1.1 Introduction

Drinking out of someone's glass who has AIDS is like playing Russian roulette. Playing sports together is asking for trouble, and kissing is suicide. AIDS is surrounded by quite a few myths. But also with other infectious diseases, people are quick to jump to conclusions conclusions which often are based on little more than fear. For example, at the end of the Olympic Games of 1988, downright panic broke out when it became known that diver Greg Louganis apparently was infected with HIV. The 'Golden Boy' of Seoul hit the diving board with the back of his head and fell into the water with a bleeding head wound. Only afterwards did the Gold Medal winner announce that he was HIV positive. The world was furious: By spreading the AIDS virus throughout the pool, God only knows how much danger he had exposed his fellow divers to. One probably forgot that all the chlorine in the swimming pool had disinfected the water. And what is more, HIV cannot survive outside of the body. Therefore, there was no danger of an infection whatsoever. The only person exposed to any danger was the physician who had sutured the head wound. Louganis had not told him either that he was HIV positive, so the physician could not take any measures to protect himself.

A second example, also from the world of sports: On November 7, 199 1, Earvin 'Magic' Johnson gave up his brilliant basketball career. The reason: the Laker star was infected with HIV and did not want to knowingly infect his fellow players. The question is, how big was the danger of infection really? HIV can only be transmitted through unsafe sex (without the use of condoms) and direct blood contact. Since this incredibly tall basketball player only shared the field (but not his bed) with his fellow basketball players, the virus could only be transmitted through direct blood contact. Through small wounds, or mouth, nose and eyes, blood particles of one person might get into the bloodstream of another person. However, this possibility is very small. However, Johnson did not want to take any risks and left the game. The third and last example: In 1997, a judge in the Netherlands sentenced an HIV positive woman to 24 months in jail, 8 of which were probation. When caught shoplifting, she had bitten a security guard. Attempted manslaughter was considered not proven, since experts put forward that the chance of transmitting HIV through a bite was approximately one in a billion. Just as with Johnson's fellow basketball players, the physician who treated Louganis, and the Dutch security man, there is a certain chance that you, as prison guard, might catch an infectious disease while at work. But here too, the question is: How big is this risk really?

A risk analysis

In general one could say: The more serious the illness, the less the risk of infection. The same applies vice versa: The greater the risk of infection, the less serious the illness. Hepatitis A is relatively harmless but very contagious. Each year, over 10 billion people world-wide are infected with hepatitis A. The flu even has an infection risk of 100%, but for most people, the flu is harmless. So far, the initially expected AIDS epidemic has not occurred, simply because the risks of infection are limited. People do not get AIDS from talking to someone, as can happen with the flu. You cannot get AIDS from someone coughing in your face, as happens with active tuberculosis. You d not catch AIDS from infected water as you do with hepatitis A. Sharing the same bed with someone can result in getting scabies but not AIDS. A mother who chews the food for her baby can infect the baby with hepatitis B but not with AIDS. A dirty toilet seat can give yo a painful boil but cannot give you AIDS. Okay, purely hypothetically, one could catch AIDS in the street if a gust of wind blows infected blood in one's eye but that possibility is just as remote as the impact of a large meteorite: Meteorites the size of a large passenger ship hit earth on average once every hundred thousand years.

This chapter deals with infectious diseases. How do you get infected? How can infections be prevented? And what are the symptoms if someone is infected? The facts about infections.