Two mRNA Vaccines Are Not the Same

In the early days of the COVID-19 mRNA vaccine rollout in the USA this year, vaccines were in short supply and people had no choice as to which vaccine to try.  Both two-dose vaccines from Pfizer and Moderna seems to have similar 95% efficacy against serious disease.  Recent studies are revealing significant differences between the Pfizer and Moderna vaccines. 

Moderna has nearly 3X the amount of active ingredients in Pfizer: 100mg vs 30mg.  Moderna created 2.6X more antibodies in patients than Pfizer – with both being negatively correlated with patient age and both declining exponentially over time.  The higher amount of initial antibodies allow Moderna to be more effective and durable against the Delta variant than Pfizer: the risk of a breakthrough case was 2X lower.  While Pfizer is recommending a booster 6 months after the second shot, Moderna is recommending a booster before this winter.  Moderna’s proposed booster has only 50 mg of active ingredients, but it is still proving to be highly effective in phase 2 clinical trials to date.   

As for side effects, a greater percentage of participants who received the Moderna vaccine reported reactogenicity: 82% vs 69% for Pfizer.  Many people (13%) taking Pfizer reported side effects with both doses that sidelined them for 1-2 days.  A small percentage (0.6%) reported symptoms severe enough to require a visit to the ER, and only 0.25% required hospitalization.  It is believed that serious side effects with Moderna are also <1%. 

If you are immunocompromised and probably did not get full protection from two shots – get your booster shot now unless you had severe side effects.  If you’ve had severe side effects after the second Moderna wait a few weeks for the 50 mg Moderna booster.  Otherwise, on September 20th, all Americans should be eligible for a booster shot.  Get it to improve your protection against severe COVID-19 illness.  Always mask up and social distance for additional layers of protection.     

Comments

Post a Comment

Popular posts from this blog

Could Florida be the Next Epicenter in the COVID-19 Pandemic?

Image
Florida Governor DeSantis has failed to recognize the seriousness of the exploding Covid-19 Pandemic in Florida.   His slow response and poor judgment have already cost many Floridians their lives and may cost many thousands more if he fails to act now.   State Infections/M Infections Deaths Mortality Mortality Coincident Lagged5 NY            2,361 45934 604 1.3% 3.6% NJ               994 8825 108 1.2% 5.1% LA               591 2746 119 4.3% 12.7% WA               486 3700 175 4.7% 8.8% MA               466 3240 35 1.1% 5.1% MI               366 3657 92 2.5% 8.4% CT               362 1291 27 2.1% 8.2% CO                  301 1734 31 1.8% 5.3% IL       
Read more

NYC is now Worse than China 2 days after Wuhan Quarantine

Image
China announced plans to quarantine Wuhan on January 22 when the number of confirmed COVID-19 cases was near 500 and threatened to go exponential or out of control.   The number of confirmed cases in NY state has now passed that threshold by 3 days and it is growing exponentially. Most of the confirmed cases in NY, NJ, and CT are located in the metro-NYC area.   If the US wants to adopt China’s successful, albeit painful, quarantine program they must do so NOW.   Many people with the benefit of hindsight criticized China for such draconic measures while others criticized them for doing it too late.   WHO seemed to be the only major organization that had praised China for its decisive action at that time.   Now is the time for Governor Cuomo, or really President Trump to adopt a strategy similar to China’s before the virus escapes the hot zones such as metro-NYC, Seattle, and San Franciso and the pandemic gets out of con
Read more

Pre-Thanksgiving Dip in COVID-19 Cases

Image
COVID-19 cases in the USA have shown a sharp decrease over the last 8 days causing the 7-day rolling average to peak and rollover (see figure below – red squares).   The question is whether this is measuring a real lasting phenomenon – perhaps attributable to local COVID-19 fires burning out, or to mitigation factors taking hold, or to some temporary factor associated with the Thanksgiving holiday.   The answer is probably a combination of all three that will ultimately be overwhelmed by an increase in Thanksgiving transmission. Some COVID-19 outbreaks have burned so strongly and for so long (3-4 months) that local “herd immunity” may be acting as a retardant to the fire.   For example, in North Dakota (ND) 10.3% of the population has now been confirmed infected (see table below).   State Confirmed Testing Est. Pop Deaths Death per Fatality   Infection % Positive % Infection %
Read more