexually active but unmarried than previously. Early marriage is statistically associated with remarriage and polygamy; longer time between sexual debut and marriage is associated with higher numbers of partners at later stages of life. CONCLUSION: Inconsistent reporting of age-at-event introduces noise but does not bias estimates of population level indicators. Lengthening time spent single and sexually active suggests that men and women entering first marriage will have been exposed to increased numbers of non-marital partners. Successful youth interventions may also influence adult behaviour.

Scaling up stigma? The effects of antiretroviral roll-out on stigma and HIV testing. Early evidence from rural Tanzania.

OBJECTIVE: To investigate the interplay between antiretroviral therapy (ART) scale-up, different types of stigma and Voluntary Counselling and Testing (VCT) uptake 2 years after the introduction of free ART in a rural ward of Tanzania. METHODS: Qualitative study using in-depth interviews and group activities with a purposive sample of 91 community leaders, 77 ART clients and 16 health providers. Data were analysed for recurrent themes using NVIVO-7 software. RESULTS: The complex interplay between ART, stigma and VCT in this setting is characterised by two powerful but opposing dynamics. The availability of effective treatment has transformed HIV into a manageable condition which is contributing to a reduction in self-stigma and is stimulating VCT uptake. However, this is counterbalanced by the persistence of blaming attitudes and emergence of new sources of stigma associated with ART provision. The general perception among community leaders was that as ART users regained health, they increasingly engaged in sexual relations and "spread the disease." Fears were exacerbated because they were perceived to be very mobile and difficult to identify physically. Some leaders suggested giving ART recipients drugs "for impotence," marking them "with a sign" and putting them "in isolation camps." In this context, traditional beliefs about disease aetiology provided a less stigmatised explanation for HIV symptoms contributing to a situation of collective denial. CONCLUSION: Where anticipated stigma prevails, provision of antiretroviral drugs alone is unlikely to have sufficient impact on VCT uptake. Achieving widespread public health benefits of ART roll-out requires community-level interventions to ensure local acceptability of antiretroviral drugs.

The "seeded" focus group: a strategy to recruit HIV+ community members into treatment research.

OBJECTIVE(S): We piloted an innovative community-based recruitment approach to contact known HIV+ individuals for referral to treatment without endangering their confidentiality. METHODS: Nested within an HIV cohort study, operations research to monitor and improve rural uptake of antiretroviral therapy (ART) was conducted alongside the introduction of Tanzania's national treatment programme. We confronted the challenge of recruiting participants without inadvertently disclosing their HIV status to family or other community members. During post-test counselling, nurses compiled a list of HIV+ persons who expressed interest in being contacted when ART became available. Study numbers, but not names, of 12 "seeds" were added to a randomly generated list of residents, matched by age group and sex, and all were invited to participate in focus-group discussions on community perceptions of treatment. After the discussion, the original counsellors met each participant in private, inviting the "seed" for ART referral and offering VCT to others. RESULTS: Ten "seeds" were successfully located and attended the local focus-group discussion; all subsequently volunteered to undergo clinical tests in advance of receiving antiretroviral therapy. They also agreed to participate in a study of barriers to ART access. The other focus-group members contributed useful information on levels of understanding and support for treatment, and several came forward for HIV testing. CONCLUSIONS: The "seeded" focus group is a very straightforward and easily arranged method of recruiting HIV+ people for research or service delivery within a wider context of engaging with local community perceptions.

HIV prevalence and sexual behaviour changes measured in an antenatal clinic setting in northern Tanzania.

