The length of hospital stays and quarantine for COVID-19 patients will be significantly reduced under China's updated COVID-19 treatment protocol, which will help relieve the pressure on medical resources, Shanghai's top coronavirus expert said on Thursday.The average length of stay at local hospitals for COVID-19 patients is expected to decrease from 15 days to 10, according to the new protocol, said Dr Zhang Wenhong, head of Shanghai's COVID-19 treatment team and director of the National Center for Infectious Diseases.The quarantine period after recovery will also be halved to seven days at home rather than two weeks of quarantine and medical observation as previously required.