ABSTRACT Introduction Hepatitis C virus (HCV) can be vertically transmitted from mother to fetus. We evaluated knowledge about HCV vertical transmission in female blood donors who became pregnant following detection of HCV in their donated blood. Methods This was a retrospective descriptive study of females seen at a single blood bank in Sao Paulo, Brazil who were diagnosed with HCV infection in their donated blood. HCV-infected donors who subsequently became pregnant were invited to participate through letters or phone calls. Individuals who agreed to participate were interviewed by questionnaire to evaluate their knowledge on HCV vertical transmission. Results Among 282 HCV-positive female blood donors, 69 reported becoming pregnant after their HCV diagnosis in donated blood. While 24 of these women were successful treated for their infection prior to becoming pregnant, 45 (65.2%) were at risk for vertical HCV transmission either because they had never been treated for HCV, were pregnant before treatment or became pregnant after unsuccessful treatment. Of the 59 women who responded to the question of whether they were informed about the risk of HCV vertical transmission, 58 (98.3%) reported never receiving this information either after obtaining their blood donation results or during their pregnancy. Conclusion The lack of knowledge of HCV-infected women on the possibility for mother-to-child transmission of this virus highlights the critical need to improve communication about pregnancy-related risks between health professionals and HCV-infected women of childbearing age.

ABSTRACT The prevalence of immunity to Chikungunya virus (CHIKV) in pregnant women and newborns in the Western Brazilian Amazon was assessed at a time when previous studies did not report chikungunya fever in the area. In 435 asymptomatic pregnant women and 642 healthy unrelated newborns, the presence of IgM and IgG antibodies to CHIKV were determined by a commercial ELISA. All participants were negative to IgM anti-CHIKV. Anti-CHIKV IgG was identified in 41 (9.4%) pregnant women and 66 (10.3%) newborns. The presence of anti-CHIKV IgG was positively associated with the lowest socioeconomic status in pregnant women (OR 2.54, 95% CI 1.15-5.62, p=0.021) and in the newborns’ mothers (OR 5.10, 95% CI 2.15-12.09, p< 0.001). Anti-CHIKV IgG was also associated with maternal age in both, the pregnant women (OR 1.06, 95% CI 1.00-1.11, p=0.037) and the newborns’mothers (OR 1.08, 95% CI 1.03-1.12, p=0.001). Pregnancy outcomes in which the mother or the newborn was anti-CHIKV IgG positive proceeded normally. Negative CHIKV serology was associated with being positive for DENV antibodies and having had malaria during pregnancy. These findings showed that there was already a silent circulation of CHIKV in this Amazon region before the first outbreak of chikungunya fever. Furthermore, seropositivity for CHIKV was surprisingly frequent (10%) in both, pregnant women and newborns, affecting mainly low-income women.

ABSTRACT Vaccination is a fundamental tool to prevent SARS-CoV-2 infection and to limit the COVID-19 pandemic. The emergence of SARS-CoV-2 variants with multiple mutations has raised serious concerns about the ability of neutralizing antibody responses elicited by prior vaccination to effectively combat these variants. The neutralizing capacity against the Gamma, Delta and Omicron variants of sera from individuals immunized with the CoronaVac vaccine remains incompletely determined. The present study evaluated 41 health care workers at the Faculdade de Medicina of the Universidade de Sao Paulo, in Sao Paulo, Brazil, naive to previous SARS- CoV-2 infection, who were vaccinated with two doses of the CoronaVac SARS-CoV-2 vaccine 28 days apart. Neutralizing antibody levels against the Gamma, Delta, and Omicron variants were measured at 32 and 186 days after the second vaccination. We also measured neutralizing antibodies against Omicron in 34 of these individuals following a subsequent booster immunization with the Pfizer vaccine. Quantification of neutralizing antibodies was performed using the Cytopathic Effect-based Virus Neutralization test. Neutralization antibody activity against the Gamma, Delta and Omicron variants was observed in 78.0%, 65.9% and 58.5% of serum samples, respectively, obtained at a mean of 32 days after the second immunization. This decreased to 17.1%, 24.4% and 2.4% of sera having activity against Delta, Gamma and Omicron, respectively, at 186 days post-vaccination. The median neutralizing antibody titers at 32 days were 1:40, 1:20 and 1:20 against Gamma, Delta and Omicron, respectively, and decreased to an undetectable median level against all variants at the later time. A booster immunization with the Pfizer vaccine elicited neutralizing antibodies against Omicron in 85% of subjects tested 60 days after vaccination. We conclude that two doses of the CoronaVac vaccine results in limited protection of short duration against the Gamma, Delta and Omicron SARS-CoV-2 variants. A booster dose with the Pfizer vaccine induced antibody neutralizing activity against Omicron in most patients which was measurable 60 days after the booster.

