Friday, July 23, 2010

Antibiotics prevent malaria

Preventative malaria "treatment with affordable and safe antibiotics...has the potential to act as a 'needle-free' natural vaccine against malaria", according to a study published in the journal, Science Translation Medicine. This type of treatment "may likely provide an additional valuable tool for controlling and/or eliminating malaria in resource-poor settings."

During research, the multinational team "found that infection with malaria parasites during administration of preventative antibiotics developed a vaccine-like immunity against re-infection."

Approximately one million people die from malaria each year and nearly half of the world's population is at risk of contracting malaria, a mosquito-transmitted parasite. "Only an estimated 10 to 100 parasites per mosquito bite invade the liver where they replicate. About a week after infection, tens of thousands of parasites are released into the bloodstream where they are responsible for malaria's recurring fevers and cause life-threatening complications."

The proposed treatment attacks parasites "during their passage into the liver of the infected host. The "researchers showed that the antibiotics caused a cellular defect in malaria parasites...This action did not prevent parasite replication in the liver but blocked the malaria parasite's fatal conversion to the disease causing blood stage. The very late arrest of parasites in the liver allowed the immune system to mount a robust defense against subsequent infections." In this way, the body produces results that are comparable to vaccines that use weakened varieties of the parasite.

Further reading:
London School of Hygiene & Tropical Medicine (LSHTM) (2010, July 23). 'Needle-free' intervention as natural vaccine against malaria. ScienceDaily. Retrieved July 23, 2010, from http://www.sciencedaily.com­ /releases/2010/07/100723112711.htm

Wednesday, July 14, 2010

Outposts

Ten newly funded projects focus on regions where malaria is currently endemic. After receiving "$14 million in first-year funding from the U.S. National Institute of Allergy and Infectious Diseases (NIAID), 10 new research centers are joining the fight to control and ultimately eliminate malaria worldwide."

Malaria parasites infect about 250 million people each year and cause nearly one million deaths annually. Regions that are most plagued by malaria include parts of Africa, Asia, the Pacific islands, and Latin America. These areas are where the NIAID research centers will do the most good.

"The regions include some of the focus countries of the President’s Malaria Initiative, an effort that since 2005 has worked to fight malaria in parts of the world most affected by the disease."

“One of our primary goals with these centers is to fund cutting-edge research in malaria-endemic areas that will keep up with the rapidly changing epidemiology of the disease,” said NIAID Director Anthony S. Fauci.

Although malaria has already been eliminated from many parts of the world, "40 percent of the world’s population still lives in areas where they are at risk of contracting the disease."

Scientists and medical professionals at these new centers hope to find a way to end malaria. "The centers seek to integrate clinical and field approaches with laboratory-based immunologic, molecular and genomic methods. They will adapt their research to changes in malaria epidemiology and emerging research needs as well as opportunities within specific regions."



Source:
"US Health Institute Funds 10 Global..." America.gov. 09 July 2010. http://www.america.gov/st/scitech-english/2010/July/20100709163404frnedloh0.4317896.html

Friday, July 9, 2010

Antioxidants

Adding "antioxidant therapy to traditional antimalarial treatment may prevent long-lasting cognitive impairment in cerebral malaria", based on research from an experimental mouse model.

"Malaria, an infection caused by parasites that invade liver and red blood cells, is transmitted to humans by the female Anopheles mosquito. Malaria is one of the leading infectious diseases worldwide, affecting more than 400 million people and causing more than 2 million deaths each year, mainly among African children."

Cerebral malaria is a "potentially fatal neurologic complication of infection by the most-feared malarial parasite, Plasmodium falciparum." Cerebral malaria is known to cause life-long memory loss, learning impairment, and language and math deficits. Cognitive damage persists even after the malaria illness is cured.

"Cerebral malaria and its molecular mechanisms are under intense study, but the cognitive dysfunction that can persist in survivors in the aftermath of successful treatment has gone unrecognized until recently," says Guy A. Zimmerman M.D., professor and associate chair for research in the University of Utah School of Medicine's Department of Internal Medicine and a contributor to the study. "This complication may impose an enormous social and economic burden because of the number of people at risk for severe malaria worldwide. Our findings demonstrate that, by using experimental models of cerebral malaria in mice, we can explore mechanisms of cognitive damage and also examine potential treatments for reducing or preventing neurologic and cognitive impairment."

Scientists studied "the persistence of cognitive damage in mice with documented cerebral malaria after cure of the acute parasitic disease with chloroquine, an antimalarial therapy". Zimmerman and his colleagues "determined that impairment in memory skills was still present 30 days after the initial malaria infection. Cognitive deficits that persist for years after the episode of cerebral malaria have also been reported in 11 percent to 28 percent of children who survive the infection."

The researchers believe that "it is possible that the mechanisms for persistent cognitive deficits are independent of those that cause neurological injury and death during acute cerebral malaria". They have been able to "demonstrate that oxidative stress is present in the brains of mice infected with cerebral malaria."

Oxidative stress is an imbalance between the production of reactive oxygen-containing molecules. The imbalance "can damage cell structures and the body's ability to detoxify these molecules or repair the resulting damage."

The research group found that "treating mice with a combination of chloroquine" and antioxidant agents "at the first signs of cerebral malaria prevented both inflammatory and vascular changes in the tissues of the brain, as well as the development of persistent cognitive damage." Furthermore, the antioxidants did not diminish the efficacy of the antimalarial.

Although, antioxidants may not treat malaria directly, they may stave off one of the most dreaded results of enduring cerebral malaria.

Source:
University of Utah Health Sciences (2010, June 28). Antioxidants may help prevent malaria complicaton that leads to learning impairment. ScienceDaily. Retrieved July 9, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100625131416.htm