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Can malaria finally be eradicated?

Special for Infobae of New York Times.

(Science Times: Global Health)

Miriam Abdullah spent her entire childhood in and out of hospitals, her thin body wracked with fever and ravaged by malaria. She got so sick and so often that her constant treatments exhausted her parents, who also cared for her numerous siblings, both financially and emotionally.

“There was a time when even my mom gave up,” recalled Abdullah, now 35.

In Nyalenda, the poor community in Kisumu, Kenya, where Abdullah lives, malaria is endemic and ubiquitous. Some of his friends developed meningitis after being infected; one of them passed away. “Malaria has really plagued us as a country,” he said.

There are tens of millions of horror stories like Abdullah’s, handed down from generation to generation. But now, a change is coming: Malaria is one of the few global health scourges that experts are optimistic about, so much so that some have started talking about eradicating the disease.

“I think there is a lot of room for optimism,” said Philip Welkhoff, director of malaria control programs at the Bill & Melinda Gates Foundation. “In a few years, in this very decade, we could really roll out an initiative that brings cases down to zero.”

Last year, China and El Salvador were certified as malaria-free territories, and in the six countries that the Mekong River flows through, including Vietnam and Thailand, cases have been reduced by almost 90 percent. By 2025, around 25 countries are expected to have eliminated malaria.

Currently, most infections occur in Africa. Even on that continent, despite restrictions imposed by the coronavirus pandemic, almost 12 million more African children received medicine to prevent malaria in 2020 than in 2019.

However, the arrival of two new vaccines heralds a much bigger change. The first, called Mosquirix, took 35 years to make. It was approved by the World Health Organization last year and may already be in distribution by the end of next year.

A more powerful malaria vaccine, developed by the Oxford University team that created AstraZeneca’s COVID-19 vaccine, could arrive in a year or two. This formulation, which has shown up to 80 percent efficacy in clinical trials, is believed by many experts to be the one that could transform the fight against malaria.

And there are still more options on the horizon, including an mRNA vaccine being developed by the German company BioNTech; monoclonal antibodies that can prevent malaria for six months or more; bed nets with long-lasting insecticides or chemicals that paralyze mosquitoes; as well as new ways to catch and kill mosquitoes.

“It’s an exciting time,” said Rose Jalang’o, who led a pilot trial of the Mosquirix vaccine in Kenya, where it was given to children along with other immunizations.

However, making the world malaria-free will require more than promising tools. In many African countries, the distribution of vaccines, medicines and bed nets involves overcoming myriad challenges, including rough terrain, other pressing medical priorities and misinformation.

Although funding for malaria control programs is much more generous than for many other diseases that plague poor nations, resources remain limited. Pouring money into one initiative often causes funders to overlook others, fueling competition and sometimes rancor.

The Mosquirix vaccine cost more than $200 million to develop over more than 30 years, but it is about half as effective as the Oxford vaccine, called R21. The first doses of Mosquirix will not reach African children until late 2023 or early 2024. Supply will be severely constrained for a number of reasons, and is expected to remain so for years.

R21, the second vaccine, appears to be more powerful, cheaper and easier to produce. And the Serum Institute of India is poised to manufacture more than 200 million doses of R21 a year.

Some malaria experts say that, given the urgent need, the world needs all available options. But others worry that all the dollars going to Mosquirix now are dollars that will not be used to develop other tools.

“Financing is already scarce for existing malaria control measures,” said Javier Guzmán, director of global health policy at the Center for Global Development in Washington. “I don’t want to be negative, but a new tool without additional funds, in essence, implies a sacrifice, an opportunity cost.”

‘Move too fast’

Malaria is one of the oldest and deadliest infectious diseases. Years of major progress stalled a decade or so ago. In 2019, it left a balance of 229 million new infections and 558,000 deaths.

Although the COVID pandemic did not cause malaria infections to skyrocket, as tuberculosis did, the pandemic reversed a slow downward trend in malaria deaths, which rose to 627,000 in 2020.

Nearly all of the lives lost to malaria resided in sub-Saharan Africa, where about 80 percent of deaths are children under 5 years of age.

Many of the strategies to combat malaria are outdated, but remain inaccessible to millions. For example, only about half of African children sleep in beds covered with insecticide-impregnated mosquito nets, and even fewer receive seasonal drugs that prevent infection.

Malaria aggravates social inequalities. It robs children of the ability to fight off other pathogens, overwhelms health care systems, and destroys entire communities. An untreated person with malaria can remain ill for six months, giving mosquitoes the opportunity to spread the parasite to up to 100 other people.

The parasite wrecks the body so quickly that by the time children are admitted to hospital, many urgently need a blood transfusion. But blood supplies are often in short supply in sub-Saharan Africa, and using a bag of blood for a young child can mean half or more is wasted, explained Mary Hamel, who directs the malaria vaccine implementation program at the WHO.

“You see a child who is pale and weak and breathing rapidly, and he is lying there on the table, and there is nothing you can do,” he described.

“Malaria has to be prevent; it’s moving too fast,” she added.

Mosquirix, the first vaccine against any parasite, is a technical milestone. But its efficacy, at 40 percent, is much lower than scientists expected.

Ideally, the vaccine should be distributed alongside existing control measures, such as insecticide-impregnated bed nets and preventative medications, based on data indicating where the tools are most needed, and delivered by a strong team of workers Of the health.

“If combined with the right tool, you can have a much bigger impact,” said Thomas Breuer, director of global health at GlaxoSmithKline, which makes the Mosquirix vaccine.

However, in many African countries, mistrust of vaccines is high. In a survey, about half of people in Niger and the Democratic Republic of the Congo said they would not trust a malaria vaccine.

In addition, Mosquirix should be given in four doses, the first at 5 months of age and the fourth at 18 months of age. But children older than 18 months rarely receive further vaccinations, and many African parents face huge logistical hurdles in getting their children to a clinic.

Limited resources

Compared to the billions of dollars spent on COVID vaccines, the funding for malaria is a pittance. The Gates Foundation spends some $270 million a year fighting the disease, not counting its contributions to the Global Fund to Fight AIDS, Tuberculosis and Malaria.

Scarce resources mean that people—and organizations—end up choosing their favorite strategies. Some argue that controlling the mosquito population is the most logical route, while others promote vaccination, with some saying that monoclonal antibodies are the way forward.

In such a competitive context, Mosquirix is ​​not positioned as the clear winner.

“Deploying a tool that is expensive, not as effective, and short-lived may not be the best strategy to get started,” said Scott Filler, director of malaria control programs for the Global Fund, which supports more half of the malaria control programs in the world.

Perhaps the money would be better spent on increasing the use of bed nets, or ensuring that people have access to basic primary health care services, such as malaria testing, treatment and monitoring, Filler suggested.

However, other experts believe that, given the devastation wrought by malaria, a low-efficacy vaccine is better than none.

“We have this vaccine that has been tested really extensively, more than any other vaccine before it was approved,” said Michael Anderson, who was director general of the UK Department for International Development and now heads MedAccess, a nonprofit organization. profit financed by the British government.

The development of the R21 vaccine has cost less than 100 million dollars. If regulators move with the same speed they showed on COVID-19 vaccines, it could be licensed a few months after researchers deliver final data later this year.

Many parents in Africa are looking forward to a vaccine. In Kisumu, Abdullah is eager to vaccinate her 2-year-old daughter, who has already had malaria once, to protect her from the disease that marred her own childhood.

“I would go for her immediately,” he assured. “In fact, I would go for it before I go for the COVID-19 vaccine.”

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