The effectiveness of Pfizer’s Covid-19 vaccine for children declined rapidly during the outbreak of the Ômicron variant. According to new data from the New York Department of Health, the reduction was especially among children ages 5 to 11, but the immunizer still maintained protection against serious illness.
One month after vaccination with the two doses, Pfizer’s effectiveness against infection caused by the Omicron variant dropped from 68% to just 12% in the youngest children eligible for vaccination, those aged 5 to 11 years.
The effectiveness against hospitalization in this age group was higher, but it also dropped substantially, from 100% in early December to just 48% in late January.
“The data is not surprising as the vaccine was developed in response to an earlier variant of Covid-19 and the reduced efficacy of two doses against the Omicron variant was observed to some extent with all vaccines and ages,” said the Commissioner of New York State Health Mary Bassett in a statement posted online.
“It is critical to emphasize that vaccination is still recommended for everyone aged five and over, including children aged 5 to 11. I encourage parents and guardians to consult their pediatrician about vaccinating their children, and boosting if eligible, as soon as possible.”
Children aged 5 to 11 years receive a dose of Pfizer vaccine that is 10 micrograms, one third of the dose given to children and youth aged 12 to 17 years.
The study also revealed that while the vaccine’s effectiveness also declined for older children and adolescents, the reduction occurred more slowly than for elementary school students. For any outbreak caused by Covid-19, the effectiveness of the vaccine decreased from 66% in early December to 51% in late January for children aged 12 to 17 years. For hospitalizations, vaccine effectiveness dropped from 85% to 73% over the same period.
The data was published on Monday as a preprint study on the medRxiv server. Preprints are articles that have not been peer-reviewed by outside experts or accepted for publication in a medical journal.
The authors concluded that if other studies repeat these findings, the vaccine dose for younger children may need to be revised. The authors also said the data may demonstrate the need to continue “layered protections, including the use of masks, to prevent infection and transmission” in younger children.
The US Centers for Disease Control and Prevention (CDC) is collecting its own data on the vaccine’s effectiveness in children, which should be released soon.
“Pfizer’s and Moderna’s Covid-19 vaccines continue to offer high levels of protection against serious illness, hospitalization and death in all age groups, despite decreasing efficacy against infection alone during the Omicron wave,” the statement said. agency in a statement.
“CDC continues to monitor and evaluate vaccine efficacy data as it becomes available, but these vaccines work well and are the best tool we have to prevent serious outcomes.”
Source: CNN Brasil
