AIDS virus leapt the species barrier early last century: study

The AIDS virus, previously thought to have been transmitted from chimps to humans in the 1930s, may have leapt the species barrier more than a century ago in west-central Africa, scientists said on Wednesday. Analysis of tissues preserved by doctors in the colonial-era Belgian Congo shows that the most pervasive strain of the human immunodeficiency virus (HIV) began spreading among humans at some point between 1884 and 1924.

“The diversification of HIV-1 in west-central Africa occurred long before the recognised AIDS pandemic,” they announced in the British-based science journal Nature.

AIDS first came to public notice in 1981, when alert US doctors noted an unusual cluster of deaths among young homosexuals in California and New York.

It has since killed at least 25 million people, and 33 million others are living with the disease or HIV, the virus that causes AIDS by destroying immune cells.

Epidemiologists trying to date the history of HIV have until now been limited to only one laboratory source that long precedes the detected start of the outbreak.

This is a now-legendary blood sample called ZR59, which was taken in 1959 from a patient in Leopoldville, now Kinshasa, then capital of the Belgian Congo, now the Democratic Republic of Congo (DRC).

HIV is highly mutating virus, with as much as one percent of its genome diverging per year.

This rate of mutation gives rise to a measurement called a “molecular clock,” a timescale at which the HIV deviates from previous strains and from its animal ancestor, the simian immunodeficiency virus (SIV).

By this calculation, HIV began to spread among humans before 1940, according to ZR59’s genes.

Now, though, another precious piece of the jigsaw has emerged.

It is a piece of lymph node tissue that was taken for a biopsy from a woman in Kinshasa in 1960 and preserved in a bed of paraffin wax. It was found in the archives of the Anatomy Department at the University of Kinshasa.

An international team of sleuths pieced together the genetic sequence of the virus — the sub-group M of HIV-1 — and then compared telltale regions between ZR59 and the second sample, DRC60.

They found a significant divergence between the two genetic regions, and calculate that this gap must have taken around 40 years to evolve from a common viral ancestor.

In other words, the ancestral virus began to be transmitted among humans at the start of the century — the estimated range is between 1884 and 1924.

The virus spread only very slowly at first but got a vital foothold thanks to urbanisation during the colonial era, the authors speculate. It was transmitted through sex and then was taken further afield through commerce.

“The founding of and growth of colonial administrative and trading centres such as Kinshasa may have enabled the region to become the epicentre of the HIV/AIDS pandemic,” they suggest.

Kinshasa was founded in 1881, Brazzaville (capital of today’s Republic of Congo) in 1883 and Yaounde (Cameroun) in 1890, while Bangui (Central African Republic) was established in 1899.

All of these towns were founded before or at around the time that HIV-1 is believed to have entered the human population, the investigators note.

The growth of these towns was at first slow. Until 1910, not one of them had a population of more than 10,000 people.

There are several theories that seek to explain how SIV entered humans, the animal primates’ closest relative.

An infected chimpanzee bit a human, or a SIV-infected ape was butchered and sold for bushmeat, and the virus entered the bloodstream through tiny cuts in the hand, according to these hypotheses.

The new research was led by Michael Worobey of the Department of Ecology and Evolutionary Biology at the University of Arizona in Tucson.

Global AIDS prevention gives short shrift to gays

MEXICO CITY, Mexico (AP) -Jorge Saavedra’s moment of truth came in the middle of an impassioned speech to 5,000 people about the paltry amount of money being spent to stop the spread of AIDS among gay men.

The Mexican federal official paused, then said publicly for the first time that he was gay.

As he held up a photo of himself with his partner, the crowd applauded wildly. Afterward, men from Africa and India congratulated him with tears in their eyes.

“They told me that I was a hero, and that they wished they could do the same in their countries,” said Saavedra, who is infected with HIV and also heads the AIDS prevention program in a country where many gay men live in denial.

Saavedra’s coming out on Tuesday at the International AIDS Conference sent a powerful message to the world: Homophobia must be stamped out if AIDS is to be controlled.

Fewer people are dying from AIDS, but new HIV infections among gay and bisexual men in many countries are rising at alarming rates.

Yet less than 1 percent of the $669 million reported in global prevention spending targets men who have sex with men, according to UNAIDS figures from 2006, the latest available data.

UNAIDS says these men receive the lowest coverage of HIV prevention services of any at-risk population. And experts say discrimination has driven gay and bisexual men in developing nations underground — turning them into one of the epidemic’s hardest groups to reach. From Mexico to India, a surprising number of men who have sex with men insist they are not gay, and in many countries, governments still refuse to admit homosexuality exists.

“It’s very difficult to provide services to men who have sex with men in countries that don’t acknowledge they exist or criminalize them if they do exist,” said Craig McClure, executive director of International AIDS Society, which organized the conference.

In 86 nations, homosexual sex is considered a crime, and in seven countries it is punishable by death, according to the Foundation for AIDS Research, known as Amfar.

During the conference’s inauguration, U.N. Secretary General Ban Ki-moon urged nations “to follow Mexico’s bold example and pass laws against homophobia.”

In 2003, Mexico banned discrimination based on sexual orientation, and it has opened what it calls homophobic-free health clinics. The government has a national campaign that includes radio spots with mothers accepting their gay sons. Saavedra’s program has earmarked 10 percent of its $12 million budget toward prevention among gay and bisexual men.

