Hepatitis B virus serological profiles, susceptibility and associated factors among adolescents in a conflict-affected district of Cameroon: a community-based cross-sectional study

Hepatitis B is a virus that attacks the liver, the body's chemical processing plant. Unlike a cold that passes quickly, this virus can hide in the liver for decades, sometimes causing severe damage or cancer later in life. It spreads through contact with infected blood or body fluids, which can happen through unprotected sex, sharing needles, or even from a mother to a child during birth. Fortunately, a safe vaccine exists that teaches the body to fight the virus before it can take hold. In many parts of the world, this vaccine is given to every child, creating a shield that protects entire communities. However, in places where conflict disrupts daily life and healthcare systems, that shield often has holes. When families are forced to flee their homes, they lose access to the clinics that provide vaccines and the information needed to stay safe.

In the South-West region of Cameroon, a sociopolitical crisis has forced thousands of families to leave their homes and seek refuge in safer areas. Among these displaced people are many teenagers, a group that is often overlooked in public health efforts. Researchers from the University of Buea decided to investigate the health of these young people in the Tiko Health District, an area hosting both local residents and those who have been displaced by the conflict. They wanted to know if these adolescents were protected against Hepatitis B, how many were currently infected, and what factors might be putting them at risk. By looking at blood samples and asking detailed questions about their lives, the team built a clear picture of the virus's presence in this vulnerable community.

The researchers gathered 312 teenagers, aged 10 to 19, from four different communities within the district. They selected these participants using a method that ensured a fair representation of the area's population, including both those who had lived there for generations and those who had recently arrived as refugees. Each young person provided a blood sample, which was tested for five different markers. These markers act like a historical record of the body's encounter with the virus. Some markers show if a person is currently infected, others show if they have recovered from a past infection, and some reveal if they have immunity from a vaccine. The team also asked the participants about their family history, their habits, and what they knew about the disease.

The results painted a concerning picture of vulnerability. While the overall rate of infection was found to be 4.8 percent, meaning roughly five out of every hundred teenagers had the virus, the bigger story was about who was unprotected. Nearly 60 percent of the adolescents had no sign of immunity at all. They had never been vaccinated, nor had they survived a past infection to build natural defenses. This left them wide open to catching the virus if they were exposed. Even more striking was the finding that only about 5 percent of the group showed signs of protection specifically from the vaccine. This suggests that many children in this region either missed their shots or the vaccination programs did not reach them effectively. In contrast, about 31 percent had immunity from a past infection, indicating that the virus has been circulating in the community for some time, infecting children who then fought it off on their own.

The study also uncovered specific factors that made infection much more likely. The most powerful predictor was displacement status. Adolescents who had been forced to leave their homes were more than ten times as likely to be infected as those who had stayed in their original communities. This dramatic difference likely stems from the chaos of displacement: crowded living conditions, a lack of access to healthcare, and the interruption of vaccination schedules. Family history also played a major role; teenagers who knew a family member had Hepatitis B were nearly seven times more likely to be infected themselves, pointing to transmission within the home.

Beyond where they lived, personal habits were strongly linked to the virus. Teenagers who smoked were eight times more likely to be infected, while those who drank alcohol were seven times more likely. Sexual activity also increased the risk significantly, with sexually active teens being six times more likely to carry the virus. These findings suggest that the virus spreads through a combination of household contact and risky behaviors that are more common among those facing the stress of displacement. On the positive side, knowledge proved to be a powerful shield. Teenagers who demonstrated a good understanding of how the virus spreads and how to prevent it were far less likely to be infected. This indicates that education can change behavior and reduce risk, even in difficult circumstances.

Despite the high levels of risk, the study found that awareness was generally low. Only a small fraction of the teenagers knew that Hepatitis B is a viral infection or understood that it affects the liver. Many held misconceptions, believing the disease could be spread through shaking hands or that it was caused by bacteria rather than a virus. Stigma was also present, with many expressing discomfort at the idea of sitting next to or hugging someone with the infection. These attitudes, combined with a lack of vaccination and poor preventive practices, create an environment where the virus can continue to spread.

The researchers concluded that while the current rate of infection is moderate, the high number of susceptible teenagers is a ticking clock for future outbreaks. The combination of a large group of unvaccinated youth, the disruption caused by conflict, and the presence of risky behaviors means that the virus could spread more widely if left unchecked. The study highlights an urgent need for targeted efforts to reach these adolescents, particularly those who have been displaced. Catch-up vaccination programs, better health education, and screening services tailored to the needs of refugee communities could close the immunity gap. By protecting this generation, health officials can prevent the virus from taking hold and ensure that the next wave of infections does not follow the same path.