High potential of escalating HIV transmission in a low prevalence setting in rural Tanzania

Association between Taenia solium infection and HIV/AIDS in northern Tanzania: a matched cross sectional-study

BACKGROUND

The frequency of Taenia solium, a zoonotic helminth, is increasing in many countries of sub-Saharan Africa, where the prevalence of the human immunodeficiency virus (HIV) is also high. However, little is known about how these two infections interact. The aim of this study was to compare the proportion of HIV positive (+) and negative (-) individuals who are infected with Taenia solium (TSOL) and who present with clinical and neurological manifestations of cysticercosis (CC).

METHODS

In northern Tanzania, 170 HIV+ individuals and 170 HIV- controls matched for gender, age and village of origin were recruited. HIV staging and serological tests for TSOL antibodies (Ab) and antigen (Ag) were performed. Neurocysticercosis (NCC) was determined by computed tomography (CT) using standard diagnostic criteria. Neurological manifestations were confirmed by a standard neurological examination. In addition, demographic, clinical and neuroimaging data were collected. Further, CD4⁺ cell counts as well as information on highly active antiretroviral treatment (HAART) were noted.

RESULTS

No significant differences between HIV+ and HIV- individuals regarding the sero-prevalence of taeniosis-Ab (0.6% vs 1.2%), CC-Ab (2.4% vs 2.4%) and CC-Ag (0.6% vs 0.0%) were detected. A total of six NCC cases (3 HIV+ and 3 HIV-) were detected in the group of matched participants. Two individuals (1 HIV+ and 1 HIV-) presented with headaches as the main symptom for NCC, and four with asymptomatic NCC. Among the HIV+ group, TSOL was not associated with CD4⁺ cell counts, HAART duration or HIV stage.

CONCLUSIONS

This study found lower prevalence of taeniosis, CC and NCC than had been reported in the region to date. This low level of infection may have resulted in an inability to find cross-sectional associations between HIV status and TSOL infection or NCC. Larger sample sizes will be required in future studies conducted in that area to conclude if HIV influences the way NCC manifests itself.

Changing spatial patterns and increasing rurality of HIV prevalence in the Democratic Republic of the Congo between 2007 and 2013

The Democratic Republic of the Congo (DRC) has one of the lowest HIV prevalence in sub-Saharan Africa, estimated at 1.1% [0.9-1.3] of adults aged 15-49 in 2013 (UNAIDS). Within the 2 million km(2) country, however, there exists spatial variation in HIV prevalence, with the highest HIV prevalence observed in the large cities of Kinshasa and Lubumbashi. Globally, HIV is an increasingly rural disease, diffusing outwards from urban centers of high HIV prevalence to places where HIV was previously absent or present at very low levels. Utilizing data collected during Demographic and Health Surveillance (DHS) in 2007 and 2013 in the DRC, we sought to update the map of HIV prevalence in the DRC as well as to explore whether HIV in the DRC is an increasingly rural disease or remains confined to urban areas. Bayesian kriging and regression indicate that HIV prevalence in rural areas of the DRC is higher in 2013 than in 2007 and that increased distance to an urban area is no longer protective against HIV as it was in 2007. These findings suggest that HIV education, testing and prevention efforts need to diffuse from urban to rural areas just as HIV is doing.

Prevalence and risk factors for sexually transmitted infections in a high-risk occupational group: the case of fishermen along Lake Victoria in Kisumu, Kenya

The aim of this study was to assess prevalence and risk factors for sexually transmitted infections (STIs) among fishermen along Lake Victoria, Kenya. This cross-sectional study surveyed 250 fishermen from beaches in Kisumu District using proportional-to-size sampling based on the number of registered boats per beach. Participants provided demographic and sexual behaviour information, blood for HIV-1 herpes simplex virus type 2 (HSV-2) and syphilis serological tests urine for transcription-mediated amplification assays for Neisseria gonorrhoeae and Chlamydia trachomatis and penile and scrotal swabs for human papillomavirus (HPV) DNA assay. Consistent condom use with the three most recent sexual partners was reported by 30%; 38% reported concurrent sexual partnerships and 65% reported ever having transactional sex. HIV seroprevalence was 26%, HSV-2 seroprevalence by Western blot assay was 58% and 9.5% were rapid plasma reagin and Treponema pallidum particle agglutination assay positive. Genital HPV DNA of any type was detected in 57.2% with 74% of these having two or more HPV types. C. trachomatis and N. gonorrhoeae were detected in 3.2% and 1.2% respectively. Risk factors for syphilis seropositivity included working on multiple beaches during the past year (adjusted odds ratio [AOR] 3.81; 95% confidence interval [CI] 1.29–11.28). HPV infection was associated with owning a radio which is a marker for higher socioeconomic status (AOR 6.33; 95% CI 2.94–7.14) and reporting transactional sex with the most recent sexual partner (AOR 3.03; 95% CI 1.23–7.69). In conclusion, 90% of fishermen had evidence of one or more STIs. This exceptionally high-risk occupational group represents a high priority for preventive interventions.

