Alida writes:

I really enjoy listening to the weekly update on “This week in virology” but I was very curious when I heard you say it is a must to aspirate before injecting an IM.

In Canada, we have not done this practice for more than 20 years. I started nursing school in 2000 and I have never aspirated and I have given thousands of vaccines and injections.

The CDC does not recommend aspiration before injection.,painful%20for%20infants%20(20).

Just my thoughts!

Alida Fernhout, RN, MPH

Deepa writes:

Dear Dr. Griffin: I have been advised by my most excellent rheumatologist to skip 2 doses of Methotrexate after taking any vaccine (including the one for SAR-CoV-2) based on the attached publication.

This is the first study that I am aware of, that carefully evaluated the immune response to the flu vaccine in RA patients. They randomized to 2 cohorts – one that skipped 2 doses of Methotrexate and one that did not. There is a quite a remarkable and significant difference in the antibody response elicited – in favor of skipping Methotrexate. The key finding  – MTX discontinuation for 2 weeks after vaccination significantly increases the immunogenicity of a seasonal influenza vaccine in patients with RA, who had been on a stable dose of MTX, without significantly increasing risk of disease activity.

I hope this is helpful to you, your patients and listeners to this podcast. Not many people are aware of this study. We need more studies like this.

As a Ph.D. immunologist and a biotech investor and entrepreneur, I really appreciate your science first approach. Thank you also to the awesome Twiv team, particularly Dr. Vincent Racaniello.



He sent: Impact of temporary methotrexate discontinuation for 2 weeks on immunogenicity of seasonal influenza vaccination in patients with rheumatoid arthritis: a randomised clinical trial 

MaryAnn writes:

Hi Dr. Griffin,

I received my 1st dose of the Pfizer vaccine on March 23rd. At the time that I signed up for that vaccine, Walgreens had us schedule the second dose 4 weeks out, and my next dose is scheduled for April 20th, which is 28 days from the first dose.

I found out yesterday, via the NYTimes ( that Walgreens had taken it upon themselves to schedule these second doses at their “convenience” rather than at the tested interval, which should be 3 weeks/21 days. It never even occurred to me that it would be wrong.

Walgreens is being difficult to deal with, and will not allow the second dose to be rescheduled until 20 days after the first dose…the day before dose 2 is actually due. They are now telling customers that the CDC said that 28 days was just fine, and they approved it. Of course, according to reporting, the CDC says no such thing, though they do say that the vaccine should be ok any time in the 3-6 week window, even though that is not the researched interval, if it can’t be scheduled on time. Walgreens certainly isn’t taking any accountability for this screw up. It shouldn’t have been up to them to make this scheduling decision. I’m angry, and I’ll never spend another dime in their chain ever.

I am trying to get my second dose through another source, to bring it closer to the 3 week time frame, but so far no luck. With the phases opening to more people, there are even fewer vaccine slots available, local health departments have either Moderna or J&J (so that doesn’t help), and I suspect that I will simply need to keep the appointment for the 2nd dose at the 28 day mark. Now, of course, I lack some confidence in this, and I suffer from extreme “white coat” anxiety, so this makes it even worse.

So, any advice? Should I be looking at a booster sooner rather than later? Should I be asking my doctor for antibody testing? What can I do to feel better about this situation? I was looking forward to getting out of my house again. Now I feel unsure again. I figure I’ll be wearing a mask forever. 

In a time when my anxiety has been over the moon, thank you (and the whole TWiV team) for being a calm place to find accurate information. You guys get an A++. Walgreens gets an F-. 


Williamsburg, VA

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