MONTEVIDEO, Dec. 1 (Xinhua) -- Uruguay has effectively controlled the spread of the Human Immunodeficiency Virus (HIV), showed a research released by the country's health authorities said Monday, the World AIDS Day.

    The research said the HIV prevalence has fell to 0.43 percent of the national population, with less than one person being diagnosed with HIV infection daily.

    The reduction is a result of the country's sexual transmission diseases prevention campaign, director of the national STD program Maria Luz Osimani told the press.

    Currently 10,996 people, mostly aged between 15 and 44, in Uruguay know they have HIV. The country has a population of 3.4 million.

    HIV infection is concentrated in the most vulnerable groups, like sexual workers, homosexuals and people prevented from their freedom, the research said.

    Osimani said that the implementation of a single register of HIV carriers, a sustained campaign by the mass media and intervention in the most vulnerable populations are "future challenges."