OBJECTIVES: To assess the feasibility of collecting sexual behaviour data during HIV surveillance in antenatal care (ANC) clinics, and to establish whether these data can provide information about the correlates of HIV infection in this population. METHODS: Sexual behaviour surveys were conducted in the context of two HIV sentinel surveillance rounds in 11 ANC clinics in north west Tanzania between 2000 and 2002. Responses of individual women were anonymously linked to their HIV status. Three clinic catchment areas overlapped with a community based longitudinal study, which provided independent estimates of HIV prevalence and sexual behaviour. Changes between rounds and differentials between clinics were assessed and a two level logistic regression model used to identify behavioural and contextual correlates of HIV in 3689 women under 25 years of age. RESULTS: Women attending clinics were willing to participate in the study. The sexual behaviour data obtained were internally consistent and tallied reasonably well with sexual behaviour data collected in the community overlapping the clinic catchment. Clear relations emerged between HIV infection and measures of sexual exposure: OR 1.20 (95% CL 1.12 to 1.28) for each year of premarital exposure and 1.09 (1.04 to 1.16) for each year after first marriage; background prevalence OR 1.15 (1.04 to 1.26) associated with each percentage point increase in background prevalence at the clinic; and certain partnership variables such as partner's age OR 0.58 (0.45 to 0.76) if partner less than 10 years older. CONCLUSION: Conducting sexual behaviour surveys in the context of ANC clinics surveillance is feasible and yields useful data.

Community effects on the risk of HIV infection in rural Tanzania.

OBJECTIVES: To investigate the effect of community characteristics on HIV prevalence and incidence. METHODS: Data from an open cohort study with demographic surveillance, epidemiological surveys, and qualitative research were used to examine the association between individual and community risk factors with HIV prevalence in 1994-5 and incidence between 1994-5 and 1996-7 among men (n=2271) and women (n=2752) living in a rural area in northwest Tanzania. Using subvillages as the unit of analysis, community factors investigated were level of social and economic activity, ratio of bar workers per male population aged 18-59, level of community mobility, and distance to the nearest town. Logistic and Cox regression models were estimated to assess community effects, controlling for multiple individual factors. RESULTS: All four community factors had strong effects on HIV transmission. Men who lived in subvillages with the highest level of social and economic activity had an odds of being HIV positive that was about five times higher (OR=4.71, 95% CI=2.89 to 6.71) than those in places with low levels of activity; women in these subvillages had an odds that was twice as high (OR=1.92, 95% CI=1.27 to 2.92). After controlling for community effects, the effects of some individual factors on the risk of HIV-education, male circumcision, type of work, and number of household assets-changed notably. The association between HIV incidence and community factors was in the expected direction, but did not reach statistical significance (RR=2.07, p=0.10). CONCLUSIONS: Results suggest that community characteristics play an important part in the spread of HIV in rural Tanzania. Community effects need both to be considered in individual risk factor analyses and be given more attention in intervention programmes.

Sociodemographic context of the AIDS epidemic in a rural area in Tanzania with a focus on people's mobility and marriage.

This analysis focuses on how sociocultural and economic characteristics of a poor semi-urban and rural population (Kisesa ward) in north west Tanzania may directly and indirectly affect the epidemiology of HIV and other sexually transmitted infections (STI). Poverty and sociocultural changes may contribute to the observed high levels of marital instability and high levels of short and long term migration in Kisesa, especially among younger adults. Marriage and migration patterns are important underlying factors affecting the spread of HIV. The most cost-effective intervention strategy may be to focus on the trading centre in which mobility is higher, bars were more common, and HIV prevalence and incidence were considerably higher than in the nearby rural villages. If resources suffice, additional work can be undertaken in the rural villages, although it is not clear to what extent the rural epidemic would be self sustaining if the interventions in the trading centre were effective.

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.

Dynamics of male circumcision practices in northwest Tanzania.

BACKGROUND: Male circumcision status is considered an important cofactor in the spread of HIV and sexually transmitted disease. There is limited evidence that male circumcision practices in Africa may be changing. GOAL: To assess the determinants of male circumcision status in a traditionally noncircumcising ethnic group and to investigate the reasons for increasing acceptance of circumcision. METHODS: Data from a factory workers study and a rural cohort study in northwest Tanzania were used to analyze the levels and determinants of male circumcision status and assess the reliability of self-reported data. Qualitative data from focus group discussions and in-depth interviews were obtained to ascertain norms and values in relation to male circumcision. RESULTS: Male circumcision has become more popular in recent years, and 21% of 3,491 men reported themselves as circumcised. An increase in circumcision rates was observed in the rural cohort study during 1994 to 1997, though reporting inconsistencies are common. Circumcision rates were higher among men with higher levels of education and in Muslim men. Men are often circumcised in their late teens or twenties. The reasons for the increasing popularity of circumcision were investigated in group discussions and in-depth interviews. The most frequently mentioned reason was health-related; circumcision was thought to enhance penile hygiene, reduce sexually transmitted disease incidence, and improve sexually transmitted disease cure rates. CONCLUSION: Male circumcision is becoming more popular among a traditionally noncircumcising ethnic group in Tanzania, especially in urban areas and among boys who have attended secondary schools.

