Iran said Monday that the country has registered more than 18,000 HIV-positive citizens and is worried that number could rise in a rare government disclosure about the AIDS causing virus. Health Minister Kamran Bagheri Lankarani said increasingly Iranians were transmitting HIV through "illegal sexual relations," meaning adultery, prostitution and homosexuality, which are all illegal in Iran. Talk of HIV, AIDS and sex outside of marriage is taboo in Iran, especially by government officials. Though Iranian officials have acknowledged HIV exists, it is also rare for the government to announce any figures or admit the virus was spreading through sexual contact. "What we are worried about is a third wave of the AIDS epidemic through sexual contact given that a majority of our population are young people," Lankarani said on state television Monday to mark World AIDS Day. Abbas Sedaqat, head of the ministry's AIDS Department, said the number of HIV infections was steadily increasing.