WHO Approved a Malaria Vaccine for Children – a Global Health Expert Explains Why That Is a Big Deal

Jerri-Lynn here. Although it’s way above my pay grade to comment on the scientific significance of this breakthrough, I note that malaria remains a huge global problem  and not just in Africa, nor only for the rural poor. I know of people who’ve contracted the disease  in the heart of urban India: Bombay, Calcutta.

By Miriam K. Laufer, Professor of Pediatrics, Medicine, Epidemiology and Public Health at the Center for Vaccine Development and Global Health, University of Maryland School of Medicine Originally published at The Conversation.

The World Health Organization recommended its first malaria vaccine for children on Oct. 6, 2021 – a breakthrough hailed by the U.N. agency as a “historic moment.”

Approval of the RTS,S/AS01 vaccine, which goes by the name Mosquirix, provides a “glimmer of hope” for Africa, according to Dr. Matshidiso Moeti, WHO regional director for Africa. It will now be rolled out to protect children against one of the world’s oldest and most deadly diseases.

Malaria and global child health expert Dr. Miriam K. Laufer answered The Conversation’s questions about the vaccine and the WHO announcement.

What Has the WHO Announced?

The WHO has recommended the use of the RTS,S malaria vaccine, which is produced by GlaxoSmithKline. It is the first malaria vaccine to be recommended by the global health body.

It follows a review of two years of piloting studies of the vaccine in three sub-Saharan African countries with a high burden of malaria: Malawi, Kenya and Ghana.

After careful evaluation and extensive discussion, the WHO came to the consensus that the vaccine should be recommended for use in children living in areas of moderate to high malaria burden.

Why Is This Seen as a Major Development?

Malaria kills hundred of thousands of children, mostly in sub-Saharan Africa, every year. This is the first time that researchers, vaccine manufacturers, policymakers and advocates have successfully delivered a vaccine that has made it through clinical trials and received not only regulatory approval but also a recommendation from the WHO.

This vaccine prevents about 30% of severe malaria cases that are more likely to lead to death.

Although researchers knew that RTS,S was effective in well-controlled clinical trials, a few questions remained about whether it was feasible for sub-Saharan African countries to safely roll out the four-dose vaccine in a real-world setting. But since 2019, the malaria vaccine implementation program in Malawi, Kenya and Ghana has shown excellent vaccine uptake and a good safety profile. To date, the vaccine has been administered to around 800,000 children in those three countries.

How big a killer is malaria?

Malaria, a parasitic disease transmitted by bites from infected mosquitoes, causes nearly half a million deaths per year, mostly in children in sub-Saharan Africa.

It is a disease that preys on the poorest of the poor. It causes the most disease and death in places where people lack access to basic health care, where housing conditions allow mosquitoes to enter and where inadequate water management provides breeding ground for mosquitoes. Despite international efforts to control it, the burden of malaria has continued and even increased over the past several years.

How Effective Will the Vaccine Be Compared to Other Treatments?

We learned through the report of the trials to the WHO that the vaccine will be able to reach all children in areas of moderate to high risk of malaria. This will save lives from the deadly infection, especially among children with limited access to health services.

Prevention is almost always more cost-effective than treating disease, especially with an infection as common as malaria. Drugs are sometimes used to prevent malaria, but they have to be given frequently, which is both expensive and inconvenient.

In addition, the more often a drug is used, the more likely the malaria parasites will develop resistance to the drug.

Why Did It Take So Long to Develop a Vaccine?

Lack of political will to develop a malaria vaccine certainly played a role in why it took so long. With no real market for a malaria vaccine in resource-rich countries like the U.S., pharmaceutical companies did not have a strong financial incentive to accelerate vaccine development.

But the malaria parasite is also very complex, and the targets of the immune system are diverse, so developing an effective vaccine wasn’t easy.

A vaccine developed against one malaria strain grown in the laboratory generally does not work against many of the malaria parasites that children encounter when bitten by infected mosquitoes, which is why even though RTS,S is a good vaccine, it protects against only 30% of infections.

If you think about this in terms of the COVID-19 vaccine, researchers developed a vaccine against the strain of the disease that was circulating in early 2020. But now we see that the vaccine does not protect people quite as well against the new delta variant. Someday a variant may emerge that completely escapes the vaccine immune response.

For malaria, there are many variants of many different proteins, so finding a vaccine that covers all of these was a huge challenge.

