5 Scandinavian countries limit or halt Moderna
Five Scandinavian countries limit or halt Moderna
[Media report.] Finland has joined Sweden, Denmark and Norway in either banning or discouraging young adults or teens from getting the Moderna COVID-19 vaccine, because of the increased risk of myocarditis — heart inflammation. And on Friday, Iceland halted distribution of Moderna in general. "The Chief Epidemiologist has decided that the Moderna vaccine against Covid-19 will not be used in Iceland while further information is obtained on the safety of the vaccine during booster vaccinations," says a statement from Iceland health officials.
Moderna’s data not strong enough to support booster shots, FDA says
[Media report.] Scientists at the U.S. Food and Drug Administration said on Tuesday that Moderna Inc. had not met all of the agency’s criteria to support use of booster doses of its COVID-19 vaccine, possibly because the efficacy of the shot’s first two doses has remained strong. FDA staff said in documents that data for Moderna’s vaccine showed that a booster does increase protective antibodies, but the difference in antibody levels before and after the shot was not wide enough, particularly in those whose levels had remained high. [See also FDA briefing document.]
WHO advisers recommend 3rd COVID vaccine dose for highest-risk groups
[Media report.] The Strategic Advisory Group of Experts (SAGE) said people who are moderately or severely immunocompromised should be offered an additional dose in the vaccine series, since they are less likely to respond adequately to vaccination with the standard series and are at high risk for severe disease. WHO leaders have previously urged countries to postpone broader use of booster doses to free up more vaccine for countries that had much less access to supplies. SAGE said its third-dose recommendation applies to all vaccines that the WHO has approved for emergency use. They include Pfizer-BioNTech, AstraZeneca-Oxford, Johnson & Johnson, Moderna, Sinopharm, and Sinovac. [See also SAGE document.]
Waning of BNT162b2 Vaccine Protection against SARS-CoV-2 Infection in Qatar
[Pfizer.] We used a matched test-negative, case–control study design to estimate vaccine effectiveness. Estimated BNT162b2 effectiveness against any SARS-CoV-2 infection was negligible in the first 2 weeks after the first dose. It increased to 36.8% (95% confidence interval [CI], 33.2 to 40.2) in the third week after the first dose and reached its peak at 77.5% (95% CI, 76.4 to 78.6) in the first month after the second dose. Effectiveness declined gradually thereafter, with the decline accelerating after the fourth month to reach approximately 20% in months 5 through 7 after the second dose. Effectiveness against symptomatic infection was higher than effectiveness against asymptomatic infection but waned similarly. Variant-specific effectiveness waned in the same pattern. Effectiveness against any severe, critical, or fatal case of Covid-19 increased rapidly to 66.1% (95% CI, 56.8 to 73.5) by the third week after the first dose and reached 96% or higher in the first 2 months after the second dose; effectiveness persisted at approximately this level for 6 months. BNT162b2-induced protection against SARS-COV-2 infection appeared to wane rapidly following its peak after the second dose, but protection against hospitalization and death persisted at a robust level for 6 months after the second dose.
Waning Immune Humoral Response to BNT162b2 Covid-19 Vaccine over 6 Months
[Pfizer.] We conducted a 6-month longitudinal prospective study involving vaccinated health care workers. The study included 4868 participants, with 3808 being included in the linear mixed-model analyses. The level of IgG antibodies decreased at a consistent rate, whereas the neutralizing antibody level decreased rapidly for the first 3 months with a relatively slow decrease thereafter. Six months after receipt of the second dose, neutralizing antibody titers were substantially lower among men than among women (ratio of means, 0.64; 95% confidence interval [CI], 0.55 to 0.75), lower among persons 65 years of age or older than among those 18 to less than 45 years of age (ratio of means, 0.58; 95% CI, 0.48 to 0.70), and lower among participants with immunosuppression than among those without immunosuppression (ratio of means, 0.30; 95% CI, 0.20 to 0.46). Six months after receipt of the second dose of the BNT162b2 vaccine, humoral response was substantially decreased, especially among men, among persons 65 years of age or older, and among persons with immunosuppression.