Prevalence of hepatitis C in U.S. Army aircrew: do flaws in the data exist?

Hepatitis C virus (HCV) infection is a rare condition with unknown prevalence in Army aircrew. This is a retrospective serial prevalence study to determine the prevalence of HCV in Army aircrew and discuss whether this reflects the true prevalence rate.

The Aviation Epidemiology Data Registry (AEDR) at the U.S. Army Aeromedical Center was queried by ICD-9-CM codes for cases of hepatitis from January 1988 to October 1999. These records were further reviewed for documented cases of HCV. Case details were extracted and then the data were evaluated.

The prevalence rate in this population is exceedingly low at 0.000087 cases per year averaged over the 12 yr, or 1 case in 11,000 aircrew per year with an average of 24,077 records per year. The total number of cases was 31, with 22 of those involving pilots. Subjects averaged 15.26 yr of military service.

The prevalence of HCV in aircrew is low and is much lower than in the general and military populations. These prevalence rates may be skewed low due to lack of universal reporting method, no screening, and asymptomatic nature of initial infection. Conversely, the prevalence may be accurate due to high fitness levels, population motivation, and required healthcare visits. Current prevalence rates do not support a need for universal screening, but the cost of case detection in lost training dollars and experience is significant. A definitive study would assess the true prevalence rate and determine if screening in this population is warranted.