Performance of a Rapid Influenza Test in Children During the H1N1 2009 Influenza A Outbreak

Abstract

WHAT'S KNOWN ON THIS SUBJECT:Sensitivities of RIDTs have varied widely for the diagnosis of seasonal influenza. Few pediatric-specific data are available on RIDT performance for H1N1 2009 influenza A. WHAT THIS STUDY ADDS:To the best of our knowledge, this is the largest series reported to date of a comparison of RIDT performance to 2 reference standards, viral culture and rRT-PCR, for the detection of influenza A H1N1 2009 in respiratory specimens from pediatric patients. abstract OBJECTIVE: To evaluate the performance of a rapid influenza diagnostic test (RIDT) in detecting H1N1 2009 influenza A virus in respiratory samples from pediatric patients in comparison to that of real-time reverse-transcriptase polymerase chain reaction (rRT-PCR) and viral culture.METHODOLOGY. This was a cross-sectional diagnostic-accuracy study conducted at a tertiary care children's hospital. Patients for whom the RIDT (BinaxNOW [Binax, Inc, Portland, ME]), viral culture, and rRT-PCR results were known were included. Sensitivity, specificity, and likelihood ratios (LRs) were calculated. RESULTS:A total of 3030 specimens had RIDT results paired with both rRT-PCR and viral culture results. With rRT-PCR as the reference, overall test sensitivity was 45% (95% confidence interval [CI]: 43.3%-46.3%) and specificity was 98.6% (95% CI: 98.1%-99%). Positive and negative LRs were 32.9 (95% CI: 22.9 -45.4) and 0.56 (95% CI: 0.54 -0.58), respectively. RIDT sensitivity was significantly higher in young infants and children younger than 2 years than in older children. Using viral culture as the reference standard, RIDT sensitivity was 55.5% (95% CI: 51.9%-95.6%) and specificity was 95.6% (95% CI: 95%-96.1%). The positive and negative LRs were 12.6 and 0.47, respectively. CONCLUSIONS:The RIDT had relatively poor sensitivity but excellent specificity in this consecutive series of respiratory specimens obtained from pediatric patients. Although a positive RIDT result was highly accurate in predicting infection with influenza type A H1N1 2009 in children, a negative RIDT result did not preclude a child having H1N1. Therefore, for children at high risk with influenza-like illnesses during high-prevalence periods of influenza, empiric initiation of antiviral therapy should be considered for patients with a negative RIDT result. Commercially available rapid influenza diagnostic tests (RIDTs) offer the advantages of low cost, ease of use, and rapid turnaround time. 6 The RIDTs also have shown consistently high specificity for both seasonal (92%-100%) and H1N1 2009 (86%-100%) influenza A virus detection. [6][7][8][9][10][11][12][13][14][15] However, the sensitivity of these assays has varied considerably for both seasonal influenza viruses (49%-95%) 6-10 and H1N1 2009 influenza A (10%-53%). [11][12][13][14][15] Furthermore, few data exist on the performance of RIDTs for detection of influenza A H1N1 2009 in children, with sensitivities ranging from 42% to 74%, 16,17 and few data exist on the performance of these assays in clinical settings. We present her...

Detection of 2009 pandemic influenza A(H1N1) virus Infection in different age groups by using rapid influenza diagnostic tests

“…This is consistent with other studies 5 , 9 that found RIDT sensitivity to be significantly higher in infants and children younger than 2 years than in older children. Although higher sensitivity in younger age groups has been observed in several studies, 3 , 5 , 8 , 9 most of the study subjects were children aged 17 years or younger. Our study examined a broad age spectrum of patients and found that a significant decrease in RIDT sensitivity was associated with increasing age.…”

“…Previous studies have shown that RIDT sensitivity was correlated with increasing viral titer 2 , 6 , 7 and that higher RIDT sensitivity was found in younger age groups than older groups 3 , 5 , 8 , 9 . However, these studies were conducted either in pediatric patients or with a small sample of older patients.…”

“…While these tests were developed and introduced prior to the emergence of influenza A(H1N1) 2009, clinicians have utilized these tests routinely to identify patients infected with influenza A(H1N1) 2009 and to make treatment decisions for those patients. Although the specificity of RIDTs as compared to real‐time RT‐PCR has been shown to be high (90–100%), substantial variation in testing sensitivity (17·8–76·7%) in detecting influenza A(H1N1) 2009 has been reported 1 , 2 , 3 , 4 , 5 …”

Caracterização da criança com infecção por H1N1 e da intervenção fisioterapêutica: relato de casos em série

“…O método de diagnóstico de referência para infecção pela influenza H1N1 é realizado por meio de cultura viral, porém é necessário um teste de menor custo, prático para uso e com respostas rápidas para detecção da doença 10 . A infecção por H1N1 é uma doença com novas características clínicas, desconforto respiratório de instalação rápida, infiltração de ambos os campos pulmonares, cursando com hipoxemia severa, distúrbios restritivos e mortalidade elevada 1,3 .…”

“…As crianças foram consideradas como um dos grupos de risco, devido à imaturidade do sistema imunoló-gico 3,7,9 , com tempo de transmissão do vírus maior que dos adultos 9 e ocorrência de surtos institucionais em creches e escolas 6 . Pouco se sabe sobre como a circulação do vírus influenza H1N1 afeta a população infantil, uma vez que há escassez de estudos 7,10 . As estratégias de enfrentamento inicial dessa epidemia global foi baseada em medidas de contenção por meio de identificação precoce, tratamento e isolamento de casos e no seguimento de seus contatos próximos 3,6 .…”