A, B, C – the alphabet of hepatitis

A – like mild to severe illness of the liver. Hepatitis A is called as a “dirty hand” disease cause of consumption of contaminated food or water (fecal-oral transmission). This disorder is caused by hepatitis A virus (HAV) that replicates in the liver. There are 1.4 million of sufferers every year around the world. It is clearly connected with low sanitation. After 10 to 12 days from intake virus is replicated and released to blood stream. Then with bile is excreted with feces.

HAV remains stable in different difficult conditions and can survive outside the organism for months in relatively low pH or moderate temperature. It is sensitive to hot (85°C or higher) formalin and chlorine. The onset of acute A hepatitis is rated from 15 to 50 days from infection and it the symptoms do not differ from those occurring within other types of hepatitis. The manifestation of the disease include fever, anorexia, nausea, malaise, abdominal pain or discomfort, jaundice and dark urine. The severity seems to by clearly related to the age, because up to 70 % children go through the hepatitis without any symptom.

There are two available, effective vaccines HAVRIX (GlaxoSmithKline) and VAQTA (Merck). Both are formulated and available for adults (19+) and children (12 months to 18 years).

B stands for Hepatitis B with the etiological factor hepatitis B virus (HBV). It is also called “serum hepatitis” because t is transmitted only by blood or body fluids (semen or vagina mucus). After the infection, the virus is transmitted to liver, kidneys, pancreas and blood mononuclear cells. Despite of liver inflammation, and common symptoms it may cause also liver cancer. First symptoms appear from 2 to 6 months from the infection. Most common symptom in acute B hepatitis is jaundice.

Despite the acute form of inflammation, infected may also expand the chronic disease. It is diagnosed when the antigen HBs (HBs ag) is presented in blood during 6 months. The symptoms are nonspecific and include fatigue, somnolence or impaired concentration. After 10 to 20 years of infection in 20 %people with chronic type of disease may occur cirrhosis, in 5% may developed liver cancer.

According to WHO there are 240 mln people infected with HBV, while every year about 600 thousands of cases are fatal. To prevent the hepatitis B there is cycle of vaccination administered in 0 – 1 – 6 month of life. Uptake of those 3 injection benefits with the 95% effectiveness of the vaccination.

C means the most severe disease. Hepatitis C is caused by the hepatitis C virus (HCV). The danger lies in the fact, that the disease may pass without symptoms. During this time, person that is infected can infect many people. Moreover, the longer the disease stays hidden, the severe may be consequences – the risk of getting cirrhosis and liver cancer is raising. HCV is more virulent even than HIV and occurs in 6 types. Thus it can be transmitted relatively easily - for example, during the visit to the hairdresser or beautician.

5 to 10 mln of people in Europe may be infected, in whole world it occurs in 3% of population. As a result of the late squeal of HCV infection, about 350 thousands infected die per year. In standard treatment there is interferon with efficacy from 50 to 80 %. Still there is no effective vaccine. From 4 to 12 weeks from infection are visible first symptoms, but they are nonspecific and involve difficulty concentrating, anxiety, depression, pain in joints and muscles, itchy skin and occur only in a third of infected. During this time the acute form of disease is presented.

From 1^st of July 2013 Baltic Network (earlier Hepatitis C Network) fight against life-threatening viral infections. Main aims of the Network is to fight against viral hepatitis, HIV and influenza. The participants of the project are 12 teams form 6 European countries: Sweden, Russia, Lithuania, Estonia, Finland and Poland. Main aims of the project are: designing new vaccine candidates and develop vaccination strategies, developing new technologies that help detect the pathogens, improving the human consciousness and improve the public education.

Sources:
CDC - Pinkbook: Hepatitis A Chapter - Epidemiology of Vaccine-Preventable Diseases [Internet]. [cited 2014 Aug 4]. Available from: http://www.cdc.gov/vaccines/pubs/pinkbook/hepa.html
Vaccines: VPD-VAC/HepA/main page [Internet]. [cited 2014 Aug 4]. Available from: http://www.cdc.gov/Vaccines/vpd-vac/hepa/default.htm
Viral Hepatitis. 2012 Aug 23 [cited 2014 Aug 4]; Available from: http://emedicine.medscape.com/article/775507-overview
Hepatitis B. 2014 Jun 9 [cited 2014 Aug 4]; Available from: http://emedicine.medscape.com/article/177632-overview
WHO | Hepatitis C [Internet]. WHO. [cited 2014 Aug 4]. Available from: http://www.who.int/csr/disease/hepatitis/whocdscsrlyo2003/en/index4.html
http://www.cdc.gov/hepatitis/c/cfaq.htm

Hanna Banasiak