Medical staff check a patient's condition at a temporary hospital converted from "Wuhan Livingroom" in Wuhan, central China's Hubei Province, Feb. 10, 2020. (Xinhua/Xiong Qi)

Central China's Hubei Province, the epicenter of the novel coronavirus pneumonia (COVID-19) outbreak, recorded a sharp increase in the number of both newly confirmed cases and deaths on Wednesday after the number of clinically diagnosed cases was included in the total.

Experts believed the sharp increase in deaths may have resulted from the adjustment of diagnostic criteria and the previous accumulation of cases, especially those in critical conditions, but they said that further explanations from the Hubei provincial government are needed.

Wang Peiyu, a public health professor at Peking University, told the Global Times on Thursday that including the number of clinically diagnosed cases in the total of the newly confirmed cases means that Hubei has adjusted the diagnosis criteria, turning some cases previously deemed as suspected ones into confirmed cases, which would also lead to the surge in the number of deaths.

Hubei previously accumulated a large number of severe cases, and it could also be the case that many of these patients may eventually have not been saved, Wang said.

Wang Guangfa, a respiratory expert at Peking University First Hospital, told the Global Times on Thursday that the increase in the number of confirmed cases and deaths in Hubei could also be caused by problems in the technical aspects of clinical diagnosis, as some doctors may not have fully understood the clinical diagnosis criteria and only relied on CT scans.

Meanwhile, the experience and skill level of the doctors could also have affected the interpretation of CT scans, as only experienced doctors can make a general prediction about the etiology of pneumonia through a CT scan combined with clinical manifestations, Wang Guangfa said.

All this may have resulted in doctors treating pneumonia caused by other pathogens as newly clinically diagnosed cases of novel coronavirus pneumonia, Wang Guangfa said.

Wang Guangfa called for strengthened training for doctors on diagnostic criteria and accurate CT scan analysis. Meanwhile, the nucleic acid test remains the most important method of diagnosis, so training in sampling technology, laboratory testing technology and quality supervision of testing kits should be strengthened.

Yang Zhanqiu, director of the pathogen biology department at Wuhan University, told the Global Times on Thursday that the increase in the number of deaths also showed that there are no drugs that can cure the disease, and previously admitted patients were critically ill with no effective treatment.