Review article

Impact of infectious diseases on war☆

Vaccination plays a key role in the prevention of the infectious diseases, which the armed forces are exposed to during overseas deployments. Historically, the French military health service have always contributed greatly to progress in vaccination. The military immunization schedule has often been used as a model for the national schedule. It is a powerful tool, which is constantly evolving to take into account the risks of infection inherent in deployment and to include new scientific data, while still remaining aware of the limitations of vaccination from an individual and collective standpoint. In the current context of increasingly fast emergence or re-emergence of pathogens with a high epidemic potential, developing preventive medical measures is more necessary than ever before, and the French military health service is actively participating.

The armed conflict in Colombia (FARC rebels vs. Colombian government) is one of the oldest in Western countries, including thousands of deaths, massacres and terrible living conditions for those who have perceived it closely. It was until 2016 that this conflict reached a historic and longed for ceasefire agreement. This new social condition brought many benefits for the country, since agriculture has been renewed and trade and tourism have been activated in many regions that were affected by this senseless war. However, it should be noted that this reintegration and migration of individuals outside the law, and even of the same military of the National Army that were in combat, involved in wild cycles of insects and pathogens transmitting diseases to rural areas where mosquitoes also circulate; can have an impact on National Health Systems and plans for the control and prevention of vector-borne diseases, as they could cause outbreaks where infection rates are increased mainly in the normalization zones (“zonas veredales”) where FARC numbers will be concentrated. This may have an effect on the diversity of causal agents of these diseases. Then, it would be of great importance to have an adequate management plan and to keep in mind the costs that must be assumed by the government for the diagnosis, treatment and surveillance of people who may be affected.

Vibrio cholerae causes cholera and is the leading cause of diarrhea in developing countries, highlighting the need for the development of new treatment strategies to combat this disease agent. While exploring the possibility of using zinc oxide (ZnO) nanoparticles (NPs) in cholera treatment, we previously found that ZnO NPs reduce fluid accumulation in mouse ileum induced by the cholera toxin (CT) protein. To uncover the mechanism of action of ZnO NPs on CT activity, here we used classical (O395) and El Tor (C6706) V. cholerae biotypes in growth and biochemical assays. We found that a ZnO NP concentration of 10 μg/ml did not affect the growth rates of these two strains, nor did we observe that ZnO NPs reduce the expression levels of CT mRNA and protein. It was observed that ZnO NPs form a complex with CT, appear to disrupt the CT secondary structure, and block its interaction with the GM1 ganglioside receptor in the outer leaflet of the plasma membrane in intestinal (HT-29) cells and thereby reduce CT uptake into the cells. In the range of 2.5–10 μg/ml, ZnO NPs exhibited no cytotoxicity on kidney (HEK293) and HT-29 cells. We conclude that ZnO NPs prevent the first step in the translocation of cholera toxin into intestinal epithelial cells without exerting measurable toxic effects on HEK293 and HT-29 cells.

Infectious diseases are a frequent cause of morbidity in French troops deployed abroad. They are usually minor in severity and managed by field practitioners. We aimed to describe the etiological spectrum of travel-related infections in French soldiers evacuated to a level 4 military treatment facility.

We evaluated the diagnoses of all service members who were medically evacuated from abroad to our infectious diseases department from January 1, 2004 to October 30, 2013.

One hundred and twenty five cases, median age 32 years were referred, 117 (94%) were male and 78 (62%) were from the Army. Main areas of deployment were Africa in 80 cases (64%), Afghanistan in 15 cases (12%), and French Guiana in 10 cases (8%). Median time between initial consultation and hospitalization in the reference center was 5 days (IQ 2–7 d). Thirty (24%) immediate aeromedical evacuations were carried out. The top five diagnoses were Plasmodium falciparum malaria (30), fever of unknown origin (15), cerebro-meningeal infections (10), invasive amebiasis (9), and HIV primary infections (9). Thirteen individuals were admitted in ICU. No death was recorded.

Infectious diseases were a rare of cause of medevac. Most of them were preventable. Lethal etiologies were represented by malaria and cerebro-meningeal infections.

Military personnel in operations have always paid a high toll to infections. In the 21st century some of these diseases still cause outbreaks with significant morbidity and impact on deployments. The new configuration of the French Armed Forces requires the permanent preparedness of deployable units. During deployments, soldiers are at least exposed to the infectious diseases that are observed in travellers, but with a potentially severe impact for the combatting strengths and a risk for cancelation or failure of the operational durability. The most common disabling infections during military deployments are faeco-oral transmitted diseases including diarrhoea. Preventing infectious diseases during deployments is of great concern and the French medical service has established a strategy based on different components; risk assessment and preparation, immunizations, protective measures and chemoprophylaxis, health education, health surveillance, outbreak investigations and medical tracking. In this review, the authors present the context of deployment of the French Armed Forces, the main health risks they are exposed to and develop the key points of the force health protection strategy, focused on infections related to military deployments.