WASHINGTON — Preliminary findings from a new study of AIDS infection among intravenous drug abusers in four U.S. cities show that Los Angeles has a "very low" rate of infection--"nothing like that of New York City"--even though its addict population is only slightly smaller, federal health officials said Friday.
Officials from the National Institute of Drug Abuse, which sponsored the study, said at a news conference that they could not explain the disparity in the numbers, though they speculated that the AIDS virus began spreading in the New York drug community earlier than in Los Angeles.
"Also, 'shooting galleries' are much more common in New York City than in Los Angeles, which may be one of the factors," said Dr. Roy Pickens, director of the institute's division of clinical research, referring to sites where addicts buy and use narcotics and often share hypodermic needles.
Worst Area to Date
Charles R. Schuster, director of the institute, said that data obtained between March and September from 581 intravenous drug abusers in drug treatment programs in New York, Los Angeles, central New Jersey and San Antonio showed that "New York remains the most seriously affected area to date."
New York had a 57% rate of infection, while the rate in Los Angeles was only 2.8%. In New Jersey, the rate was 39%, while in San Antonio it was zero, Schuster said. The ongoing study eventually will include information from Miami and Baltimore, as well as four more cities to be added by next year, he said.
Pickens cautioned, however, that the study examined only addicts who were undergoing treatment and noted that because "most addicts are not in treatment, we suspect (the rates) are much higher." Further, he said, additional studies conducted by others in Los Angeles have reported rates as high as 6%.
Different Parts of Town
"We may be going into different areas of the city than these other programs," Pickens said, adding that federal health officials are compiling every available study of infection among intravenous drug users to get a more accurate picture.
"Data like this will be better when we get all the studies and put them together," he added.
Pickens said that federal officials want "to establish a monitoring system where we go into the same places every six months over a period of years. That way, we will better know what the trends are. We wouldn't want to say that the rates in Los Angeles are increasing or decreasing or remaining the same until we are comfortable with the data."
He said: "But we can say this: the rates are very low in Los Angeles--nothing like that in New York City. Los Angeles has a large (intravenously) drug-abusing community--but it's not quite as large as New York's."
Schuster said that the latest findings are similar to those from other institute studies reported at the third annual International AIDS Conference here in June. Those studies, covering 1,770 intravenous drug abusers, showed a 61% infection rate in New York; a 1.5% rate in Southern California; 29% in Baltimore; 5% in Denver; 2% in San Antonio; and zero in Tampa, Fla..
Schuster said it is "important to realize that (AIDS infection) in the population of (intravenous) drug abusers has shown rapid increases over time."
A 1985 New York study of intravenous drug users--men and women who had earlier enrolled in a study on chronic liver disease--showed that none were infected in 1978, when their blood was first stored, Schuster said. Blood samples taken in 1979 and later tested showed that 29% were infected, he said. By 1984, Schuster said, the figure had climbed to 56%.
Federal health officials have estimated that there are between 1.1 million and 1.3 million intravenous drug abusers in the United States, about one-third of them believed to be in New York City. They have also estimated that 300,000 have already become infected with the virus.