Homosexuality does not equal AIDS, but it is closely associated with it. AIDS was first discovered on June 5, 1981, among five gay men in Los Angeles, California, and is also far more likely to be transmitted than lesbian-gay men. The reasons for this are in two broad categories. One is biomedical causes and the other is behavioral causes. Now Davey M. Smith, associate professor of infectious diseases and director of the Viral Pathogenesis Research Unit at the University of California, San Diego Center for AIDS Research (CFAR), is a member of the U.S. Department of Health and Human Services. The latest research by Davey M. Smith and others has revealed some of these mysteries, with RNA virus particles being the culprit, and it is now known that most HIV infections worldwide are caused by exposure to HIV in semen. Semen is made up of sperm, proteins, immune cells and seminal plasma. HIV is transmitted in semen as RNA (ribonucleic acid) between men who have sex with men. Other contributing factors: Public health experts now tend to refer to this group of homosexuals, or MSM, by the term “men who have sex with men,” and other biological and physiological characteristics of the MSM population that create favorable opportunities for HIV transmission. One of the primary sexual behaviors of MSM is anal sex. Compared to heterosexual sex, the rectum is less elastic than the vagina and is more fragile, with a thinner rectal mucosa that is more prone to breakage. When the rectum is broken, the large amount of HIV contained in semen can easily enter the body and infect T cells. Now, Smith’s group has found that it is the RNA virus particles in seminal plasma that carry out the infection, so the combination of RNA virus particles and the fragile and broken rectum is one of the reasons why MSM are most likely to contract HIV. On the other hand, RNA virus particles in seminal plasma being the real culprit of infection could also explain the higher incidence of HIV infection through sexual intercourse in MSM. New statistics from the World Health Organization in 2008 show that about 70-80% of HIV infections worldwide occur through sexual intercourse. After a single episode of unprotected intercourse, the chance of HIV infection among MSM is about 0.5%-3%; however, in heterosexual sex, the chance of male to female transmission is about 0.1%-0.2%, and the chance of female to male transmission is about 0.03%-0.1%. If we translate this into a single unprotected sexual encounter, the chance of contracting HIV in MSM is 5-15 times higher than that of male-to-female transmission and 16-30 times higher than that of female-to-male transmission under the same conditions. Social and cultural causes: There is no doubt that MSM are most vulnerable to the spread of HIV for social and cultural reasons. Whether in the more open West or the more conservative East and Africa, homosexuality is not socially acceptable. This has led to an underground state of homosexuality, with several characteristics of sexual behavior. The first is multiple sexual partners; the second is a large number of casual, one-time sex in bars, parks, bathrooms, and even street corners; and the third is the non-use of condoms. These characteristics are more likely to cause the spread of HIV among the MSM population. But at the same time, society’s invisibility of homosexuality has also created another hidden evil. To conceal their homosexuality, many homosexuals are forced to marry someone of the opposite sex and cover it up by forming a family, without giving up same-sex sex. After having unsafe sex with multiple people of the same sex, they may then go home and have sex with their wives, which can spread HIV to their families and other members of the general population. This is both a greater blind spot for AIDS, as well as a blind spot for society and a greater hidden tragedy. HIV infection rates among gay men in some parts of Africa are 10 times higher than among men in other regions. Unprotected sex between men who have sex with men in the Sahara region of Africa has played a more serious role in the AIDS epidemic than might be imagined. It is also a major cause of the AIDS epidemic in Africa. Asia and China: The AIDS epidemic in Asia is “spiraling out of control” due to men having sex with men, and February 2009 statistics from the World Health Organization indicate that with an estimated 10 million MSM members in Asia, the epidemic will worsen dramatically if not prevented soon. In late 1989, the first local case of HIV infection through sexual contact was found in China in a man who had sex with multiple men. The survey found that the pattern of HIV infection in China is changing. In the past, the main forms of transmission were blood transfusions, drug use (sharing needles), heterosexual sex, homosexual sex and mother-to-child transmission. However, the rate of HIV transmission from same-sex sex is now on the rise. Sexual transmission has become the main route of HIV transmission in China, with same-sex transmission accounting for 32% of the total transmission and heterosexual transmission reaching 40%. 18 percent. This figure may be conservative as most homosexuals in China are underground. Also, with 5 million gay men in China, the odds of HIV infection among Chinese men who have sex with men are as much as 45 times higher than the general population. Of course, this is only for one city, and it is not known how other cities in China are doing. Because men who have sex with men are a not insignificant group, coupled with behavioral patterns, cultural and biological and physiological reasons, the spread of HIV among men who have sex with men has the potential to grow dramatically in China and around the world. A scientific and effective response is the responsibility of the entire community.