Clarice Neves Camargo

Respiratory viral coinfection among hospitalized patients with H1N1 2009 during the first pandemic wave in Brazil

Abstract Influenza A coinfections with other respiratory viruses were investigated in 25.8% (41/159) of the samples from patients hospitalized in 2009 at our University Hospital. Out of the 41 influenza A cases, nine cases (21.9%) were coinfected with other viruses, with a similar frequency among children and adults (p=0.47), and seasonal influenza cases were more prevalent than H1N1 2009 influenza virus. Adenovirus was the most frequently detected (4/9) among coinfected cases. Coinfection was not associated with higher morbidity or mortality (p=0.75).

Human adenovirus detection among immunocompetent and immunocompromised patients presenting acute respiratory infection

INTRODUCTION Human adenoviruses (HAdV) play an important role in the aetiology of severe acute lower respiratory infection, especially in immunocompromised individuals. The aim of the present study was to detect HAdV using two different methods, direct fluorescence assay (DFA) and nested polymerase chain reaction (nested PCR), in samples collected from patients with acute groups from 2001 to 2010: 139 adult emergency room patients (ERP); 205 health care workers (HCW); 69 renal transplant outpatients(RTO); and 230 patients in a haematopoietic stem cell transplantation program (HSCT). RESULTS Adenovirus was detected in 13.2% of the 643 patients tested by DFA and/or PCR: 6/139 (4.3%) adults in the ERP group, 7/205 (3.4%) in the HCW group, 4/69 (5.8%) in the RTO group and 68/230 (29.5%) in the HSCT patient group. Nested PCR had a higher detection rate (10%) compared with the DFA test (3.8%) (p<0.001). HSCT patients exhibited a significantly higher rate of HAdV infection. CONCLUSIONS The adenovirus detection rate of the nested PCR assay was higher than that of the DFA test. However, the use of molecular methods in routine diagnostic laboratory work should be evaluated based on the specific circumstances of individual health services.

Surveillance of influenza A H1N1 2009 among school children during 2009 and 2010 in São Paulo, Brazil

INTRODUCTION Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (< 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009-2010) in São Paulo, Brazil. METHODS Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months - 12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. RESULTS In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. CONCLUSIONS Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.

Human rhinovirus infections in symptomatic and asymptomatic subjects

The role of rhinovirus asymptomatic infections in the transmission among close contacts subjects is unknown. We tested health care workers, a pair of one child and a family member and immunocompromised patients (n =191). HRV were detected on 22.9% symptomatic and 3.6% asymptomatic cases suggesting lower transmission among contacts.

Casos confirmados de influenza em pacientes hospitalizados com suspeita de infecção por influenza A (H1N1) em 2010 em um hospital sentinela na cidade de São Paulo

In 2010, 96 patients suspected of being infected with the influenza A (H1N1) virus were hospitalized at the Hospital Sao Paulo, located in the city of Sao Paulo, Brazil. Of those 96 patients, 4 (4.2%) were found to be infected with influenza A virus-3 with influenza A (H1N1) and 1 with seasonal influenza A-and 2 patients (2.1%) were found to be infected with influenza B virus. Most (63.5%) of the suspected cases occurred in children, as did half of the positive cases. The second wave of influenza A (H1N1) infection was weaker in Sao Paulo. The decrease in the number of hospitalizations for H1N1 infection in 2010 might be attributable to vaccination.

Respiratory syncytial virus evaluation among asymptomatic and symptomatic subjects in a university hospital in Sao Paulo, Brazil in the period of 2009 to 2013

The respiratory syncytial virus (RSV) is recognized as an important cause of respiratory tract infections. Immunocompromised patients, healthcare workers (HCWs) and children contacts are at increased risk of acquiring the infection. However, the impact of asymptomatic infection in transmission has not been well studied. Objectives: this study evaluated the frequency and viral load (VL) of RSV in nasal swab samples of individuals with different risk factors for acquiring infection in a university hospital in Sao Paulo, Brazil.

Influenza virus surveillance among young children in São Paulo, Brazil: the impact of vaccination

This study assessed the presence of influenza virus among young children and the coverage of vaccination from 2010 to 2012 in São Paulo, Brazil. Our results demonstrated a lower rate of influenza detection and a predominance of influenza B. A decrease of coverage vaccination through the surveillance periods was observed.