Well,
i'll tackle the first one and then move on, the transmission of hiv is quite ineffective through sexual means, it is however very easy to transmit via exchange of bodily fluids i.E. Blood. "based on studies measuring heterosexual and homosexual transmission, transmission depends on an average of 1000 heterosexual contacts, and 100 to 500 homosexual contacts with antibody-positive people." these numbers would serve as proof that sexual transmission is very unlikely without the exchange of blood. Now with all that said, the original question was: is aids contagious, and well the answer is simply no. Aids is a condition, and by definition it is a syndrome that needs only the presence of the hiv virus to somehow warp many existing diseases into "aids" so no this condition in itself is not contagious.
As for the second poll question, no one seems to have a firm hold on the true age of hiv, all that is known is that advancements in technology have made it easier to find, such as the procedure that was discovered by kary b. Mullis know as polymerase chain reaction, which identified an even larger section of the population living with hiv, but in such small amounts that antibodies were not detected. So, one must ask the question.......If so many people are found to have hiv through new methods such as the polymerase chain reaction, why then havent new aids cases grown along with those numbers?