Potential for malaria transmission higher than previously thought

Feb 20, 2007

Each year, malaria results in more than a million deaths. Controlling this disease involves understanding its transmission, and understanding its transmission means understanding its basic reproductive number, R0. For all infectious disease, R0 describes the most important aspects of transmission as it is the expected number of hosts that can trace their infection directly back to a single host after one disease generation. For vector-borne diseases, such as malaria, R0 is given by a classic formula.

In a new study published in PLoS Biology, David Smith and colleagues demonstrate that estimates of R0 range from around one to over 3,000, providing much higher estimates than previously thought, with serious implications for the control of the disease.

The author provides 121 estimates of R0 for Plasmodium falciparum malaria in African populations. In addition to the higher estimates of R0, they also show that in small human populations, R0 approximates transmission when counting infections from mosquito to mosquito, but overestimates it from human to human. Previous studies showed that transmission is amplified if some humans are bitten more than others. The authors confirm that such heterogeneous biting amplifies transmission counting from mosquito to mosquito, but it can also dampen transmission counting from human to human. Humans who are bitten most both infect a large number of mosquitoes and absorb many infectious bites.

What does this mean for control? When R0 is in the thousands, eliminating malaria may seem impossible. If transmission from the humans who are bitten the most can be targeted, however, local elimination can still be within reach.

Source: Public Library of Science

Explore further: 'Ebola will return', veteran scientist warns

Related Stories

EPA says first day of oil spill spent 'planning'

4 hours ago

On the afternoon of the largest coastal oil spill in California in 25 years, graduate student Natalie Phares quickly organized a volunteer bucket brigade to clean a beach north of Santa Barbara.

Insect mating behavior has lessons for drones

4 hours ago

Male moths locate females by navigating along the latter's pheromone (odor) plume, often flying hundreds of meters to do so. Two strategies are involved to accomplish this: males must find the outer envelope ...

Recommended for you

'Ebola will return', veteran scientist warns

4 hours ago

Congolese expert Jean-Jacques Muyembe may be little known to the public, but he has been one of the world's top Ebola investigators since the first epidemic erupted in central Africa in 1976.

Score IDs patients with upper extremity DVT at low risk

19 hours ago

(HealthDay)—For patients with upper-extremity deep vein thrombosis (DVT), six easily available factors can be used to create a score that identifies those at low risk of adverse events during the first ...

Combined drug treatment combats kidney disease

May 29, 2015

A recent discovery by drug researchers whereby coupling specific cell membrane receptors has altered kidney cell function has triggered a re-think of how to treat chronic kidney disease (CKD) more effectively.

Active substance targeting dreaded hospital germs

May 29, 2015

In the German Center for Infection Research (DZIF), scientists have conducted clinical studies on an active substance against the dreaded hospital pathogen Staphylococcus aureus: a highly effective protein from bacteriophages ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.