The Centers for Disease Control and Prevention’s independent vaccine experts recommended a Pfizer Covid booster shot for children ages 5 to 11 on Thursday, as infections rise across the country and immunity from the first two doses wanes off.
The committee voted 11-1 in favor of a booster for the age group. CDC Director Rochelle Walensky will likely sign off on the panel’s recommendation, which would allow pharmacies, doctors’ offices and other health-care providers to start administering the shots.
Covid infections are rising again in the U.S as more transmissible omicron subvariants sweep the country. The U.S. is reporting more than 99,000 new infections a day on average as of Tuesday, a 22% increase over the week prior, according to CDC data. Hospitalizations have also increased 22% over the past week, with more than 3,000 people admitted with Covid a day on average, according to the data.
Though Covid is generally less severe in children than adults, more kids ages 5 to 11 have been hospitalized during the omicron wave than at any other point during the pandemic, according to CDC data. Public health officials are also concerned about children developing long-term health conditions such as long Covid and multisystem inflammatory syndrome, MIS-C for short, a serious condition associated with Covid infection that impacts multiple organ systems.
More than 8,000 children have developed MIS-C since the start the pandemic, with kids ages 5 to 11 most commonly affected at 46% of reported cases, according to CDC data. Sixteen children in the age group have died from MIS-C, 23% of the 68 total reported fatalities across kids of all ages.
Currently, only 29% of children ages 5 to 11 in the U.S. have received their first two Pfizer doses, according to the CDC. Since the pandemic began, more than 4.8 million kids in the age group have caught Covid and more than 15,000 have been hospitalized, according CDC data.
As cases increase, the immune protection provide by the vaccines against infection has waned off as more time has elapsed since people got their primary vaccination series. Omicron and its subvariants are also adept at evading the antibodies that block infection.
In the 5 to 11 age group, Covid vaccination was 43% effective against infection 59 days after the second dose during the period when omicron became the dominant Covid variant, according to CDC data. However, vaccination was 74% effective at preventing hospitalization in 5 to 11-year-olds from April 2021 through January 2022, which includes the periods of delta and omicron dominance.
Pfizer presented data from a small group of 30 children ages 5 to 11 showing that a third dose boosted infection-blocking antibody levels against omicron 22 fold one month after administration compared to two doses. Dr. Charu Sabharwal, Pfizer’s director of vaccine clinical research, said the increased antibody levels should confer real-world protection against the omicron variant, though the company did not present efficacy data during Thursday’s meeting.
Sabharwal said most reactions to the third dose among a broader group of 401 kids were mild to moderate, with fatigue and headache the most common. The rate of fevers was low with none of the kids reporting a temperature great than 104 degrees Fahrenheit, or 40 degrees Celsius. There were no cases of myocarditis or pericarditis, or inflammation of the heart. Ten kids had swollen lymph nodes, but the cases were mild and resolved within a week after onset, according to Pfizer’s data.
More than 18 million Pfizer doses have been administered to 5 to 11-year-olds in the U.S. since the two-dose vaccination series was authorized for the age group in November. The overwhelming majority of reactions to the vaccine, 97%, were not serious, according to CDC data. The most common side effects from the shots were fever, vomiting, headache, dizziness and fatigue.
Myocarditis, an inflammation of the heart, following the second Pfizer shot is rare in boys ages 5 to 11 with 2.7 cases reported per million doses administered, which is far lower than boys ages 12 to 15 who reported 48 myocarditis cases per million doses, according to data from the CDC’s Vaccine Adverse Event Reporting System.
The CDC has verified 20 cases of myocarditis, an inflammation of the heart, in kids ages 5 to 11 as of April following Pfizer vaccination. The overwhelming majority of the myocarditis patients were boys, 17 were hospitalized and 1 died. The boy who died had no evidence of viral infection, developed a fever 12 days after dose 1 followed by stomach pain, vomiting and death on day 13.
The CDC, in a large study published in April, found that the risk of myocarditis is higher after Covid infection than vaccination with Pfizer and Moderna’s shots.