WASHINGTON, Dec. 1 - More people in the United States are
infected each year with the AIDS virus than previously thought,
according to federal health officials, in a finding that could
affect the debate over how much money should be spent on
No one is yet sure whether more people have actually been
infected in recent years or the figures, still undergoing peer
review, are simply a better estimate than the old ones.
For 14 years, the Centers for Disease Control and Prevention used
informal methods to estimate that about 40,000 people annually in
the United States are newly infected with H.I.V. In recent years,
federal officials have worked to set up a more accurate
The numbers from the new system are now in, although the agency
has not released them.
The Washington Blade, a gay newspaper, reported on Nov. 14 that
the new estimates showed infection rates were 50 percent higher
than previously believed, with 58,000 to 63,000 infected in the
most recent 12-month period. The Washington Post and The Wall
Street Journal had similar reports on Saturday.
"We currently have a paper going through a scientific review
process," Tom Skinner, a C.D.C. spokesman, said Saturday, "and
until that process is complete, we're not in a position to say
one way or another whether the numbers will actually be up from
A federal official who would not speak for attribution about the
new numbers because of the review process said they were indeed
higher than the old estimate, but not by as much as The Blade and
The Post reported.
It has been clear for at least a year that the old estimate would
have to be revised upward, said David R. Holtgrave of Johns
Hopkins University, a former director of one of the C.D.C.'s
principal AIDS prevention programs.
From 2001 to 2005, more than 186,000 people in 33 states received
diagnoses of H.I.V. or AIDS, according to figures. That amounts
to more than 37,000 new cases each year from just two-thirds of
"With just a little simple math, you get more than 40,000 new
cases," Dr. Holtgrave said.
Whether the number of infections is higher than previously
believed and whether infection rates are rising are both
politically charged issues.
President Bush has increased financing for AIDS treatment and
prevention programs abroad, but spending for domestic prevention
efforts dropped 19 percent in inflation-adjusted terms from 2002
Julie Davids, executive director of the Community H.I.V./AIDS
Mobilization Project, a national advocacy group, said it planned
to protest Tuesday in front of the C.D.C. headquarters in Atlanta
to demand that the agency release the new figures and step up
prevention efforts. "We don't know whether infection rates are
rising or they've just been higher than we thought," Ms. Davids
said. "But either way, this shows that prevention efforts are
Doctors and states are required to report cases of full-blown
AIDS, but only some states report positive results on tests for
H.I.V. infection to the agency. It takes years for someone who is
infected to develop symptoms; many people have been infected for
years before they are tested.
Under the C.D.C.'s new surveillance system, 19 states and cities
are performing two different blood tests of H.I.V. antibodies -
the first indication of an infection. One test is highly
sensitive and is able to spot an infection even in its earliest
months. The other test is cruder, and patients must nurse an
infection for many months before it can be identified with this
When a blood sample receives a positive result on the first test
and a negative result on the second, officials have decided that
this person was probably infected recently. By adding up these
mixed results and projecting them across the country, the agency
is able to come up with an estimate for new infections.
The agency sent out a letter to scientists on Nov. 26 describing
the new system and urging patience as the numbers are reviewed.
Donald G. McNeil Jr. contributed reporting from New York.