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SCIENCE &
TECHNOLOGY |
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Prof. Aaron Baba, Special
Advicer on Technological
Development |
Site Powered by Directorate of
Science & Technology, Kogi State |
Updated
November 30, 2008
VOL. 13 No. 747 WEDNESDAY
SEPTEMBER 17 - TUESDAY SEPTEMBER
22, 2008 ISSN 1116 - 7085 N70.00 |
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HIV’s
Spread Declines in Africa —UN
THE number of young people
infected with HIV in Africa
is falling in 16 of the 25
countries hardest hit by the
virus, according to a new
report by a U.N. agency. The
number of young people
infected with HIV dropped by
at least 25 percent in a
dozen countries, the U.N.
AIDS report said. In Kenya,
for instance, the infection
rate among people aged 15 to
24 fell from about 14
percent in 2000 to 5.4
percent in urban areas.
The drop in HIV rates
coincided with a change in
sexual behavior, like having
fewer sexual partners or
increased condom use, UNAIDS
said. But the agency could
not say the drop was because
of recent U.N. policies,
which mainly have focused on
buying AIDS drugs rather
than preventing infections.
Prevention will remain a key
investment for the Bill &
Melinda Gates Foundation,
its co-leader, Microsoft
Corp. founder Bill Gates,
said Tuesday. He spoke in a
conference call with
reporters to preview
comments he’ll make at next
week’s International AIDS
Conference in Vienna.
Gates repeatedly cited
circumcision to reduce the
spread of HIV as an area the
foundation had “got out in
front of” and would continue
to support. Economic woes
have limited how much money
countries can spend on AIDS,
so more must be done to trim
administrative costs and
make delivering treatment as
efficient as possible, Gates
said.
“We’ve hit some limits and
we’re going to have to get
as much as we can out of the
funding that exists,” he
said.
The Seattle-based foundation
has given more than $2.2
billion to fight HIV around
the world, plus $650 million
to support the Global Fund
to Fight AIDS, tuberculosis,
and malaria. The UNAIDS
research provides further
evidence the AIDS outbreak
peaked more than a decade
ago and that the disease is
on the decline. In a report
last year, the agency said
the number of people
infected with HIV had
remained unchanged — at
about 33 million — for the
last two years.
The new report is based on
population surveys and
mathematical modeling, and
comes with a significant
margin of error.
Some experts said the new
focus on prevention was too
little, too late.
“Thanks to the U.N.’s
strategic blunder, many more
people are now infected than
would have otherwise been
the case had they focused on
prevention much earlier,”
said Philip Stevens, a
health policy expert at
International Policy
Network, a London-based
think tank. UNAIDS also
called for more money to
combat the epidemic.
In 2008, the world spent
more than $15 billion on
AIDS, with about half of
that coming from the United
States. In its report,
UNAIDS said that “what’s
been good for the AIDS
response has been good for
global health in general.”
But a study published last
month found there was little
correlation between U.S.
money spent on AIDS and
improvements in other health
areas across Africa.
UNAIDS urged countries to
invest more in their own HIV
programs. It noted South
Africa and Nigeria, two of
Africa’s wealthiest
countries, receive the most
money from international
donors.
Stevens said that while some
recent AIDS investments —
like putting more people on
drugs — have clearly saved
lives, it also has distorted
health spending. Despite
only causing 4 percent of
deaths, AIDS gets about 20
cents of every public health
dollar.
“The same amount of money
that we spend on AIDS could
save many, many more lives
more cheaply by vaccinating
children or distributing
cheap treatments for
diarrhea,” he said.
“Aid agencies have a
responsibility to ensure
they save the most lives
possible with the amount of
money they have available,”
he said. “Spending the
lion’s share on HIV clearly
does not do that.”
Gel Cuts HIV Transmission
Rate
A new topical gel has shown
promise in helping to
protect women from HIV
infection, according to a
study being presented at the
International AIDS
Conference in Vienna,
Austria.
The gel contains the
antiretroviral drug
tenofovir, which keeps the
virus from multiplying.
An effective vaginal
microbicide such as this
could be a major new tool in
the HIV toolbox.
“Women represent the
majority of new HIV
infections globally, and
urgently need methods they
can control to protect
themselves from infection,”
said Dr. Kevin Fenton,
director of the National
Center for HIV/AIDS, Viral
Hepatitis, STD and TB
Prevention, part of the
Centers for Disease Control.
The two-and-a-half-year-old
CAPRISA trial followed
nearly 900 HIV-negative,
sexually active South
African women between ages
18 and 40 to determine how
safe and effective tenofovir
gel was in preventing HIV
infection.
