Featured Research

from universities, journals, and other organizations

Discovery Of Variations In Resistance To Sulfadoxine Across Africa

Date:
April 18, 2009
Source:
London School of Hygiene & Tropical Medicine (LSHTM)
Summary:
Researchers have discovered that malaria parasites in east and west Africa carry different resistance mutations, which suggests that the effectiveness of sulfadoxine as an antimalarial drug may vary across Africa.

Researchers have discovered that malaria parasites in east and west Africa carry different resistance mutations, which suggests that the effectiveness of sulfadoxine as an antimalarial drug may vary across Africa.

Related Articles


The findings have implications for the manner in which malaria control campaigns are carried out, and suggest that coordinating efforts between parts of Africa that share similar patterns of resistance is likely to be more effective than working in isolation in each country.

Plasmodium falciparum (P. falciparum) a mosquito-borne parasite that causes malaria, kills nearly one million people a year, mostly in sub-Saharan Africa. Until recently, treatment in Africa relied on chloroquine and sulfadoxine-pyrimethamine. Unfortunately, parasites have developed resistance to both these drugs by acquiring ‘resistance mutations', genetic changes that prevent the drugs from killing them.

Scientists have discovered that the mutations that caused resistance to chloroquine and pyrimethamine originated in Asia and spread into Africa in the late 1970s and early 1980s respectively. These mutations are now common across Africa and it is no longer possible to determine how they spread across the continent. However, the mutations that cause resistance to sulfadoxine only began to emerge in the mid-1990s, and have not yet spread evenly across Africa.

A study published today in PloS Medicine, and led by Dr. Cally Roper of the London School of Hygiene & Tropical Medicine, used genetic methods to characterise how resistance to sulfadoxine has spread across Africa, with a view to determining its geographical origins in order to help improve measures aimed at controlling the spread of drug-resistant P. falciparum.

The team analysed blood samples collected from patients with malaria in various African countries, and searched the scientific literature for other similar studies. They discovered five major variant genetic sequences (three of which contain mutations that confer various degrees of resistance to sulfadoxine in laboratory tests) to be present in Africa, each with a unique geographical distribution. In particular, the data showed that malaria parasites in east and west Africa carry different resistance mutations.

The findings show that sulfadoxine-resistant parasites have emerged independently at multiple sites in Africa, and that the molecular basis for sulfadoxine resistance is different in east and west Africa. This latter result may have clinical implications because it suggests that the effectiveness of sulfadoxine as an antimalarial drug may vary across the continent. They also suggest that economic and transport infrastructures may have played a role in governing recent parasite dispersal across the continent through their influence on the volume of human migration.

Dr. Roper comments: ‘Our findings suggest that the effectiveness of sulfadoxine as an antimalarial drug may vary across Africa. They also point to the need to co-ordinate malaria control campaigns across socioeconomically linked areas in Africa, rather than focusing solely on national territories, in order to more effectively reduce the malaria burden in the continent'.


Story Source:

The above story is based on materials provided by London School of Hygiene & Tropical Medicine (LSHTM). Note: Materials may be edited for content and length.


Journal Reference:

  1. Pearce et al. Multiple Origins and Regional Dispersal of Resistant dhps in African Plasmodium falciparum Malaria. PLoS Medicine, 2009; 6 (4): e1000055 DOI: 10.1371/journal.pmed.1000055

Cite This Page:

London School of Hygiene & Tropical Medicine (LSHTM). "Discovery Of Variations In Resistance To Sulfadoxine Across Africa." ScienceDaily. ScienceDaily, 18 April 2009. <www.sciencedaily.com/releases/2009/04/090413204550.htm>.
London School of Hygiene & Tropical Medicine (LSHTM). (2009, April 18). Discovery Of Variations In Resistance To Sulfadoxine Across Africa. ScienceDaily. Retrieved October 30, 2014 from www.sciencedaily.com/releases/2009/04/090413204550.htm
London School of Hygiene & Tropical Medicine (LSHTM). "Discovery Of Variations In Resistance To Sulfadoxine Across Africa." ScienceDaily. www.sciencedaily.com/releases/2009/04/090413204550.htm (accessed October 30, 2014).

Share This



More Health & Medicine News

Thursday, October 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Fauci Says Ebola Risk in US "essentially Zero"

Fauci Says Ebola Risk in US "essentially Zero"

AP (Oct. 30, 2014) NIAID Director Anthony Fauci said the risk of Ebola becoming an epidemic in the U.S. is essentially zero Thursday at the Washington Ideas Forum. He also said an Ebola vaccine will be tested in West Africa in the next few months. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Nurse Defies Ebola Quarantine With Bike Ride

Nurse Defies Ebola Quarantine With Bike Ride

AP (Oct. 30, 2014) A nurse who vowed to defy Maine's voluntary quarantine for health care workers who treated Ebola patients followed through on her promise Thursday, leaving her home for an hour-long bike ride. (Oct. 30) Video provided by AP
Powered by NewsLook.com
Microsoft Launches Fitness Band After Accidental Reveal

Microsoft Launches Fitness Band After Accidental Reveal

Newsy (Oct. 30, 2014) Microsoft accidentally revealed its upcoming fitness band on Wednesday, so the company went ahead and announced it. Video provided by Newsy
Powered by NewsLook.com
Bracing to Meet a Killer: Aid Workers Prep for Ebola in Geneva

Bracing to Meet a Killer: Aid Workers Prep for Ebola in Geneva

AFP (Oct. 30, 2014) At the International Federation of Red Cross and Red Crescent Societies, around 30 doctors, nurses, lab technicians and water and sanitation workers are gathered for a crash-course in how to safely deal Ebola. Duration: 01:31 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins