April 9, Vitebsk /Olga Bogacheva - BELTA/. Approximately 30 new cases of HIV infection have been detected in the Vitebsk region during the first quarter, which is a 52.6% increase compared to the same period last year, Valentina Ananyeva, Head of the AIDS Prevention Department of the Vitebsk Regional Center for Hygiene, Epidemiology and Public Health, informed a BELTA correspondent. As of April 1, a total of 701 cases of HIV infection have been registered in the region. The incidence rate was 2.4 per 100,000 population, compared to the national rate of 3.4. The most affected districts in the region are Liozno, Tolochin, Gorodok, Dubrovno, Polotsk, and Vitebsk districts, as well as the cities of Polotsk and Vitebsk. The age structure of those infected is gradually changing. The epidemic process primarily involves the working-age, fertile population aged 25-39 (55.5% of cases, 389 people). The proportion of infections in the age group over 30 has significantly increased: from 36% in 2006 to 67.1% in 2011, and 69% in the first quarter of 2012. A significant increase is also observed in the 35-39 age group: from 14.3% in 2008 to 31% in 2012. Furthermore, there is a trend towards an increase in the proportion of sexual transmission of HIV (from 76% in 2006 to 78.1% in 2011). In the first quarter of 2012, sexual transmission accounted for 86.2%. The proportion of sexual transmission of HIV infection is growing among both women and men. Last year, 90.9% of women and 67.5% of men were infected this way. In the first quarter of 2012, this figure was 78.6% for women and 93.3% for men. Between 2006 and 2010, a decrease in the proportion of parenteral infection was achieved, from 20% to 11.5%. In 2011, parenteral transmission accounted for 20.5%, and in the first quarter of the current year, it was 13.8%. However, there is a trend towards an increase in HIV transmission through injecting drug use. The proportion of workers and employees involved in the epidemic process is increasing. Over the past few years, the proportion of workers among HIV-infected individuals has gradually increased: in 2009, it was 23.9%, in 2010 - 37.2%, and in 2011 - 54.8% (40 out of 73 people). Among those HIV-infected in the first quarter of 2012, workers and employees constitute 21%.