Ginny writes:
Hello,
I receive the excellent newsletters from Katelyn Jetelina, Your Local Epidemiologist. In the most recent one, she answered a question like this.
If my Covid antigen at-home test is positive for a long time (14, 21, 28 days), am I still contagious?
Unfortunately, we don’t have good data on this. But, most likely, you’re still contagious. Covid-19 antigen tests are very good at detecting infectious Covid-19 virus. (PCRs, conversely, are good at telling whether you have the virus, regardless of infectiousness.) Be sure to wear a mask.
Is that right? And since antigen tests detect protein, are they “very good at detecting infectious virus”? I thought you needed something like a plaque assay for that. (See, I’ve been paying attention!) Or is it that you won’t get the protein unless the virus is active? I thought the antigen test might see remnants even after the virus is no longer active.
Thanks for all you and Vincent do. I’ve learned so much.
Ginny
Rochester, NY
Mike writes:
Hi Daniel,
Wrestlers and martial artists sometimes need to worry about things like ringworm and herpes gladiatorum. Do you think eventually we’d need to worry about mpox as well?
Mike from Boston
Alec writes:
Dear Dr. Griffin,
Greetings from Cambridge, Massachusetts. Hearing the letter about mRNA vaccine disinformation in last week’s clinical update motivated me to write you. My partner recently got covid for the first time. She is 67 years old and healthy. We both had gotten paxlovid prescriptions last winter (with difficulty) in advance of traveling, so she was able to start paxlovid after her first positive test. Thankfully, after a couple of bad days she is feeling much better.
Our neighbors warned her about paxlovid rebound. Being a faithful listener of the TWIV clinical update, I said confidently that paxlovid rebound is not a thing. She googled paxlovid rebound and the first result was a blog post for laypeople from a medical school in our area that you may have heard of, titled “Paxlovid rebound: what you need to know, written May 9, 2024.” It defines paxlovid rebound, and has sections “How to know if you’re experiencing Paxlovid rebound” and “Managing Paxlovid rebound.” In short, it treats paxlovid rebound as real. Buried in the 9th paragraph it says “For people at high risk of getting very sick or dying from COVID-19, the benefits of Paxlovid far outweigh any risk of a rebound.”
It mentions the large clinical trials you often cite that showed no evidence for paxlovid rebound (with a broken link). The only evidence of paxlovid rebound is “a small, observational study from Harvard Medical School.” The first sentence of the results section of this paper is “Compared with untreated persons (n = 55), those taking N-R (n = 72) were older, received more COVID-19 vaccinations, and more commonly had immunosuppression.”
I’m shocked that one of the most famous medical schools in the world would publish an article that might discourage people from taking a potentially life-saving treatment based on a concern that probably is not real. What is to be done?
Thanks to you, Vincent and the rest of the TWIV team for all you do.
Regards, Alec
Carmen writes:
Thank you TWIVers,
I have been a regular listener from Tennessee for a few months.
My son, now a 28 year old NYer, was exposed to TB in South Africa at 7 years old when his father took him for a prison visit as well as staying in the townships. He had a big new positive PPD about 4 months later and he could not take the INH because of bizarre hyper behavior changes. He has been healthy since.
If that TB exposure were to become a health issue for him, what ID team in NYC would do appropriate tracking of TB resistance to factor in to treatment for him?
Been thinking to ask for a while.
Thank you
Carmen
Connie writes:
Hi Daniel and Vincent,
Thanks again for your invaluable podcasts. I recently read in Katelyn Jetelina’s newsletter that it might be beneficial for people to get a pertussis vaccine every ten years. She wrote, and referenced an article from the UK, that the pertussis vaccine that’s been used for decades loses its effectiveness over time, more so than expected.
Can you give us any information about this ?
I’m 75, and got a TDaP booster shortly before my oldest grandchild was born in 2016. Do I need another one in the near future ?
Thank you for any light you can shed,
Connie