Angelique Coetzee was puzzled. The South African doctor had been seeing COVID-19 patients who mostly had sore throats and fevers. But on November 18 Coetzee examined a 29-year-old man complaining of extreme fatigue and severe headaches—symptoms more in line with heat stroke than COVID-19. By the end of the day, Coetzee had treated seven or eight similar cases.
“It didn’t make any sense to me,” says Coetzee, chair of the South African Medical Association.
Within a week, researchers determined that the patients were infected with a new SARS-CoV-2 variant, now known as Omicron, that has a large number of mutations and can spread more rapidly than previous variants. Omicron is now dominant in South Africa and many other countries, including the United States.
Omicron’s rise has reignited discussion about how to ensure the entire world can get a jab. The World Health Organization has set a target of vaccinating 70 percent of the global population by mid-2022. But while wealthy countries like the U.S. have already immunized more than 60 percent of their populations, vaccination in low-income countries is lagging. In South Africa only 27 percent of the population is fully vaccinated, while in Nigeria, Papua New Guinea, and Sudan that number is less than 3 percent.
The problem goes beyond supply constraints. Experts say low-income countries face massive infrastructure challenges to distribute doses quickly and widely. They argue that wealthy countries have more than just a moral obligation to help address vaccine equity, because when the virus is circulating anywhere, it has more opportunities to mutate and spread.
Mutations are normal for a virus, whose only purpose is to infect cells and replicate inside of them. In a single person’s body, the SARS-CoV-2 virus might copy its own genome at least thousands of times. Coronaviruses have so-called proofreading enzymes to keep them from introducing mistakes into their genetic code, but errors are bound to slip through, and that’s when mutations occur.
Most of these mutations are useless or even destructive to the virus, points out Wendy Barclay, a virologist at Imperial College London. She says the chance that a mutation will give an advantage to the virus, such as making it more transmissible or able to evade immunity from vaccination, is as low as 1-in-100,000. But those odds increase the more a virus is allowed to replicate.
The best way to keep new variants from arising is thus to deny the virus the opportunity to spread and replicate. That can be done by social distancing, wearing masks, and testing—but the best weapon is widespread vaccination.
“As long as Africa is not vaccinated, you will never be able to sleep soundly,” Coetzee says.
How vaccination suppresses variants
Vaccines have two main advantages: They save lives by preventing people from getting severely sick, and they help control viral replication. Breakthrough infections in vaccinated people tend to be mild, which means a sick person won’t exhale as much virus for as long as they would if they were unvaccinated. That gives the virus less time to replicate inside the body and fewer opportunities to multiply in the rest of the population.
That’s where vaccine equity comes in. Allowing a virus as transmissible as SARS-CoV-2 to run through parts of the world where large swaths of people are unvaccinated creates a real problem, says Ingrid Katz, associate faculty director at the Harvard Global Health Institute. “The only way to get in front of it is to use everything in your arsenal, and that includes vaccinating the world,” she says.
Although it’s nearly impossible to pinpoint the exact origins of a viral variant, we do know that in India, low levels of vaccination played a role in the catastrophic emergence and surge of the Delta variant earlier this year.
In early 2021 the country had begun rolling out vaccines only to those at high risk of severe disease due to their age, comorbidities, or frequent exposure to the virus. The rest of the adult population wasn’t scheduled for shots until September 2021.
“All this was based on premise that India was out of the danger zone,” says K. Srinath Reddy, president of the Public Health Foundation of India. Cases and deaths were low in mid-January, and experts were predicting that India had built up enough herd immunity to avoid another wave. Then, Reddy says, India saw a surge of travel, election rallies, and religious festivals.
“It was as though India had turned its back on the virus, though the virus had not turned its back on us,” he says.
The Delta variant was first identified in March, when less than one percent of the population of nearly 1.4 billion people was fully vaccinated. Sure enough, cases and hospitalizations surged—soon followed by a staggering loss of life. (How India’s second wave became the worst COVID-19 surge in the world.)
A shaky start to vaccine supplies
Unfortunately, vaccine inequities began to build long before any COVID-19 vaccines were even approved. Wealthy countries pre-ordered hundreds of billions of doses in early deals with pharmaceutical companies—leaving low-income countries without access to the vaccines from the start.
“You set up a system of inequity right from the get-go,” Katz says.
The WHO partnered with international nonprofits to address those inequities through COVAX, an initiative to secure doses for low-income countries. But vaccines are still disproportionately going to wealthy countries as they administer booster doses.
Some countries have stepped up their donations in the name of vaccine equity, but Reddy points out that these donations have not always been well thought out. In the last year, there have been several high-profile instances in which wealthy countries waited to share their vaccine stockpiles until they were close to expiring—causing hundreds of thousands of donated doses to go to waste. For instance, South Sudan had to destroy nearly 60,000 doses in April, and up to a million doses went to waste in Nigeria in November.
“That’s not charity—that’s just dumping,” Reddy says.
