Malaria Vaccine Offers New Prevention Methods

If you have ever traveled to a densely tropical area, you have probably taken anti-malaria medications. You probably also know that protecting yourself from the disease isn’t a piece of cake. My earliest childhood memories of living in Central America included a battery of shots that protected us from everything from typhus to yellow fever. When it came to shielding us from the bite of a malaria-borne mosquito however, protection was a bit more complex, and involved a regimen of either weekly or daily medications that served as a protective shield from the potentially fatal effects of the disease.

And since it depended upon good memory skills and sometimes the right immune system, the doses weren’t always 100 percent effective in warding off the disease. Although none of my family contracted it, we knew scientists and researchers who, even with their acute instincts for regimen, still ended up contracting malaria.

But the real problem today with anti-malaria meds isn’t the chance that they won’t work, but that the majority of the victims aren’t able to afford a lengthy prescription. That’s because most people who contract malaria aren’t incidental travelers from North America who are on a business trip or an excursion to see the local sights, but residents who would never be able to afford the cost of lifelong prescriptions.

According to the World Health Organization, of the more than 2 billion people living in malaria-infested areas, as many as 1 million die each year. Most are children. In sub-Saharan Africa, say researchers Vasee Moorthy and Adrian VS Hill, malaria plays a significant role in infant and maternal mortality. The chronic nature of malaria infections means that even if the patient lives, the illness often impacts the person’s ability to hold a job or provide support for his or her family. According to United Nations International Children’s Fund (UNICEF), infants born to women with malaria are often underweight, heightening the chance for further disease, health problems or early death.

“The socio-economic prospects for malaria-endemic countries may be linked closely to the disease burden of malaria,” say the authors.

So developing a vaccine against this destructive disease has been considered a priority by the medical community as well as by aid and governmental agencies. As Moorthy and Hill point out, meeting that challenge has been difficult because until recently options that were used in other types of vaccines, such as live, attenuated or inactivated sources, couldn’t be used in malaria vaccines. That left toxic insecticides and malaria nets as the primary methods for disease prevention in many tropical areas. Insecticide or drug resistance by the parasite, and the fact that some drugs are ineffective on different vectors of the disease has made it even harder to stop the transmission of malaria.

But according to the pharmaceutical company GlaxoSmithKline, that goal may soon be in sight. A vaccine, which has been developed by GSK, the PATH Malaria Vaccine Initiative and 11 research centers in Africa, is now in the phase three stage of clinical trials in sub-Sahara Africa.

The company has managed to develop a vaccine that utilizes two proteins (RTS and S) from the virus and a form of yeast as its carrier. So far, the vaccine has shown positive results among infants in some of Africa’s most malaria-ridden areas. While its effectiveness still stands at less than 50 percent in most age groups, PATH notes that one of its biggest successes has been the destruction or blocking of the parasite in the liver, where malaria’s destructive sequence begins. Scientists have developed a means by which to heighten the body’s defense mechanism against the disease. It’s yet to be seen whether they have also developed a mechanism that can be used in other parasite-related diseases.

The medical incentives for developing a vaccine that can protect vulnerable populations from malaria have always been a major concern. But the impact of the disease can be measured economically as well. According to the Centers for Disease Control and Prevention, $12 billion is spent yearly on illness, treatment and the impact of premature deaths worldwide.

“The cost in lost economic growth is many times more than that,” says the CDC.

GSK is awaiting regulatory approval of the vaccine.

“If the required public health information, including safety and efficacy data from the phase III program, is deemed satisfactory,” says GSK, “the WHO has indicated that a policy recommendation for the RTS,S malaria vaccine candidate is possible as early as 2015, paving the way for decisions by African nations regarding large scale implementation of the vaccine through their national immunisation programs.”

Image of community learning how to use mosquito nets - Sallyforthwith

Mosquito - Kompak