The prevalence of recurrent herpes labialis during an army hot weather exercise.

A survey was performed on 1,062 of 2,500 (42%) Army personnel participating in a desert training exercise at Fort Irwin, California, in September 1983. The prevalence of recurrent herpes labialis (RHL) and chapped lips was observed during the third week of a four-week training period. Complexion, sex, lip protectant use, age, and time spent outdoors were obtained by observation and interview. Recurrent herpes labialis was found in 46 subjects (4%). Stratified analysis and stepwise logistic regression were used to identify risk factors associated with RHL and to determine the prevalence odds ratios (POR). Risk factors with statistically significant associations with RHL were lip protectant use (POR = 0.19), chapped lips (POR = 2.87), being female (POR = 5.00), and light complexion (POR = 2.48). These findings strongly support the use of lip protectants during prolonged exposure to hot, dry climates as a prophylaxis against recurrent herpes labialis. Additional studies should focus on excitatory factors of RHL; and clinical trials of the efficacy of the lip protectants to protect against RHL and chapped lips should be undertaken.