The end of the official Covid emergency now potentially hindering bird flu outbreak analyses.
When the US government officially ended the Covid-19 public health emergency (PHE) in 2023, it meant that detailed hospital reporting requirements enacted during the pandemic would eventually also be sunsetted. That finally happened earlier this year. As a result, today we know a lot less about the real-time state of US hospitals now than we did during the Covid-19 PHE.
The degradation in public data is now starting to hinder my ability—and I assume that of other public health experts—to monitor important situations, such as in Colorado, where some farm workers have been diagnosed with H5N1 influenza (i.e., bird flu).
So far, the CDC has reported four cases of H5N1 in Colorado (and possibly a fifth). But testing is extremely limited, and nobody is testing for asymptomatic disease, a massive mistake Dr. Harlan Krumholz and I similarly called out early in the Covid experience. Former White House Covid-19 Response Coordinator Dr. Deborah Birx (who has become a friend and resource for me) agrees; she often says that when public health officials detect a single case of a highly transmissible virus, we need to assume there are 10, if not 100 more out there flying under the radar.
Just how many cases of H5N1 are out there? It’s impossible to know. Only far more asymptomatic testing (or rigorous random population sampling), pooled testing, or wastewater surveillance could even begin to overcome our current ignorance on this. There could be a few cases out there or there could be many.
Hospital data can provide outbreak insights.
Hospital data could help. While hospitals only test people who come in for testing and treatment, that information can sometimes be very important in detecting a new outbreak.
Now, it’s important to realize that hospitals are not always canaries in the coal mine for community outbreaks. For example, if Covid-19 had been spreading on a college campus in January of 2020, there might have been so few hospitalizations in that age group that it might not have registered as an increase in respiratory illnesses in hospitals if most cases were mild. Only after enough students spread it to older people—perhaps their grandparents during a visit home during spring break—would hospitals see an uptick in respiratory illnesses and admissions. This tracking is called syndromic surveillance. That said, it apparently only takes a very small change in certain patterns to alert the CDC that something unusual is amiss.
The time it worked…
A superb example of syndromic surveillance in action was the CDC’s detection of e-cigarette or vaping use-associated lung injury (EVALI), which was later determined to have been caused by illegal devices modified (by including Vitamin E acetate) to make it possible to vape marijuana. (I am not aware of any EVALI cases that are known to have been caused by regular legal vaping devices.) Back in 2019, local officials in Illinois and the CDC noticed that among male patients, the rates of severe unexplained respiratory illness among males ages 14-30 doubled, from around 6 per 10,000 emergency room visits to 12 per 10,000. That is a very small number of cases upon which to launch an investigation. But it was enough, and EVALI was eventually uncovered. Go public health and epidemiology!
If something's happening in northern Colorado, the public can’t track it.
One of the positive developments to come during the Covid-19 pandemic was that the US Department of Health and Human Services required hospitals to provide daily updates on a slew of key metrics. Those data were public and included the number of Covid-19 patients that were in each hospital as well as overall capacity numerators (the number of hospital beds that were filled) and denominators (the total number of hospital beds that could possibly be staffed and occupied by a patient) in thousands of hospitals across the land. That meant that even if hospitals weren’t testing for Covid-19 (a problem early on in the pandemic), officials and the public could get a pretty good idea of what was going on by looking at hospital capacity data. The data were granular down to the level of individual facilities. These data were crucial for our circuit breaker dashboard during the initial Omicron outbreak.
But today, with the Covid-19 PHE reporting requirements now gone, we don’t have the ability to look at hospital metrics in northern Colorado, where there are currently a large number of animals with bird flu, and an unknown number of human cases.
Per Inside Medicine data analyst Benjy Renton, there are exactly two hospitals that serve Weld County, CO, the location of the bird flu cases the CDC has reported. A year ago, we could have told you if these hospitals were having an unusual uptick in the number of people hospitalized. Today, we know nothing.
Reader, I think that’s a massive problem. And perhaps the CDC is looking at these facilities, monitoring for any sudden changes in respiratory illnesses that could represent H5N1 cases that are not being detected. But the problem is that we really do not know the clinical features of H5N1. I can’t emphasize this enough. So far, we’ve heard that the cases are mild. But what does this disease look like in older or frail people? It could be that the population has some immunity to this virus (which would be a good thing, overall), due to prior exposure to H5 viruses that are similar enough to have left those with prior infections with protection against severe pneumonia or respiratory symptoms. But people with serious medical problems can have their health profoundly affected by a nasty virus, despite having some immunity to, be it influenza or Covid-19. Remember, most deaths from Covid-19 these days are what I call “tip-over” deaths, rather than pneumonia. These deaths can look as diverse as the array of serious medical problems we commonly treat, from diabetic crises to heart failure. So, it might be hard for the CDC to detect an uptick in any one type of problem—though we hope they would notice if all-cause hospitalizations suddenly increased.
Of course, if we still had hospital-level data that included patient census and capacity for all care as we did during the Covid-19 emergency period, we wouldn’t have to wonder. We could just check it ourselves.
Thanks to Benjy Renton for the data and image on Colorado hospitals.
CDC and overall public health policies regarding COVID have largely been driven by preferences of the American Hospital Association and CEOs of large corporations (see e.g. https://rollcall.com/2020/03/13/hospitals-want-to-kill-a-policy-shielding-nurses-from-covid-19-because-there-arent-enough-masks/ and https://www.npr.org/2021/12/29/1068731487/delta-ceo-asks-cdc-to-cut-quarantine) since January 2020. H5N1 policies follow the same pattern.
Hospital executives do not like the reporting requirement so it ended. Agribusiness do not want their workers tested for H5N1 (or their animals, until it becomes absolutely unavoidable), so they aren't. Farmworkers are afraid of losing their jobs, so they avoid involvement with the medical system.
Other than advocating for vaccines, is there any difference between the CDC under the Biden administration, and that under Trump? (And absolutely yes, these administrations were vastly different in other respects.)
The lack of data regarding bird flu isn’t really surprising, even if disappointing. Consider that the last several years have seen a steady decline in available and/or useful information about COVID. First test data became meaningless since test reporting dwindled, then hospitalization data became less meaningful with reporting requirements disappearing after the expiration of the public emergency order as you point out in your comments. Then the only real measure of how serious the disease continued to be became the actual numbers of people dying. But then the CDC began making those numbers harder and harder to find - and publishing only numbers per 100,000 and even showing only the changes in those numbers, rather than the actual numbers of deaths. Then people searching for the absolute numbers were referred to reports of deaths from all causes which lagged by weeks and even months. But the CDC continued, and continues, to report the number of deaths per 100,000 without clarification of whether those figures and the changes in them were generated from the lagged reporting database or some more relevant source that the CDC was choosing to not make available to the public.
I think that the lack of candor and transparency and urgency by the CDC with regard to COVID data has itself contributed significantly to a general lack of interest in gathering information on bird flu. That information should be collected, but playing down the ongoing risks of Covid to avoid “political blowback” has encouraged an attitude of “what, me worry” and brought us to where we are now.