When a person is doing intercourse he is transfrring the specific virus from his semen to that person. More than half a million of are people are dying every year because of these killer viruses. More than three million people were died worldwide because of hiv/aids. This data has been collected from UNAIDS(United Nations Programme on HIV/AIDS). This is mainly transferred through semen. During pregnency mother can transfer this disease to their infants. Hiv can transfer to blood by many factors such as anal or veginal sex which is unprotected, through the tranfusion of blood whose blood can have hiv virus, and through the injections while taking drug and blood.
The treatment to combat this virus so far has not been implemented and the only way to prevent this condition is the use of condom. Some of the countries which are worsely affected from this disease are west african countries and India. This is mainly because of the lack of education in these countries. One more method from which we can control this is the screening of blood when the tranfusion of blood is done. After the implementation of these methods the rate of this disease (hiv aids) has came down fastly.