Expert: Kristen Brannock, MPH - 3/18/2005

Question
In my consolation and test work, I encounter a few policemen who were hurt by HIV-infected person. Also, in the world-famous Wenlou "AIDS" village in Henan province in China, more than one half villagers catched HIV through selling blood. Because of poverty, many HIV-infected villagers commit robbing and racketeering, making use of the people's fear of HIV. Some villagers even assault policemen when confronting them. So far more than one hundred policemen in Wenlou village have been hurt by assaultive HIV-infected villagers by nail scratch and biting. Almost all policemen hurt by HIV-infected person resorted to medical evaluation and asked for postexposure Chemoprophylaxis.


Here I want to ask what level of the risk is, and whether it is warranted when the policemen are only hurt by nail scratching by HIV-infected person.

Your response based on scientific argument is much appreciated.

Thank you and best regards.


Answer
HIV transmission happens when infected blood, semen, vaginal fluid or breast milk enters another's body. In the case of scratching or nail biting, those are not very risky situations. It would be very hard for HIV to be transmitted in such a case unless there was a lot of blood present and an easy way for exchange to happen. My guess is that by giving the police officers chemoprophylaxis they are operating under the "better safe than sorry" principle and not because it is a high risk situation.