Worldwide, few developing nations check the rates of HIV infection among men who have sex with men, but researchers who have surveyed some of these countries say they are finding the rates are nearly twice that of the general adult population.

“This fight needs to be driven by epidemiologists” who urge making this high-risk group a priority, not only for the human rights argument, but for the public health argument, said Chris Beyrer, director of the Center for Public Health and Human Rights at Johns Hopkins University. “It’s a virus so you need to put the money where the virus is.”

Gay and bisexual men are 19 times more likely to become infected with HIV than the general adult population, according to Amfar, which collected data on these men in 128 countries. In Mexico, this group is 109 times more likely to acquire HIV. To date, 57 percent of the HIV diagnoses in Mexico are from unprotected sex between men.

Thailand is seeing “an emerging epidemic of really unbelievable proportions” among its gay and bisexual men after being held up as an example for its success with a massive condom campaign that curbed HIV’s spread among sex workers, drug users and migrants, said Kevin Frost, Amfar’s chief executive officer.

Prevalence of HIV among gay and bisexual Thai men was more than 15 percent this year compared to 1.4 percent for the general adult population, according to Amfar. Frost said the country’s prevention programs ignored one of its most vulnerable groups.

“These men believed they were not at risk because they were not having sex with sex workers or women, which is what the campaign focused on,” Frost said. “That scenario is being played out across the developing world.”

Complicating matters is that in countries from Latin America to Southeast Asia, many men who have sex with men, insist they are not gay. More than 30 percent of Latin American men who reported having sex with men said they also had unprotected sex with women, according to UNAIDS. Many are married.

“Everybody knows somebody like that,” Saavedra, 48, said. “Instead of saying they are gay, it’s easier for them to justify their behavior. They say they were drunk and they were really sexually excited and willing to have sex with whomever.”

Some have beaten up transvestites after having sex with them because they are ashamed of themselves, experts say.

Even governments deny these men exist. Last year, Iranian President Mahmoud Ahmadinejad said at Columbia University in New York, “In Iran we don’t have homosexuals like in your country.”

In Malawi, that country’s first organization working on behalf of gay men was created in 2006 with the backing of World Bank officials and other international agencies.

Called the Centre for the Development of People, the group surveyed 100 gay men about discrimination to prove to the government that such men existed in Malawi. Homosexual sex is punishable up to 14 years in prison in the African country.

The organization also found through testing 200 gay men that about 21 percent carried HIV compared with 12 percent for the general adult population.

“This means that we are not moving ahead with the fight against AIDS,” said Gift Trapence, the organization’s director who has received e-mails threatening hanging.

AIDS activists say they avoid using words like “homosexual” or “gay” and instead use the label “men who have sex with men,” or MSM, so their work is not impeded by the stigma.

Ashok Row Kavi said he has learned the importance of carefully choosing his words in India, where he started one of the country’s first organizations to work with gay and bisexual men.

The Humsafar Trust found nearly 14 percent of the gay and bisexual men it surveyed in 1999 were infected with HIV. Kavi said when he told India’s AIDS officials they “totally panicked because until now they believed these men did not exist.”

But last year they added a definition of men who have sex with men to their health planning program to start prevention campaigns. The definition includes married men.

Kavi has been training health workers how to ask men if they have had gay sex and not scare them away.

“I tell them to say things like, ‘There are many cultures where men are very close to men. Are you one of these men?'” he said. “These questions have to be sensitive,” especially in India, where sodomy is illegal.

“That’s why the word homosexual is not used,” he said. “If anyone asks a man that, he will slap you.”

Deadly skin cancer may be caused by virus

A previously unknown virus may be to blame for a rare but deadly form of skin cancer, opening the prospect of new ways to treat and prevent the condition, scientists said on Thursday.

Merkel cell carcinoma (MCC) mainly affects older people and those whose immune system has been compromised by AIDS or organ transplant drugs, raising suspicions it could have an infectious cause.

Now researchers at the University of Pittsburgh Cancer Institute believe they have found the culprit, after identifying viral DNA sequences present in 80 percent of Merkel cell tumors.

The foreign DNA belongs to a virus, dubbed Merkel cell polyomavirus (MCV), which integrates into the tumor’s own genome in a way suggesting it is a trigger for cancerous growth.

If the new virus is proved to be the cause it should give new leads for treating a particularly aggressive cancer. Experts suspect the virus is deadly because it produces a cancer-causing protein or knocks out a gene that suppresses tumor growth.

“Information that we gain could possibly lead to a blood test or vaccine that improves disease management and aids in prevention,” said Dr Patrick Moore, who with colleagues published the findings in the journal Science.

Merkel cell carcinoma develops from specialized nerve cells that respond to touch or pressure. Its incidence has tripled over the past 20 years and there are now about 1,500 cases a year in the United States.

About 50 percent of patients with advanced disease live nine months or less.(My italics).

Merkel cell carcinoma is not the first cancer linked to a virus, and will likely not be the last.

The best known cancer-causing virus is HPV, or human papillomavirus, which can lead to cervical cancer and is the target of two new anti-cancer vaccines, Gardasil and Cervarix, from Merck & Co Inc and GlaxoSmithKline Plc.

Kaposi’s sarcoma, the most common malignancy in AIDS patients and the most common cancer in Africa, is also caused by a virus.