A new study has found that a single dose of an antiviral medicine called baloxavir marboxil can lower the chance of passing the flu to family members by about 30%.
This research was published in the New England Journal of Medicineand led by Dr. Arnold Monto from the University of Michigan, an expert in infectious diseases who has long advised U.S. health organizations like the CDC and the FDA.
Flu is a highly contagious virus that can easily spread among people living in the same home. While flu medicines have been available for many years to help people recover faster, it was not clear if they could also stop the virus from spreading to others.
No earlier studies were specially designed to answer this question. The new research, called the CENTERSTONE trial, finally set out to find the answer.
In the study, researchers worked with 1,457 people between the ages of 5 and 64 who had tested positive for influenza. They also included 2,681 family members who lived in the same household.
The sick patients were randomly given either baloxavir marboxil, which is sold under the brand name Xofluza, or a placebo that had no active medicine. The researchers then closely monitored the family members to see if they caught the flu.
The results showed that those who received baloxavir were much less likely to spread the flu to their family members compared to those who received the placebo. This suggests that baloxavir does more than just help the sick person get better faster—it can also help protect others from getting infected.
Dr. Monto said this study answers a long-standing question about whether treating the flu early could also reduce its spread. Before this, it was unclear if antivirals made a difference in transmission or if past studies just weren’t designed carefully enough to detect it.
Thanks to the CENTERSTONE trial, there is now strong evidence that the spread of influenza can indeed be reduced through antiviral treatment.
Dr. Adam Lauring, another author of the study and head of infectious diseases at the University of Michigan Medical School, said he found the study very exciting. He pointed out that if we can use antivirals not just to treat the sick but also to stop the virus from spreading, it could change the way we handle future flu outbreaks in homes and communities.
One important advantage of baloxavir is that it only needs to be taken once, unlike other flu medicines that must be taken daily for five days. Dr. Monto said that a single-dose treatment might encourage more people to get treated quickly, not just to protect themselves from serious illness, but also to protect their loved ones.
He explained that treating flu patients early could give a “two-for-one” benefit: making the illness shorter and less dangerous for the patient, and at the same time lowering the risk of spreading it to others. This could help prevent serious complications that sometimes lead to hospital stays or even death.
Interestingly, baloxavir might also help in the fight against other types of flu, such as avian flu. Although baloxavir has not yet been tested in birds or cattle, laboratory studies have shown that it can stop these viruses from making copies of themselves. This raises hope that baloxavir could someday be useful in stopping the spread of different kinds of influenza.
In reviewing the study’s findings, it is clear that baloxavir marboxil offers real promise not just for helping individuals recover faster from the flu, but also for slowing down the spread of the virus in homes and communities.
The fact that it only requires one dose makes it more practical and easier for patients to use compared to older treatments. This could lead to wider use of antivirals during future flu seasons and even during new influenza outbreaks. Overall, this research could mark an important shift in how we think about treating and preventing the flu.
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The research findings can be found in the New England Journal of Medicine.
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