UNICEF warned that the pandemic could spread swiftly when children gathered for shots, many countries suspended their inoculation programs. Even in countries that tried to keep them going, cargo flights with vaccine supplies were halted by the pandemic and health workers diverted to fight it.
Now, diphtheria is appearing in Pakistan, Bangladesh and Nepal.
Cholera is in South Sudan, Cameroon, Mozambique, Yemen and Bangladesh.
A mutated strain of poliovirus has been reported in more than 30 countries.
And measles is flaring around the globe, including in Bangladesh, Brazil, Cambodia, Central African Republic, Iraq, Kazakhstan, Nepal, Nigeria and Uzbekistan.
Of 29 countries that have currently suspended measles campaigns because of the pandemic, 18 are reporting outbreaks. An additional 13 countries are considering postponement. According to the Measles and Rubella Initiative, 178 million people are at risk of missing measles shots in 2020.
The risk now is “an epidemic in a few months’ time that will kill more children than Covid,” said Chibuzo Okonta, the president of Doctors Without Borders in West and Central Africa.
As the pandemic lingers, the W.H.O. and other international public health groups are now urging countries to carefully resume vaccination while contending with the coronavirus.
“Immunization is one of the most powerful and fundamental disease prevention tools in the history of public health,” said Dr. Tedros Adhanom Ghebreyesus, director general of the W.H.O., in a statement. “Disruption to immunization programs from the Covid-19 pandemic threatens to unwind decades of progress against vaccine-preventable diseases like measles.”
But the obstacles to restarting are considerable. Vaccine supplies are still hard to come by. Health care workers are increasingly working full time on Covid-19, the infection caused by the coronavirus. And a new wave of vaccine hesitancy is keeping parents from clinics.
Many countries have yet to be hit with the full force of the pandemic itself, which will further weaken their capabilities to handle outbreaks of other diseases.
“We will have countries trying to recover from Covid and then facing measles. It would stretch their health systems further and have serious economic and humanitarian consequences,” said Dr. Robin Nandy, chief of immunization for UNICEF, which supplies vaccines to 100 countries, reaching 45 percent of children under 5.
The breakdown of vaccine delivery also has stark implications for protecting against the coronavirus itself.
At a global summit earlier this month, Gavi, the Vaccine Alliance, a health partnership founded by the Bill and Melinda Gates Foundation, announced it had received pledges of $8.8 billion for basic vaccines to children in poor and middle-income countries, and was beginning a drive to deliver Covid-19 vaccines, once they’re available.
But as services collapse under the pandemic, “they are the same ones that will be needed to send out a Covid vaccine,” warned Dr. Katherine O’Brien, the W.H.O.’s director of immunization, vaccines and biologicals, during a recent webinar on immunization challenges.
Battling Measles in Congo
Three health care workers with coolers full of vaccines and a support team of town criers and note-takers recently stepped into a motorized wooden canoe to set off down the wide Tshopo River in the Democratic Republic of Congo.
Although measles was breaking out in all of the country’s 26 provinces, the pandemic had shut down many inoculation programs weeks earlier.
The crew in the canoe needed to strike a balance between preventing the transmission of a new virus that is just starting to hit Africa hard and stopping an old, known killer. But when the long, narrow canoe pulled in at riverside communities, the crew’s biggest challenge turned out not to be the mechanics of vaccinating children while observing the pandemic’s new safety strictures. Instead, the crew found themselves working hard just to persuade villagers to allow their children to be immunized at all.
Many parents were convinced that the team was lying about the vaccine — that it was not for measles but, secretly, an experimental coronavirus vaccine, for which they would be unwitting guinea pigs.
In April, French-speaking Africa had been outraged by a French television interview in which two researchers said coronavirus vaccines should be tested in Africa — a remark that reignited memories of a long history of such abuses. And in Congo, the virologist in charge of the coronavirus response said that the country had indeed agreed to take part in clinical vaccine trials this summer. Later, he clarified that any vaccine would not be tested in Congo until it had been tested elsewhere. But pernicious rumors had already spread.
The team cajoled parents as best they could. Although vaccinators throughout Tshopo ultimately immunized 16,000 children, 2,000 others eluded them.
This had been the year that Congo, the second-largest country in Africa, was to launch a national immunization program. The urgency could not have been greater. The measles epidemic in the country, which started in 2018, has run on and on: Since this January alone, there have been more than 60,000 cases and 800 deaths. Now, Ebola has again flared, in addition to tuberculosis and cholera, which regularly strike the country.
