COVID-19 Vaccine Effectiveness Drops Near Zero Within Months: Study | Epoch Times - Naveen Athrappully:
May 6, 2023 - "The effectiveness of COVID-19 vaccines fell below 20 percent a few months after vaccination, with booster shots seeing effectiveness drop below 30 percent.... [A] review, published in the JAMA Network journal on May 3, analyzed 40 studies estimating vaccine effectiveness (VE) over time against laboratory-confirmed COVID-19 infection and symptomatic disease. The studies were selected from 799 original articles, 149 reviews published in peer-reviewed journals, and 35 preprints.
"The review found that the vaccine effectiveness of a primary vaccination cycle against the Omicron infection and symptomatic disease was lower than 20 percent at 6 months from the administration of the last dose. Booster doses restored vaccine effectiveness to levels similar to those seen after administration of the primacy cycle dose. However, nine months after the booster dose, vaccine effectiveness against Omicron was found to be lower than 30 percent against infection and symptomatic disease.
"'The half-life of VE against symptomatic infection was estimated to be 87 days for Omicron compared with 316 days for Delta. Similar waning rates of VE were found for different age segments of the population. These findings suggest that the effectiveness of COVID-19 vaccines against laboratory-confirmed Omicron or Delta infection and symptomatic disease rapidly wanes over time after the primary vaccination cycle and booster dose,' the study said....
"Vaccine effectiveness against Omicron infection was 44.4 percent a month after the completion of the primary vaccination cycle. This fell to 20.7 percent at six months and then to 13.4 percent at nine months. Vaccine effectiveness was found to be higher against the Delta variant as compared to the Omicron variant.... Effectiveness against symptomatic disease fell from 52.8 percent a month after completion of the primary vaccination cycle to 14.3 percent at six months and 8.9 percent at nine months.
“'Our estimates suggest that the initial VE could be different depending on the vaccine product, with higher VE found at one month from the second dose administration for Moderna and Pfizer-BioNTech compared with AstraZeneca and Sinovac.'
"With regard to age, vaccine effectiveness was found to be similar in younger and older age groups against the Omicron variant infection.... 'A significantly lower VE was found for both age groups for Omicron compared with Delta,' it stated."
Read study: https://pubmed.ncbi.nlm.nih.gov/37133863/
doi: 10.1001/jamanetworkopen.2023.10650.
COVID-19 booster effectiveness wanes over time: Study | Good Morning America, February 15, 2022:
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