A global coronavirus pandemic could end by June if countries mobilize to fight it, a senior Chinese medical adviser said on Thursday.

About two-thirds of global cases of coronavirus have been recorded in China’s central Hubei province, where the virus first appeared in December. But in recent weeks the vast majority of new cases have been outside China, Reuters reported. 

The Chinese authorities believe that they took strict measures, including almost completely shutting down Hubei, prevented major outbreaks in other cities and said that other countries should learn from their efforts.

“Broadly speaking, the peak of the epidemic has passed for China,” said Mi Feng, a spokesman for the National Health Commission. “The increase of new cases is falling.”

Zhong Nanshan, the Chinese government’s senior medical adviser, said that as long as countries take the outbreak seriously and are ready to take firm action, it could be over worldwide in a matter of months.

Zhong, an 83-year-old epidemiologist renowned for helping combat the SARS outbreak in 2003, said viruses usually become less active during the warmer months, which can help slow down the spread. “My estimate of June is based on scenarios that all countries take positive measures. But if some countries do not treat the infectiousness and harmfulness seriously, and intervene strongly, it would last longer.”