Still, Amavi argues that COVAX has made an extraordinary difference in addressing vaccine equity for COVID-19 compared to past vaccination campaigns. The human papillomavirus vaccine, for example, first became available in 2006—but many African countries have only had access to it in the last couple of years.
“With COVAX we have seen that in less than one year, all COVID-19 vaccines have been made available everywhere,” Amavi says. “I think it is a great achievement to have bridged the gap between producing countries and African countries that were not receiving the vaccine in the beginning.”
The rocky road to global distribution
Once countries have secured enough doses, though, they must figure out how to distribute them. And although low-income countries might get discounts on the jabs, it costs them more than high-income countries to roll out the shots.
“It’s a challenge in Africa,” Coetzee says. “It doesn’t matter how many donations you give us.”
According to the Global Dashboard for Vaccine Equity, low-income countries would have to increase their healthcare spending by an average of nearly 57 percent to vaccinate 70 percent of their populations. That’s because many low-income countries lack the infrastructure—from electrical grid capacity to a trained healthcare workforce—to rapidly administer doses to billions of people. Distributing the mRNA vaccines is particularly daunting since they require access to cooler trucks and ultra-cold storage at healthcare facilities that are under-resourced even in the best of times.
By contrast, high-income countries only need to increase spending by less than an additional one percent to vaccinate their entire populations.
In India, the arrival of the Delta variant prompted the country to step up immunizations. Reddy says that the country has used drones to help get doses into remote areas and has launched a door-to-door vaccination campaign. India’s health minister reports that 85 percent of its eligible population has now had a first doseand more than half is fully vaccinated. However, many low-income countries simply lack the capacity to mobilize thousands of healthcare workers to go door-to-door—if they have that many trained professionals at all.
Yet another challenge is convincing people to take the vaccine. Amavi says much of the vaccine hesitancy across the world can be blamed on a COVID-19 infodemic—or the spread of misinformation and disinformation that has been sowed by the anti-vax movement.
But Katz says people in low-income countries are also understandably skeptical. She points to early reports that the Pfizer and Moderna vaccines were safer and more efficacious than those available to low-income countries, such as AstraZeneca and Johnson & Johnson.
Although this imbalance was because of cold-chain issues, Katz says it created some understandable vaccine hesitancy in countries where people feel they have gotten stuck with the worse vaccines. To remedy this, she says, public health experts must do better to reassure the population that the vaccines they’re receiving are safe and effective.
What can be done about inequities?
Solutions to vaccine inequities start at the country level. Katz says that wealthy countries can share more of their stockpiled vaccine doses or even forgo their place in line for upcoming shipments. The international community can also provide financial assistance for low-income countries to build up healthcare infrastructure—which would also help during the inevitable next pandemic.
Public health experts have also called on Moderna and Pfizer to help low-income countries produce their own mRNA vaccines—which would dramatically reduce the burdens of acquiring, transporting, and distributing them. Katz says this would require the companies not just to release their intellectual property rights but also to share their technology and raw materials.
She adds that although the Pfizer and Moderna vaccines stood out early on—proving to be more than 90 percent effective at preventing severe disease—there is promising new evidence for other vaccines.
The one-dose Johnson & Johnson vaccine, for example, was only 66.3 percent effective in its original clinical trials, but the company reported in the fall that a second dose raised the vaccine’s efficacy against moderate to severe disease caused by the original virus to 94 percent. Although the J&J shot may be less effective against newer variants, Katz argues that this data shows two doses of the jab are about as effective as the mRNA vaccines.
Barclay, too, points to new data out of the United Kingdom showing that mixing vaccines can boost immunity. A study published in The Lancet found that people who initially received two doses of the AstraZeneca vaccine had higher levels of immunity after receiving a booster of one of the six other vaccines that are available.
“So all is not lost,” she says. If countries can make progress getting the first shots in arms, they can always come back and boost with the mRNA vaccines.
Coetzee, meanwhile, advocates for developing vaccine tablets that can be administered more easily in low-income countries. Even if the mRNA vaccines could be made widely available in low-income countries, they would still need cooler trucks to transport it and enough trained medical personnel to mix the vaccine, dilute it, portion it out into a syringe, and administer doses.
“Everything can potentially lead to an error,” she says. “To give a tablet, there’s not a lot that can go wrong. You just need to make sure that the patient swallows the tablet.”
Ultimately, most experts agree that policymakers and voters everywhere need to understand that their safety is ephemeral until more of the world is vaccinated. Katz urges people to make donations, advocate within their communities, and petition their governments to do more to address vaccine equity.
“When will we learn that we have to be in collaboration globally?” she says. “We cannot go on like this.”
Coetzee agrees. She suggests that richer countries launch programs to allow their citizens to sponsor vaccines for people in low-income countries. Beyond that, she says, everyone who has access to shots can help simply by getting vaccinated, getting boosted if you’re eligible, masking up, and practicing social distancing and hand washing.
“What are you doing as a responsible citizen?” she asks. “You also need to play a role.”
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