Pere writes:

Hello Daniel & Vincent,

Thank you for your updates! I’ve been an avid listener since June 2020 (found about you late!) and as many people have said, you’re a lighthouse in these mad seas!

I’ve come with a questions about IVIg therapy and COVID (obviously)

My daughter is a kidney transplant recipient and has also recently been through a lymphoma and barely has any B cells thanks to Rituximab.

She’s however on IVIg therapy and I’m wondering… would that now confer some level of immunity against COVID?

I’ve found a few papers commenting that there are now COVID19 antibodies in common IVIg ( , ) but I haven’t been able to find any kind of information about if they confer any level of “real life” protection.

I guess that in an ideal world she would be a recipient of prophylactic COVID19 mAb cocktails, but unfortunately we don’t live in the USA and they’re not generally available where we live.

Thanks very much for your great work and help!


— p.

Ron writes:

I have experienced daily headaches since I had an unusual virus in early March of 2020 (mild fever, headaches, sore throat, shortness of breath, NO coughing).  A PCR test for Covid-19 at the time was negative, but I’ve wondered whether my persistent headaches could be a result of “long Covid.”  I’ve been fully vaccinated since April of 2021.  I recently had a T-Detect test, after hearing about it on this

channel.  My result has come back positive, but the accompanying comments include: 

  “The clinical significance of a positive adaptive T-cell immune  response to SARS-CoV-2 result for individuals that have received a  COVID-19 vaccine is unknown.” 

The website says:

  “We do not currently have information on how the SARS-CoV-2 vaccine  may affect the T cell response and the results of the T-Detect COVID  test…”  

Obviously knowing whether vaccination affects the results of the test is important in determining how to proceed.  Can Daniel shed any more light on this subject? 

Thank you very much.


Jean writes:

Hello from London where it is a lovely 22 degrees. The morning started quite humid but the sun is burning through those clouds now and it looks like it’s going to be a lovely day. 

I am a non scientist who has been very covid / sars-cov2 curious since the early days of the pandemic. I found Dr Daniel Griffin via the Brian Lehrer Politics podcast months ago and since then have been listening to all episodes of TWIV regularly. I love how you dive deep and explain things. Especially how you analyse the studies and it has taught me how to be a critical consumer of science in media, and not just relating to covid. I never use the B word or the words viral load. I distinguish infection from disease. I have been thinking of writing for months to tell you how much I appreciate your cautious, measured approach and explanations. It has helped me enormously to calm my pandemic anxiety. 

But I did just want to say that as well as following virologists, epidemiologists and clinicians for science info, I have been following chemists and experts in fluid dynamics to understand more about the idea of airborne transmission. And on that topic I’d like to say it’s carbon DIoxide that we need to measure for indoor air quality relating to covid. Of course carbon monoxide would also also be a serious concern for air quality 😱. I have implemented CO2 monitoring at my office as a proxy for understanding ventilation levels. It’s part of our layered mitigations which include vaccination, masking, hand and respiratory hygiene, reminding people to stay home if unwell. 

As a mum of a 14 year old, I’m so jealous that the vaccine has been rolled out to adolescents in the US. We are about to return to school with no bubbles, no masks, no vaccination for under 16yo, no vaccine mandates for staff. They have removed the isolation required for close contacts if you are double vaccinated or under 18. I think we are in for a rough winter. I wish people would listen when Daniel says “children are at low risk but they are not a no risk.”

Thank you for all that you do. 

Oh yes I must add that I am also grateful for your regular acknowledgment of the “long covid / post covid”.

Stay safe and well. 

Yours sincerely,


Thomas writes:

First thank you to you for sharing your insights on how you are managing COVID in the US and to Dr Racaniello for reminding me of how viruses interact with our immune system.  I would like your thoughts about the anticoagulation issue you spoke about in the last clinical update where the one arm of that paper in NEJM for critically ill patients showed no benefit with therapeutic anticoagulation, but the other arm (which wasn’t highlighted in the update) of non critically ill patients (which would be a larger proportion of hospitalized patients) did see benefit with therapeutic dosing of LMWH.

As quoted from the paper itself:


In noncritically ill patients with Covid-19, an initial strategy of therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support as compared with usual-care thromboprophylaxis.

What is the standard of care for non critical COVID 19 hospitalized patients in your community as it relates to anticoagulation?

Dr. Thomas Tam

Calgary, Alberta