Profile of adults seeking voluntary HIV testing and counseling in rural Central India: results from a hospital-based study

Rural India has an undetected load of HIV-positive individuals. Few rural adults present for HIV testing and counseling due to stigma, discrimination, and fear of social ostracization. In this rural hospital clinic-based study, we document profiles of rural adults seeking voluntary testing and counseling, and analyze correlates of HIV seropositivity. This cross-sectional study was conducted in 450 participants presenting to the outpatient clinics of Mahatma Gandhi Institute of Medical Sciences, Sevagram, Central India. After informed consent, pre- and post-test counseling, HIV testing, and face-to-face interviews were conducted. Data were collected using a structured questionnaire. The median age of the 450 study participants was 34 years (range 18-88 years); the majority (74%) was married. The overall proportion of HIV seropositivity was 32% [95% CI 28%, 37%]. The proportions of HIV seropositivity in married women, married men, and single men were 41%, 37%, 18%, respectively. No single woman was found seropositive in the study. Very few married women were aware of their husbands' HIV status. In a multivariate analysis, correlates of HIV seropositivity in men were: age 30-39 years, being married, having sex with multiple partners, use of alcohol before sex, and testing positive for HIV in the past. In married women, the only predictor of seropositivity was being married. Although limited by the non-random nature of the sampling method, this pilot study is unique in that it is the first from this rural region of Central India. It provides baseline data on marginalized, largely unstudied populations that may aid in designing probabilistic community-based surveys in this neglected population.

HIV-1, HSV-2 and syphilis among pregnant women in a rural area of Tanzania: prevalence and risk factors

BACKGROUND

Evidence suggests that a substantial proportion of new HIV infections in African countries are associated with herpes simplex virus type 2 (HSV-2). Thus, the magnitude of HSV-2 infection in an area may suggest the expected course of the HIV epidemic. We determined prevalence of genital herpes, syphilis and associated factors among pregnant women from a remote rural Tanzanian community that has a low but increasing HIV prevalence.

METHODS

We analysed 1296 sera and responses to a standard structured questionnaire collected from pregnant women aged between 15-49 years, attending six different antenatal clinics within rural Manyara and Singida regions in Tanzania. Linked anonymous testing (with informed consent) of the serum for specific antibodies against HSV-2 was done using a non-commercial peptide- 55 ELISA. Antibodies against syphilis were screened by using rapid plasma reagin (RPR) and reactive samples confirmed by Treponema pallidum haemagglutination assay (TPHA).

RESULTS

Previous analysis of the collected sera had shown the prevalence of HIV antibodies to be 2%. In the present study the prevalence of genital herpes and syphilis was 20.7% (95% CI: 18.53-23.00) and 1.6% (95% CI: 1.03-2.51), respectively. The presence of HSV-2 antibodies was associated with polygamy (OR 2.2, 95% CI: 1.62 - 3.01) and the use of contraceptives other than condoms (OR 1.7, 95% CI: 1.21 - 2.41). Syphilis was associated with reporting more than one lifetime sexual partner (OR 5.4, 95% CI: 1.88 - 15.76) and previous spontaneous abortion (OR 4.3, 95% CI: 1.52-12.02).

CONCLUSION

The low prevalence of HIV infection offers a unique opportunity for strengthening HIV prevention in a cost-effective manner. The identification and control of other prevalent curable STIs other than syphilis and specific intervention of HSV-2 in specific populations like pregnant women would be one among approaches towards preventing incident HIV infections.

The role of in-migrants in the increasing rural HIV-1 epidemic: results from a village population survey in the Kilimanjaro region of Tanzania

OBJECTIVE

To investigate the magnitude of rural in-migration and the role of in-migrants in the observed increase in HIV-1 prevalence in rural Kilimanjaro, Tanzania.

METHODS

A cross-sectional study involving the adult population aged 15-44 years residing in a rural village was conducted from March to May of 2005. Participants were interviewed regarding their risk behaviors and gave blood for HIV-1 and syphilis testing.