Researchers found the gel
overall reduced infection by
50 percent after a year and
39 percent after 30 months.
In women who used the drug
consistently infection was
reduced 54 percent. The gel
was used up to 12 hours
before and within 12 hours
of sexual intercourse. The
study found the gel also
reduced the risk of genital
herpes by 51 percent.
This is the first completed
study on an antiretroviral
microbicide. In the
double-blind, randomized
control trial, half the
women got tenofovir gel and
half got a placebo.
Information from this trial
could help researchers
develop more
antiretroviral-based
microbicide drugs in the
future.
Antiretrovirals can prevent
retroviruses like HIV from
reproducing and damaging the
immune system.
A separate study presented
at the conference found that
a microbicide that is 40 to
50 percent effective could
prevent nearly 300,000 to
600,000 new infections in a
10-year period.
Tenofovir is marketed by
Gilead Sciences under the
trade name Viread. It
belongs to a class of drugs
called reverse transcriptase
inhibitors. They don’t kill
the virus but they slow down
its growth, which ultimately
slows the progression of the
disease.
The therapy is not yet ready
for widespread use, but the
finding is a giant step
forward in the use of
microbicides, said Dr.
Anthony Fauci, director of
the National Institute of
Allergy and Infectious
Diseases at the National
Institutes of Health.
Mushrooms kill 400 in China
Every year during the height
of the rainy season,
villagers of all ages in a
corner of southwestern China
would suddenly die of
cardiac arrest.
No one knew what caused
Yunnan Sudden Death
Syndrome, blamed for an
estimated 400 deaths in the
past three decades.
After a five-year study, an
elite investigative unit
from China’s Center for
Disease Control and
Prevention believes it has
pinpointed the cause: an
innocuous-looking mushroom
known as Little White.
The search for the culprit
took investigators to remote
villages spread over the
rural highlands of Yunnan
province, said Robert
Fontaine, an epidemiologist
with the U.S. Centers for
Disease Control and
Prevention.
There was “this very obvious
clustering of deaths in
villages in very short
periods of time in the
summer,” said Fontaine, who
helped in the investigation.
“It appears that there was
something a little different
going on.”
Local health officials had
noted the deaths for years.
In 2004, they appealed to
Beijing for assistance. The
government gave the task to
the China Field Epidemiology
Training Program, a unit of
medical investigators at
China’s CDC assigned some of
the country’s toughest
health mysteries.
The medical teams
encountered obstacles. Many
villagers communicated in
their own dialect. Villages
were scattered in often
remote areas. Rapid burials
made it difficult to conduct
autopsies. Torrential rain
and mudslides hampered
travel.
But that first year,
investigators were able to
narrow the list of
possibilities: most victims
had drunk surface water,
they had emotional stress
and they ate mushrooms.
The investigators zeroed in
on mushrooms, because the
deaths were closely aligned
with the harvesting season.
More than 90 percent of the
deaths occurred in July or
August. By the end of 2005,
investigators began issuing
warnings to some villages to
avoid eating unfamiliar
mushrooms.
That was a difficult order
to follow. Yunnan province
is legendary for its wide
variety of wild mushrooms,
many of which are exported
at high prices. Entire
families go out to hunt for
them during the summer
months.
By 2008, investigators had
discovered a relatively
unknown mushroom in a number
of homes where people had
died. The mushroom is not
usually sold in the markets,
because it’s too small.
“We repeatedly found it at
all these sites,” Fontaine
said.
A public information
campaign to warn against
eating the mushrooms has
dramatically reduced the
number of deaths. Only a
handful have been reported
in the last couple of years,
and none so far this year.
However, the mystery has not
yet been definitively
solved. Testing found the
mushroom contained some
toxins, though not enough to
be deadly. Chinese
scientists need to isolate
the toxin and test whether
it triggers cardiac arrests.
Researchers have
hypothesized that there is a
second agent. Many of the
victims showed high levels
of barium, a heavy metal in
the soil that seeps into
mushrooms.
“There is a lot of work left
to do,” Fontaine said. “We
really need additional lab
investigations.”
Problems with poisonous
mushrooms are common
throughout Asia, said
Diderik De Vleeschauwer, a
spokesman for the U.N. Food
and Agriculture Organization
regional office in Thailand.
“Normally we expect people
to have knowledge of what
they can and can’t eat. One
would think there is
indigenous knowledge
available about what they
can forage,” he said. “But
these are accidents that can
happen.”

Rolake Odetoyinbo,
HIV-positive, celebrating
robust existence
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