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

Abstract

BackgroundThe 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.MethodsWe included 196 symptomatic children and their 192 asymptomatic caregivers, 70 symptomatic and 95 asymptomatic HCWs, 43 samples from symptomatic HIV‐positive outpatients, and 100 samples of asymptomatic HIV patients in the period of 2009‐2013.ResultsRSV infection was detected in 10.1% (70/696) of samples, 4.4% (17/387) of asymptomatic patients, and 17.1% (53/309) from symptomatic patients. (P < .0001). The VL of symptomatic patients (4.7 log copies/mL) was significantly higher compared to asymptomatic patients (2.3 log copies/mL). RSV detection among asymptomatic caregivers (6.8%; 13/192) was significantly higher compared to other asymptomatic adults, HIV and HCWs (2.0%; 4/195; P = .0252). A close contact with an infected child at home was an important risk to RSV acquisition [OR 22.6 (95% CI 4.8‐106.7)]. Children who possibly transmitted the virus to their asymptomatic contacts had significantly higher viral load than children who probably did not transmit (P < .0001).ConclusionsAccording to our results, it is important to know if people circulating inside the hospital have close contact with acute respiratory infected children.

Influenza and respiratory syncytial virus screening for the detection of asymptomatically infected patients in hematology and oncology

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Transmission of Acute Respiratory Infections in a City: Agent-Based Approach

“…Для гриппа болезнь может с вероятностью p = 0.16 протекать в бессимптомной форме [47], тогда как для остальных видов вероятность бессимптомной формы равна 0.25 [48]. Считаем, что средняя вирусная нагрузка при бессимптомной инфекции в 2 раза ниже, чем при клинически выраженной инфекции [49,50]. Если же болезнь протекает с выраженными симптомами, то агент может самоизолироваться дома с определенной вероятностью до конца болезни (табл.…”

Transmission and prevention of acute viral respiratory tract infections in hospitals

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