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Search for Origin of New AIDS Strain Widens PDF Print E-mail
Earth News
Sunday, 13 February 2005 14:29
AIDS viruses isolated from two people are being studied to determine whether either might be the source of a rare and potentially more aggressive form of H.I.V. detected in a New York City man, an AIDS scientist involved in the studies said yesterday. Search for Origin of New AIDS Strain Widens

The New York Times
February 14, 2005

AIDS viruses isolated from two people are being studied to determine whether either might be the source of a rare and potentially more aggressive form of H.I.V. detected in a New York City man, an AIDS scientist involved in the studies said yesterday.

Many more tests need to be conducted to determine if the strains from the three people are the same, said the scientist, Dr. David Ho. He directs the Aaron Diamond AIDS Research Center in Manhattan, which is conducting some of the studies in collaboration with the New York City health department. While some findings may be available in a week, others will take longer, Dr. Ho said in an interview.

Even if the strains prove to be the same, that would not necessarily mean that a supervirus is on the loose, since there could be genetic factors in the first man that would make his infection progress faster.

"What we can't prove is that this is a supervirus" and that it caused the rapid progression from infection to AIDS in the New York City man, Dr. Ho said.

Laboratory tests in Dr. Ho's laboratory and elsewhere have shown that the strain from the man whose case started the investigation is resistant to 19 of the 20 licensed anti-retroviral drugs. AIDS experts said that the strain might have led to the rapid onset of AIDS in the man or that his immune defenses might have been weakened by drug use or genetics.

Molecular tests of the man's H.I.V. show it has changes that appear to differ significantly from the typical strains being circulated in New York City, and precisely what those changes mean remains to be determined, Dr. Ho said.
Dr. Ho said his laboratory has begun testing a virus that was isolated from a man who was known to be H.I.V.-infected before he became a sex partner of the New York City man.

That partner probably had sex with the New York City man in October, a few weeks before the New York City man became ill with what his doctors believe was the acute retroviral syndrome. It occurs in the earliest stages of H.I.V. infection.

The partner is "a potential source for this man's case," Dr. Ho said. "But he may not be."

The second virus is from an unidentified patient in San Diego who was apparently infected before the New York City man. It was found by scouring the records of a commercial laboratory, ViroLogic Inc. of South San Francisco, and portions of its genetic makeup closely resemble the molecular pattern of the New York City man's virus, Dr. Ho said.

Dr. Ho's team sent the partner's virus to ViroLogic for testing. Doctors from around the country send thousands of H.I.V. specimens to the company for testing.
An additional man who was a sex partner of the New York City man has declined to participate in the epidemiologic investigation, Dr. Ho said. It is not known if he is H.I.V.-infected.

The two male contacts in New York City, only one of whom is cooperating with the investigation, are among hundreds of men with whom the New York City man told health officials he has had sex in recent weeks while using crystal methamphetamine. The New York man who sparked the investigation is cooperating with city health officials but apparently does not know the names of all his partners.

The health department is trying to trace as many of his sex contacts as can be ascertained. To protect his privacy, health officials have identified him only as in his mid-40's.

So far, city health workers have reached "about a dozen" of the man's contacts, said Sandra Mullin, director of communications for the health department. She said she did not know how many contacts have agreed to donate specimens for testing and, if so, what the findings were.

Officials of the Centers for Disease Control and Prevention, a federal agency in Atlanta, said that they have notified health departments elsewhere. While the agency is aiding in the investigation, the city is taking the lead, said Dr. Ronald O. Valdiserri, the director of H.I.V./AIDS prevention at the agency.

On Friday, Dr. Thomas R. Frieden, the commissioner of the New York City Department of Health and Mental Hygiene, said the man's case was the first in which a strain of H.I.V. had been found that showed both resistance to multiple classes of drugs and apparently led to a rapid progression from infection to AIDS. Each component has been reported earlier.

Dr. Frieden and other AIDS experts said they considered it prudent to investigate what they knew was only one case and to issue an alert to doctors and hospitals to seek other cases.

Dr. Frieden was joined by other AIDS experts at a news conference that he said was intended to issue a wake-up call to the public and health professionals about the seriousness of unsafe sex and the apparent increase in drug-resistant H.I.V. strains.

While the experts said that they could not rule out the possibility that they were dealing with an extraordinary confluence of two rare events, they also said they were concerned about the possibility of the man passing it to his hundreds of sexual contacts.

"You need a mechanism to do that, and this is what the city is doing in tracing contacts," Dr. Ho said.

The health department asked doctors and hospitals for their help because the city, like most other areas of the country, has no system to monitor the occurrence of H.I.V. drug resistance among recently infected people.

So, Dr. Frieden said, the city has no easy way to determine whether such a strain was an isolated event or whether it was infecting a cluster of people, small or large.

Dr. Frieden and other experts said that logically there had to be at least one other individual with the rare strain who gave it to the New York City man.

Some scientists criticized the health department for causing unnecessary alarm by disclosing information about just one case, and for calling a news conference when it had to say the scientific premise for its announcement was weak.

Dr. Frieden defended his department's decision to issue a warning on Friday.
"Everyone who hears this, their first thought is either it can't be true or, if it is, it can't be that significant," Dr. Frieden said in an interview. "But the more you hear about it, the more concerned you become."

He said that the decision to go public was not easy and was not taken lightly, but that, given the evidence he had available, he had no doubt they did the right thing.

As he cautioned on Friday, several things remain unknown. They do not know how widespread this strain is or how widespread it will become. They also do not know how this patient will fare.

But they do know several troubling things beyond a doubt, he said.

"There is not a question that drug resistance is on the increase," he said. In addition, he said, there is no good system in place to track patient adherence to drug treatment. That, paired with the fact that there is far too much risky sex taking place in which methamphetamine use plays a role, is enough to give anyone pause.

"One of our really core values is that we take a great deal of care and pride in what we say," Dr. Frieden said. "We don't go out and say things unless we have reasonable certainty that what we say is correct."

He said that anyone who suggests that the department issued the warning simply to scare the public into behaving more responsibly was absolutely wrong.

Dr. Ho acknowledged that it was extraordinary for the health department to issue an alert before the full scientific information was available or made public. But Dr. Ho said he and other scientists were doing the very tests that critics said had not been performed.

"A lot of people are asking for data that we either have not disclosed or we are working on," Dr. Ho said. "It could be that the man is genetically prone to have a rapid progression," Dr. Ho said.

Marc Santora contributed reporting for this article.

Copyright 2005 The New York Times Company
Last Updated on Sunday, 13 February 2005 14:29

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