Breakthrough malaria vaccine offers to reinvigorate the fight against the disease
The World Health Organization has announced a historic move: it has recommended the widespread use of the first ever malaria vaccine. The recommendation is based on the results of an ongoing pilot programme in Malawi, Ghana and Kenya. Malaria is a huge global health challenge, around 409,000 people died of malaria in 2019 alone. The WHO African region carries significant proportion of the malaria burden – 94% of all malaria cases and deaths occurred in the region. Children younger than five are the most vulnerable. Ina Skosana asked Eunice Anyango Owino to explain the development, and its significance.
It has taken 30 years. Why so long?
The most significant reason is that the malaria parasite is very complex. It has different stages; some in the mosquito and some in the human. Thus, scientists had to pursue a diversity of approaches.
For example, in the human there are two stages. These are the:
- Pre-erythrocytic stages (sporozoite, or spore-like, stage). This is the period when the parasite’s sporozoite from a mosquito bite enters the blood stream and heads for the liver to mature and multiply after which they are then released.
- The blood stage (Merozoite stage). This is when the parasite’s merozoites are released from the liver, and multiply in the red blood cells.
So an effective vaccine against the first stage (pre-erythroctic stage) would be one that elicits an immune response that would either prevent infection of the liver cells or lead to destruction of the infected liver cells.