By
Chioma Umeha
In recent years, the world has recorded tremendous
progress in the fight against malaria. The World Malaria Report 2015 shows
malaria mortality rates have fallen by 66 per cent among all age groups and by
71 per cent among children under five in Africa since 2000.
But, there is still work to do just as a new
vaccine developed by a US-based team is showing promising results, and could
accelerate progress.
Creating the vaccine, researchers infected people
with weakened, genetically modified forms of the Plasmodium falciparum parasite
in safety trials.
The weakened malaria parasite, while unable to
complete its lifecycle and develop into full-blown malaria, exposes the immune
system to the disease and stimulates a response that could block an actual
infection.
After tests on ten people during trials, the
results were encouraging: there were no cases of full malaria infection and no
significant side-effects.
Describing the positive test results as “critical
milestones for malaria vaccine development,” Sebastian Mikolajczak, one of the
project researchers, the modified parasite used in tests is both safe and
immunogenic.
“The clinical study now shows that the vaccine is
completely attenuated in humans and also shows that even after only a single
administration, it elicits a robust immune response against the malaria
parasite,” says Mikolajczak, according to an online report.
Published findings of test trials say while
“creating genetically defined and weakened parasite strains that are safe for
vaccination remains challenging,” the recorded results “warrant further
clinical testing.”
The prospect of an effective malaria vaccine is
great news for Africa, where the disease remains rampant: 90 per cent of
malaria deaths in 2015 occurred in Africa.
There is also significant effort on the continent
to develop vaccines as well. Last August, scientists at the University of Cape
Town’s Drug Discovery and Development Centre (H3D) announced the discovery of a
new anti-malaria compound which could “contribute to the eradication of
malaria.”
Professor Kelly Chibale, founder and director of
H3D, says the compound “has potent activity against all stages of the malaria
parasite life-cycle and has the potential to block transmission of the parasite
from person to person.”
One step closer to malaria vaccine
The results of this research are all the more
hopeful, as there are roughly 5,000 malaria genes, and through the erasure of
three of them, formidable results were attained. “Immunization of humans with
whole sporozoites gives complete, sterilizing resistance against malaria
infection. However, achieving dependable safety while maintaining
immunogenicity of whole parasite vaccines remains a difficult challenge,” the
study indicates.
Malaria, An ongoing threat
A completely practicable vaccine is, however, far
from being settled. While there are a high number of trials under tests, the
virus still affects approximately 200 million people by the year, as research
points out. The disease seems because of plasmodium, a microscopic parasite
that blights the human body through the means of mosquito bites, which allow a
form of the parasite to get under the human skin.
Once inside the human body the virus occurs in the
liver, where its sporozoites infected the organ with 30,000 copies of the pest.
From the liver, the virus gets into the blood stream, where it attacks red
blood cells, which from time to time results into the patient’s death.
Because the contamination follows these three
stages, it is more difficult to create a fully functional vaccine to prevent it
from spreading all over the body and, finally, affecting the blood cells.