Taiwan's health ministry on Thursday urged the elderly, very young and those with poor immunity to avoid travel to China due to the recent increase in respiratory illnesses there, a move some experts said was ineffective to manage public health risks.

The World Health Organization (WHO) last week requested China provide detailed information on the spike, which a WHO official said was not as high as before the COVID-19 pandemic and that no unusual or novel pathogens had been detected.

Taiwan has been wary of disease outbreaks in its giant neighbour since the Severe Acute Respiratory Syndrome (SARS) outbreak that started in China and killed nearly 800 people globally in 2002-2003.

China, whose government claims democratically governed Taiwan as its own, initially tried to cover up that outbreak.

In a statement released after a weekly Cabinet meeting, Taiwan's health ministry said that due to the rise in respiratory illnesses in China, the elderly, young children and other people with poor immunity are requested not to travel to mainland China, Hong Kong and Macau unless necessary.

If travel is necessary, then people should get flu and COVID vaccinations before going to China, it added.

Shu-Ti Chiou, an epidemiologist at the Health & Sustainable Development Foundation in Taipei, said the advisory would lead the public to mistakenly believe they would not contract respiratory illnesses as long as they did not go to China.

Rajib Dasgupta, an epidemiologist and professor of community health at Jawaharlal Nehru University in New Delhi, also said "travel restrictions for respiratory infections are not an effective measure for interrupting transmission".

Some public health researchers said the travel advisory was reasonable, saying Taiwan was also likely to experience a surge in respiratory illnesses in winter and following the lifting of pandemic restrictions. "They would be cautious not to hasten it by overseas travels," said Sung-il Cho, an epidemiologist at Seoul National University.

China's Foreign Minister Wang Yi said on Wednesday that the rise in respiratory illnesses in China was a common issue faced by all countries and that Chinese authorities have it under effective control.

China's Taiwan affairs office and authorities in Hong Kong and Macau did not immediately respond to requests for comment. (Reporting by Ben Blanchard in Taipei and Andrew Silver in Shanghai; Additional reporting by Anne Marie Roantree and Farah Master in Hong Kong; Editing by Miral Fahmy)