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Compelling evidence for the potential public
health significance of the acute phase of HIV
infection has been gathered among
serodiscordant couples in Rakai, Uganda. These
studies, led by Dr. Maria Wawer of the Columbia
Mailman School of Public Health, showed a
strong correlation between the viral load of
the infected partner and the risk of
seroconversion in the negative partner. A
follow-up study found that the highest rates of
transmission occurred during the earliest stage
of infection, with a rate of 0.0082 infections
per coital act compared to 0.0015 infections
per coital act at 6 to 15 months after
infection. Other studies have corroborated the
finding that the acute phase has an impact on
the expansion of the epidemic out of proportion
with its short duration.
 Rakai, Uganda in orange
Further, there is also growing evidence that
newly infected individuals themselves may also
benefit clinically from prompt intervention,
including studies conducted by Dr. Christine
Hogan and colleagues in the Division of
Infectious Diseases as the Columbia University
College of Physicians and Surgeons. At a
minimum, early knowledge of HIV infection
allows individuals to receive health-promotion
counseling and to have their viral loads,
t-cell counts, and overall health regularly
monitored. There is also the intriguing
possibility that if antiretroviral therapy is
introduced very early after infection, it may
be possible to prevent the early depletion of
significant HIV-specific components of the
immune system that might otherwise be lost
permanently, perhaps resulting in a lowered
"set point" (i.e., reduced viral loads) after
the acute phase. However, the long-term
toxicity and side effects of antiretroviral
regimens still suggest great caution in
initiating drug therapy early after infection.
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Currently,
the HIV Center
along with the
Columbia
University
Center for AIDS
Research
(CU-CFAR) is
participating
in the
multi-site
study
"Understanding
the Social and
Psychological
Context of
Acute HIV
Infection"
sponsored by
NIMH's AIDS
Research
Centers. Along
with
collaborators
at UCLA, UCSF,
UCSD, Yale
University and
the Medical
College of
Wisconsin,
investigators
at the HIV
Center and the
CU-CFAR are
conducting
intensive
quantitative
and qualitative
interviews with
acutely
infected
individuals
(for a total of
60 across the
six sites). The study is designed
to collect narratives from recently infected
people to develop an understanding of how cases
are detected, the social and psychological
context of recent HIV transmissions, and
motivations for behavior change.
"The goal of this whole study is to
determine what an intervention would look like
– what would the content and the process be? What kind of venue? By what kind of person and
at what time point? Of course, in addition to
prevention further transmissions, we also want
to help people cope, maintain their health, and
improve their quality of life," added Remien.
To more closely examine the issue of
detecting new infections, an HIV Center team is
also developing a new initiative with partners
from CBOs and state and local government to
look at the current practice and future
potentials for detecting acute HIV infection in
diverse populations in New York State. In
particular, HIV Center researchers plan to
study and compare two complementary methods for
identifying new HIV infections.
The "medical approach" would require
physicians to recognize symptoms such as fever,
rash, swollen lymph glands, myalgias, and
headache as possible evidence of new HIV
infection and to initiate a inquiry into
recent possible risk behaviors. If warranted,
physicians would then order tests for both the
virus and for antibodies and then intervene
with patients appropriately.
By contrast, the "public health approach"
involves pooling blood samples that have
already tested negative for HIV antibodies in
laboratories and then tested for the presence
of HIV itself. If HIV is detected in these
samples, it would mean that one or more blood
draws was taken from at least one person who is
acutely infected. The pooled samples could be
quickly broken down and re-tested to determine
the case or cases of new infection.
-- by Raymond A. Smith |
