Safety and immunogenicity of an inactivated SARS-CoV-2 vaccine (CoronaVac) in inadvertently vaccinated healthy children.

Twenty-seven children aged seven months to 5 years were inadvertently vaccinated with a COVID-19 vaccine, the CoronaVac (Sinovac, China), an inactivated SARS-CoV-2 vaccine, in two different cities of Sao Paulo State, Brazil. After the event, these children were monitored by local pediatricians and serum samples were collected at the first visit and 30 days after vaccination and tested for SARS-CoV-2 S1 serology with Ortho total IgG anti-S1 protein and Cpass, an ACE2 receptor binding domain inhibition assay. Only one child had a mild symptom after vaccination, with no other adverse events documented up to the 30 days follow-up. Of 27 children tested 3-9 days after vaccination, 5 (19%) had positive serology suggesting a previous natural SARS-CoV-2 infection, with all 19 tested on day 30 after vaccination and presenting with positive tests, with an increment of antibody titers in those initially positive. A low Cpass binding inhibition was observed in the first collection in 11 seronegative cases, with high titers among those anti-S1 positive. All children showed an important increase in antibody titers on day 30. The event allowed the documentation of a robust serological response to one dose of CoronaVac in this small population of young children, with no major adverse effects. Although it was an unfortunate accident, this event may contribute with future vaccine strategies in this age group. The data suggest that CoronaVac is safe and immunogenic for children.

HIV prevalence among men who have sex with men in Brazil: results of the 2nd national survey using respondent-driven sampling.

This paper reports human immuno-deficiency virus (HIV) prevalence in the 2nd National Biological and Behavioral Surveillance Survey (BBSS) among men who have sex with men (MSM) in 12 cities in Brazil using respondent-driven sampling (RDS).Following formative research, RDS was applied in 12 cities in the 5 macroregions of Brazil between June and December 2016 to recruit MSM for BBSS. The target sample size was 350 per city. Five to 6 seeds were initially selected to initiate recruitment and coupons and interviews were managed online. On-site rapid testing was used for HIV screening, and confirmed by a 2nd test. Participants were weighted using Gile estimator. Data from all 12 cities were merged and analyzed with Stata 14.0 complex survey data analysis tools in which each city was treated as its own strata. Missing data for those who did not test were imputed HIV+ if they reported testing positive before and were taking antiretroviral therapy.A total of 4176 men were recruited in the 12 cities. The average time to completion was 10.2 weeks. The longest chain length varied from 8 to 21 waves. The sample size was achieved in all but 2 cities.A total of 3958 of the 4176 respondents agreed to test for HIV (90.2%). For results without imputation, 17.5% (95%CI: 14.7-20.7) of our sample was HIV positive. With imputation, 18.4% (95%CI: 15.4-21.7) were seropositive.HIV prevalence increased beyond expectations from the results of the 2009 survey (12.1%; 95%CI: 10.0-14.5) to 18.4%; CI95%: 15.4 to 21.7 in 2016. This increase accompanies Brazil's focus on the treatment to prevention strategy, and a decrease in support for community-based organizations and community prevention programs.

Isolation of infectious Zika virus from a urine sample cultured in SIRC cells from a patient suspected of having rubella virus.

A great variety of viruses which cause exanthema share other clinical manifestations, making the etiologic identification a very difficult task, relying exclusively on the clinical examination. Rubella virus (RV) infection during the early stages of pregnancy can lead to serious birth defects, known as congenital rubella syndrome (CRS). In the present report, we described the presence of Zika virus (ZIKV) particles in urine samples and also ZIKV isolation in SIRC cells from the urine of a patient in acute phase of suspected rubella disease. The 50-year-old unvaccinated woman living in Sao Paulo, Brazil, was admitted to the emergency room with fever, headache, rash, arthralgia and prostration. Urine samples were collected for virus isolation and RT-qPCR. SIRC and Vero cells were inoculated with urine samples during 7 days. RT-qPCR was performed using measles virus (MV) and RV primers and both were found to be negative. After this result, RT-qPCR was performed for parvovirus B19, herpes virus 6 and ZIKV. The urine sample and the isolate were positive by Real Time PCR for ZIKV and negative for all other viruses tested. The sequences isolated are from the Asiatic lineage.

The influence of HIV-1 subtypes C, CRF31_BC and B on disease progression and initial virologic response to HAART in a Southern Brazilian cohort.

