I've had a wonderful week, just returned from a west coast swing to visit a son and also do some hiking in Death Valley. In the meantime, the infectious disease world soldiers on.
Winter Virus Update
We continue to see good news from RESP-NET, though again with the concern particularly with covid that we don't have accurate case tracking, likely resulting in underreporting. XBB.1.5, as expected, appears to be sweeping westward across the country and is by far the dominant variant east of the Mississippi.
Covid Immunologic Insights
A couple of articles released recently bring up some interesting findings. First, researchers at WHO and multiple other academic institutions around the world performed a systematic review and meta-regression looking at protection from prior infection with or without vaccination against omicron infection. Not surprisingly, protection against infection itself waned very rapidly, but hybrid immunity (combination of prior infection plus vaccination) was relatively long-lasting for protection against severe disease and hospitalization: better than 90% at 12 months following last vaccination or infection. This is somewhat supportive of the proposal for annual covid vaccine boosters, although in practice it will be exceptionally impractical to determine individual prior infection status.
The other article was a detailed analysis of clonal T-cell responses to asymptomatic or mild covid infection, comparing adults and children. It is highly technical, mostly of interest to basic scientists, but I was intrigued by the finding that children did not develop effective adaptive immune responses compared to adults. This has important ramifications for future vaccine development.
More Measles Mess
We are already seeing measles outbreaks around the country, mostly isolated/contained, but given the pandemic-associated drop in childhood vaccination coverage we should prepare to see more. Now, researchers at U. Penn have reported relatively high rates of negative measles serologic testing in parturient patients at 2 Philadelphia hospitals. About 20% lacked protective antibodies to measles, an important finding not only for these patients but also for their newborns. For the babies, it's a bit of mixed news because maternal antibody will block response to measles vaccine in the first 6 months of life but also means that these infants could be unprotected very early in life. The main caveat for interpretation is that measles antibody is only a surrogate of protection from infection and thus we can't assume directly that the 20% rate corresponds to true lack of protection.
20 Mule Team Borax
I have vague memories of a television show, Death Valley Days, from my early childhood. Or, should I say what I do remember are the commercials for 20 Mule Team Borax, a laundry detergent still available today. Its main ingredient is sodium tetraborate, very toxic if taken internally or even used as a topical soak/bath. It's a sad state of affairs that I wasn't surprised that borax is yet another toxic compound advocated for use in the covid era, this time by anti-vaxxers as a bath component to reverse the effects of covid vaccination. Bad idea.
Of course, kicking up the trail dust in Death Valley, I couldn't help but think about health risks and not just from tumbling 5000 feet down the Dante's View trail. Death Valley is coccidioidomycosis territory, so if I develop a respiratory illness within the incubation period (1-3 weeks), I'll remind my physician to keep it in the differential diagnosis!
