Can you find out whether you’ve had COVID already? Should you? It depends.
Volume #6 Issue #14 November 16, 2022
ALSO IN THIS ISSUE:
COVID state of affairs: Global deaths down, variant #s up . . . and winter is coming
How common is COVID rebound, anyway?
Waning COVID funding means public health layoffs
New and Noteworthy
Global COVID deaths way down, but we’re still in the soup
Some great news from the WHO this week: Global COVID deaths have dropped 90 percent since February (9,400 a week, down from >75K). That said, the situation in Southeast Asia and the Western Pacific isn’t great. Japan is facing a BA.5 surge. In South Korea, cases have been steadily increasing over the past four weeks, and hospitalizations are rising there, too - but not due to any one variant.
As Your Local Epidemiologist just reported, “for the first time during the pandemic, there are more than 300 sub-variants circulating, and not one is dominating globally.” In the US, BQ.1 and BQ.1.1 together (44%) have now overtaken BA.5 (30%) as the most prevalent variants. BN.1, while still only accounting for 4% of cases here, is growing at a rate that’s concerning. And we’ve still got a bit more than a month before winter officially starts amidst the many (mostly indoor) holiday gatherings.
However, according to an analysis by the University of Washington’s Institute for Health Metrics and Evaluation (IHME), while cases are likely to rise during that season, we shouldn’t see anything like last winter’s gargantuan spike (assuming we don’t get a curveball like the one Omicron threw Thanksgiving weekend last year). IHME projects that by February, US cases will be up by about a third from where they are now, to about a million a day. They estimate that global deaths will rise to about 2,748 a day by that point (compare to 11,000 a day in February 2022 and 1,300 a day today).
So, better than previous pandemic winters? Hopefully yes. Perfect? C’mon. You should know better than to ask that by now.
Is COVID rebound as common as we think? Maybe.
In May 2022, in response to case reports like this one in the NEJM, the CDC Issued a Health Advisory to providers to be on the lookout for “rebound” in COVID patients treated with Paxlovid. Defined as recurrent illness and/or positive test results after a first negative test and the resolution of initial symptoms. “Paxlovid rebound” became a hot topic by mid-summer, with big names like Dr. Anthony Fauci and President Biden experiencing it. Speculation that rebound was “widespread” (whatever that means) was itself widespread, at levels far above those cited in Pfizer’s clinical trial during the Delta wave (2.3% for Paxlovid versus 1.7% for placebo, in a wholly unvaccinated population).
Research on the rebound phenomenon has continued to trickle in since that time, but consensus has yet to be reached. A spring 2022 study of 483 high-risk patients found low Paxlovid rebound rates of 0.8%. A review of all Case Western health records for the first five months of 2022 (during the BA.1/BA.2 wave) reported a 5.9% Paxlovid rebound rate. But, this week, a preprint based on data from August to October 2022 (during the BA.4/BA.5 wave) reported that 19% of patients rebounded with symptoms after Paxlovid - vs. 7% who rebounded despite having never received the drug combination.
Pay attention to that last phrase, by the way - we tend to forget that a non-trivial percentage of folks who get COVID will rebound even without having received Paxlovid. And there’s no consensus on how large that percentage is, either. Some results (like this preprint and this study) indicate that it may be as high as 30% of patients - while other studies come out with numbers much lower.
Commentary: The jury on Paxlovid rebound - and COVID rebound in general - is clearly still out, as this excellent review article in Nature explains. However, let’s not lose sight of the forest for the trees. Any drug that is 81% effective in its target treatment group is still in the very top rank of all drugs. We just need to be aware that there is a 1 in 5 risk of rebound, so regular testing should be continued after symptom resolution.
Food for Thought
Not sure if you’ve had COVID? There’s a test for that.
There aren’t a lot of people left these days who’ve never had COVID. If your uncle tells you next week at Thanksgiving that he thinks he’s one of them, there’s a way to find out - even if he’s vaccinated (which he should be).
Vaccination against SARS-CoV-2 creates antibodies to only one of the virus’s proteins: the infamous spike (S) protein. If you have antibodies to any other SARS-CoV-2 proteins (e.g. nucleocapsid (N) protein), then you had COVID, as those only arise as a result of an infection. (One important caveat: These antibodies decline over time. If you are positive for N protein, you definitely have had a natural infection. If you are negative, you might still have been infected, just a long time ago.)
Right now, there are 10 authorized tests that look for the presence of antibodies to the virus’s N protein. Two of them are point-of-care tests (not authorized for home use), and the rest are available at major US laboratories. However, few physicians seem to know that these tests are available.
But is it even worth knowing whether you’ve had COVID, if you’re not already certain? That is a more complex question.
For most people, knowing you’ve already had COVID isn’t of much clinical use. Yes, it might tell you that you have hybrid immunity - the result of natural infection plus vaccination. If you’ve got that (including a bivalent booster), you have the best available protection against an Omicron breakthrough infection. But, while reassuring, it won’t do much for anything except your mental health. (Which - let’s face it - isn’t trivial.)
But there is one situation in which this knowledge truly matters. For those who are suffering the symptoms of Long COVID but don’t have a test (PCR or antigen) confirmed infection in their health records, an N-protein test may be the only way to confirm they had the virus. And without that confirmation, these folks may not be able to access the treatment they so desperately need.
Quick Hit and Commentary
As we think about the people for whom we are thankful, we think about public health officials. These are folks who were constantly on the forefront of the fight against the virus, and their jobs were not easy. They also toiled amidst criticism from every side - they were doing either too much or not enough.
While we knew that it would happen as COVID funding waned, we were sad to hear that almost 4,000 experts who were hired to help public health departments at the start of the pandemic will be laid off in the coming weeks. Maybe 20% of them will be hired as permanent CDC employees. This will leave public health departments once again understaffed as they handle not only COVID but RSV, flu, Monkeypox, and other infectious diseases.
Commentary: We have said it before - public health funding should not be just for emergencies. Can’t we figure out a way to invest ahead of crises in a cost-effective way?
Happy Thanksgiving
We will be off next week - see you on November 30th. Enjoy a holiday filled with joy, laughter and good food. (And add some testing before and after your gathering!)