By my rough estimate, I've been in my private rabbit hole of infectious diseases and microbiology for over 50 years. Certainly covid has prolonged my stay. This past week I saw a number of new publications that are worth mentioning, I'll try to be succinct!
Tripledemic Tracking
After pausing for data entry to somewhat catch up after the holiday lull, let's look at the landscape.
Influenza
According to FLUVIEW, the country as a whole is seeing continued decline in flu cases. Remember I'm showing you just the hospitalizations confirmed to be flu, as a most accurate tally. Note that the dashed line is to call attention to the lag in reporting the past few weeks. Let's hope we don't see a rebound.
COVID-19
Percent positivity continues to rise, but a little tougher to determine accurate infection rates given all the nuances we've discussed recently.
The XBB.1.5 variant continues to hold the lion's share of the variant proportion in the US. I was interested to see that, at least so far, this variant is not a big deal in the UK. I expect that to change.
RSV
RSV-NET shows a continued decline in RSV infections, with the caveat that we might still be experiencing delayed reporting from the holidays. I don't expect RSV to trouble us any more this winter.
More on Long Covid
A new analysis from Israel suggests that most symptoms of long covid tend to resolve at 1 year follow-up for those individuals who had mild covid illness originally. This is an analysis from a large database which can have its own misleading reporting issues, but in the past this same database has had a good track record for being correct.
Bivalent Covid Vaccine Boosters No Better Than Monovalent?
Two small studies (here and here) in last week's NEJM suggest this is the case, from comparisons of antibody responses. I first commented on these studies last October when they were only in preprint form. Note these studies did not include children, so we could see some different results when those analyses are performed. The accompanying editorial by Paul Offit is a good read. It is essentially an "I told you so" discussion. Some may recall that he was the only member of the FDA VRBPAC panel last summer who voted against moving forward with the bivalent boosters. His main argument was that we didn't know if they were any better than monovalent boosters against the emerging variants, and these small studies appear to confirm his suspicions.
Please be aware this doesn't mean that bivalent boosters are worse, just that they may be no better than boosting with the monovalent vaccine, at least for now. Stay tuned for what should be a very stimulating discussion of future vaccine plans at the next FDA VRBPAC meeting on January 26.
A Clue to Myocarditis Mechanism Following Covid Vaccine?
Researchers in Boston reported results from 61 adolescents and young adults (16 who developed myocarditis and 45 who did not) who had received either the Pfizer or Moderna mRNA vaccines. They found an association of circulating spike protein in blood samples with the myocarditis group. They also looked at immune and cytokine patterns in the subjects. The discussion portion of the article brings up many possible explanations for how intact spike protein might be involved in the pathogenesis of myocarditis, but this is all very preliminary. Now we need more studies to confirm this association and further explore the immunologic phenomena accompanying it.
Note that nothing in this study changes the bottom line for vaccine advice: benefits of covid vaccination outweigh risks when we are considering myocarditis or any other endpoint for COVID-19.
Everything Old is New Again
No one seems to know definitely who first coined this phrase, but I mention it here to remind all healthcare providers to be on the lookout for those "old" vaccine-preventable diseases such as measles, mumps, rubella, and even diphtheria. This week the CDC gave us figures for vaccination rates in kindergarteners during the 2021-22 school year: not encouraging, but also not surprising. Another publication provided some some explanation for why we see problems with mumps outbreaks even in fully vaccinated adolescents and young adults. (Spoiler alert, it is waning immunity.) If any healthcare provider is a little fuzzy on diagnosis and management of these diseases, please review!
Speaking of old, I found that Alice's Adventures in Wonderland was published in 1865, and Down the Rabbit-Hole is the title of the first chapter. Maybe I'll reread it one of these years.