Astros relief pitcher Brad Peacock has come down with hand, foot and mouth disease, a team spokesman confirmed to NPR, in Major League Baseball's third known case of the contagious virus this season.

Peacock is home recuperating in Houston, the Houston Chronicle reports, after falling ill while he was with the team last weekend in Boston. He was feeling worse by Monday in Detroit, where the team's medical staff attended to him before sending him home.

Pitchers Noah Syndergaard with the Mets and J.A. Happ with the Yankees both came down with the virus earlier this summer and were placed on the 10-day disabled list.

"I'm not sure why this has become a thing in Major League Baseball this year," Astros manager A.J. Hinch told the Chronicle. "There's a running joke inside about having to sanitize everything, but I'm not aware of any sort of precautions we've taken."

Beyond basic hygiene, there may not be much else that can be done.

"It is a very common virus, which we see every summer," Dr. Camille Sabella, director of the Center for Pediatric Infectious Diseases at Cleveland Clinic Children's, tells NPR, noting that the virus "thrives more in warm, humid conditions."

MLB spokesman Michael Teevan tells NPR the league's medical director has been in contact with the clubs' respective medical staffs to ensure that appropriate steps are being taken to address the virus. Those measures include working with doctors who specialize in infectious diseases to identify potential causes, while sharing best practices to contain the spread.

Syndergaard was the first to be diagnosed, on July 23. The likely source: an earlier appearance at a kids' baseball camp during the All-Star break, MLB News reported.

Hand, foot and mouth disease is most common in settings catering to small children and infants, like a day care, where diapers are changed or little ones are putting unwashed hands in their mouths, according to the Mayo Clinic. It can be spread by contact with an infected person's stool, saliva, nasal secretion or fluid from a blister.

The Mayo Clinic points out that the disease isn't foot-and-mouth disease (also known as hoof-and-mouth disease), "which is an infectious viral disease found in farm animals. You can't contract hand-foot-and-mouth disease from pets or other animals, and you can't transmit it to them."

One week after Syndergaard was put on the disabled list, Happ went home sick before a game against the Baltimore Orioles upon showing signs of the virus.

"Sports teams have close exposure to each other, so any kind of infection is more likely transmitted," Sabella says. As for the pitchers spreading it to others via their curveballs from the mound, "it's conceivable that [the virus] can live on objects for short periods of time," Sabella says. "But the most common route that people get this is through hand-to-hand touching."

Symptoms may begin with fever and sore throat, followed by mouth blisters and a rash on the hands and feet that can also blister.

But Sabella says infected adults often display mild symptoms, or no symptoms at all. Some adults, however, may become sicker if exposed to new a strain.

There is no specific treatment for the virus and it usually runs its course in a week or so.

In July, Yankees General Manager Brian Cashman told MLB News the team was taking a simple step to protect the players: "Obviously getting everybody involved with a lot more hand sanitizers."

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