Hepatitis is a disease causing liver inflammation or infection. Hepatitis is caused by viruses or by unhealthy lifestyle (alcohol abuse, some medications, and trauma).
There exist hepatitis type A, B, C, D, E, non-A, and non-B, caused by A, B, C, D, E viruses.
Hepatitis A easily infects the human liver, and until the immune system defeats the virus, it will cause a lot of damage in the organ. If you want to know more about how this virus looks like you should consult Dr. Baron's Medical Microbiology textbook.
The virus is transmitted between people by fecal-oral way through infected aliments and water. Incubation period is 15 to 45 days. The infected people are contagious even two weeks before their symptoms appear.
In the developed countries, hepatitis is not so frequent because there the raw sewages are treated, and so, the water supply is not contaminated. But in the countries that are only developing, the water could be affected, and so, the most probable way to get infected is by eating fruit and vegetables from there.
Symptoms of hepatitis are: fever, headaches, fatigue, nausea, vomiting, and jaundice. Jaundice means that a person's skin becomes yellowish, and so does the white of the eyes. Also, the infected person may develop hepatomegaly (its liver swells) and pain in the right side of the body, right under the rib cage.
Symptoms disappear after three to four weeks, and most people recover well after this disease.
Generally the disease is eaten by eating fruits and vegetables that are carrying the virus, especially if they have been imported from countries that are in a process of developing.
Being a tourist is also a risk because you expose yourself to the virus when traveling in the developing countries (in Africa, Central and South America, Asia, etc).
There exists vaccine anti-hepatitis A which has been proven to be highly effective. If you do not want to take a vaccine, but also do not want to get infected, there is another solution. The doctor can help your immunization with antibodies pooled from human. If you suspect you have been infected you should go within two weeks after the infection occurred, otherwise these antibodies will not work. Also, they are active only four weeks, so if you think you are going to visit a developing country for more than a month, you should accept taking a vaccine.