Hepatitis B virus (HBV) remains a major public health issue worldwide. In 2022, the World Health Organization (WHO) estimated that approximately 254 million people were living with chronic hepatitis B, with 1.2 million new infections each year. This infection causes nearly 1.1 million annual deaths, mainly due to severe complications such as cirrhosis or hepatocellular carcinoma [1] .

Côte d’Ivoire is classified as a high-endemicity zone, with an estimated prevalence between 8% and 12% [2] - [4] . Military personnel are among the at-risk groups due to their frequent mobility, young age (often sexually active), and involvement in potentially risky missions (e.g., caring for the wounded, exposure to blood, transfusions, etc.).

Despite this high exposure, few studies have focused on the epidemiology of HBV in this specific population in Côte d’Ivoire [5] . This study, therefore, aims to determine the seroprevalence of hepatitis B virus infection and to identify associated risk factors among members of the National Armed Forces of Côte d’Ivoire stationed in the Bouaké region.

This was a single-center, cross-sectional, descriptive, and analytical study. It was conducted from September 2021 to March 2022 at the National School for Active Non-Commissioned Officers (ENSOA) in Bouaké. Included were all military or gendarmerie personnel stationed in a unit of the Armed Forces of Côte d’Ivoire in Bouaké who gave informed consent. Civilian personnel and non-consenting military personnel were excluded.

The study involved 227 military personnel from the Bouaké military region. The average age was 32.2 years (range: 20 to 54). The participants included 10 enlisted soldiers, 214 non-commissioned officers, and 3 officers. The sex ratio was 7.4. Soldiers with less than 10 years of experience were most represented (65.6%), and 79% were single. Eleven participants (4.85%) reported full vaccination. HBs antigen was positive in 12 soldiers (5.29%), and anti-HBc antibodies were positive in 43.6% of cases ( Table 1 ).

Significant factors associated with HBsAg positivity included age over 30 (p = 0.032), being single (p = 0.027), more than 10 years of service, and having completed missions inside the country ( Table 2 ).

This study aimed to evaluate HBV prevalence and associated risk factors in a military population in Côte d’Ivoire. Military personnel are typically considered at-risk for viral infections due to mobility, potential blood exposure, and risky sexual behavior. Our study population consisted mainly of young men, similar to findings from studies conducted in Benin and Senegal [6] [7] .

Vaccination coverage remains low: only 4.85% reported receiving the full three-dose vaccine regimen. This confirms results from Diop in Senegal and Assi in Côte d’Ivoire, who also reported low vaccination rates [5] [6] . In Côte d’Ivoire, the lack of a national policy for vaccinating at-risk personnel likely explains this low coverage. Consequently, hepatitis B vaccination in high-risk professions depends on individual initiative [5] . In countries with such policies, like the United States, more than 65% of firefighters are vaccinated against hepatitis B [8] . Approximately 40% of participants had anti-HBc antibodies, indicating prior exposure to HBV, as is common in most African high-endemic countries [9] [10] .

The 5.29% HBsAg prevalence found in our study is similar to that of other occupational categories in Côte d’Ivoire [11] , the region [12] , and some developing countries [13] [14] . However, it is lower than previously reported rates among Ivorian soldiers in 2008 and 2012 (15%) [5] [15] . This may be due to the younger age of the population studied, who could have benefited from infant vaccination introduced in 2001 [16] . Indeed, 52.4% of the soldiers in our study were under 30. Further studies could assess protective antibodies (anti-HBs) to evaluate the real effect of vaccination in this group.

Other factors significantly associated with HBsAg positivity were over 10 years of service, participation in missions, and being single. These findings show that the military profession remains at risk for HBV infection. Risky behaviors like unprotected sex, sharing sharp objects, and blood transfusion were also linked to HBV infection in other regional studies [6] [7] [17] [18] .

This study had some limitations. Only soldiers who gave informed consent were included, possibly introducing selection bias. As a cross-sectional study, it cannot establish causality between risk factors and HBV infection. Furthermore, only a univariate analysis was conducted, which did not account for potential confounding factors. Nevertheless, it provides an overview of hepatitis B among soldiers in Bouaké and highlights determinants that may contribute to infection.

Hepatitis B is relatively frequent in the Bouaké military region, with a prevalence of 5.23%. It predominantly affects soldiers over 30, single, with more than 10 years of service, and who have completed missions within the country. These factors should be considered in designing better HBV screening and prevention strategies for the armed forces.