With the large number of individuals infected and recovered from Covid-19, there is intense discussion about the quality and duration of the immunity elicited by SARS-CoV-2 infection, including the possibility of disease recurrence. Here we report a case with strong clinical, epidemiological and laboratorial evidence of, not only reinfection by SARS-CoV-2, but also clinical recurrence of Covid-19.

Objective To define the prevalence of adverse outcomes of maternal infection in a large cohort of ZIKV-infected Brazilian women and their infants. Design Prospective population-based cohort study. Setting Ribeirão Preto's region's private and public health facilities. Population Symptomatic ZIKV-infected mothers and their infants. Methods Prenatal/early neonatal data were obtained for all mother-child pairs. A subgroup of infants had cranial ultrasonography, eye fundoscopy, hearing and neurological examinations and Bayley III screening tests within 3 months of age. Conclusions This prospective population-based study represents the largest Brazilian cohort study of ZIKV in pregnancy. Congenital anomalies potentially associated with CZS are less frequent than previously thought. There is a strong association between the gestational age of infection (≤11 weeks) and a poorer early infant prognosis. A notable proportion of apparently asymptomatic newborns can present with subclinical findings within 3 months of age.

Introduction: This epidemiological household survey aimed to estimate the prevalence of the current and past SARS-CoV-2 infections in Ribeirão Preto, a municipality of southeast Brazil. Methods: The survey was conducted in two phases using a clustered sampling scheme. The first phase spanned May 1-3 and involved 709 participants. The second phase spanned June 11-14, 2020, and involved 646 participants. Results: During the first phase, RT-PCR performed on nasopharyngeal swabs was positive at 0.14%. The serological tests were positive in 1.27% of the patients during the first phase and 2.79% during the second phase. People living in households with more than five members had a prevalence of 10.83% (95%CI: 1.58-74.27) higher than those living alone or with someone other. Considering the proportion of the positive serological test results with sex and age adjustments, approximately 2.37% (95%CI: 1.32-3.42) of the population had been cumulatively infected by mid-June 2020, which is equivalent to 16,670 people (95%CI: 9,267-24,074). Considering that 68 deaths from the disease in the residents of the city had been confirmed as at the date of the second phase of the survey, the infection fatality rate was estimated to be 0.41% (95%CI: 0.28-0.73). Our results suggest that approximately 88% of the cases of SARS-CoV-2 infection at the time of the survey were not reported to the local epidemiological surveillance service. Conclusions: The findings of this study provide indepth knowledge of the COVID-19 pandemic in Brazil and are helpful for the preventive and decision-making policies of public managers.

Objectives: Hepatitis A virus (HAV) infection is considered highly endemic in Brazil, especially in lowincome areas. In contrast, only a few human cases of hepatitis E have been reported. This study aimed to estimate the prevalence and potential risk factors of HAV and hepatitis E virus (HEV) infections in an adult population from a rural township of southeastern Brazil. Methods: We conducted a cross-sectional survey using serum samples from urban and rural residents of Cássia dos Coqueiros, São Paulo state. A total of 990 samples were tested for anti-HAV IgG by chemiluminescent microparticle immunoassay, and a subset of 248 samples tested for anti-HEV IgG, using two commercial ELISA. Variables associated with anti-HAV and anti-HEV positivity were assessed by a multivariate analysis using a binomial logistic regression model. Results: Seroprevalence of HAV and HEV was 89.1% and 20.7%, respectively. Age was significantly associated with HAV infection. Wantai and Mikrogen ELISA yielded comparable HEV seroprevalence results. Conclusions: Anti-HAV seroprevalence has declined and correlates with age, whereas anti-HEV was significantly higher than that found in previous population-based studies. These results indicate a need for further investigations of the magnitude of HEV infection in Brazil using the currently available, more sensitive diagnostic methods.