If clinical trials for COVID-19 vaccines aren鈥檛 expanded soon to include children, it鈥檚 unlikely that even kids in their teens will be vaccinated in time for the next school year.
The hurdle is that COVID vaccine makers are only in the early stages of testing their products on children. The Pfizer vaccine authorized for use by the Food and Drug Administration on Friday was greenlighted only for people ages 16 and up. Moderna just started trials for 12- to 17-year-olds for its vaccine, likely to be authorized later this month.
It will take months to approve use of the vaccines for middle- and high school-aged kids, and months more to test them in younger children. But some pediatricians say that concerns about the safety of the front-runner vaccines make the wait worthwhile.
Although most pediatricians believe the eventual vaccination of children will be crucial to subduing the COVID virus, they鈥檙e split on how fast to move toward that, says , professor of pediatrics at the University of Maryland School of Medicine鈥檚 Center for Vaccine Development and Global Health. Campbell and colleagues say it鈥檚 a matter of urgency to get the vaccines tested in kids, while others want to hold off on those trials until millions of adults have been safely vaccinated.
Much of the debate centers on two issues: the degree of harm COVID-19 causes children, and the extent to which children are spreading the virus to their friends, teachers, parents and grandparents.
COVID-19鈥檚 impact on children represents a tiny fraction of the suffering and death experienced by vulnerable adults. Yet it would qualify as a pretty serious childhood disease, having caused 154 deaths and more than 7,500 hospitalizations among people 19 and younger in the United States. Those numbers rank it as worse than a typical year of influenza, and worse than diseases like mumps or hepatitis B in children before the vaccination era.
show that infected with the virus end up requiring intensive care, Dr. Stanley Plotkin, professor emeritus of pediatrics at the University of Pennsylvania, . That鈥檚 in line with the percentage who become gravely ill as result of infections like Haemophilus influenza type B, or Hib, for which doctors have vaccinated children since the 1980s, he pointed out.
Campbell, who with colleagues has developed a plan for how to run pediatric COVID vaccine trials, points out that 鈥渋n a universe where COVID mainly affected children the way it鈥檚 affecting them now, and we had potential vaccines, people would be clamoring for them.鈥
The evidence that teens can transmit the disease is , and transmission has been documented in children as 8. Fear of spread by children has been enough to close schools, and led the American Academy of Pediatrics to that children be quickly included in vaccine testing.
鈥淭he longer we take to start kids in trials, the longer it will take them to get vaccinated and to break the chains of transmission,鈥 said , a professor of pediatrics at Stanford University who chairs the AAP鈥檚 infectious disease committee. 鈥淚f you want kids to go back to school and not have the teachers union terrified, you have to make sure they aren鈥檛 a risk.鈥
Other pediatricians worry that early pediatric trials could backfire. , chief of pediatric infectious diseases at Tufts Medical Center and a member of the FDA鈥檚 advisory committee on vaccines, is worried that whatever causes Multisystem Inflammatory Syndrome in Children, a rare but frightening COVID-related disorder, might also be triggered, however rarely, by vaccination.
Meissner abstained from the committee鈥檚 vote Thursday that supported, by a 17-4 vote, an emergency authorization of the Pfizer vaccine for people 16 and older.
鈥淚 have trouble justifying it for children so unlikely to get the disease,鈥 he said during debate on the measure.
But panel member Dr. Ofer Levy, director of the at Boston Children鈥檚 Hospital, said the 16-and-up authorization would speed the vaccine鈥檚 testing in and approval for younger children. That is vital for the world鈥檚 protection from COVID-19, he said, since in the United States and most places 鈥渕ost vaccines are delivered early in life.鈥
While vaccines given to tens of thousands of people so far appear to be safe, the lack of understanding of the inflammatory syndrome means that children in any trials should be followed closely, said , director of the Division of Microbiology and Infectious Diseases at the National Institute of Allergy and Infectious Diseases.
, vaccine companies are required eventually to test all their products on children. By late last month, Pfizer had vaccinated approximately 100 children 12-15 years of age, said spokesperson Jerica Pitts.
Moderna has started 12 and over in another clinical trial, and other companies have similar plans. Assuming the trials show the vaccines are safe and provide a good immune response, future tests could include progressively younger children, moving to, say, 6- to 12-year-olds next, then 2- to 6-year-olds. Eventually, trials could include younger toddlers and infants.
Similar stepdown approaches were taken to test vaccines against human papillomavirus (HPV), influenza and other diseases in the past, Erbelding noted. Such trials are easiest to conduct when researchers know that a measurable immune response, like antibody levels in the blood, translates to effective protection against disease. Armed with such knowledge, they can see whether children were protected without them having to be exposed to the virus. Federal scientists hope to get that data from the Moderna and Pfizer adult vaccine trials, she said.
Vaccine trials geared to tweens or younger children may involve testing half-doses, which, if protective, would require less vaccine and might cause fewer incidents of sore arms and fevers that afflicted many who鈥檝e received the Pfizer and Moderna vaccines, Campbell said.
But unless additional studies begin quickly, the window for having an FDA-authorized vaccine available before the next school year 鈥,鈥 said Dr. , a pediatrics professor at Emory University. 鈥淥ur younger children are almost certainly going into next school year without a vaccine option available for them.鈥
In the meantime, teachers are likely to be high on the priority list for vaccination. Protecting school staff could allow more schools to reopen even if most children can鈥檛 be vaccinated, Erbelding said.
Eventually, if the SARS-CoV-2 virus remains in circulation, governments may want to mandate childhood vaccination against the virus to protect them as they grow up and protect society as a whole, Plotkin said.
In the 1960s, Plotkin invented the rubella vaccine that has been given to hundreds of millions of children since. Like COVID-19, rubella, or German measles, is not usually a serious illness for children. But congenital rubella syndrome afflicted babies in the womb with blindness, deafness, developmental delays and autism. Immunizing toddlers, which, in turn, protects their pregnant mothers, has indirectly prevented hundreds of thousands of such cases.
鈥淲e don鈥檛 want to use children to protect everyone in the community,鈥 said Campbell. 鈥淏ut when you can protect both children and their community, that鈥檚 important.鈥
And while a coronavirus infection may not be bad for most children, missed school, absent friends and distanced families have caused them immense suffering, he said.
鈥淚t鈥檚 a huge burden on a child to have their entire world flipped around,鈥 Campbell said. 鈥淚f vaccinating could help to flip it back, we should begin testing to see if that鈥檚 possible.鈥
This story was produced by , which publishes , an editorially independent service of the .