ABSTRACT Background: Despite their worldwide occurrence, the distribution and role of insect-specific flaviviruses (ISFs) remain unclear. Methods: We evaluated the presence of ISFs in mosquitoes collected in São Paulo, Brazil, using reverse transcription and semi-nested polymerase chain reaction (PCR). Some of the positive samples were subjected to nanopore sequencing. Results: Twelve mosquito pools (2.8%) tested positive for flavivirus infection. Nanopore sequencing was successfully performed on six samples. Phylogenetic analysis grouped these sequences into genotype 2 of Culex flavivirus (CxFV). Conclusions: The identification of CxFV genotype 2 at new locations in São Paulo highlights the importance of understanding the role of ISFs in mosquito vector competence.

Abstract Objective We sought to describe the prevalence of microcephaly and to compare the different cutoff points established by the Brazilian Ministry of Health at various times during a Zika virus epidemic. As a secondary aim, we investigated the possible etiology of the microcephaly. Method This retrospective study utilized newborn participants in the Zika Cohort Study Jundiaí. Newborns from the Zika Cohort Study Jundiaí with an accurate gestational age determination and complete anthropometric data were analyzed, and microcephaly was diagnosed according to the INTERGROWTH-21st curve. At delivery, fluids were tested for specific antibodies and for viruses. Brain images were evaluated for microcephaly. Receiver Operating Characteristic curves were plotted to define the accuracy of different cutoff points for microcephaly diagnosis. Results Of 462 eligible newborns, 19 (4.1%) were positive for microcephaly. Cutoff points corresponding to the curves of the World Health Organization yielded the best sensitivity and specificity. Three of the microcephaly cases (15.8%) were positive for Zika virus infections; nine (47.4%) had intrauterine growth restriction; one had intrauterine growth restriction and was exposed to Zika virus; three had a genetic syndrome (15.8%); and three had causes that had not been determined (15.8%). Conclusions Microcephaly prevalence was 4.1% in this study. Cutoff values determined by the World Health Organization had the highest sensitivity and specificity in relation to the standard IG curve. The main reason for microcephaly was intrauterine growth restriction. All possible causes of microcephaly must be investigated to allow the best development of an affected baby.

ABSTRACT OBJECTIVE To evaluate the performance of post mortem laboratory analysis in identifying the causes of hemorrhagic fever and/or neuroinvasive disease in deaths by arbovirus infection. METHODS Retrospective cross-sectional study based on the differential analysis and final outcome obtained in patients whose samples underwent laboratory testing for arboviruses at the Pathology Center of the Adolfo Lutz Institute, in São Paulo, Brazil. RESULTS Of the 1355 adults clinically diagnosed with hemorrhagic fever and/or neuroinvasive disease, the most commonly attributed cause of death and the most common final outcome was dengue fever. Almost half of the samples tested negative on all laboratory tests conducted. CONCLUSION The failure to identify the causative agent in a great number of cases highlights a gap in the diagnosis of deaths of unknown etiology. Additional immunohistochemical and molecular assessments need to be added to the post-mortem protocol if all laboratory evaluations performed fail to identify a causative agent. While part of our findings may be due to technical issues related to sample fixation, better information availability when making the initial diagnosis is crucial. Including molecular approaches might lead to a significant advancement in diagnostic accuracy.

ABSTRACT OBJECTIVE To evaluate the performance of post mortem laboratory analysis in identifying the causes of hemorrhagic fever and/or neuroinvasive disease in deaths by arbovirus infection. METHODS Retrospective cross-sectional study based on the differential analysis and final outcome obtained in patients whose samples underwent laboratory testing for arboviruses at the Pathology Center of the Adolfo Lutz Institute, in São Paulo, Brazil. RESULTS Of the 1355 adults clinically diagnosed with hemorrhagic fever and/or neuroinvasive disease, the most commonly attributed cause of death and the most common final outcome was dengue fever. Almost half of the samples tested negative on all laboratory tests conducted. CONCLUSION The failure to identify the causative agent in a great number of cases highlights a gap in the diagnosis of deaths of unknown etiology. Additional immunohistochemical and molecular assessments need to be added to the post-mortem protocol if all laboratory evaluations performed fail to identify a causative agent. While part of our findings may be due to technical issues related to sample fixation, better information availability when making the initial diagnosis is crucial. Including molecular approaches might lead to a significant advancement in diagnostic accuracy.

