Alabama Sen. Tommy Tuberville and four of his Republican colleagues on Friday urged President Biden to ban travel from China as health officials grapple with understanding a so-called “mystery illness” there.

Tuberville and the four other Republican senators said they were skeptical of China telling World Health Organization officials the truth about the cluster of respiratory illness detected in the northern part of the country that is mostly plaguing children after the COVID-19 pandemic.

“We must take the necessary steps to protect the health of Americans, and our economy,” the senators wrote in a letter to Biden on Friday. “That means we should immediately restrict travel between the United States and the PRC until we know more about the dangers posed by this new illness. A ban on travel now could save our country from death, lockdowns, mandates, and further outbreaks later.”

Tuberville and Sen. Marco Rubio, R-Fla., spearheaded the letter, while Republican Sens. J.D. Vance of Ohio, Rick Scott of Florida and Mike Braun of Indiana signed on to the missive.

The senators said China has “a long history of lying about public health crises,” including during the pandemic, claiming the country’s “obfuscation of the truth, and lack of transparency, robbed the United States of vital knowledge about the disease and its origin.”

“The WHO has requested that the CCP [Chinese Communist Party] share ‘detailed information’ about the mystery illness,” the senators wrote. “However, CCP has an incentive to lie, just as they did throughout the COVID-19 pandemic and any new pathogen could derail its efforts to stimulate its economy. Besides, we should not wait for the WHO to take action given its track record of slavish deference to the CCP.”

The WHO said the symptom’s observed in the current outbreak “are common to several respiratory diseases and, as of now, at the present time, Chinese surveillance and hospital systems report that the clinical manifestations are caused by known pathogens in circulation.”

The agency said China attributed the upsurge in respiratory illness to “lifting of COVID-19 restrictions and the arrival of the cold season, and due to circulating known pathogens such as influenza.”