Some people cannot go on too many cruises, finding it the best way to leave the workaday world, log some travel miles and breathe balmy ocean air.

Others — perhaps unfairly — can’t get past occasional news reports of cruise ships waylaid by norovirus outbreaks. Passengers get felled by vomiting and diarrhea. Vacations are ruined faster than the time it takes to say, “I don’t feel so good.”

A National Institutes of Health study found a class of viruses that cause several diseases, including norovirus and rotavirus, can grow in the salivary glands of mice — and be spread to one another through their saliva.

That’s a big change from what scientists had believed, that the viruses are shed solely through the feces of one host and consumed via food or drink by another, replicating in that host’s intestines, shed via their feces and the cycle repeated — forgive the pun — ad nauseam.

The researchers haven’t yet confirmed that the enteric viruses spread through human saliva. But if they do, it would greatly aid virus mitigation. The viruses can hit nursing homes, schools, hospitals and other places humans congregate.

The saliva-transmission finding came almost by luck. The researchers had been conducting enteric-virus experiments using infant mice, whose digestive and immune systems are vulnerable.

The mice pups were fed the virus, then suckled their virus-free mothers. The researchers soon realized that suckling led to mother-to-pup and pup-to-mother transmission. The finding means that talking, sneezing, kissing and generally just being close may spread the viruses. It could eventually mean a lot less suffering worldwide — and smoother sailing. Bon voyage!