By Manas Mishra

(Reuters) – In June, U.S. Food and Drug Administration advisors will meet to determine whether they recommend authorizing. Moderna (NASDAQ) Inc’s vaccine to children younger than 6 years. Pfizer Inc (NASDAQ:), and BioNTech Se (NASDAQ:),’s COVID-19 vaccine is for children under 5 years of age.

This is an overview of some factors that will be taken into consideration in the decision regarding the age group not covered by the previous U.S. regulations for COVID-19 vaccinations.

How many do you need?

Moderna filed a FDA authorization request for Spikevax’s two-dose vaccine regimen. It is intended to be used in children aged 6-6 years. Although Pfizer is yet to file its FDA authorization, its clinical trial showed that a three-dose vaccine was safe for children aged 6 months to 5 years.

Moderna plans to use a 25 micrograms dose in that age group, lower than the 100 micrograms used in the first two doses in adults and the 50 micrograms used as a booster dose for non-immunocompromised adults. Moderna gave the doses at 28-day intervals during its clinical trial.

Pfizer and BioNTech tested a 3-microgram Comirnaty vaccine in children younger than 5 years. The 10 microgram version was used by children 5-11 years, while the 30 microgram dose was used for adults 12-12 years. The first and second doses were administered to children approximately three weeks apart. After that, the third dose was given at least three months later.

Side effects of vaccines can be reduced by using lower dose versions.

HOW EFFECTIVE are VACCINES

The Moderna vaccine was tested in clinical trials that involved approximately 6,700 children. Its effectiveness in the prevention of symptomatic infection in children 6 months through 2 years old was 43.7%. Children 2-6 years old were only 37.5%.

To determine the final efficacy number, there haven’t been sufficient COVID-19-symptomatic cases among children in the Pfizer BioNTech trial. A preliminary analysis of 10 COVID-19 patients with symptoms that were symptomatic in the Omicron coronavirus version was sufficient to determine an efficacy rate of 80.3% for the children below 5. Pfizer will be updating those numbers after 21 patients in the trial are diagnosed with COVID-19.

ARE VACCINES SAFE TO CHILDREN?

Pfizer trial data which included 1678 children showed side effects that were comparable to those seen in adults. Pfizer claimed that the low-dose, 3-microgram vaccine was chosen because it had a better safety profile. Although it didn’t disclose any safety data on the vaccine, Pfizer said that it was as safe as the placebo in this study.

Moderna found that most side effects had mild or moderate severity, and the fever was similar to what children experienced with vaccines. Children aged between 2 and 6 years old, as well as those 2 months-to-2 years old, experienced fevers of more than 104 degrees Fahrenheit.

Moderna claimed that no cases of myocarditis nor pericarditis were reported during the trial. Pericarditis is a type of inflammation in the heart and has been shown to be linked with vaccines against mRNA in very rare instances in young men.

Based on data from Pfizer, the U.S. Centers for Diseases Control and Prevention stated that heart disease rates in young boys aged 5-11 years have been lower than those in teens and young adults.

WHY VACCINATE YOUR CHILDREN EARLY?

Parents will need to make the decision whether or not to have their children immunized if these shots are approved by regulators in this age group. They might be unsure if it’s worth the effort, given how many children became infected by Omicron. Experts believe that natural immunity diminishes with time. The data shows that COVID-19 protection is less effective in adults than in children, as well as in older people, who are infected and have received booster shots. Dr. Matthew Harris, Northwell Health’s pediatric emergency medicine doctor, said that this has been proven to be true in both adult and child patients.

Harris said that vaccinations protect against deaths and hospitalizations. Harris believes these are important reasons to recommend that parents vaccinate their children.

FDA set June 15, 2015 as the deadline for reviewing the Moderna/BioNTech vaccinations.