The Latest on Baloxavir, Concurrent Diagnoses for Adults with the Influenza, and Other Flu News

The US Centers for Disease Control and Prevention (CDC) reported a sharp decrease in influenza activity confirmed by clinical laboratories in their final FluView report of the season.

The CDC added that because of the continued effects of the COVID-19 pandemic on outpatient influenza-like illness, the agency would continue to monitor the flu but put out less frequent reports, and the agency will instead issue COVIDView.

The H1N1 virus is the most commonly reported strain of flu this season, the CDC added. There was a drop in visits to health care providers for influenza-like illness from week 13 to week 14, from 5.2% to 3.9%, respectively.

The total number of pediatric deaths linked to the flu increased to 166 for the season, the CDC said. Hospitalization rates for children were higher this season than any recent regular season, but the rate still remains lower than that experienced by this age group during the H1N1 pandemic of 2009, the report continued.

The CDC said that for the 2019-20 flu season so far, there have been at least 39 million flu illnesses, 410,000 hospitalizations, and 24,000 flu-related deaths. Additionally, almost all of the flu viruses tested this season were susceptible to the 4 antiviral medicals recommended for use this season that were approved by the US Food and Drug Administration.

Pneumonia, sepsis, and acute kidney injury occurred frequently among adults hospitalized with influenza, according to a paper published in JAMA Network Open. The study authors used data from the 2010-11 to 2017-18 flu seasons to observe nearly 90,000 influenza-confirmed patients and determine their respiratory and non-respiratory diagnoses. Nearly all of the patients (95%) had a respiratory diagnosis, while 47% had a non-respiratory diagnosis, and 5% had only non-respiratory diagnoses. The most common acute diagnoses were pneumonia (36%), sepsis (23%), and acute kidney injury (20%).

“Nonrespiratory diagnoses occurred frequently among adults hospitalized with influenza, further contributing to the burden of infection in the United States,” the study authors wrote. “The findings suggest that during the influenza season, practitioners should consider influenza in their differential diagnosis for patients who present to the hospital with less frequently recognized manifestations and initiate early antiviral treatment for patients with suspected or confirmed infection.”

Flu vaccines were associated with reduced risk of respiratory morbidity and mortality in people with autoimmune rheumatic disease (AIRDs), according to a paper published in Rheumatology. The investigators collected data from 30,788 AIRD patients and found that flu vaccines reduced the risk of influenza-like illness, hospitalization for pneumonia, chronic obstructive pulmonary disease exacerbations, and death due to pneumonia in this population.

A study published in PLOS Pathogens showed that baloxavir reduced the transmission of H1N1 flu virus from infected ferrets to healthy ferrets. In prior research, baloxavir was shown to be more effective in reducing viral shedding compared to the widely used oseltamivir.

In their study, the investigators compared baloxavir to placebo and oseltamivir to placebo to see what was the most effective in reducing community-based spread of the flu among ferrets. Baloxavir won.

The study authors believe baloxavir could slow the spread of flu outbreaks by limiting community-based spread, according to a press release. They also think that their findings can dramatically change how the world manages pandemic influenza.

“Our study shows that baloxavir can have a dual effect in influenza: a single dose reduces the symptoms and reduces the risk of passing it on to others as well,” they concluded.

A further study of ferrets in PNAS found that among ferrets, there as a risk for transmission of baloxavir-resistance viruses from treated individuals. They tested influenza A and B viruses with baloxavir resistance to assess the risk of any emerging resistance.

The FDA announced in March that they accepted a supplemental New Drug Application for baloxavir for use in children aged 1 to 12 years with influenza. Marketed as Xofluza from Genentech, the drug could be a more convenient option for children and those with trouble swallowing, according to a press release.

A second supplemental new drug application for Xofluza was also accepted by the FDA for use as post-exposure prophylaxis of influenza in people older than 1 year old. The FDA is expected to make a decision on both of these approvals in November, the statement added.

And in other flu news:

• Contagion® reported that an experimental vaccine called FLU-v decreased the chance that those who received it would develop flu symptoms and viral shedding. Read more.
• Contagion® also reported that measured vaccine effectiveness can have intra-seasonal decreases for the influenza vaccine. Read more.
• And finally, Contagion® reported that there is zoonotic potential in the newly-isolated H16N3 Avian flu virus. Read more.