BUCKEYE, Ariz. — Wash your hands, cover your mouth and don't share water bottles. 

That's the advice the Litchfield Elementary School District in the West Valley is sharing with parents after seeing an increase in cases of pneumonia at Verrado Elementary School in Buckeye. 

Thirty-one students are affected. 

"In light of an increased number of children with pneumonia at its “A” rated Verrado Elementary School, the “A” rated Litchfield Elementary School District is taking extra steps to promote good health habits," a Thursday press release said. 

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Pneumonia is a lung infection with symptoms that include chest pain when you breathe, fever, sweating, nausea, diarrhea and shortness of breath.

"Most likely it’s caused by a bacteria called mycoplasma pneumonia --- we actually confirmed that in one of the cases today. This infection spreads from one person to another when someone coughs or sneezes," Dr. Rebecca Sunenshine with the Maricopa County public health department said.

School officials consulted with experts from the Maricopa County Department of Public Health and established good hygiene is the best way to keep illnesses from spreading. 

"It's so important for parents to teach their kids to cover a sneeze with a tissue and make sure they wash their hands afterwards and wash their hands before they eat," Sunenshine told 12 News. 

Every classroom has a hand washing station. And teachers and custodians have been asked to be more diligent about sanitizing desks, doorknobs and other classroom surfaces. 

"We want to make sure the school has an adequate number of hand washing facilities, and make sure there’s soap and hand sanitizer and the facilities are disinfected appropriately," Sunenshine said.

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