(Reuters) – The vaccination of about 88% of Americans who received the first dose of Pfizer / BioNTech or COVID-19 vaccines from Moderna was completed, according to a study of more than 12 million people by the US Centers for Disease Control and Prevention (CDC) shown.
Both vaccines, among the first to receive U.S. permission for emergency use, require two shots. The high efficacy of the vaccines is based on trials with intervals of 21 days for Pfizer Inc / BioNTech SE and 28 days for and Moderna Inc’s vaccine.
According to the analysis, about 3% of people in the United States who received the first dose of one of the vaccinations did not receive the second dose to complete vaccination, the agency said Monday.
The agency said 8.6% did not receive the second dose but were still within the allowable interval to receive it.
The analysis was done in 58 jurisdictions in the United States among people who received their first shot between December 14 and February 14. The data was published Monday in the Weekly Report of Morbidity and Mortality.
A second analysis of 14.2 million people who received the second dose showed that 95.6% received the dose on time, the agency said.
The CDC considered a second shot in time, or within the recommended interval, if given within 17-25 days after the first dose for Pfizer-BioNTech, and 24-32 days for Moderna vaccine.
Other countries, such as the United Kingdom, have extended the period between doses to months instead of weeks to vaccinate more people as they have supply shortages. U.S. public health officials have said they do not intend to make any changes to their recommendations.
(Reported by Manojna Maddipatla in Bengaluru; edited by Caroline Humer and Shinjini Ganguli)