July 31, 2006

DDT returns to battle malaria in Africa

NEW YORK (Reuters Health) - Controlled indoor spraying of
the infamous pesticide DDT is poised to make a comeback in
countries that have tried and failed to do without it in the
battle against malaria, according to a special news feature in
the journal Nature Medicine.

Malaria is caused by a parasite known as Plasmodium, which
is usually transmitted to humans through the bite of an
infected mosquito.

Apoorva Mandavilli, senior news editor of the science
journal, notes in the article that DDT -- short for
dichlorodiphenyl-trichloro ethane -- is known to be very
effective against malaria and helped rid the United States of
the disease in the late 1940s.

In the 1950s and 1960s, the Global Malaria Eradication
Campaign relied heavily on DDT to control malaria globally. It
was used not only in the US but also in Europe, India, Africa
and South America, where it dramatically cut malaria rates and
saved millions of lives.

Beginning in the 1970s however, the US and several European
countries banned DDT, fearing it may harm the environment and
get into the food chain, leading perhaps to illness. African
governments were also pressured to abandon DDT for malaria
control and most did.

Today, malaria kills as many as 1 million people each year,
about 90 percent of them in sub-Saharan Africa. "Someone dies
of malaria every 30 seconds - and most of those are pregnant
women and children under the age of five," Mandavilli notes.

On May 2, the United States Agency for International
Development (USAID), endorsed indoor spraying of DDT to rid
homes of malaria-carrying mosquitoes. "The World Health
Organization is set to follow," Mandavilli reports.

"In its new guidelines, a final version of which is
expected to be released later this summer, the WHO is
unequivocal in its recommendation of DDT for indoor residual
spraying," Mandavilli further reports.

Evidence suggests that controlled spraying a small amount
of DDT on the inside walls and eaves of houses where mosquitoes
rest -- as opposed to aerial spraying on crops and villages as
was done in the past -- can have a big impact in the fight
against malaria with a low risk of harmful effects on the
environment and on human health.

SOURCE: Nature Medicine, August 2006.