Investigation of the social network surrounding this case indicates that unsafe, anonymous sex along with the use of drugs, including crystal methamphetamine, remains common. Many of the patient's partners already knew they were HIV-positive, some for many years.

Database matching and laboratory analysis of the potentially related strains is complex, and results of genetic analyses may not be available for weeks or months, says the New York City Department of Health and Mental Hygiene.

The source of the New York City man's infection is still unknown and remains under investigation, the department says.

Although the patient's strain of HIV is highly drug resistant, he reportedly is responding to treatment that includes the two drugs to which his strain appears to be susceptible, as well as other drugs that may be effective.

Resistance to Antiretroviral Drugs Increasing

Health officials have reached most of the named contacts of the patient. Many were previously HIV-infected. Obtaining blood samples for resistance testing, and testing of these samples to determine the genetic relatedness of strains is continuing and may take weeks to months to complete.

The Aaron Diamond AIDS Research Center recently presented findings from a study of a group of men who have sex with men who were tested for HIV between 1999 and 2004, which indicated that more than one quarter of those with recent infection have resistance to one or more drugs. Resistance to any 2 classes of antiretroviral drugs increased from 2.6% in 2000 to 9.4% in 2004.

In summary, there is good news and bad news, and there are many things that we still don't know, say New York health officials.

The Good News

The patient is responding to treatment thus far. This indicates that the strain, while difficult to treat, appears to be treatable at this point. However, the patient remains critically ill and must continue to be monitored closely.

To date, no other patients have been identified with the same strain Through efforts of the Health Department, physicians, laboratories and others, there is now a monitoring system in place to identify similar cases if they occur.

The Health Department has learned from physicians that they are testing patients for this strain of HIV. This means that there is a better chance of identifying additional cases in the coming months and years if they occur.

Community organizations and physicians report an increased discussion of the need for safer sex and HIV prevention.

The Bad News

Many of the patient's partners were anonymous and the Health Department will not be able to reach them. Therefore, they may not be tested for HIV and, if infected, may not be diagnosed for months or years.

Investigation of the social network surrounding this case indicates that unsafe, anonymous sex along with the use of drugs, including crystal methamphetamine, remains common. Many of the patient's partners already knew they were HIV-positive, some for many years. Nevertheless, they had unsafe sex and used drugs. Many had a recent history of other sexually transmitted diseases, such as syphilis and gonorrhea.

Many unsafe sexual encounters occurred in public sex venues and through Internet contacts.

The Unknown

The precise time of this patient's infection, which occurred sometime between 4-20 months prior to his first positive HIV test.

How many other people have similar strains of HIV.

Whether there have been additional patients with this strain who remain undiagnosed.

Whether there will be such cases in the future.

This is a complex investigation and can take months, says the Health Department. Periodic updates will be provided throughout this process.

Public Health Messages

Whether one is HIV negative or HIV positive, safe sex is critical. Medications can lose their effectiveness if resistance occurs. Everyone should practice safe sex. There are several indications that unsafe sexual behavior, especially among men who have sex with men, may be increasing. Nationally, as well as in New York City, syphilis, LGV, and gonorrhea among this population have increased over the past few years.

Doctors caring for HIV-infected people should promote adherence by simplifying regimens and ensuring access to mental health and substance abuse services and housing. People being treated for HIV should adhere to their medication regimen to reduce their viral load and to prevent the development of resistance.

Doctors should routinely offer HIV counseling and voluntary testing, and should consider the diagnosis of acute retroviral syndrome among people who have risk factors for HIV and present with flu-like symptoms: fever, swollen glands, sore throat, rash, muscle aches, diarrhea, headache, nausea and vomiting.

People with acute HIV can be very infectious because they are not aware that they are positive and the viral load (amount of HIV in the blood and body fluids) can be very high during acute retroviral syndrome.

People at risk for HIV should learn their status so that they can access treatment if they are infected and take steps to prevent transmission of the virus to others.