Hepatitis B is a notifiable disease in all the countries in the region. However, not all of the countries have systems to separate acute infections from a chronic carrier state. This is the case for Iceland and to some extent Estonia. The other countries in the region are able to distinguish and report separately the two forms of the disease. In Northwest Russia, chronic hepatitis B and hepatitis B carriers are reported separately. All the countries report only laboratory confirmed cases.
Figure 6. Number of cases of acute hepatitis B notified in 2003 per 100 000 population (1)
The overwhelming majority of notified acute cases of hepatitis B in the region occur among intravenous drug users. In the Nordic and the Baltic countries, the incidence rates of hepatitis B fell dramatically in the early 1980s. This followed the introduction of targeted vaccination programmes among high-risk groups such as drug users and homosexual males. The introduction of HIV preventive measures such as disposable syringes in the medical services contributed to the fall in incidence rates in the eastern part of the region. However, in the 1990s, many of these countries re-experienced a surge in incidence rates caused mainly by outbreaks among groups of non-immune drug users. This coincided with an increase in the number of young people injecting drugs. In the early and mid-1990s, a growing number of intravenous drug users resulted in very high incidence rates of hepatitis B in both Northwest Russia and the Baltic countries.
Finland, Norway and Sweden have since the late 1990s experienced large nationwide outbreaks in drug users and the disease seems again to be endemic in this high-risk group. The number of newly diagnosed cases has dropped considerably in the eastern part of the region (figure 7). A combination of effective preventive measures and decrease in numbers of susceptible drug users may have contributed to this improvement. The spread of hepatitis B among drug users has resulted in a growing number of sexually transmitted cases among drug users sex partners, usually female partners. As a consequence, mother-to-child-transmission of hepatitis B has become a concern in most of the countries in the region.
Figure 7. Number of cases of acute hepatitis B notified per 100 000 population 1999-2003 by groups of countries or regions (1). Iceland, Komi, Pskov, Novgorod and Vologda regions not included.
Transmission of hepatitis B by other routes than needle sharing and sex is rare in the Nordic countries, while nosocomial infections mostly occur in the eastern part of the region. Likewise, health care workers in the eastern part of the region are at greater risk to contract hepatitis B than in the Nordic countries.
In the Nordic countries, immigrants from highly endemic countries constitute the overwhelming majority of notified cases of hepatitis B carriers. Most of these patients have acquired their infection at birth or in early childhood in their former country of residence. The number of notified chronic hepatitis B carriers therefore usually reflects the number of immigrants entering the countries each year. Due to the increasing number of acute cases in drug users and their sex partners, more and more cases of the chronic, carrier state are being diagnosed in this group all over the region.
Seroprevalence studies among injecting drug users performed 2000-2002 in the region have shown the following prevalence of any hepatitis B markers of previous or current infection: Estonia 65%, Latvia 38%, Lithuania 7%, Norway 53% and St. Petersburg 16% (8,9).
The most important prevention measure in the entire region is to reduce transmission of the hepatitis B virus among drug users. This will again lead to a reduction of sexual and mother-to-child transmission. For prevention measures among injecting drug users, see HIV-infection.
Hepatitis B vaccine is a part of the national immunisation programmes in Russia and in the Baltic countries. In these countries, vaccination is carried out in the newborns. In addition, special programmes are aimed at vaccinating large groups of teenagers. This is seen as an important measure to quickly reduce the incidence rates in drug users. In the eastern part of the region, implementation of hepatitis B vaccination of newborns and teenagers has been slow due to lack of funding. Improved funding and bilateral projects between the Nordic countries and regions in Northwest Russia as well as funding from the Vishnevskaya-Rostropovich Foundation has now resulted in high vaccination coverage in newborns and some teenage cohorts. Close contacts to persons with acute disease or carrier state is also offered hepatitis B vaccination in Russia.
None of the Nordic countries have so far included the vaccine in their national vaccination programmes. Instead, they have adopted a strategy of selective vaccination of high-risk groups such as drug users, men who have sex with men, close contacts to known carriers, haemophiliacs and people with underlying liver disease. The costs of the selective programmes are covered differently in the various Nordic countries, but in all countries vaccine is given free of charge to most targeted groups.
In contrast to the rest of the region, few vaccination campaigns have so far been directed towards the drug communities in Northwest Russia. One exception is the region of Kaliningrad where a special vaccination project aimed at youth at risk for drug use has been started. Health care workers are extensively vaccinated against hepatitis B in most parts of the region.
Estonia, Iceland, Latvia and Northwest Russia have introduced a universal screening policy for pregnant women. Due to lack of funds, however, not all pregnant women are screened for hepatitis B in Northwest Russia. In the other Nordic countries, screening of pregnant women is selective.