A county in Ohio has seen a "large uptick" in child pneumonia cases amid surging respiratory infections in China and some European countries. Health officials say the outbreak has no link to cases in other countries.

A total of 142 cases of pediatric pneumonia have been reported in Warren County, surpassing the county average, the Ohio Department of Health revealed.

"The Warren County Health District has received an extremely high number of pediatric pneumonia cases being reported this fall season. Since August, there have been 142 cases of pediatric pneumonia reported. Not only is this above the county average, but it also meets the Ohio Department of Health's definition of an outbreak. We do not think this is a novel/new respiratory disease but rather a large uptick in the number of pneumonia cases normally seen at one time," the officials said in a news release.

Earlier this month, China reported a nationwide increase in the incidence of respiratory diseases. There were also reports of a mysterious pneumonia outbreak in northern China that "overwhelmed" hospitals with sick children.

Following these reports, the WHO requested China to give more details about the cases. Beijing's health authorities attributed the surge to the sudden lifting of COVID-19 restrictions and said the illnesses were caused by multiple known pathogens. Officials maintained that there was "no detection of any unusual or novel pathogens or unusual clinical presentations."

Mandy Cohen, director of the Centers for Disease Control and Prevention (CDC), told members of Congress on Thursday that the surge in cases in China is not from "a new or novel pathogen" but due to existing viruses and bacteria, including COVID-19 and flu viruses, respiratory syncytial virus (RSV) and Mycoplasma pneumoniae.

Warren County Health officials said they could not find a common thread or a conclusive pattern linking the pneumonia cases reported in the county. The cases were caused by pathogens, including Mycoplasma pneumoniae, Streptococcus pneumonia and Adenovirus.

The average age of the patients is around eight. The most common symptoms are cough, fever and fatigue.

"There is zero evidence that what we're seeing in Warren County has any connection to any respiratory activity in the state, in the country, or in the world," Dr. Clint Koenig, Warren County Health District medical director, told ABC News.

While officials are investigating the cases, they recommend healthcare providers test children with symptoms of cough, fever, and/or fatigue for respiratory viruses, mycoplasma and pertussis.

"As we approach the holiday season when many of us will be gathering together with family and friends, please remember to take necessary precautions to protect your health: wash your hands, cover your cough, stay home when ill, and stay up to date on vaccines," the officials cautioned.