Epidemiologic Consultation No. 29-HE-5711-00 Investigation of an Acute Respiratory Disease Outbreak Due to Adenovirus Type 4 Among Recruits Fort Benning, Georgia

摘要

An epidemiological consultation (EPICON) was conducted to investigate an outbreak of acute respiratory disease (ARD) among U.S. Army Infantry trainees at Fort Benning, GA that resulted in the hospitalization of 194 recruits to Martin Army Community Hospital (MACH) between April 23 and May 6, 2000. This outbreak resulted in a ARD admission rate of 2.9% for the week ending April 29, 2000, a six-fold increase over baseline. The average length of stay for all admitted recruits was 2.1 days. All recruits recovered without sequelae; there were no deaths or serious injuries. A case-control study was performed to develop hypotheses regarding the etiology of the outbreak. One unit was chosen for the company. A case was defined as any Infantry trainee who visited a medical facility with a documented fever greater than or equal to 100.4 deg F (38 deg C) and at least on ARD symptom. The case-control study group included 288 individuals; all male. 54 trainees met our case definition and 234 individuals were considered controls. Univariate analysis indicated several variables associated with being an ARD case such as assignment to Company D, young age, white race, a history of smoking 6 months prior to training, 5th week of training, recruit crowding in the barracks, higher environmental temperature, and lack of soap in the barracks. Multivariate analysis revealed only sleeping density and white race with becoming an ARD case with a p < 0.05. Initially, nasal swab quick tests performed on ill recruits were positive for Influenza A/B but additional laboratory data confirmed that adenovirus (AdV) type 4 was the etiologic agent of the outbreak. Areas for improvement, particularly the ventilation systems, were documented. The most effective intervention for avoiding an AdV outbreak is the oral vaccine; unfortunately, the sole manufacturer ceased production in 1996. Until the vaccine is once again available, outbreaks due to AdV in basic training are inevitable.