The impact of the COVID-19 pandemic among migrants in shelters in Tijuana, Baja California, Mexico.

INTRODUCTION: Migrants, especially those in temporary accommodations like camps and shelters, might be a vulnerable population during the COVID-19 pandemic, but little is known about the impact of the pandemic in these settings in low-income and middle-income countries. We assessed SARS-CoV-2 seropositivity and RNA prevalence, the correlates of seropositivity (emphasising socially determined conditions), and the socioeconomic impacts of the pandemic among migrants living in shelters in Tijuana, a city on the Mexico-US border. METHODS: We conducted a cross-sectional, non-probability survey of migrants living in shelters in Tijuana in November-December 2020 and February-April 2021. Participants completed a questionnaire and provided anterior nasal swab and blood samples for detection of SARS-CoV-2 RNA and antibodies (IgG and IgM), respectively. We explored whether SARS-CoV-2 infection was associated with sociodemographic and migration-related variables, access to sanitation, protective behaviours and health-related factors. RESULTS: Overall, 481 participants were enrolled, 67.7% from Northern Central America, 55.3% women, mean age 33.2 years. Seven (1.5%) participants had nasal swabs positive for SARS-CoV-2 RNA and 53.0% were SARS-CoV-2 seropositive. Avoiding public transportation (OR 0.59, 95% CI 0.39 to 0.90) and months living in Tijuana (OR 1.06, 95% CI 1.02 to 1.10) were associated with seropositivity. Sleeping on the streets or other risky places and having diabetes were marginally associated with seropositivity. Most participants (90.2%) had experienced some socioeconomic impact of the pandemic (eg, diminished income, job loss). CONCLUSION: Compared with results from other studies conducted in the general population in Mexico at a similar time, migrants living in shelters were at increased risk of acquiring SARS-CoV-2, and they suffered considerable adverse socioeconomic impacts as a consequence of the pandemic. Expanded public health and other social support systems are needed to protect migrants from COVID-19 and reduce health inequities.

Cross-sectional study of endothelial function in HIV-infected patients in Brazil.

Antiretroviral therapy (ART) in HIV-infected patients has been associated with an increased risk of cardiovascular disease. This study evaluates vascular endothelial dysfunction of the peripheral circulation in Brazilian HIV-infected subjects on ART or naive to ART compared to a control group matched for age and body mass index (BMI). We performed a cross-sectional comparative study to measure postischemic peak flow-mediated dilation (FMD) of the brachial artery and the response to glyceryl trinitrate (GTN) in HIV-infected patients and healthy controls in Salvador, Bahia, Brazil. Endothelial vasomotor function was evaluated by assessing brachial artery FMD. Forty-four HIV-infected individuals (33 ARV treated and 11 ART naive) were compared to 25 healthy controls matched for age and BMI. FMD % was significantly lower for the ART-experienced patients compared to the ART-naive patients and was also significantly different from controls (ART experienced 8.2 +/- 6.0% vs. 19.3 +/- 4.8% vs. 23.3 +/- 6.1%), respectively (p < 0.0001). The cholesterol, triglyceride, and ALT levels were significantly higher in the ART-experienced group compared to the ART-naive and control subjects (p < 0.028); however, linear regression analysis revealed a statistically significant association of endothelial dysfunction as a dependent variable only with ARV treatment in HIV-infected subjects (p = 0.03). The association of endothelial dysfunction with ARV therapy in HIV-infected patients was independent of protease inhibitor-containing regimens or dyslipidemia. This dysfunction may contribute to the risk for HIV-associated atherosclerosis.

Immunogenetics of CD4 lymphocyte count recovery during antiretroviral therapy: An AIDS Clinical Trials Group study.

During antiretroviral therapy, CD4 lymphocyte count increases are modest in some patients despite virologic control. We explored whether polymorphisms in genes important for T cell expansion, survival, and apoptosis are associated with the magnitude of CD4 lymphocyte count recovery during antiretroviral therapy. We studied treatment-naive individuals who achieved sustained control of plasma viremia (<400 HIV-1 RNA copies/mL) for at least 48 weeks after initiation of antiretroviral therapy and compared genotypes among individuals who had an increase of either <200 or > or =200 CD4 cells/mm3 from baseline. A total of 137 single-nucleotide polymorphisms across 17 genes were characterized in 873 study participants. In multivariate analyses that controlled for clinical variables, polymorphisms in genes encoding tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), TNF- alpha , Bcl-2-interacting molecule (Bim), interleukin (IL)-15, and IL-15 receptor alpha chain (IL-15R alpha ) were associated with the magnitude of the increase in CD4 lymphocyte count, as were haplotypes in genes encoding interferon- alpha , IL-2, and IL-15R alpha (P < .05, for each). Multifactor dimensionality reduction identified a gene-gene interaction between IL-2/IL-15 receptor common beta chain and IL-2/IL-7/IL-15 receptor common gamma chain. Immune recovery during antiretroviral therapy is a complex phenotype that is influenced by multiple genetic variants. Future studies should validate these tentative associations and define underlying mechanisms.