Name: Why Mosquitos Are Humanity’s Deadliest Creature
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Malaria overwhelms the body before it has a chance to fight back, making the development of a vaccine especially challenging.

About 80% of deaths caused by Malaria annually are young children, below the age of five.

Why Mosquitos Are Humanity’s Deadliest Creature

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Malaria overwhelms the body before it has a chance to fight back, making the development of a vaccine especially challenging.

About 80% of deaths caused by Malaria annually are young children, below the age of five.

Nature

Timothy C. Winegard:Wolves and sharks kill about 10 people per year, whereas the mosquito, this tiny little animal the size and weight of a grape seed, is responsible for up to a million deaths a year.But it's not the mosquito itself, it's the pathogens that hitch a free ride that caused so much suffering, death and destruction. And of all the pathogens that mosquitoes carry, by far the most lethal and the biggest killer of humanity has been malaria.Ally Olotu:As night falls, this is the most vulnerable time. That's when the mosquitoes come in. When the mosquito bites, it inject into that child small parasites. We call them sporozoites. These spend a very few minutes in the blood and then quickly go and start to multiply within the liver.And these kids could be playing around, they can be playing football, they could be singing with their parents. Nobody can suspect anything. But from the liver, within a few days, you could have thousands and thousands of parasite release into the blood.They attack our red blood cells, and destroying them, and this is what actually give rise to malaria symptoms. That child you saw playing with his friends just few days ago can quickly become severely sick. And if not diagnosed and treated very fast, that child might lose life.Speaker 3:It's this process, the way the body is overwhelmed before it has a chance to fight back, that makes malaria so dangerous and the development of a vaccine so challenging.Ally Olotu:We have developed vaccines for other diseases of course, but most of these are viruses and bacteria, which are much simpler pathogens compared to malaria. It's a very complex parasite.Katie Ewer:When an infected female mosquito takes a bite and injects sporozoites, malaria parasites, there's about a half-hour to two-hour window before the parasites invade the cells in your body and set up infection there, and that's the window that we're trying to target with our vaccine.Speaker 3:What the R21 vaccine must do is mobilize an army of antibodies.Adrian Hill:The problem has been to produce enough antibodies to clear all of those parasites very quickly.When people are infected with malaria, they make antibodies in the blood that stick to the outside of the parasite. They're meant to stop it in its tracks before they can reach the liver, but in a natural infection, there just aren't enough antibodies.Speaker 3:Threatened by just a few invading parasites, our antibody response is usually too little, too late. But luckily, the malaria sporozoite has an Achilles heel. To invade the liver, it relies on a coating called CSP, the circumsporozoite protein.Adrian Hill:What we need are large amounts of very specific antibodies that bind as tightly as possible to the circumsporozoite protein. Then we should be able to stop the parasites.

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Why Mosquitos Are Humanity’s Deadliest Creature

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Nigeria’s Bet on Beating Drug-Resistant Malaria

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