News from the 10th
Conference on Retroviruses and Opportunistic Infections (CROI),
the most important HIV medical conference held in the U.S.,
held this year in Boston in February. Visit www.retroconference.org
for more information.
Super-shedders
HIV in genital secretions
might increase the risk of transmission. British researchers
called some men “seminal super-shedders” because of the unusually
high amount of virus found in their semen (actually, their
“seminal plasma”).
They wrote that usually viral
load in semen is found less frequently, and at lower levels,
than in the blood. The study looked at the semen of men who
were not on therapy and had a viral load greater than 400.
The majority, 58% of the 73 men, had detectable virus in their
semen, but not higher than that found in their blood. A third
had a seminal viral load less than 400. (This doesn’t mean
the virus wasn’t there—it might need to be measured differently,
such as using tissue samples.)
This left 12% (nine men)
who were super-shedders. Even though their blood viral load
was not statistically different from that of the other shedders
(the majority group), their semen viral load was significantly
higher. Their T-cell counts and AIDS status were also the
same as that of the other shedders.
The technology used to measure
viral load throughout the body is not available in clinics.
Therefore, people may be at greater risk of transmitting HIV
without knowing it.
Vaginal shedding
U.S. researchers found that
sub-clinical inflammation (no symptoms or disease) was associated
with increased HIV shedding in the vagina, no matter what
a woman’s viral load was. As with men, this shedding may increase
the risk of transmission. They said the finding helps explain
transmission despite having a low viral load in the blood.
Previously the researchers had found that low viral load in
the blood was associated with low shedding in the vagina (and
vice versa), and that pro-inflammatory cytokines (a type of
cell) associated with cervical ulcers increase shedding. The
study looked at 60 vaginal samples.
Protection against HIV
Researchers found that a
virus discovered about 10 years ago may protect people with
HIV against disease progression and death. GBV-C is closely
related to hepatitis C virus. Researchers found that men co-infected
with GBV-C had an 80% survival rate, while the guys who weren’t
had a 36% survival rate. However, the survival for the men
who had been infected with GBV-C but had cleared the virus
was only 16%. The study looked at stored blood samples over
a 10-year period from 271 men in MACS (Multicenter AIDS Cohort
Study).
Another group of researchers
reported that GBV-C in the test tube almost completely suppresses
HIV. The idea of infecting HIV-positive people with GBV-C
to protect them is tantalizing, but can’t be considered until
the mechanisms and dangers are understood. The advantage of
continuous infection was compared to having an extra 300 T-cells.
GBV-C hasn’t been found to cause any symptoms of disease,
another reason why it’s intriguing as a weapon for people
with HIV.
Six months
Researchers looked at data
from 13 cohorts (groups of patients). Just getting T-cells
above 25 after six months of therapy cut the risk of death
in half. Overall, where people are at six months after starting
therapy was more closely related to survival than where they
were when they started. Researchers concluded that, “It matters
where you are, not where you came from!”
EuroSIDA—surviving
Thanks to therapy, deaths
related to HIV/AIDS were cut by 10% for each six-month period
after September 1998. So was the development of AIDS itself.
Doctors gathered the information from a European database
of 8,551 patients. They found that even people with less than
20 T-cells had a significantly greater survival in the HAART
era (highly active antiretroviral therapy) than before it.
More AIDS cases
AIDS cases went up one percent
between 1999 and 2001, the first increase since 1993.
HIV infection also went up,
by 8% for the 25 states that report HIV cases. HIV went up
by 10% among heterosexuals and 14% among gay men. These numbers
did not include states with large numbers of HIV-positive
people, like New York and California.
Officials from the U.S. Centers
for Disease Control and Prevention (CDC), who reported the
findings, said that
- Approximately 1/3 of 900,000
people with HIV in the U.S. are unaware of their infection,
increasing the risk of transmission.
- Medical providers should make
rapid HIV testing more routine so that infections are found
more quickly.
- More counseling is needed for
people who know that they’re positive.
CDC researchers also listed
possible reasons for increased risk-taking. These include
the sense that effective therapy is lowering fear of infection
and lack of first-hand knowledge or memory of the “dark days”
when people often died.
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