This clinical update from Drs. Daniel Griffin and Vincent Racaniello covers a range of current virology and public health topics, with a strong emphasis on the negative impacts of science denialism and political interference. The hosts are highly critical of the CDC's updated language on its vaccine-autism webpage, which they describe as a scientifically disingenuous and dangerous concession to political pressure that will fuel vaccine hesitancy.
Global surveillance updates include the detection of wild-type poliovirus in German sewage, the first Marburg virus outbreak in Ethiopia, and the decimation of an elephant seal colony by H5N1 avian flu. The discussion details the first human H5N5 case in the US, linking it to research on the virus's transatlantic spread and adaptation to mammals.
The domestic respiratory virus outlook is grim, with rising measles cases threatening the country's elimination status, and warnings of a potentially severe flu season due to a likely vaccine mismatch with the circulating H3N2 subclade K. The hosts also review new data on the high efficacy of RSV monoclonal antibodies for infants and the greater risk of Guillain-Barré syndrome from RSV infection versus vaccination. COVID-19 topics include the high risk of airborne transmission in shared hospital rooms and a skeptical analysis of a study on resistance exercise for Long COVID. The episode concludes with a Q&A session addressing practical clinical questions.
TWiV 1272 Clinical Briefing: CDC Under Fire, Global Outbreaks, and Winter Virus Outlook
2:38 Politicization of the CDC: The hosts are dismayed by changes to the CDC's vaccine-autism webpage. They label the claim that "vaccines do not cause autism" is not "evidence-based" as a disingenuous play on words, as proving a negative is impossible with observational studies. They view this as a dangerous concession to anti-vaccine activists that undermines public trust.
9:28 Polio Detected in Europe: Wild type poliovirus 1 (WPV1) was found in German sewage, likely imported from Afghanistan or Pakistan. The risk is assessed as low due to high vaccination rates, indicating that surveillance systems are working.
11:25 First Marburg Outbreak in Ethiopia: An outbreak of Marburg virus disease, a filovirus related to Ebola, has been confirmed in Ethiopia, with nine cases and six deaths reported. The reservoir is the Egyptian fruit bat.
13:37 H5N1 Decimates Elephant Seals: Highly pathogenic avian influenza (H5N1) has caused mass mortality in the world's largest southern elephant seal breeding colony, resulting in a 47% decline in breeding females.
16:48 Human H5N5 Infection in the US: The first human case of H5N5 avian flu in the US was reported in an older adult in Washington. The hosts link this to research showing the virus's transatlantic spread via seabirds and the presence of the PB2 E627K substitution, which may aid in mammalian adaptation.
27:42 Measles Elimination Status Threatened: The US and Canada are experiencing a significant rise in measles cases, with thousands reported. The hosts attribute this resurgence directly to anti-vaccine misinformation.
30:23 Warning of a Potentially Severe Flu Season: An emerging H3N2 variant (subclade K) is circulating globally and appears to be a mismatch for the current vaccine, which targets subclade J. A bad flu season is expected; despite predicted lower efficacy, vaccination is still critical to reduce disease severity.
36:52 RSV Updates on Prevention: An MMWR report confirms that the monoclonal antibody Nirsevimab is approximately 80% effective at preventing RSV-associated ICU admission in infants. Separately, data shows the risk of developing Guillain-Barré Syndrome (GBS) is significantly higher after an RSV infection than from the RSV vaccine in older adults.
45:42 High Airborne COVID-19 Risk in Shared Rooms: A study found a secondary COVID-19 attack rate of 26.3% in shared hospital rooms. This underscores the high risk of airborne transmission and the insufficiency of surgical masks or privacy curtains as protective measures.
48:24 Questionable Benefit of Resistance Exercise for Long COVID: A clinical trial showed a statistically significant improvement in walking distance for Long COVID patients undertaking resistance exercise. However, the effect was small and the error bars were large, making the clinical significance of the finding debatable.
51:59 Clinical Q&A Insights:
Feeling very sick after finishing Paxlovid is likely the body's inflammatory response to the virus, not a "rebound."
Adults born before 1957 are presumed to be immune to measles from natural exposure and likely do not need additional vaccination, even if they only received one shot in the 1960s.
COVID-19 is more severe than influenza, particularly regarding post-viral sequelae. For prolonged patient contact, an N95 mask offers substantially more protection than a surgical mask.
To ensure an effective immune response, COVID/flu shots should be administered at least three weeks before receiving a cortisone injection.
A severe shoulder injury following vaccination (SIRVA) is typically caused by improper injection technique where the vaccine is administered into a tendon or bursa instead of the deltoid muscle.