HIV self-test: a tool to expand test uptake among men who have sex with men who have never been tested for HIV in São Paulo, Brazil.

OBJECTIVES: HIV self-testing is an effective tool to improve diagnostic coverage in key populations, enabling linkage to care and access to antiretroviral therapy. Its implementation requires better understanding of patients' perspectives on this novel strategy. The aim of the study was to investigate the perception of men who have sex with men (MSM) regarding the HIV oral fluid self-test (HIVST) in São Paulo, Brazil, and to analyse the sociodemographic characteristics and testing strategy preferences of individuals registered to undertake HIVST. METHODS: Preceding the implementation of HIVST use as public policy in 2019, we recruited MSM living in São Paulo to undertake HIVST using a digital platform, and investigated their sociodemographic profiles, testing experiences and testing preferences. Results were compared according to reported lifetime HIV testing. RESULTS: A total of 6477 MSM (median age 28 years) were recruited to the study from April 9th to December 31st, 2018. Seventy-eight per cent reported previous HIV testing. The opening hours of health facilities (53%), concern about disclosing intimate personal information to health care providers (34%) and fear of stigma (21%) were reported as the main barriers to testing. Older age, higher education, illicit drug use and self-identifying as gay were associated with prior HIV testing (P < 0.001). Most participants (67%) were unaware that HIVST was available before enrolling in the study. Preference for HIVST over other testing technologies was higher among those never tested (71%) than among participants with previous HIV testing (61%; P < 0.001). CONCLUSIONS: HIVST was found to be an effective tool to improve testing uptake among MSM, particularly those who had never been tested before. Characterization of the most likely users of HIVST among MSM will help to inform implementation and scaling up of this novel testing method in the Brazilian public health system.

Positive selection results in frequent reversible amino acid replacements in the G protein gene of human respiratory syncytial virus.

Human respiratory syncytial virus (HRSV) is the major cause of lower respiratory tract infections in children under 5 years of age and the elderly, causing annual disease outbreaks during the fall and winter. Multiple lineages of the HRSVA and HRSVB serotypes co-circulate within a single outbreak and display a strongly temporal pattern of genetic variation, with a replacement of dominant genotypes occurring during consecutive years. In the present study we utilized phylogenetic methods to detect and map sites subject to adaptive evolution in the G protein of HRSVA and HRSVB. A total of 29 and 23 amino acid sites were found to be putatively positively selected in HRSVA and HRSVB, respectively. Several of these sites defined genotypes and lineages within genotypes in both groups, and correlated well with epitopes previously described in group A. Remarkably, 18 of these positively selected tended to revert in time to a previous codon state, producing a "flip-flop" phylogenetic pattern. Such frequent evolutionary reversals in HRSV are indicative of a combination of frequent positive selection, reflecting the changing immune status of the human population, and a limited repertoire of functionally viable amino acids at specific amino acid sites.

Dramatic improvement in survival among adult Brazilian AIDS patients.

BACKGROUND: Since the last study of survival time among Brazilian AIDS patients, care has improved steadily, culminating in a controversial policy of universal free access to triple antiretroviral treatment since 1996. This large, national study examined how these changes have impacted survival. METHODS: Using national data for cases diagnosed in 1995 and 1996, we randomly selected 3930 adult AIDS cases from 18 cities in seven states representing all regions of Brazil. Trained abstracters reviewed medical records, determining dates of diagnosis and death or last contact, exposure category, treatment, and demographics. After review, 2821 cases met the inclusion criteria and were available for Kaplan-Meier and proportional hazards analysis. Data from the earlier study were re-analyzed for comparison. RESULTS: Median survival was 5 months for cases diagnosed in the 1980s, 18 months for those diagnosed in 1995, and 58 months for those diagnosed in 1996. Predictors of longer survival in univariate analysis included antiretroviral treatment, year of diagnosis, higher education, sexual exposure category, female sex, and Pneumocystis carinii pneumonia prophylaxis. In multivariate analysis, the predictive value of most of these was attenuated or disappeared, leaving antiretroviral treatment as the main predictor of survival. CONCLUSIONS: Survival time has increased substantially for adult Brazilian AIDS patients. The timing of these gains and analysis of the predictors of survival both indicate antiretroviral treatment as the cause. These findings demonstrate that universal access to antiretroviral treatment in a developing country can produce benefits on the same scale as in richer countries.

Social networks shape the transmission dynamics of hepatitis C virus.

Hepatitis C virus (HCV) infects 170 million people worldwide, and is a major public health problem in Brazil, where over 1% of the population may be infected and where multiple viral genotypes co-circulate. Chronically infected individuals are both the source of transmission to others and are at risk for HCV-related diseases, such as liver cancer and cirrhosis. Before the adoption of anti-HCV control measures in blood banks, this virus was mainly transmitted via blood transfusion. Today, needle sharing among injecting drug users is the most common form of HCV transmission. Of particular importance is that HCV prevalence is growing in non-risk groups. Since there is no vaccine against HCV, it is important to determine the factors that control viral transmission in order to develop more efficient control measures. However, despite the health costs associated with HCV, the factors that determine the spread of virus at the epidemiological scale are often poorly understood. Here, we sequenced partial NS5b gene sequences sampled from blood samples collected from 591 patients in São Paulo state, Brazil. We show that different viral genotypes entered São Paulo at different times, grew at different rates, and are associated with different age groups and risk behaviors. In particular, subtype 1b is older and grew more slowly than subtypes 1a and 3a, and is associated with multiple age classes. In contrast, subtypes 1a and 3b are associated with younger people infected more recently, possibly with higher rates of sexual transmission. The transmission dynamics of HCV in São Paulo therefore vary by subtype and are determined by a combination of age, risk exposure and underlying social network. We conclude that social factors may play a key role in determining the rate and pattern of HCV spread, and should influence future intervention policies.