Vaccines exist for all these diseases, although they are not always available. In late 2018, the country began an immunization initiative in nine provinces. It was a feat of coordination and initiative, and in 2019, the first full year, the percentage of fully immunized children jumped from 42 to 62 percent in Kinshasa, the capital.
This spring, as the program was being readied for its nationwide rollout, the coronavirus struck. Mass vaccination campaigns, which often mean summoning hundreds of children to sit close together in schoolyards and markets, seemed guaranteed to spread coronavirus. Even routine immunization, which typically occurs in clinics, became untenable in many areas.
The country’s health authorities decided to allow vaccinations to continue in areas with measles but no coronavirus cases. But the pandemic froze international flights that would bring medical supplies, and several provinces began running out of vaccines for polio, measles and tuberculosis.
When immunization supplies finally arrived in Kinshasa, they could not be moved around the country. Domestic flights had been suspended. Ground transport was not viable because of shoddy roads. Eventually, a United Nations peacekeeping mission ferried supplies on its planes.
Still, health workers, who had no masks, gloves or sanitizing gel, worried about getting infected; many stopped working. Others were diverted to be trained for Covid.
The cumulative impact has been particularly dire for polio eradication — around 85,000 Congolese children have not received that vaccine.
But the disease that public health officials are most concerned about erupting is measles.
More contagious than Covid
Measles virus spreads easily by aerosol — tiny particles or droplets suspended in the air — and is far more contagious than the coronavirus, according to experts at the Centers for Disease Control and Prevention.
“If people walk into a room where a person with measles had been two hours ago and no one has been immunized, 100 percent of those people will get infected,” said Dr. Yvonne Maldonado, a pediatric infectious disease expert at Stanford University.
In poorer countries, the measles mortality rate for children under 5 ranges between 3 and 6 percent; conditions like malnutrition or an overcrowded refugee camp can increase the fatality rate. Children may succumb to complications such as pneumonia, encephalitis and severe diarrhea.
In 2018, the most recent year for which data worldwide has been compiled, there were nearly 10 million estimated cases of measles and 142,300 related deaths. And global immunization programs were more robust then.
Before the coronavirus pandemic in Ethiopia, 91 percent of children in the capital, Addis Ababa, received their first measles vaccination during routine visits, while 29 percent in rural regions got them. (To prevent an outbreak of a highly infectious disease like measles, the optimum coverage is 95 percent or higher, with two doses of vaccine.) When the pandemic struck, the country suspended its April measles campaign. But the government continues to report many new cases.
“Outbreak pathogens don’t recognize borders,” said Dr. O’Brien of the W.H.O. “Especially measles: Measles anywhere is measles everywhere.”
Wealthier countries’ immunization rates have also been plunging during the pandemic. Some American states report drops as steep as 70 percent below the same period a year earlier, for measles and other diseases.
Once people start traveling again, the risk of infection will surge. “It keeps me up at night,” said Dr. Stephen L. Cochi, a senior adviser at the global immunization division at the C.D.C. “These vaccine-preventable diseases are just one plane ride away.”
Starting again
After the W.H.O. and its vaccine partners released the results of a survey last month showing that 80 million babies under a year old were at risk of missing routine immunizations, some countries, including Ethiopia, the Central African Republic and Nepal, began trying to restart their programs.
Uganda is now supplying health workers with motorbikes. In Brazil, some pharmacies are offering drive-by immunization services. In the Indian state of Bihar, a 50-year-old health care worker learned to ride a bicycle in three days so she could take vaccines to far-flung families. UNICEF chartered a flight to deliver vaccines to seven African countries.
Dr. Cochi of the C.D.C., which provides technical and program support to more than 40 countries, said that whether such campaigns can be conducted during the pandemic is an open question. “It will be fraught with limitations. We’re talking low-income countries where social distancing is not a reality, not possible,” he said, citing Brazilian favelas and migrant caravans.
He hopes that polio campaigns will resume swiftly, fearing that the pandemic could set back a global, decades-long effort to eradicate the disease.
Dr. Cochi is particularly worried about Pakistan and Afghanistan, where 61 cases of wild poliovirus Type 1 have been reported this year, and about Chad, Ghana, Ethiopia and Pakistan, where cases of Type 2 poliovirus, mutated from the oral vaccine, have appeared.
Thabani Maphosa, a managing director at Gavi, which partners with 73 countries to purchase vaccines, said that at least a half dozen of those countries say they cannot afford their usual share of vaccine costs because of the economic toll of the pandemic.
If the pandemic cleared within three months, Mr. Maphosa said, he believed the international community could catch up with immunizations over the next year and a half.
“But our scenarios are not telling us that will happen,” he added.
Jan Hoffman reported from New York, and Ruth Maclean from Dakar, Senegal.