Weekly oral azithromycin as prophylaxis for agents causing acute respiratory disease

Area of Science:

• Military Medicine
• Infectious Disease Prevention
• Pharmacology

Background:

• Benzathine penicillin G (BPG) has been the standard intramuscular injection for controlling military respiratory disease outbreaks since the 1950s.
• There is a need for alternative prophylactic treatments due to potential limitations or side effects of BPG.

Purpose of the Study:

• To evaluate oral azithromycin as an alternative prophylaxis to BPG for preventing respiratory infections in high-risk military trainees.
• To compare the efficacy and side effect profile of oral azithromycin against BPG and a no-treatment control group.

Main Methods:

• A randomized field trial involving 1,016 male U.S. Marine trainee volunteers.
• Serological tests on pretraining and posttraining sera (63 days apart) to assess acute respiratory infection.
• Comparison of infection rates for Streptococcus pyogenes, Streptococcus pneumoniae, Mycoplasma pneumoniae, and Chlamydia pneumoniae across treatment groups.

Main Results:

• Oral azithromycin demonstrated significant efficacy in preventing infections: Streptococcus pyogenes (84%), Streptococcus pneumoniae (80%), Mycoplasma pneumoniae (64%), and Chlamydia pneumoniae (58%).
• The azithromycin group reported fewer side effects and reduced respiratory symptoms compared to both BPG and no-treatment groups.
• Azithromycin outperformed BPG in preventing the studied bacterial and atypical pneumoniae infections.

Conclusions:

• Oral azithromycin is a safe and effective alternative prophylaxis to BPG for military populations at risk of respiratory infections.
• The study supports the use of azithromycin for preventing common respiratory pathogens in demanding military environments.
• Further research could explore long-term efficacy and broader applicability in diverse military settings.