Doctors check the CT image of a patient's lungs at Leishenshan (Thunder God Mountain) Hospital in Wuhan, capital of central China's Hubei Province, Feb. 9, 2020. (Photo by Gao Xiang/Xinhua)

Nearly a dozen prison and justice department officials in three Chinese provinces have been removed from their posts on Friday, after the prisons reported altogether 447 new cases of COVID-19 infection during the previous day, which experts say revealed the blind zones in the national campaign against the epidemic.

The Central Political and Legal Affairs Commission of the Communist Party of China has formed an investigation team, including officials from Supreme People's Procuratorate, Ministry of Public Security, and Ministry of Justice, to probe the COVID-19 outbreak in the Shandong prison.

On Thursday, Shandong reported 202 new cases including 200 in Rencheng Prison. Zhejiang reported 28 with 27 from Shilifeng Prison. New cases in these two provinces accounted for 89 percent of the total, which analysts said showed the risks of virus transmission through clustering have been exposed in China as prisons with closed spaces and large number of inmates could easily lead to multiple infections.

COVID19 epicenter Hubei Province on Friday revised its Thursday new infection data from 411 to 631, adding 220 new infections in its prisons, local health commission said on Friday noon.

The commission said it received a handwritten report from prison department Thursday night as there is no internet-based data reporting system from the prison system in Hubei. After careful verifications, the commission added those cases into the overall data.

Eight officials involved in Shandong Province, including the Party chief of the Shandong Provincial Department of Justice and Party chief of provincial prison management department were removed from post. Two prison officials in Zhejiang Province have been removed from post, and one police was under investigation. Director of Wuhan Women's Prison was also removed after 230 infection cases were found in the prison. 

An official with a prison in Southwest China who requested anonymity told the Global Times that prisons are vulnerable to epidemics due to inmates clustering in small and closed spaces and weak medical services.

"It's not easy to detect suspected patients and cut off the transmission channels in a timely manner with poor medical facilities in prisons," the official said.

The officials said prisons must prevent the outbreak from the source to lower the risk of importing the virus. Measures such as temporarily suspending goods transportation and using video and other technologies to conduct remote trials should be adopted.

Prisons have to strengthen cooperation with medical institutions outside to make up for the shortage of medical resources and improve quality of medical services, the official said.

In Zhejiang, all confirmed patients in the prison have been sent to hospitals for treatment and no deaths have been reported in the prison, according to Zhejiang's provincial government. The prison has been under lockdown to prevent further spread of the virus.

According to the Beijing News, a police officer surnamed Luo in the prison visited family in Wuhan and was diagnosed with the virus afterwards. 

Rencheng Prison in East China's Shandong Province has reported a total of 207 confirmed patients — seven police officers and 200 prisoners. Among them, 200 were reported on Thursday alone, and the total new confirmed cases in the whole province stood at 202 on Thursday. 

At present, among 200 prisoners who were confirmed to have been infected with the virus, 125 are mild and 75 are normal. There are no severe and critical cases. The diagnosed police officers are also light, normal and all patients have stable vital signs, said Shandong health commission director at press conference on Friday.

At the press conference, Wu Lei, vice Party secretary of Shandong provincial department of justice and director of the Shandong Provincial Prison Authority, said that a police officer on duty at the Rencheng Prison was receiving treatment and quarantined by a hospital after cough on February 12 and was confirmed infected the next day. Another officer in preparation of duty was also confirmed infected the same day.

After the two officers were quarantined, the prison conducted an overall check of all officers, those serving sentences and people who had close contacts with the two officers, according to Wu, adding that lockdown measures were imposed in relevant areas. 

The new cases reported in the prisons raise the alert for the whole country to strengthen protection measures within prisons and other densely populated venues, experts said.