Question

cause ,epidemiology, incubation period, diagnosis, sign, prophylaxis, treatment and prevents of AIDs

Answer 1

The Facts

AIDS (acquired immune deficiency syndrome) was first recognized in North America in the early 1980s. It is caused by a virus known as HIV (human immunodeficiency virus). HIV infection has become a worldwide epidemic. The World Health Organization estimates that since its discovery, it has caused 36 million deaths worldwide. In 2013, approximately 35.3 million people were living with AIDS. In Canada, over 23,000 AIDS cases were recorded by The Public Health Agency of Canada between 1979 and 2014.

HIV is more common among certain populations at risk, such as bisexual and gay men and people who inject illicit drugs. The infection is also more common among socially disadvantaged communities.

Causes

The virus can be found in the blood, semen, vaginal fluid, and breast milk of infected people. HIV is also found in saliva, sweat, and tears, though not in high enough amounts to transmit the virus to another person. There are no known cases of anyone catching HIV through sneezing, shaking hands, or from toilet seats or mosquito bites.

The two most common ways to be infected with HIV in North America are through unprotected sex and sharing needles. HIV may be transmitted through unprotected heterosexual or homosexual, vaginal, anal, or oral sex. Although the risk of infection is lower with oral sex, it is still important to use protection during oral sex, such as a dental dam (a piece of latex to cover the vagina during oral sex) or a condom. HIV can also be passed on through perinatal infection, where mothers who have HIV are at risk of giving the disease to the baby during birth. The risk of perinatal infection is declining with new treatments. Breast-feeding by an infected mother can also transmit HIV.

Once HIV enters the bloodstream, it takes over cells vital to the immune response, known as CD4+ lymphocytes. The virus then inserts its own genes into the cell, turning it into a miniature factory that produces more copies of the virus. Slowly, the amount of virus in the blood goes up and the number of healthy CD4+ cells goes down. The destruction of CD4+ cells interferes with the body's ability to fight off infections, cancers, and other diseases.