It is caused by human immunodeficiency virus that causes AIDS, the prevalence varies from country to country. We prevalence rate among adults in the various countries are, according to various sources Since 2009, an estimated 33.3 million people worldwide infected with HIV live for. AIDS epidemic in sub-Saharan Africa are the countries that much. More than 60 percent of people with HIV to spend your life in those areas. HIV prevalence among adults in Botswana and Lesotho Svyzylnd and is more than 20%, while in six other countries the prevalence in adults less than 10% have been reported. In terms of numbers, South Africa has the largest HIV-infected population of 6.3 million, followed by Nigeria with 3.2 million and India with 2.1 million and this is the end of 2013. This means that a large percentage of the population is HIV-positive people in South Africa, which is 17.3 percent that neither Nigeria nor India with 3.7% and 0.3% in terms of percentage of the population infected with HIV in Nyst.v this large population Nigeria and India are positive for high levels of population of the two countries is 174 million and 1.25 billion, otherwise in percentage terms with a more Payyt level. On the other side of this review, Svalbard is that no cases of AIDS or HIV have been reported, while Bhutan has a population of only about 246 more cases were reported in 2011. Countries like Afghanistan has the lowest incidence of disease, less than 0.1% of the population. As the majority of people infected with HIV are unaware of their status, it is reasonable to expect that a significant cases may not be reported and there may be mentioned that the accuracy of the statistics.