A nationally coordinated laboratory system for human avian influenza A (H5N1) in Thailand: program design, analysis, and evaluation.
BACKGROUND
The first phase of national surveillance for avian influenza (H5N1) human disease in Thailand occurred over a 4-month period that began on 1 December 2003. Subsequently, a nationally coordinated laboratory system (NCLS) for avian influenza (H5N1) was created to assess population-based surveillance, specimen procurement, case detection, and reporting at the national level.


METHODS
We conducted a pre- and postintervention study to evaluate the NCLS designed during the 6-week interval from 1 April through 15 May 2004. During the pre-NCLS period (1 December 2003 through 31 March 2004), 12 cases of human avian influenza (H5N1) were confirmed. During the post-NCLS period (16 May 2004 through 31 December 2006), interventions were implemented for human avian influenza (H5N1) surveillance, case detection, and expedited, computer-based reporting.


RESULTS
During the pre- and post-NCLS periods, 777 (85%) of 915 and 10,434 (95%) of 11,042 clinical respiratory specimens, respectively, were adequate for confirmatory testing (P<.001), the median time from procurement to results decreased from 17 days (range, 14-24 days) to 1.8 days (range, 0.25-4 days; P<.001), and the duration of specimen shipment decreased from 46.5 h to 21.1 h (P<.001). Thirteen cases of avian influenza (H5N1) were detected during the 31-month postintervention period. H5N1 reverse-transcriptase polymerase chain reaction and real-time reverse-transcriptase polymerase chain reaction sensitivity was 100% and specificity was 99.8%.


CONCLUSIONS
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.
Kitphati
Rungrueng
R
Department of Medical Sciences, Thai National Institute of Health, Nonthaburi.
Apisarnthanarak
Anucha
A
Chittaganpitch
Malinee
M
Tawatsupha
Pranee
P
Auwanit
Wattana
W
Puthavathana
Pilaipan
P
Auewarakul
Prasert
P
Uiprasertkul
Mongkol
M
Mundy
Linda M
LM
Sawanpanyalert
Pathom
P
D000818:Animals; D001717:Birds / Q000821:virology; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000235:genetics / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D007251:Influenza, Human / Q000175:diagnosis / Q000453:epidemiology / Q000821:virology*; D007753:Laboratories; D011159:Population Surveillance / Q000379:methods; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013785:Thailand / Q000453:epidemiology