RESULTS

Overall, the response rate was 73.0% (1528/2093). A total of 699 (48.1%) participants reported having in-migrated to the village at some point during their life. The prevalences of HIV-1 infection were 1.8%, 2.3%, and 3.7% among non-in-migrant, long-term in-migrant, and recent in-migrant men, respectively (p(trend)<0.001). The corresponding prevalences among women were 9.2%, 11.5%, and 14.5%, respectively (p(trend)=0.048). The odds of HIV-1 infection were higher among recent in-migrants as compared to non-in-migrants (men: adjusted odds ratio (AOR) 2.4, 95% CI 1.8-6.6; women: AOR 2.3, 95% CI 1.1-5.0). Risk behaviors were inversely related to years since in-migration for both sexes.

CONCLUSIONS

The results suggest that rural in-migration is common for both men and women. In-migrants were at higher risk for HIV-1 infection and contributed significantly to increased rural HIV-1 prevalence. More studies to examine the rate and broader causes of rural in-migration in similar communities are called for. These may help in the design of intervention strategies for curbing the rising rural HIV epidemic.

Predictors of mortality in HIV-infected patients starting antiretroviral therapy in a rural hospital in Tanzania

BACKGROUND

Studies of antiretroviral therapy (ART) programs in Africa have shown high initial mortality. Factors contributing to this high mortality are poorly described. The aim of the present study was to assess mortality and to identify predictors of mortality in HIV-infected patients starting ART in a rural hospital in Tanzania.

METHODS

This was a cohort study of 320 treatment-naïve adults who started ART between October 2003 and November 2006. Reliable CD4 cell counts were not available, thus ART initiation was based on clinical criteria in accordance with WHO and Tanzanian guidelines. Kaplan-Meier models were used to estimate mortality and Cox proportional hazards models to identify predictors of mortality.

RESULTS

Patients were followed for a median of 10.9 months (IQR 2.9-19.5). Overall, 95 patients died, among whom 59 died within 3 months of starting ART. Estimated mortality was 19.2, 29.0 and 40.7% at 3, 12 and 36 months, respectively. Independent predictors of mortality were severe anemia (hemoglobin <8 g/dL; adjusted hazard ratio [AHR] 9.20; 95% CI 2.05-41.3), moderate anemia (hemoglobin 8-9.9 g/dL; AHR 7.50; 95% CI 1.77-31.9), thrombocytopenia (platelet count <150 x 109/L; AHR 2.30; 95% CI 1.33-3.99) and severe malnutrition (body mass index <16 kg/m2; AHR 2.12; 95% CI 1.06-4.24). Estimated one year mortality was 55.2% in patients with severe anemia, compared to 3.7% in patients without anemia (P < 0.001).

CONCLUSION

Mortality was found to be high, with the majority of deaths occurring within 3 months of starting ART. Anemia, thrombocytopenia and severe malnutrition were strong independent predictors of mortality. A prognostic model based on hemoglobin level appears to be a useful tool for initial risk assessment in resource-limited settings.

Trends in HIV-1 prevalence and risk behaviours over 15 years in a rural population in Kilimanjaro region of Tanzania

Background

Monitoring dynamics in HIV-1 infection and risk behaviours is important in evaluating, adjusting and scaling up prevention programmes. The objective of this study was to estimate trends in the prevalence of HIV-1 infection and risk behaviours over 15 years in a rural village population in Kilimanjaro region of Tanzania using repeated population-based cross-sectional surveys.

Methods

Four rounds of HIV-1 sero-epidemiological and behavioural surveys were completed during 1991 to 2005 in the study village. House-to-house registrations of people aged 15–44 years with an address in the village were conducted before each survey. All consenting individuals were then interviewed for pertinent risk behaviours and tested for HIV-1 seropositivity.

Results

Participation proportions ranged from 73.0% to 79.1%. Overall, age and sex-adjusted HIV-1 prevalence increased from 3.2% in 1991 to 5.6 % in 2005 (relative increase 75.0%; p_trend < 0.001). The increase was significant for both men and women (p_trends < 0.001) and more evident among women aged 35–44 years (2.0% to 13.0%, p_trend < 0.001). Among participants aged 15–24 years a decrease in number of sexual partners was observed with a corresponding stable HIV-1 prevalence. Participants aged 25–44 years continued to report multiple sexual partners, and this was corroborated with increased HIV-1 prevalence trend (4.0% to 9.0%, p_trends < 0.001). Among men aged 25–44 years and women aged 15–24 years significant increases in condom use were observed (p_trend < 0.01).

Conclusion

The HIV-1 prevalence seems to have increased among older participants but remained stable among younger participants. Encouraging trends toward safer sex practices were observed among young participants, while only modest behavioural changes were seen among the older participants. Prevention efforts in rural areas need to be intensified and to address people of all ages.