Charlie Sheen has HIV. Here are 5 things you may not know about the virus.

When Charlie sheen announced this morning that he was HIV positive, the news probably surprised some and not others, the latter perhaps because his lifestyle included several risk factors for transmission. But others may have been surprised just because, well, a lot of people have forgotten that HIV is still present in the United States now that it isn’t making the headlines like it used to be.

“People have become very happy with HIV because we don’t see it like in the 80s and early 90s,” said Dr. Louis Picker, professor of pathology and associate director of the Vaccine and Gene Therapy Institute at the ‘Oregon Health & University of Sciences. “Because of the antiretroviral drugs, it kind of went underground in the United States,” said Picker, who graduate medical school at the University of California, San Francisco in 1982 – at the heart of the epidemic when it started. He has made the development of an HIV vaccine his life’s mission.

Just one more half a million Americans have died of AIDS since the start of the epidemic, and over 14,000 people still die of AIDS each year in the United States Picker told me. “And we don’t see sub-Saharan Africa where 50% of women presenting for antenatal care are HIV positive and don’t know it.”

Gone are the years when all the Hollywood stars wore red ribbons on stage, but HIV and AIDS are very prevalent. Here are some things you may not know about the virus.

1. Couples can now have biological children when a parent is HIV positive.

Among the millions of people who live long and actively with HIV, some may wish to start a family. Some might adopt – if approved – but pre-exposure prophylaxis, or PrEP, and “treatment as prevention” are two methods that allow “mixed HIV status couples” to have their own children. Treatment for prevention means treating someone who is HIV positive to such an extent that their viral load is so low that there is not enough virus in their body fluids to pass it on to their partner (or future child). Research has shown that it can reduce transmission by up to 96%. During this time, PrEP is a prevention method in which partners who are not infected with HIV take a medicine called Truvada (see more in # 2). In his moving book Positively negative: love, pregnancy, and science’s surprising victory over HIV, extract here, journalist Heather Boerner describes how little Pom-Pom Morgan came into the world HIV-free even though her father has it and she was conceived in an intimate, secular way. *

2. Treatment with PrEP can help prevent the transmission of HIV – if people can get it and take it regularly.

As noted above, PrEP can prevent an HIV-positive person from getting the virus even if they are exposed to it, reducing the risk by up to 90%. So, for those who are not interested in parenting, PrEP has made fearless intimacy possible for mixed couples, with studies showing that PrEP is “very effective” in preventing transmission between sexual partners. Corn obstacles to widespread use to stay. The drug has to be taken every day to be 90% effective, and it is not cheap, costing up to $ 13,000 per year, although Gilead, the maker of Truvada, will provide it to some for free, and Medicaid covers it for some. It is an ideal option for populations at risk, such as gay men, but not so insurance does not pay, and even heterosexual women seeking to use it have met with resistance from their doctors. It is an expensive and maintenance-intensive palliative until the real holy grail, a vaccine.

3. A vaccine to prevent HIV is really on the horizon, maybe in a little over a decade.

The best prevention would obviously be a vaccine, something Picker has made his life’s mission. Having graduate medical school at the University of California, San Francisco in 1982 – at the heart of the epidemic just at the start – Picker lost friends and family to AIDS. He described two types of vaccines the researchers worked on, one that “might work at the infection prevention level or might work at the infection control level before you know you are. infected”. The first, which induces antibodies to prevent infection – the familiar mechanism used by most childhood vaccines – didn’t work much. “So far, all but one human trials have failed, and this one has not been effective enough for licensure,” Picker said. “It’s really hard to make an antibody vaccine to prevent this infection. “

Its own vaccine works differently: It works by preventing the spread of an infection by causing the killer T cells to recognize and kill cells infected with the virus before they get very far. He does it by using cytomegalovirus (CMV) as a dual agent. Over 80% of Americans have had a CMV infection, but it is usually mild except in young babies. The virus does not go away, however, the immune system is always on guard to fight it. By injecting HIV DNA into CMV cells, Picker’s vaccine triggers the immune system to attack any cell that contains HIV. “The infection is controlled very early on, and over time all cases of the virus are cleared,” he said. It has been 50% effective in monkeys and has the potential to be used therapeutically, also for those already infected. He estimates we’ll have it in 10 to 12 years, and the closest thing possible to a cure – no detectable level of virus in the body – might follow soon after. “With HIV, the field is looking for a working cure,” he said. “It will probably be 10-15 years from now, but if we keep an eye on the ball I think we can do it.

4. Until then, the epidemic continues to grow, abroad and in the United States.

Almost as many people have HIV today as people who have died from it since we learned about it. About 37 million people around the world, including over 3.2 million children, were living with HIV at the end of 2014, equivalent to just over the total population of Canada. With over 2 million new infections a year, we’re on the verge of passing 39 million, the total number of people who have died, or roughly the population of California today.

About 1.2 million people living with HIV are in the United States, and the numbers are increasing: the United States has 50,000 new HIV infections and 14,000 AIDS deaths each year, and one in eight people infected with it does not even know she is HIV positive.

5. Charlie Sheen? Like Magic Johnson, he’ll probably be fine. Millions more will not.

Sheen isn’t guaranteed to live a long, normal life, but it’s highly likely given that he has the resources to do as well as Johnson has all these years. “Statistically, people who have treated infections are going to vary quite a bit,” Picker said. “The drugs will work very well on some people and in others they will smolder below,” putting them at a higher risk of immune problems, certain cancers and other diseases.

But that’s with access to treatment. Three in five people worldwide do not have access to antiretroviral drugs that keep viral loads low enough for people to lead normal lives, and less than a third of people living with HIV in the United States have their infection under control.

“It’s a problem and will continue to be a problem until, like smallpox and almost polio, we get rid of it,” Picker said. “We don’t see it on the streets anymore, so there isn’t as much support to finish it off, including within government, but it’s not over until it’s over.”

* This paragraph has been amended to correct a previously inaccurate description of how a child of mixed couples might be conceived. The medicine Truvada, a form of PrEP, is taken by HIV negative people or is taken in combination with other medicines by HIV positive people, but not alone by HIV negative people.

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Sara R. Cicero