ABSTRACT Background: An efficient mobilization and collection of peripheral blood stem cells (PBSCs) are crucial to optimize engraftment in the recipient. We aim to validate a formula that predicted CD34+ cell yield and to describe variables that correlated with high yield mobilization and collection in healthy donors. Methods: We retrospectively analyzed clinical and laboratory data from healthy donors who underwent PBSC collection from 2006 to 2015. The predicted number of collected cells was calculated using the following formula: Total number of CD34+ (cells × 106/kg) yield = [(peripheral CD34+ cells/µL) × (0.43)/recipient body weight (kg)] × total liters processed. Results: We evaluated 338 collections from 307 allogeneic PBSC donors. The predicted versus the observed number of CD34+ cells/kg collected yielded an r-value of 0.775 (0.726-0.816; p < 0.0001). Overall, 55.7% donors had an acceptable mobilization level. Donors with a body weight <67 kg were less likely to yield a satisfactory CD34+ cell count (OR = 0.44; 95% CI 0.24-0.81), while a white blood cell (WBC) count >40 × 109/L (OR = 3.69; 2.11-6.46) and platelet count ≥200 × 109/L (OR = 2.09; 1.26-3.47) on the day of collection predicted a good level of mobilization. Predictors of a CD34+ cell yield/kg of ≥4 × 106 with only one apheresis session were: circulating CD34+ cells/µL >40 (OR = 16; 6.94-36.93), hemoglobin ≥14 g/dL (OR = 3.40; 1.53-7.57), WBC >40 × 109/L (OR = 4.61; 2.10-10.10) on the first collection day, and a positive delta weight between donor and recipient (OR = 3.10; 1.36-7.06). Conclusion: The formula for predicting CD34+ cell yield is accurate and suggests the optimal length of time for successful leukapheresis. Validation of the predictors of successful mobilization will help to further refine PBSC leukapheresis procedures.

ABSTRACT Surveillance of Rotavirus A (RVA) throughout the national territory is important to establish a more complete epidemiological-molecular scenario of this virus circulation in Brazil. The aim of the present study was to investigate the genetic diversity of RVA strains circulating in Tocantins State (Northern Brazil) during six years of post-vaccination follow-up (2010-2016). A total of 248 stool samples were screened by next generation sequencing and 107 (43.1%) nearly full length RVA genome sequences were obtained; one sample was co-infected with two RVA strains (G2/G8P[4]). Six G and P genotypes combinations were detected: G12P[8] strains (78.6%), as well as the G3P[8] (9.3%) and G1P[8] (0.9%) were associated with a Wa-like genogroup backbone. All G2P[4] (5.6%) and G8P[4] (2.8%) strains, including the mixed G2/G8P[4] infection (0.9%) showed the DS-1-like genetic background. The two G12P[4] strains (1.9%) were associated with distinct genetic backbones: Wa-like and DS-1-like. The phylogenetic analysis revealed the circulation of lineages G1-I, G2-IV, G3-III, G8-I and G12-III, and P[4]-V and P[8]-III of the VP7 and VP4 genes, respectively. Conserved clustering pattern and low genetic diversity were observed regarding VP1-VP3 and VP6, as well as NSP1-5 segments. We identified the same RVA circulation pattern reported in other Brazilian regions in the period of 2010-2016, suggesting that rural and low-income areas may not have a different RVA genotypic distribution compared to other parts of the country. The unique presentation of whole-genome data of RVA strains detected in the Tocantins State provides a baseline for monitoring variations in the genetic composition of RVA in this area.

OBJECTIVES: Our objective was to analyze, in a population treated for hepatitis C infection at a tertiary care treatment unit, the prevalence of comorbidities and extrahepatic manifestations, the range and degree of the clinical complexity and the associations between advanced liver disease and clinical variables. METHODS: Medical records from chronically infected hepatitis C patients seen at a dedicated treatment facility for complex cases in the Infectious Diseases Division of Hospital das Clínicas in Brazil were analyzed. Clinical complexity was defined as the presence of one or more of the following conditions: advanced liver disease (Metavir score F3 or F4 and/or clinical manifestations or ultrasound/endoscopy findings consistent with cirrhosis) or hepatocellular carcinoma and/or 3 or more extrahepatic manifestations and/or comorbidities concomitantly. RESULTS: Among the 1574 patients analyzed, only 41% met the definition of being clinically complex. Cirrhosis or hepatocarcinoma was identified in 22.2% and 1.8% of patients, respectively. According to multiple logistic regression analysis, male sex (p=0.007), age>40 years (p<0.001) and the presence of metabolic syndrome (p=0.008) were independently associated with advanced liver disease. CONCLUSION: The majority of patients did not meet the criteria for admittance to this specialized tertiary service, reinforcing the need to reevaluate public health policies. Enhanced utilization of existing basic and intermediate complexity units for the management of less complex hepatitis C cases could improve care and lower costs.