Identification of a Orthohantavirus strain by clinical metagenomics in Brazil.

We describe a case of a 33-year-old male presented with fever, myalgia, nausea, and asthenia for six days. The patient lived in a rural area. Initial hypotheses included arbovirus infection, viral hepatitis, and Lyme disease.

Associations of SARS-CoV-2 cycle threshold values with age, gender, sample collection setting, and pandemic period.

Cycle threshold (Ct) values in COVID-19 reverse-transcription polymerase chain reaction (RT-PCR) tests estimate the viral load in biological samples. Studies have investigated variables associated with SARS-CoV-2 viral load, aiming to identify factors associated with higher transmissibility. Using the results from tests performed between May/2020-July/2022 obtained from the database of a referent hospital in Sao Paulo, Brazil, we investigated associations between Ct values and patient's age, gender, sample collection setting and pandemic period according to the predominant SARS-CoV-2 variant locally.

Longer-term effectiveness of a heterologous coronavirus disease 2019 (COVID-19) vaccine booster in healthcare workers in Brazil.

Objective: To compare the long-term vaccine effectiveness between those receiving viral vector [Oxford-AstraZeneca (ChAdOx1)] or inactivated viral (CoronaVac) primary series (2 doses) and those who received an mRNA booster (Pfizer/BioNTech) (the third dose) among healthcare workers (HCWs).

Methods: We conducted a retrospective cohort study among HCWs (aged ≥18 years) in Brazil from January 2021 to July 2022. To assess the variation in the effectiveness of booster dose over time, we estimated the effectiveness rate by taking the log risk ratio as a function of time.

Risk factors for long coronavirus disease 2019 (long COVID) among healthcare personnel, Brazil, 2020-2022.

Objective: To determine risk factors for the development of long coronavirus disease 2019 (COVID-19) in healthcare personnel (HCP).

Methods: We conducted a case-control study among HCP who had confirmed symptomatic COVID-19 working in a Brazilian healthcare system between March 1, 2020, and July 15, 2022. Cases were defined as those having long COVID according to the Centers for Disease Control and Prevention definition.

Characterization of primary direct-acting antiviral (DAA) drugs resistance mutations in NS5A/NS5B regions of hepatitis C virus with genotype 1a and 1b from patients with chronic hepatitis.

The Hepatitis C virus (HCV) infection is a public health problem. The high level of HCV replication and its lack of post-transcriptional correction mechanisms results in the emergence of viral variants and the difficulty in determining polymorphisms and variants that contain the substitutions associated with resistance towards new antivirals. The main focus of this study was to map the NS5A and NS5B polymorphisms and resistance mutations to new antiviral drugs in HCV strains genotype 1 from patients with chronic hepatitis C infection.

Long term persistence of coronavirus SARS-CoV-2 infection.

During the COVID-19 pandemic, a case of a long-term persistence of SARS-CoV-2 infection (from March 26 to May 20, 2020) was identified at a private hospital in São Paulo, SP, Brazil. The long-term positivity for SARS-CoV-2 in reverse transcriptase polymerase chain reaction tests of a patient diagnosed with COVID-19 suggests, at least part of patients who recovered, may still carry and transmit the SARS-CoV-2 virus. This fact emphasizes the importance of having at least two negative reverse transcriptase polymerase chain reaction test results for SARS-CoV-2.

Prevalence and Pattern of Resistance in NS5A/NS5B in Hepatitis C Chronic Patients Genotype 3 Examined at a Public Health Laboratory in the State of São Paulo, Brazil.

Purpose: Globally, it is estimated that 71 million people are chronically infected with hepatitis C, and 10-20% of these will develop cirrhosis and hepatocellular carcinoma. The development of new direct-acting antiviral (DAA) drugs has contributed to sustained virological response (SVR), eliminating the infection and achieving cure of chronic hepatitis C. However, treated patients can develop HCV resistance to DAAs, which can contribute to the failure of treatment.

SARS-CoV-2 isolation from the first reported patients in Brazil and establishment of a coordinated task network.

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was confirmed in Brazil in February 2020, the first cases were followed by an increase in the number of cases throughout the country, resulting in an important public health crisis that requires fast and coordinated responses.

Objectives: The objective of this work is to describe the isolation and propagation properties of SARS-CoV-2 isolates from the first confirmed cases of coronavirus disease 2019 (COVID-19) in Brazil.

Methods: After diagnosis in patients that returned from Italy to the São Paulo city in late February by RT-PCR, SARS-CoV-2 isolates were obtained in cell cultures and characterised by full genome sequencing, electron microscopy and in vitro replication properties.

Lower cost alternatives for molecular diagnosis of COVID-19: conventional RT-PCR and SYBR Green-based RT-qPCR.

In March 2020, WHO declared a pandemic state due to SARS-CoV-2 having spread. TaqMan-based real-time RT-qPCR is currently the gold standard for COVID-19 diagnosis. However, it is a high-cost assay, inaccessible for the majority of laboratories around the world, making it difficult to diagnose on a large scale.

