Viral agents responsible for febrile respiratory illnesses among military recruits training in tropical Singapore.
BACKGROUND
Military personnel are highly susceptible to febrile respiratory illnesses (FRI), likely due to crowding, stress and other risk factors present in the military environment.


OBJECTIVE
Our objective was to investigate the viral etiological agents responsible for FRI among military recruits training in a tropical climate in Singapore.


METHODS
From March 2006 through April 2007, a total of 1354 oropharyngeal (throat) swabs were collected from military recruits who reported sick with an oral temperature of > or =38 degrees C and a cough and/or sore throat. Real-time polymerase chain reaction (PCR) was used to assay for the presence of influenza A and B viruses and adenoviruses (H-AdV), and conventional PCR used for the remaining respiratory viruses in all specimens.


RESULTS
Influenza A virus was the dominant infection with a laboratory-confirmed incidence of 24% (326/1354) and a predominance of the H3N2 subtype. The temporal pattern for influenza A virus infections coincided with the nation-wide pattern in the civilian community. Detection rates of 12% (159/1354) and 2.7% (5/1354) were obtained for influenza B virus and other respiratory viruses, respectively.


CONCLUSIONS
The laboratory findings identified influenza A virus as the primary causative viral agent for FRI in the Singapore military, in strong contrast to findings from temperate countries and countries where recruits are often vaccinated for influenza. Our results suggest that influenza vaccination should be considered as a requirement to reduce the incidence of influenza infections. This is the first report describing respiratory infections in a tropical military setting, in a developed country in Asia.
Seah
Shirley Gek-Kheng
SG
Detection and Diagnostics Laboratory, DSO National Laboratories, Singapore.
Lim
Elizabeth Ai-Sim
EA
Kok-Yong
Seng
S
Liaw
Jasper Chin-Wen
JC
Lee
Vernon
V
Kammerer
Peter
P
Metzgar
David
D
Russell
Kevin L
KL
Tan
Boon-Huan
BH
D000293:Adolescent; D000328:Adult; D006801:Humans; D008297:Male; D008889:Military Personnel; D009960:Oropharynx / Q000821:virology; D016133:Polymerase Chain Reaction / Q000379:methods; D015995:Prevalence; D012141:Respiratory Tract Infections / Q000821:virology*; D012846:Singapore; D014777:Virus Diseases / Q000821:virology*; D014780:Viruses / Q000145:classification* / Q000302:isolation & purification*; D055815:Young Adult