BACKGROUND: Although most HIV-1 infections in Brazil are due to subtype B, Southern Brazil has a high prevalence of subtype C and recombinant forms, such as CRF31_BC. This study assessed the impact of viral diversity on clinical progression in a cohort of newly diagnosed HIV-positive patients. METHODS: From July/2004 to December/2005, 135 HIV-infected patients were recruited. The partial pol region was subtyped by phylogeny. A generalized estimating equation (GEE) model was used to examine the relationship between viral subtype, CD4+ T cell count and viral load levels before antiretroviral therapy. Hazard ratio (Cox regression) was used to evaluate factors associated with viral suppression (viral load < 50 copies/mL at six months). RESULTS: Main HIV-1 subtypes included B (29.4%), C (28.2%), and CRF31_BC (23.5%). Subtypes B and C showed a similar trend in CD4+ T cell decline. Comparison of non-B (C and CRF31_BC) and B subtypes revealed no significant difference in the proportion of patients with viral suppression at six months (week 24). Higher CD4+ T cell count and lower viral load were independently associated with viral suppression. CONCLUSION: No significant differences were found between subtypes; however, lower viral load and higher CD4+ T cell count before therapy were associated with better response.

The influence o hiv-1 subtypes c, crf31_bc andb on disease progression and innitial virologic response to haart in a southern Brazilian cohort / A influência dos subtipos C, CRF31_BC e B do vírus HIV-1 na progressão da infecção e resposta virológica inicial a terapia antirretroviral em uma coorte no sul do Brasil

Background: Although most HIV-1 infections in Brazil are due to subtype B, Southern Brazil has a high prevalence of subtype C and recombinant forms, such as CRF31_BC. This study assessed the impact of viral diversity on clinical progression in a cohort of newly diagnosed HIV-positive patients. Methods: From July/2004 to December/2005, 135 HIV-infected patients were recruited. The partial pol region was subtyped by phylogeny. A generalized estimating equation (GEE) model was used to examine the relationship between viral subtype, CD4+ T cell count and viral load levels before antiretroviral therapy. Hazard ratio (Cox regression) was used to evaluate factors associated with viral suppression (viral load < 50 copies/mL at six months). Results: Main HIV-1 subtypes included B (29.4%), C (28.2%), and CRF31_BC (23.5%). Subtypes B and C showed a similar trend in CD4+ T cell decline. Comparison of non-B (C and CRF31_BC) and B subtypes revealed no significant difference in the proportion of patients with viral suppression at six months (week 24). Higher CD4+ T cell count and lower viral load were independently associated with viral suppression. Conclusion: No significant differences were found between subtypes; however, lower viral load and higher CD4+ T cell count before therapy were associated with better response.

Introdução: Embora a maioria das infecções de HIV-1 no Brasil seja devido ao subtipo B, o Sul do Brasil apresenta uma alta prevalência do subtipo C e formas recombinantes, como CRF31_BC. Este estudo avaliou o impacto da diversidade viral na evolução clínica em uma coorte de pacientes HIV-positivos recém diagnosticados. Métodos: De julho/2004 a dezembro/2005, 135 pacientes anti-HIV reagentes foram recrutados. A região pol parcial foi subtipada por filogenia. Um modelo de equação de estimativa generalizada (GEE) foi utilizado para examinar a relação entre subtipo viral, contagem de células CD4 e níveis de carga viral pré-terapia antirretroviral. Hazard ratio (regressão de Cox) foi utilizada para avaliar os fatores associados à supressão viral (carga viral < 50 cópias/mL em seis meses). Resultados: Os principais subtipos de HIV-1 incluíram B (29,4%), C (28,2%) e CRF31_BC (23,5%). Os subtipos B e C apresentaram uma tendência semelhante no declínio de células CD4. Quando comparados os subtipos não B (C e CRF31_BC) e B, não houve diferença significativa na proporção de pacientes com supressão viral aos seis meses (24 semanas). CD4 mais alto e carga viral mais baixa demonstraram associação independente com supressão viral. Conclusão: Não houve diferença significativa entre os subtipos; entretanto, viremia mais baixa e CD4 mais alto pré-terapia mostraram associação com melhor resposta.

Low prevalence of primary antiretroviral resistance mutations and predominance of HIV-1 clade C at polymerase gene in newly diagnosed individuals from south Brazil.

We describe preliminary molecular characterization of HIV-1 pol from 108 consecutive HIV seropositive users of a Voluntary Counseling and Testing (VCT) site of Porto Alegre city, the major metropolitan area in the south of Brazil. Protease and partial reverse transcriptase regions were retrotranscribed from plasma HIV-1 RNA and sequenced after direct nested PCR. Principal antiretroviral resistance mutations (ARM) were observed in 3% of the samples, two cases with K103N and one with M41L, L210W and T215Y, all in HIV-1 clade B infected men. At protease region, no principal mutations were observed, but polymorphisms at secondary codons were frequent. Contrary to other areas in the country where clade B dominates, HIV-1 clade C genomes predominated in this study (58%), clade B (32%) and clade F1 (3%). Of the genomes clustering in clade C, almost half (43%) had a small clade B segment at reverse transcriptase, forming a sub-cluster within clade C with a similar recombinant structure and carrying new amino acid signatures. Other mosaic genomes were also observed (7%). The low prevalence of resistance mutations is consistent with previous observations at this geographical location but the high frequency of HIV-1 clade C and CB mosaics seems pre-eminent and warns close monitoring.