Pfizer and BioNTech’s two-dose Covid vaccine provided very little protection for children aged 5 to 11 during the wave of omicron infection in New York, according to a study published Monday.
The New York State Department of Health found that the effectiveness of Pfizer’s vaccine against Covid infection plummeted from 68% to 12% for kids in that age group during the omicron surge from Dec. 13 through Jan 24. Protection against hospitalization dropped from 100% to 48% during the same period.
The study has not yet undergone peer review, the academic gold standard. Due to the public health urgency of the pandemic, scientists have been publishing the results of their studies before such review.
The team of public health officials who conducted the study said the dramatic drop in vaccine effectiveness among children 5 to 11 years old was likely due to the lower dosage they received. Kids in this age group are given two 10-microgram shots, while children aged 12 to 17 receive 30-microgram shots.
The researchers also compared 11 and 12 year olds during the weekend ended Jan. 30. They found the vaccine effectiveness plunged to 11% for the low-dosage group but offered 67% protection to the group that received the higher dose.
“Given rapid loss of protection against infections, these results highlight the continued importance of layered protections, including mask wearing, for children to prevent infection and transmission,” the public health officials wrote in the study.