Marsha writes:

Hi Dr. Daniel,

I live in Toronto, Canada. In October 2022 I tested positive for Covid in a Covid outpatient clinic at Michael Garron hospital.  The doctor on call did not recommend anti virals because I am on Eliquis for Atrial Fib.  I was 68 years old.  I recovered and as far as I know I don’t have long Covid although with aging it’s sometimes hard to know what’s what and our health system in Ontario isn’t what it used to be.

I’m wondering if you can tell me what your recommendation is around blood thinners and anti virals.  I’m concerned in case I get Covid again.  I’m up to 4 Covid vaccines.    I get sick for a week every time I get a Covid shot and so I space them out a bit.

I love this show and particularly your updates.  I find it difficult to find “the real dope” on matters of science and it is a comfort to me to hear you all speak of the research.

Yours truly, 


Bill writes:

Dear Dr. Griffin,

Thank you to you and the TWIV team for all you do for science communication. In response to a question from Portia in TWIV 1036 regarding Paxlovid for her two-year-old grandson, you accurately noted that we need to learn more about using this drug in certain populations. To put a finer point on your response, nirmatrelvir-ritonavir is only authorized for use in people over age 12 years and over 40 kg. The “EPIC-Peds” trial for high-risk children that do not meet these criteria is ongoing ( As you’ve noted before, trials in children are in several ways more challenging than those in adults, not only because of the often smaller numbers of eligible participants but also because new formulations may need to be studied, since younger children cannot typically swallow pills. It may not be as simple as “dissolving” a pill in water; ritonavir is actually an example – when we need to use it in children, it is often an alcohol-based formulation which is not palatable and can be very difficult to convince a child to take.

You’ve done this before on your podcast, but I’m hoping you can remind your listeners who may have children that fulfill the enrollment criteria listed at the site to consider whether they would try to enroll their child in this study, should they live near one of the participating centers and have their high-risk child get infected.

Thanks for all you do,


Bill Muller, MD, PhD

Professor, Pediatrics, Northwestern University Feinberg School of Medicine

Attending Physician, Pediatric Infectious Diseases, Ann & Robert H. Lurie Children’s Hospital of Chicago

Scientific Director, Clinical and Community Trials, Stanley Manne Children’s Research Institute

Danielle writes:

Over 65 here —  with the new BA.2.86 variant around am I better off getting the old booster with the ancestral strain included or waiting for the new XBB derived booster later in the fall?



Michele writes:

Hi Dr. Griffin,

I was told by my nephrologist that if I should get Covid (which I have not yet had), I should take the renal dose of Paxlovid.  I am 64 years old and have mild, stable kidney disease.  Are there any studies that compare the effectiveness of the renal dose of Paxlovid with the regular dose in terms of severity of disease and keeping people out of the hospital?  Based on any research you know of, might Remdesivir (I live in NY) be a better option than the renal dose of Paxlovid?