Pre-marital sexual behaviour among out-of-school adolescents: motives, patterns and meaning attributed to sexual partnership in rural Tanzania.

This paper presents data from a qualitative study on pre-marital sexual behaviours among out-of-school adolescents residing in rural communities from farming and lakeshore settings in Magu District, Northwestern Tanzania. The study found that large numbers of out-of-school adolescents are sexually experienced, that the period from acquaintance or dating to sexual relations is typically short, and that sexual encounters are typically risky. The exchange of money and gifts for sex was reported by both female and male adolescents but perception and interpretation differed widely. Males perceived that females engage in sex largely for material gain while the females saw it as a display, or a partner's love or commitment. These findings call for interventions to empower sexual negotiation skills among adolescents, promote condom use, and at the same time redress gender disparities in expectations and interpretations of sexual relationships.

Adjusting ante-natal clinic data for improved estimates of HIV prevalence among women in sub-Saharan Africa.

OBJECTIVES: To find a simple and robust method for adjusting ante-natal clinic data on HIV prevalence to represent prevalence in the general female population in the same age range, allowing for fertility differences by HIV status. BACKGROUND: HIV prevalence comparisons for pregnant women and women in the general community show that prevalence in the latter is significantly higher than in the former. An adjustment procedure is needed that is specific for the demographic and epidemiological circumstances of a particular population, making maximum use of data that can easily be collected in ante-natal clinics or are widely available from secondary sources. METHODS: Birth interval length data are used to allow for subfertility among HIV-positive women. To allow for infertility, relative HIV prevalence ratios for fertile and infertile women obtained in community surveys in populations with similar levels of contraception use are applied to demographic survey data that describe the structure of the population not at risk of child-bearing. RESULTS: For populations with low contraception use, the procedure yields estimates of general female HIV prevalence of 35-65% higher than the observed ante-natal prevalence, depending on population structure. Results were verified using general population prevalence data collected in Kisesa (Tanzania) and Masaka (Uganda). For high contraception use populations, adjusted values range from 15% higher to 5% lower, but only limited verification has been possible so far. CONCLUSIONS: The procedure is suitable for estimating general female HIV prevalence in low contraception use populations, but the high contraception variant needs further testing before it can be applied widely.

Spread of HIV infection in a rural area of Tanzania.

OBJECTIVE: To assess the spread of HIV into rural areas. METHODS: Since 1994 a demographic surveillance system (with 5-monthly rounds) and open adult cohort study have been established in a rural ward in Tanzania. Two sero-surveys of all resident adults aged 15-44 and 15-46 years were conducted in 1994 1995 and 1996-1997 respectively. Qualitative data were collected on mobility, bars and commercial sex. RESULTS: Attendance of the two rounds of survey was 5820 (78%) and 6413 (80%) in 1994/1995 and 1996/1997 respectively. HIV prevalence increased from 5.8% to 6.6%. HIV incidence was 0.73 and 0.84 per 100 person years among men and women respectively. HIV incidence under the age of 20 years was low among both sexes. Striking differences in HIV prevalence and incidence were observed within the small geographic area studied: HIV prevalence in the trading center was twice that in the area surrounding the trading center (within 2 km) and three to four times that in the rural villages (within 8 km of the trading center). Aggregate level data showed significant differences between the trading center and nearby rural villages in terms of sexual behavior, commercial sex workers, mobility of the population, and alcohol use. CONCLUSION: This study documents the existence of very substantial HIV prevalence and incidence differences within a small geographic rural area. The rapid decrease in HIV prevalence within a small rural area emphasizes the importance of concentrating HIV prevention efforts on high transmission areas, such as trading centers, especially in resource-poor settings. Furthermore, this has considerable implications for monitoring the spread of HIV through sentinel sites, as such sites are typically located in high transmission areas.

