Estimating the mortality risk correcting for high loss to follow-up among female sex workers with HIV in Durban, South Africa, 2018-2021

PURPOSE

This study assesses risk factors of loss to follow-up (LTFU) and estimates mortality risk among female sex workers (FSW) with HIV in Durban, South Africa, in 2018-2021.

METHODS

We used data from the Siyaphambili trial, which evaluated strategies for improved viral suppression. FSW with HIV aged ≥ 18 years with viral load ≥ 50 copies/mL were followed up for 18 months. LTFU was defined as absence from study or intervention visits for 6 months. We traced LTFU participants by calling/in-person visit attempts to ascertain their vital status. We used Cox regression to determine risk factors of LTFU and inverse probability of tracing weights to correct mortality risk.

RESULTS

Of 777 participants, 10 (1.3%) had died and 578 (74.4%) were initially LTFU. Among those LTFU, 36.3% (210/578) were traced successfully, with 6 additional deaths ascertained. Recent physical and sexual violence, and non-viral suppression were associated with increased LTFU. The unweighted and weighted 18-month mortality risks were 2.4% (95% CI: 0.8%-3.9%) and 3.7% (95% CI: 1.8%-5.9%), respectively.

CONCLUSIONS

LTFU is common among FSW with HIV in South Africa with additional investigation of vital status demonstrating under-ascertained mortality. These data suggest the need for comprehensively addressing risks for mortality among FSW.

Polysubstance Use Profiles and HIV Viremia in a South African Cohort of Female Sex Workers: A Latent Class Analysis

BACKGROUND

Given intersecting social and structural factors, female sex workers (FSW) exhibit elevated risk of HIV and substance use. However, there is limited study of how distinct substance use typologies influence HIV treatment outcomes among FSW.

SETTING

A cross-sectional survey with objective viral load assessments of 1391 FSW enrolled into a treatment optimization-focused trial in Durban, South Africa (2018-2020).

METHODS

We used latent class analysis to uncover discrete patterns in past-month self-reported use of the following substances: heavy alcohol use, cannabis, cocaine, crack, ecstasy, methamphetamine, heroin, and Whoonga . We used Wald tests to identify multilevel predictors of latent class membership and multivariable mixture modeling to quantify associations of substance use classes with HIV viremia (≥50 RNA copies/mL).

RESULTS

Substance use (87%) and HIV viremia (62%) were highly prevalent. Latent class analysis uncovered 3 polysubstance use profiles: Heavy Alcohol Use Only (∼54%); Cannabis, Heavy Alcohol, & Crack Use (∼28%); and Whoonga & Crack Use (∼18%). Whoonga & Crack Use was associated with social and structural adversities, including homelessness, outdoor/public sex work, HIV stigma, and violence. Relative to Heavy Alcohol Use Only , HIV viremia was significantly higher in the Whoonga & Crack Use class (adjusted odds ratio 1.97, 95% confidence interval: 1.13 to 3.43), but not in the Cannabis, Heavy Alcohol, & Crack Use class (adjusted odds ratio 1.17, 95% confidence interval: 0.74 to 1.86).

CONCLUSION

HIV viremia differed significantly across identified polysubstance use profiles among South African FSW. Integrating drug treatment and harm reduction services into HIV treatment programs is key to improving virologic outcomes in marginalized communities.

Serological evidence of exposure to Toxoplasma gondii infection in wild birds and local chickens (Gallus gallus domesticus) in Plateau State, North Central Nigeria

Toxoplasma gondii, the cause of toxoplasmosis is an obligate intracellular protozoan parasite of veterinary and public health importance. Ground feeding birds play an active role in the epidemiology of the disease and are the best indicators of soil contamination with the oocysts. Thirteen (14.1%; 95% CI = 7.7-23.0) of the 92 wild birds (6 of Coliformes; 4 of Columbiformes; 67 of Passeriformes and 15 of Piciformes) captured from Shere hills and 43 (9.3%; 95%CI = 4.9-12.4) of the 460 local chickens obtained across 3 senatorial regions of Plateau State, Nigeria were positive for anti-T. gondii antibodies using enzyme linked immunosorbent assay (ELISA). Varying prevalence (16.7-100%) of anti-T. gondii antibodies were recorded across 10 of 35 wild bird species; 2 (28.6) of 7 African thrush (Turdus pelios), 2 (33.3) of 6 speckled mouse bird (Colius striatus), 1 (20.0%) of 5 speckled fronted weaver (Sporopipes frontalis), 1 (33.3%) of 3 Northern Red bishop (Euplectes franciscanus), 1 (50.0%) of 2 village weaver (Ploceus cucullatus), 2 (28.6%) of 7 common bulbul (Pycnonotus barbatus), 1 (50.0%) of 2 black crowned tchagra (Tchagra senegalus), 1 (50.0%) of 2 black billed wood dove (Turtur abyssinicus), 1 (100.0%) of 1 mocking cliff chat (Thamnolaea cinamomeiventris), 1 (16.7) of 6 vieillot's barbet (Lybius vieilloti). The prevalence did not vary significantly based on the sex (p = 0.14), feeding guild (p = 0.53) and the taxonomic order (p = 0.62) of the wild birds. Regional based prevalence among local chickens ranged between 8.0 and 11.8% across the 3 senatorial zones. The source (p = 0.513; 95% CI = 4.9-16.8) and age (p = 0.797; 95% CI = 4.9-16.8) of local chickens were not associated with T. gondii seropositivity. Seropositivity was higher in the females (95% CI = 9.1-18.3) than in the males (p = 0.004; 95% CI = 3.0-9.4). This is the first report of the serological evidence of exposure to T. gondii infection in a wide variety of wild birds and local chickens in the area. It suggest that birds in this region are important asymptomatic intermediate hosts and play a role in the maintenance of the organism in the ecosystem.