In preparing to deal with outbreaks of three different respiratory viruses, measures include newly approved vaccines for RSV and reformulated COVID-19 shots
Clinical laboratories are the frontline of testing for respiratory infections, and as such, were heavily involved in last winter’s so-called “tripledemic” of Influenza, SARS-CoV-2, and respiratory syncytial virus (RSV). According to a Kaiser Family Foundation (KFF) survey, 38% of US households were affected. Now, federal health officials are taking steps to prevent a repeat tripledemic season, which includes new vaccines for RSV as well as reformulated COVID-19 vaccines.
Dark Daily covered this tripledemic in “Early Appearance of RSV Cases, Combined with Influenza and COVID-19, Raises Concern about Possibility of a Tripledemic During This Flu Season.” We noted how in 2022 the federal Centers for Disease Control and Prevention (CDC) had issued a Health Alert Network (HAN) advisory stating, “Co-circulation of respiratory syncytial virus, influenza viruses, SARS-CoV-2, and others could place stress on healthcare systems this fall and winter.” This was especially true of clinical laboratories that were struggling to keep pace with demand for COVID-19 testing.
The big breakthrough this year is the federal Food and Drug Administration’s (FDA) first-ever approval of RSV vaccines in the US. On May 3, the FDA approved GSK’s Arexvy for use in adults 60 years or older. Then, on May 31, the agency approved Pfizer’s Abrysvo for use in the same age group.
“Older adults, in particular those with underlying health conditions such as heart or lung disease or weakened immune systems, are at high risk for severe disease caused by RSV,” said Peter Marks, MD, PhD, Director of the FDA’s Center for Biologics Evaluation and Research (CBER), in an FDA statement announcing approval of the GSK vaccine. “[The] approval of the first RSV vaccine is an important public health achievement to prevent a disease which can be life-threatening and reflects the FDA’s continued commitment to facilitating the development of safe and effective vaccines for use in the United States.”
A GSK press release notes that a clinical trial is underway to evaluate the vaccine for adults aged 50 to 59.
“The number of elders who die of viral infection every winter in our intensive care units, and also sometimes in the summer, is large—it’s in the tens of thousands of individuals,” pediatrician Ofer Levy MD, PhD (above), an advisor to the FDA, told The New York Times. “Each of these vaccines is a huge win.” Clinical laboratories will be looking for these new vaccines to help protect their customers from tripledemic infections. (Photo copyright: Harvard.)
New Targets for COVID-19 Vaccines
Meanwhile, following a June 15 meeting of the FDA’S Vaccines and Related Biological Products Advisory Committee (VRBPAC) the agency announced that it is advising drugmakers to develop COVID-19 vaccines targeting the XBB 1.5 subvariant of the Omicron SARS-CoV-2 variant.
As of early June, XBB lineages accounted for more than 95% of the SARS-CoV-2 variants circulating in the US, noted a recommendation from the VRBPAC committee. The recommendation also noted that the XBB 1.16 and 2.3 variants are on the rise as XBB 1.5 is declining, but “the protein sequences of XBB.1.5, XBB.1.16, and XBB.2.3 spike protein appear similar, with few amino acid differences. Available evidence suggests little to no further immune evasion from these new substitutions in the XBB.1.16 spike protein compared to XBB.1.5.”
The committee recommended a monovalent vaccine composition in contrast to the current bivalent vaccines, which have separate components targeting the original coronavirus strain and the Omicron variant.
Experts Differ on How Best to Administer New Vaccines
One question is whether the three vaccines—COVID-19, RSV, Influenza—should be given in a single visit or spread out. FDA advisor and pediatrician Ofer Levy MD, PhD, told The New York Times that bundling the shots could result in higher rates of immunization. “Plus, you want to get these shots in arms before the viral respiratory season in the winter,” he said. Levy is Director of the Precision Vaccines Program at Boston Children’s Hospital and Professor of Pediatrics at Harvard Medical School.
However, advisors to the federal Centers for Disease Control and Prevention (CDC) have warned that administering the flu and RSV vaccines at the same time could make both less effective. “I would say, when possible, it might be good to spread them out,” Camille Kotton, MD, Clinical Director of Transplant and Immunocompromised Host Infectious Diseases in the Infectious Diseases Division at Massachusetts General Hospital, told The New York Times. “I remain clinically concerned, especially where influenza vaccine doesn’t engender as much protection as we might like,” she said.
Looking Back at Last Winter
Just how bad was the last triple outbreak? In the KFF survey, 38% of respondents said their households were affected by at least one of the three diseases in the previous month:
- 27% reported someone in their household having the flu,
- 15% reported COVID-19,
- 10% reported RSV, a KFF press release notes.
“News about the three viruses also made some people more likely to take preventive measures such as:
- Wearing a mask in public (31%),
- Avoiding large gatherings (26%),
- Traveling less (20%),
- Avoiding eating indoors at restaurants (18%).”
Additionally, people with compromised immune systems were more likely to take precautions, as were Black and Hispanic adults, KFF reported.
Clinical laboratories will soon have new vaccines to combat another potential tripledemic. Whether people will line up to receive them is another matter.