A Nationally Coordinated Laboratory System for Human Avian Influenza A (H5N1) in Thailand: Program Design, Analysis, and Evaluation

Abstract

The NCLS exemplifies a systematic approach to national surveillance for avian influenza A (H5N1). This NCLS program in Thailand serves as a model for human avian influenza (H5N1) preparedness that can be adopted or modified for use in other countries.

A Comparison of Clinical and Epidemiological Characteristics of Fatal Human Infections with H5N1 and Human Influenza Viruses in Thailand, 2004–2006

“…Data were analyzed using STATA (Version 8, College Station, TX) statistical software. Disaggregated clinical and epidemiological data for 17 of 25 H5N1 cases have been previously reported, however, the data presented here represent a new abstraction and a complete analysis of all 25 H5N1 cases detected in Thailand during the study period [2], [5], [6]. The statistical analysis consisted of the following three parts: 1) a comparison of demographic characteristics and high-risk exposures between cases testing positive for H5N1 versus a sample of all human influenza cases; 2) a comparison of clinical characteristics associated with fatal and non-fatal outcome among H5N1 cases; and 3) a comparison of clinical characteristics of fatal H5N1 versus fatal human influenza cases.…”

“…NAIS was established by Thailand's Ministry of Public Health (MOPH) in December 2003 following Thailand's first outbreaks of influenza A(H5N1) among poultry. Laboratory and epidemiological response components of the surveillance system have been previously described [1], [2], [3]. Surveillance for H5N1 cases was healthcare facility-based, involving all public and private hospitals, outpatient departments, and freestanding clinics in all provinces of the country.…”

“…Report of a suspect H5N1 case to public health authorities triggered an epidemiological investigation and a public health response by district, provincial, and or regional Surveillance and Rapid Response Teams (SRRTs) [1]. Respiratory specimens collected from suspect H5N1 cases—consisting of nasopharyngeal swabs, throats swabs, or sputum from endotracheal suction—were tested by a network of 13 regional laboratories and one central laboratory overseen by the Thailand National Institute of Health (Thailand NIH); diagnostic virologic testing consisted of conventional or real-time reverse-transcriptase polymerase chain reaction (RT-PCR) for highly pathogenic avian influenza A(H5N1) and human influenza viruses (A(H1N1), A(H3N2), and type B) [2]. Results of virologic testing were relayed back to the treating clinicians and public health authorities via direct notification and through an online web-based reporting system.…”

“…As part of Thailand's public health response, the National Avian Influenza Surveillance (NAIS) system was established to detect, investigate, and control H5N1 cases [1], [2]. In the setting of heightened concern over the potential emergence of a widespread influenza A(H5N1) epidemic among humans, many thousands of suspect H5N1 cases were investigated and 25 H5N1 cases were eventually confirmed; in addition, 18% of suspect H5N1 cases tested positive for a human (seasonal) influenza virus infection (hereafter referred to as human influenza cases) [3].…”

Severe Human Influenza Infections in Thailand: Oseltamivir Treatment and Risk Factors for Fatal Outcome

“…If patients had risk factors or the physician suspected avian influenza infection, nasopharyngeal swabs, throat swabs or secretions from endotracheal suctions were collected from patients and tested by RT-PCR for influenza A subtypes H1, H3, H5 and influenza Type B at the Thailand National Institute of Health (NIH) laboratory in Bangkok or at several regional NIH network laboratories [12]. All H5N1 positive specimens and those from rapidly progressive or fatal human influenza cases were confirmed at the central NIH laboratory.…”