At a time when much of the world is still struggling to get access to COVID vaccines, whether or not to vaccinate children can feel like a privilege. On July 19, UK vaccination advisors recommended that vaccination be postponed for most young people under the age of 16 because the rate of serious illness in this age group was very low. But several countries, including the United States and Israel, have made headway, and others hope to follow suit if supplies allow.
nature investigates where the evidence is about children and COVID vaccines.
It is necessary?
Since the beginning of the pandemic, parents have been comforted by the fact that SARS-CoV-2 causes serious illnesses far less often in children than in adults.
But some children still get very sick, and the specter of prolonged COVID – a constellation of sometimes debilitating symptoms that can last months even after a mild attack of COVID-19 – is enough for many pediatricians to target one as soon as possible Urge vaccination. “I spent the pandemic caring for children in a children’s hospital,” says Adam Ratner, a pediatric infectious disease specialist at New York University. “We didn’t see as many as on the adult side, but we did see a lot of children who were pretty sick.”
However, vaccination counselors in the UK have recommended that, for the time being, only vaccinate adolescents who are clinically at risk or who are living with vulnerable adults. Serious illness, death, and even prolonged COVID are rare in healthy teens and children, and almost all adults at risk will soon have received two doses of the vaccine, Bristol University pediatrician Adam Finn told reporters at a media briefing.
However, in some countries little is known about how COVID affects children. For example, some official numbers on hospital admissions and deaths from COVID in sub-Saharan Africa do not break down cases by age. As a result, pediatricians do not know what deaths have occurred in children and adolescents and how conditions such as malnutrition or concomitant tuberculosis or HIV infection could affect outcomes from COVID. “We’re in the dark,” says Nadia Sam-Agudu, a pediatrician at the University of Maryland School of Medicine in Baltimore who works in Nigeria.
Additionally, some pediatricians are concerned about what will happen to children who are co-infected with SARS-CoV-2 and other common viruses such as respiratory syncytial virus, which is one of the causes of colds but can sometimes cause more severe respiratory illness in toddlers. Tight lockdowns have kept this problem at bay in some regions, but as social distancing measures are relaxed, there are already signs that respiratory syncytial virus infections in children are on the rise, says Danilo Buonsenso, a pediatrician at Gemelli University Hospital in Rome. “We don’t yet know what the burden of co-infection in children will be when we have massive circulation of routine viruses and COVID,” he says.
Is it safe to vaccinate children?
A handful of vaccines were tested in young people over the age of 12, including mRNA vaccines from Moderna and Pfizer-BioNTech, and two Chinese vaccines from Sinovac and Sinopharm. And several countries, including the United States, Israel, and China, are now offering vaccines to this age group. Other studies are expected to soon provide results in young people over the age of 12, including studies on the Zydus Cadila vaccine and the inactivated coronavirus vaccine Covaxin, both of which are made in India.
So far, the vaccines appear to be safe in adolescents and some companies have started clinical trials in children as young as 6 months. In the United States, vaccines for those under the age of 12 could be available later this year, says pediatrician Andrea Shane of Emory University in Atlanta, Georgia.
A possible link between the Pfizer vaccine and inflammation of the heart – conditions known as myocarditis and pericarditis – has emerged since Israel and the United States began vaccinating young people. However, the researchers have yet to determine that the vaccine caused the inflammation. Most people have recovered, and the data suggests the risk of these conditions is “extremely low,” says pediatrician David Pace of the University of Malta in Msida – on the order of about 67 cases per million second doses in male adolescents aged 12-17 and 9 per million in adolescent women of the same age group.
How will vaccinating children and adolescents affect the pandemic?
Malta has fully vaccinated 80% of its population – one of the highest vaccination rates in the world – and is now vaccinating adolescents aged 12 and over. The decision there to vaccinate young people was shaped, among other things, by the tight family structures in a country where young people often have frequent contact with their grandparents, says Pace. “At the population level, vaccinated youth can lead to a reduction in transmission to vulnerable older people,” he says. Young people in Malta also often travel abroad to school and may import coronavirus infections and variants from abroad, he adds.
Data shows that children, and especially adolescents, can play a significant role in the transmission of the coronavirus, says Catherine Bennett, an epidemiologist at Deakin University in Melbourne, Australia. And concern about child and teen transmission is growing as new variants of coronavirus emerge. It’s possible that more transmissible variants could develop a way of enforcing a young person’s immune response that makes them more resistant to infection, says Bennett. All the more important that he is vaccinated.
Hopes of herd immunity through vaccination have faded, so countries must do their best to keep transmission low, she adds: “It only takes a poorly vaccinated population to create global variants.”
Is vaccinating children fair?
Chile, another country with one of the highest COVID vaccination rates in the world, is also introducing vaccines for people 12 and older.
But Miguel O’Ryan, a former member of two government advisory committees who pushed for aggressive vaccination campaigns, now wonders if it is time to slow down. “The countries with pediatric vaccination probably shouldn’t be moving this fast,” said O’Ryan, a pediatric infectious disease specialist at the University of Chile in Santiago. “Other countries, even our neighbors, are struggling to get enough vaccines for their high-risk groups.”
O’Ryan isn’t the only one worried about using valuable vaccines to vaccinate children while more vulnerable populations around the world are still struggling to keep their supplies safe. In May, World Health Organization chief Tedros Adhanom Ghebreyesus said wealthier countries that vaccinate children are doing so at the expense of health workers and high-risk groups in other countries. However, proponents of vaccinating children and young adults argue that neither one nor the other need to be the case. “It’s kind of a false dichotomy,” says Ratner. Sam-Agudu agrees, pointing out that some wealthy countries have bought more than enough doses to fully vaccinate their populations. “The argument for shipping vaccines abroad shouldn’t rule out vaccinating children in higher-income countries,” she says.
And more steps could be taken to improve the supply of vaccines to countries in need, Bennett says. More could be done to better target donations, she notes. For example, instead of allocating donated vaccine doses to countries based solely on the number of people living there, they could be allocated based on other factors, such as: E.g. the need to maintain health care in the face of an impending malaria season or ongoing measles outbreak. “We still probably didn’t have the deep epidemiological war space we need to identify the problem and the best way to address it,” she says. “There are a number of ways to look at this.”
This article is reproduced with permission and was first published on July 20, 2021.