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8 comments

  1. Brooklin Bridge

    I’m curious as to what the average cost of a full treatment would be. I didn’t see it in the article (did I miss it?) and didn’t find anything specifically on this vaccine from a very superficial internet search.

    Reply
    1. Brooklin Bridge

      I did find this, https://pubmed.ncbi.nlm.nih.gov/33428635/

      Results: At a vaccine price of $5 per dose and assuming the vaccine is donor-funded, our estimated incremental financial costs range from $1.70 (Kenya) to $2.44 (Malawi) per dose, $0.23 (Malawi) to $0.71 (Kenya) per dose delivered (excluding procurement add-on costs), and $11.50 (Ghana) to $13.69 (Malawi) per FVC. Estimates of economic costs per dose are between three and five times higher than financial costs. Variations in activities used for costing, procurement add-on costs, unit costs of per diems, and allowances contributed to differences in cost estimates across countries.

      Reply
  2. Larry Y

    I looked up the funding and research effort; it was a long time coming.

    Via
    https://theconversation.com/worlds-first-mass-malaria-vaccine-rollout-could-prevent-thousands-of-children-dying-169457

    – Government did the heavy lifting with 30 years of research via a partnership between GlaxoSmithKline (GSK) and the Walter Reed Army Institute of Research. Long term basic R&D was involved, as “the antigen design and the adjuvant system were novel”

    – Bill and Melinda Gates Foundation is also involved. Between them and GSK, the quoted cost is $700 million. I’m glad someone did it, but it’s an indictment of our system that it was left to them.

    Reply
  3. William Hunter Duncan

    “In addition, the more often a drug is used, the more likely the malaria parasites will develop resistance to the drug.”

    Wouldn’t that also be true for the vaccine, since it is a mRNA vaccince and those who take it can still carry malaria?

    Reply
    1. Michaelmas

      William Hunter Duncan: it is a mRNA vaccince and those who take it can still carry malaria/

      It’s NOT an mRNA vaccine, for god’s sake. Nowhere does the article say it is.

      It’s an old-school recombinant vaccine — your granddad’s genetic engineering, basically — made from a modified hepatitis B virus core protein and epitopes of the Plasmodium falciparum circumsporozoite protein. The latter is what travels from a mosquito’s gut to a human liver, and causes malaria. So this vaccine shows those epitopes to a human immune system and thereby creates malarial resistance to some greater or lesser degree.

      Whether it creates sterilizing immunity, I don’t know.

      Most vaccines don’t create sterilizing immunity, FYI. Granted, most vaccines aren’t as leaky as the mRNA vaccines seem to be with COVID19 Delta. But Delta creates remarkably high viral loads and is remarkably infectious.

      Reply
  4. AJB

    I notice the WHO’s decision to recommend the malaria vaccine was off the back of a two year pilot trial that included 650,000 children.

    It is interesting that the COVID vaccines are being recommended for use in children off only 6-months of trial data in 2000 or so participants.

    Malaria kills thousands of children each year, whereas COVID kills almost none.

    Does the testing/trial logic seem 180 degrees out of balance – the vaccine for the disease that kills kids by the thousands is tested in children for 2-years, while the vaccine for the disease that barely kills any children is only tested for in children for 6-months.

    Is that because first world children are a more lucrative market so time to market is the pharma company’s primary objective?

    Reply
    1. Larry Y

      It’s because of the children (and adults) not affected by malaria. Malaria is currently endemic in SE Asia, Sub-saharan Africa and parts of Latin America. No Big Pharma there, while Russia’s climate precludes mosquito transmission, and China got to zero-malaria on it’s own.

      A less cynical answer is that a longer period is necessary to check out effectiveness (as opposed to proving safety) against a more complicated carrier (various protozoa vs. corona virus).

      Unlike with COVID-19, zero malaria is a proven and well known strategy. It has been implemented, over the last hundred years, multiple times throughout the world. Non-pharmaceutical interventions are effective, and there’s multiple prophylaxis treatment. Heck, there’s even a program with genetically engineering mosquitos (with no

      Reply
  5. Patrick Donnelly

    Very few viruses kill their host. Obviously.
    The body’s reaction can kill the host.
    Ivermectin etc all dampen the immune reaction. They save lives, but cost so little, there is no profit for the Company.

    Reply

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