Prevalence of resistance-associated substitutions to direct-acting antiviral agents in hemodialysis and renal transplant patients infected with hepatitis C virus.

Background: Direct-acting antiviral agents (DAAs) permit the use of interferon (IFN)-free regimens to treat hepatitis C (HCV) in patients with chronic kidney disease (CKD) on hemo-dialysis (HD) or renal transplant (RTx) recipients, with excellent response rates and safety. However, the occurrence of basal or therapy-induced resistance-associated substitutions (RASs) to DAAs can result in treatment failure. The aim of this study was to estimate the prevalence of RASs to NS3A, NS5A and NS5B inhibitors, and particularly the Q80K polymorphism, in CKD patients on HD and RTx recipients infected with HCV.

An Outbreak of Human Parvovirus B19 Hidden by Dengue Fever.

Background: Seasonal outbreaks of dengue often result in hundreds of dengue-suspected cases where a clinical diagnosis cannot be confirmed. Usually, during large outbreaks of dengue and other pathogens that can cause acute febrile illnesses, the search for secondary pathogens with similar disease outcomes is rare.

Methods: Using total RNA sequencing and targeted diagnostic assays, we discovered an outbreak of parvovirus B19 in dengue-suspected patients that occurred from November 2013 to February 2014.

Prevalence of naturally occurring amino acid substitutions associated with resistance to hepatitis C virus NS3/NS4A protease inhibitors in São Paulo state.

Hepatitis C (HCV)-infected patients are treated with direct-acting antiviral agents (DAAs) in highly effective, well-tolerated, all-oral regimens. However, naturally occurring resistance-associated amino acid substitutions (RASs) may be selected during treatment. This study aimed to screen naturally occurring RASs NS3/NS4A inhibitors (PIs).

Ferritin light chain gene mutations in two Brazilian families with hereditary hyperferritinemia-cataract syndrome.

Hereditary hyperferritinemia-cataract syndrome is an autosomal dominant genetic disorder associated with mutations in the 5'UTR region of the ferritin light chain gene. These mutations cause the ferritin levels to increase even in the absence of iron overload. Patients also develop bilateral cataract early due to accumulation of ferritin in the lens, and many are misdiagnosed as having hemochromatosis and thus not properly treated.

Hepatitis C among blood donors: cascade of care and predictors of loss to follow-up.

Objective: To investigate the HCV cascade of care and to identify the factors associated with loss or absence to follow-up of patients identified as infected with hepatitis C through blood donation.

Methods: Blood donors from 1994 to 2012, identified with positive anti- HCV by enzyme immunoassay and immunoblot tests were invited to participate in the study, through letters or phone calls. Patients who agreed to participate were interviewed and their blood samples were collected for further testing.

Persistence of Zika Virus in Breast Milk after Infection in Late Stage of Pregnancy.

We detected Zika virus in breast milk of a woman in Brazil infected with the virus during the 36th week of pregnancy. Virus was detected 33 days after onset of signs and symptoms and 9 days after delivery. No abnormalities were found during fetal assessment or after birth of the infant.

Natural occurrence of NS5B inhibitor resistance-associated variants in Brazilian patients infected with HCV or HCV and HIV.

Resistance-associated variants (RAVs) represent a challenge to the success of new HCV therapies. The aim of this study was to describe the prevalence of naturally occurring NS5B RAVs in Brazilian direct acting antivirals (DAA)-naïve patients infected with HCV genotype 1, or co-infected with HIV. Patient enrollment and sample collection were performed between 2011 and 2013.

Interferon lambda and hepatitis C virus core protein polymorphisms associated with liver cancer.

Background: Hepatitis C virus (HCV) infection is often persistent and gradually advances from chronic hepatitis to liver cirrhosis and hepatocellular carcinoma (HCC). Worldwide, hepatocellular carcinoma is the fifth most common neoplasm.

Method Of Study: the Interferon lambda (IFNL) polymorphisms genotypes (rs8099917, rs12979860 and rs12980275) and the presence of mutations in HCV core protein were analyzed in 59 patients with HCC, and also in 50 cirrhotic patients (without HCC).

Increased hepatic expression of miRNA-122 in patients infected with HCV genotype 3.

Hepatitis C virus (HCV) infection affects approximately 3 % of the world population. HCV targets hepatic tissue, and most infected patients develop a chronic infection. Currently, studies have demonstrated an association between HCV-RNA replication and miR-122, the most abundant microRNA in the liver.

Full-length genomic sequence of hepatitis B virus genotype C2 isolated from a native Brazilian patient.

The hepatitis B virus (HBV) is among the leading causes of chronic hepatitis, cirrhosis and hepatocellular carcinoma. In Brazil, genotype A is the most frequent, followed by genotypes D and F. Genotypes B and C are found in Brazil exclusively among Asian patients and their descendants.