In 2015 alone, over 1 million migrants entered Germany, the vast majority fleeing from war-torn countries like Syria, Afghanistan, and Iraq. Most were refugees hoping to gain asylum in a European country — places where they may find more job opportunities, and be safe from the conflict back home.

To put the numbers into context, there are some 80 million people living in Germany. As more refugees enter the country, the healthcare system will need to prepare in order to sustain all of them. Refugees will likely have to be treated for a wide range of health issues — including mental health problems like post-traumatic stress disorder (PTSD). But a new study suggests that one of the bigger concerns is treating the diseases that have long since been nearly eliminated from Europe due to immunization — like tuberculosis, measles, mumps, or Hepatitis B.

In a new study, researchers in Hanover, Germany, analyzed data showing that the prevalence of Hepatitis B is higher among refugees than the general German population. The study was presented at the International Liver Congress in Barcelona, and led by Dr. Philipp Solbach of the department of gastroenterology, hepatology and endocrinology of the Medizinische Hochschule Hannover. The study is one of the first to document the prevalence of disease among refugees, and offers clues into how doctors and healthcare workers may begin to tackle the problem.

Hepatitis B is an infectious viral disease that attacks the liver. Initially, it may be difficult to detect, as symptoms are sometimes invisible. There are two types of the infection: acute or chronic. Patients with acute infection typically overcome it in a matter of weeks or months, while those with chronic Hepatitis B may have a higher risk of developing liver disease later on, though treatment can usually prevent that. According to the World Health Organization, some 240 million people are chronically infected with Hepatitis B.

In the study, the researchers examined 793 refugees of all ages who were living in refugee reception centers in northern Germany in August 2015. They tested for serological markers (in a component of blood called serum), as well as liver enzymes, that would show Hepatitis B virus infection. They found that the rates of Hepatitis B infection among the refugees (2.3 percent) was significantly higher than that of the German population (0.7 percent), or Europe in general (2 percent).

What’s interesting, however, is that the researchers decided to compare the results to the prevalence of the virus in immigrant populations already living in Germany. What they found was rather surprising: Up to 5 percent of immigrants in Germany have Hepatitis B, and a large chunk are unvaccinated. “The prevalence among refugees is higher than the German population, but it’s not higher than the immigrants who already live here in Germany,” Solbach told Medical Daily. “They are not more infectious than some people who are already living here.”

Solbach pointed out that when you look at the prevalence in the countries of origin, the high rates begin to make more sense: Refugees are coming from places that don’t have rigorous immunization systems, or easy access to diagnoses. “Syria has a Hepatitis B prevalence of around 2.6 percent, Iraq and Afghanistan a little bit lower, and Albania is quite high, at about 7.7 percent,” Solbach said. “In the European region it’s 2 percent, so there’s a pretty huge difference.” Worldwide, prevalence of Hepatitis B is 3.6 percent.

How high is the risk of infection?

In their study, the researchers note that the results cause concern about public health, but to what extent is the risk of refugees infecting other unvaccinated people living in Germany? That’s something that the current study didn’t answer, Solbach notes, as they don’t have information about the level of infection.

However, if we look at the low vaccination rates among refugees, the primary concern seems to be spreading the virus among other refugees, especially in the close living quarters within shelters. It’s especially concerning since Hepatitis B was found to be highest in young males (2.5 percent), who may have a higher likelihood of being sexually active. Hepatitis B is transmitted through blood, semen, or bodily fluid contact — or via mother-to-infant transmission.

Upon examining the vaccination rates among different age groups, the researchers found that the youngest age group, between zero and 17 years old, had only a 33-40 percent vaccination rate. The majority — 60-70 percent — aren’t vaccinated at all.

“You can see the vaccination rate is poor,” Solbach said, especially compared to the 90-100 percent vaccination rate in Germany. “The coverage rate in Syria before 2010 was high, but in 2010 the civil war started and it decreased. So here we have to look, especially for the youngest, to help vaccinate them.”

The good news, Solbach points out, is that the system for vaccination is pretty strong in Germany — and he believes the health care system will be able to manage the several thousand new patients who need Hepatitis B treatment. “I think the German system will handle it,” he said. “They can do it because the ability to be vaccinated for [hepatitis B], or other diseases like tuberculosis, mumps, and rubella virus, is high.”

Source: Solbach P, et al. PS137, Hepatitis B seroprevalence and immunization status of refugees seeking asylum in Germany in the current Middle-East crisis. European Association for the Study of the Liver, 2016.