Should parents delay their child's second dose of the coronavirus vaccine?

More than two years into the pandemic, the United States and Canada became the first countries to approve a two-dose mRNA vaccine for children as young as 6 month.

Previous research has found that waiting longer than the usually recommended three to four weeks between the first two injections may boost immunity and reduce the risk of side effect.

It's time to build defenses

Earlier this year, New York City-based Pfizer and Mainz, Germany-based BioNTech reported in a preliminary trial that a two-dose mRNA vaccine was less than 50% effective against symptomatic disease in children 6 months to 4 years old .

The mRNA vaccine made by Cambridge, Massachusetts-based Moderna requires only two doses, administered every four week.

These interval recommendations date back to initial adult clinical trials in 2020. In the face of a global pandemic that killed about 3,000 people a day in the .

From an immunological standpoint, it makes sense to wait a little longer than the three- to four-week window, because it takes time for the immune system to build up its defense.

national experiment

Here's what's happening in Canada in March 2021. Vaccines are scarce, so the country has opted to delay a second dose of adults to allow more people to receive at least one dos.

Some studies have also shown that longer vaccination intervals can extend beyond the laboratory, prevent hospitalizations, and provide modestly enhanced protection against infection in one preprin.

Despite mounting evidence of the need for longer intervals between vaccines, many scientists are concerned because the studies were mostly conducted in adults and adolescents, rather than young children whose immune systems have not yet fully develope.

government advice

The Centers for Disease Control and Prevention (CDC) recommends that children 6 months to 4 years wait 3 to 8 weeks between their first two doses of the Pfizer vaccine, and children 6 months to 5 years old Wait 4 to 8 weeks between second doses of the Moderna vaccin.

The Centers for Disease Control and Prevention website states that, based on studies of adults and adolescents, gaps of up to 8 weeks in people ages 6 months to 64 years may help boost antibody levels and reduce two very rare side effects Small chance of: myocarditis and pericarditis, which involve inflammation of the hear.

So while the government's advice is overly cautious, many scientists believe it may be exaggerated -- at least as far as these rare side effects are concerne.

Finally, in theory, the benefits of parents waiting longer for a second dose of their child's vaccine do not outweigh the risk of contracting Covid-19 while waitin.

But in our country, in the long run, it is better to wait 8 week.