Six months ago we told you about the possibility of a vaccine against malaria, which is now awaiting regulatory approval. Last week news emerged of another breakthrough discovery which could help prevent people dying from one of the world’s most dangerous diseases.
According to a research article in the journal Science, a team of scientists based in the United States has identified a group of Tanzanian children who have naturally-occurring resistance to malaria. Normally hard for the human body to combat, malaria parasites enter into the human blood stream by way of a mosquito bite and then invade red blood cells where they multiply, before bursting out in great number, overwhelming the human immune system and heading for new cells. Their success consists of spending much of their time inside human cells, so the immune system cannot identify them except for brief moments.
The children identified in Tanzania produced antibodies which stopped malaria parasites leaving infected red blood cells, thereby limiting their opportunity to continue reproducing before the infected cells are destroyed naturally in the spleen. The research was confirmed by checking against a survey of 138 Kenyan men and adolescent boys with the antibodies who were found to have a significantly lower number of parasites than those without.
One of the lead researchers explained that “Most vaccine candidates for malaria have worked by trying to prevent parasites from entering red blood cells. We’ve taken a different approach. We’ve found a way to block it from leaving the cell once it has entered. It can’t go anywhere. It can’t do any further damage.
We’re sort of trapping the parasite in the burning house.
The research was tested on laboratory mice which were given a transfusion of blood containing the antibodies, and then infected with malaria. The result was to cut by nearly 75% the number of malaria parasites infecting the mice, and to double their survival rate. If these results are reproduced in the next stage of the trials – using monkeys – it is hoped that a vaccine will be ready for trials on humans within 18 months.
If successful, this research could go a long way towards reducing the 600,000 deaths from malaria each year. But, as we said in our previous blog which also covered preventive measures, the best way to avoid dying of malaria is to avoid being bitten by a mosquito!