Myocarditis collab with my friend Dr. Elisabeth Marnik. We have summarized all the info that is available thus far on the risk of myocarditis and pericarditis with the mRNA vaccines per CDC ACIP’s briefing this week. This far, the CDC maintains that the benefits outweigh the risks. We will continue to update as more information
Dr David Fisman, an epidemiologist at the Dalla Lana School of Public Health and a friend of mine, recently made these graphs on herd immunity. The vaccine uptake we need to see to achieve herd immunity is based on vaccine efficacy & reproduction number of the dominant variant in circulation. With Delta, numbers needed to
1/ Protection after two doses The most important decision is to get second dose: stronger + longer lasting protection. Two doses of AZ effective at preventing serious illness from OG Covid-19 + early variants. Early studies show good immune response when Moderna/Pfizer used as second dose. 2/ Protection against new variants Delta variant spreading quickly.
Here’s a visual on the new real-world study assessing effectiveness of AstraZeneca and Pfizer vaccines against the Alpha and Delta variants. This study underscores the importance of being fully vaccinated with two doses, given the rising number of Delta variant cases in Ontario and
I am often asked what the impact of vaccination in pregnancy or lactation would be specific to passive transfer of antibodies and immunity. Here I try and outline the different types of antibodies, their function and what the subsequent impact would be on the fetus or
What exactly is vaccine efficacy? Efficacy is a measure of how well a vaccine works in clinical trials – specifically, the percent reduction of disease by comparing two groups – one that receives the vaccine and one that doesn’t, under favourable and tightly controlled settings. However, how one measures efficacy can vary significantly. Within the
Small increased risk of rare types of blood clots accompanied with thrombocytopenia (low platelets). Called ‘vaccine-induced prothrombotic immune thrombocytopenia’ or VIPIT. VIPIT is very rare. Initial estimates from Germany were 4 per million. Subsequent Norwegian estimates are 42 per million. Per Science Table estimates: occurring in anywhere from 1 in every 125,000 to 1 in