Male circumcision and susceptibility to HIV infection among men in Tanzania.

BACKGROUND: Evidence from ecological studies and from studies of and sexually transmitted disease (STD) patients in sub-Saharan Africa suggests that there is a protective effect of male circumcision against HIV infection. There are, however, few population-based studies that have controlled adequately for potential confounding factors. METHODS: Data from the five population-based studies in north-western Tanzania were used to investigate the association between male circumcision and the risk of HIV infection and STD. The effects of circumcision on HIV prevalence, syphilis (positive Treponema pallidum haemagglutination; TPHA) and self-reported STD were analysed, controlling for a range of demographic and sociocultural variables, and indicators of sexual behaviour. RESULTS: In north-western Tanzania, circumcision was previously restricted to Muslims and specific ethnic groups, but is now more widespread, particularly in urban ares and among more educated men. Assessment of the reliability and validity of self-reported circumcision status showed that these data could be considered fairly accurate, although there was some tendency for circumcision to be over-reported. On univariate analysis, circumcision status was unrelated to HIV prevalence in most studies. After controlling for confounding variables, however, there was a modest but significant reduction of the HIV prevalence among circumcised men [odds ratio (OR), 0.62; 95% confidence interval (CI), 0.48-.81]. This effect appeared stronger in urban areas (OR, 0.46; 95% CI, 0.32-0.68) and roadside villages (OR, 0.65; 95% CI, 0.42-1.01) than in rural areas and islands (OR, 1.00 and 1.01 respectively). There was no association between circumcision status and syphilis serology (TPHA), but there was a positive association between circumcision and self-reported STD, although this was not significant after adjustment for confounding variables. CONCLUSION: Male circumcision has a protective effect against HIV infection in this population, which may be stronger in urban areas and roadside settlements than in the rural areas. Ethnic group and religious denomination are no longer the sole determinants of male circumcision.

Male circumcision and susceptibility to HIV infection among men in Tanzania.

BACKGROUND: Evidence from ecological studies and from studies of and sexually transmitted disease (STD) patients in sub-Saharan Africa suggests that there is a protective effect of male circumcision against HIV infection. There are, however, few population-based studies that have controlled adequately for potential confounding factors. METHODS: Data from five population-based studies in north-western Tanzania were used to investigate the association between male circumcision and the risk of HIV infection and STD. The effects of circumcision on HIV prevalence, syphilis (positive Treponema pallidum haemagglutination; TPHA) and self-reported STD were analysed, controlling for a range of demographic and sociocultural variables, and indicators of sexual behaviour. RESULTS: In north-western Tanzania, circumcision was previously restricted to Muslims and specific ethnic groups, but is now more widespread, particularly in urban areas and among more educated men. Assessment of the reliability and validity of self-reported circumcision status showed that these data could be considered fairly accurate, although there was some tendency for circumcision to be over-reported. On univariate analysis, circumcision status was unrelated to HIV prevalence in most studies. After controlling for confounding variables, however, there was a modest but significant reduction of the HIV prevalence among circumcised men [odds ratio (OR), 0.62; 95% confidence interval (CI), 0.48-0.81]. This effect appeared stronger in urban areas (OR, 0.46; 95% CI, 0.32-0.68) and roadside villages (OR, 0.65; 95% CI, 0.42-1.01) than in rural areas and islands (OR, 1.00 and 1.01 respectively). There was no association between circumcision status and syphilis serology (TPHA), but there was a positive association between circumcision and self-reported STD, although this was not significant after adjustment for confounding variables. CONCLUSION: Male circumcision has a protective effect against HIV infection in this population, which may be stronger in urban areas and roadside settlements than in the rural areas. Ethnic group and religious denomination are no longer the sole determinants of male circumcision.