Credit CDC
Note: After 18 hours without internet due to Hurricane Helene (which passed well to my west), I'm back online, none the worse for wear. Sadly I can't say the same for millions of others who took a much more direct hit.
#18,321
The on-going saga of symptomatic contacts with the Missouri H5 case from last August continues this afternoon with the revelation in this week's CDC H5N1 update that Missouri has notified them of 4 more symptomatic Health Care Workers who were in contact with the index case.
As you'll recall, two weeks ago we learned of Two Symptomatic Contacts; one a close family member, and the other a HCW. The family member was not tested, and the HCW tested negative for influenza (test type not specified).
A week later (Sept 21st) a 3rd Symptomatic Contact Announced, again an HCW, who was not tested.
Today, more than a month after the index case was hospitalized, and > 3 weeks since the index case was confirmed with HPAI H5, we learn of 4 more symptomatic HCWs. Unfortunately, no timely PCR testing was done on any of these cases.
Admittedly, given the delays in identifying the index case, by the time the state's epidemiological investigation was launched it was probably too late to do effective PCR testing. Hopefully serological tests (still pending) will shed more light on these cases.
It is entirely possible - perhaps even likely - that these respiratory infections were unrelated to the H5 case. But the optics on this are bad, and getting worse with every delayed revelation.
The following is part of this week's CDC update. Follow the link to read it in its entirety.
Missouri Case Update
Missouri continues to lead the investigation into that state's only reported H5 case with technical assistance from CDC in Atlanta. As CDC learns new information from Missouri about its investigation, we are sharing it as quickly as possible in this space to help keep the public up to date. The Missouri Department of Health and Senior Services has not, to date, identified ongoing transmission among close contacts of the case, first reported on September 6, 2024.Missouri identified two health care workers who were exposed to the hospitalized case before droplet precautions were instituted (i.e., higher risk exposure) and subsequently developed mild respiratory symptoms (among 18 workers with this higher risk exposure); one tested negative for influenza by PCR, as previously reported, and the second provided a blood specimen for testing by CDC for potential influenza A(H5N1) antibodies.Missouri has since identified four additional health care workers who later developed mild respiratory symptoms. One of these workers was in the higher risk category and provided a blood specimen for H5 antibody testing. Three of these workers are among 94 workers who were exposed to the hospitalized case of avian influenza A(H5) after droplet precautions were instituted (i.e., lower risk exposure); blood specimens for those who became symptomatic have been collected for H5 antibody testing at CDC.Aside from the one health care worker reported to have tested negative for influenza by PCR, the five remaining exposed health care workers had only mild symptoms and were not tested by PCR for respiratory infections. PCR testing would have been unreliable at the time of discovery of these individuals' prior symptoms. The health care worker monitoring effort has been part of the ongoing investigation as previously reported. Results of serology testing at CDC on the positive case and their previously identified household contact are still pending.To date, only one case of influenza A(H5N1) has been detected in Missouri. No contacts of that case have tested positive for influenza A(H5N1). CDC continues to closely monitor available data from influenza surveillance systems, particularly in affected states, and there has been no sign of unusual influenza activity in people, including in Missouri.
