Epidemic infectious gastrointestinal illness aboard U.S. Navy ships deployed to the Middle East during peacetime operations--2000-2001

Abstract

Background: Infectious gastrointestinal illness (IGI) outbreaks have been reported in U.S. Navy ships and could potentially have an adverse mission impact. Studies to date have been anecdotal.

Methods: We conducted a retrospective analysis of weekly reported disease and non-battle injury health data collected in 2000-2001 from 44 U.S. Navy ships while sailing in the 5th Fleet (Persian Gulf and nearby seas).

Results: During this period, 11 possible IGI outbreaks were identified. Overall, we found 3.3 outbreaks per 100 ship-weeks, a mean outbreak duration of 4.4 weeks, and a mean cumulative ship population attack rate of 3.6%. Morbidity, represented by days lost due to personnel being placed on sick-in-quarters status, was higher during outbreak weeks compared to non-outbreak weeks (p = 0.002). No clear seasonal distribution was identified.

Conclusion: Explosive outbreaks due to viruses and bacteria with the potential of incapacitating large proportions of the crew raise serious concerns of mission impact and military readiness.

Figure 1

Possible infectious GI outbreaks among ships deployed to the Persian Gulf AOR during October 2000 – September 2001. Destroyer Aircraft Carrier Amphibious Assault/Combat Support