Climate to widen sleeping sickness risk to southern Africa

Sleeping sickness could threaten tens of millions more people as the tsetse fly which transmits the disease spreads to southern Africa as a result of global warming, a study published on Wednesday says.

By 2090, an additional 40 to 77 million people could be at risk of exposure to the disease, the study concludes. Currently 75 million people live within its range.

The scientists base the estimate on how the tsetse and the Trypanosoma parasite it carries are likely to respond to rising temperatures in coming decades.

At present, 70,000 cases of sleeping sickness, also called trypanosomiasis, occur each year in eastern, central and western Africa, according to the (WHO).

The parasite is transmitted from cattle to humans by the tsetse when it takes a blood meal. It is fatal without treatment, causing convulsions and serious sleep disturbance that lead to coma and death.

Scientists led by Sean Moore of the US Centers for Disease Control and Prevention (CDC) carried out a computer simulation in line with two scenarios laid out by UN climatologists in 2007, predicting warming of 1.1-5.4 degrees Celsius (2.0-9.7 degrees Fahrenheit) depending on .

The team looked at the strain of parasite that is prevalent in East Africa and the two tsetse species which carry it.

Outbreaks of the disease can occur when mean temperatures are between 20.7 C to 26.1 C (69.25 F to 79 F), they found.

Some parts of eastern Africa will become too hot for tsetse larvae to survive. But other areas in this region, as well as in southern Africa, that were previously too cool will become a potential home for it.

The study, appearing in the Journal of the Royal Society Interface, adds to previous research into the link between disease and .

In 2008, the US identified a "deadly dozen" of diseases that could spread into more temperate areas through mosquitoes, parasites or pathogen-laden water.

They include malaria, cholera and yellow fever as well as sleeping sickness.

add to favorites email to friend print save as pdf

Related Stories

Fly gut bacteria could control sleeping sickness

May 11, 2010

A new bacterial species, found in the gut of the fly that transmits African sleeping sickness, could be engineered to kill the parasite that causes the disease. The study, published in the International Journal of Systematic an ...

Revealing secrets of 'African sleeping sickness'

Oct 27, 2008

Scientists in the United Kingdom and Russia are reporting identification of a long-sought chink in the armor of the parasite that causes African sleeping sickness, a parasitic disease that kills at least 50,000 people each ...

Recommended for you

Where Ebola battles are won

8 hours ago

(HealthDay)—Four hospitals that are home to advanced biocontainment facilities have become America's ground zero in the treatment of Ebola patients.

Depression tied to worse lumbar spine surgery outcomes

10 hours ago

(HealthDay)—Depressive symptoms are associated with poorer long-term outcome in patients undergoing surgery for lumbar spinal stenosis (LSS), according to research published in the Oct. 1 issue of The Sp ...

Ebola death toll edging to 4,900 mark: WHO

11 hours ago

The death toll in the world's worst-ever Ebola outbreak has edged closer to 4,900, while almost 10,000 people have now been infected, new figures from the World Health Organization showed Wednesday.

US to track everyone coming from Ebola nations

11 hours ago

U.S. authorities said Wednesday that everyone traveling into the U.S. from Ebola-stricken nations will be monitored for symptoms for 21 days. That includes returning American aid workers, federal health employees ...

User comments