A child takes the nucleic acid test at a testing post set up at a primary school in Dongxihu District in Wuhan, central China's Hubei Province, May 15, 2020. Wuhan will arrange nucleic acid tests for all residents who have not been tested before, in order to better know the number of asymptomatic cases of the novel coronavirus. The decision was made as the virus-ravaged city continued to report daily increases of asymptomatic infections, which raised concerns among the public. (Xinhua/Xiao Yijiu)

An expert from the National Health Commission (NHC) said that the confirmed COVID-19 cases in Northeast China's Heilongjiang and Jilin provinces have different characteristics from those in Hubei Province. 

Qiu Haibo, an expert from the medical treatment group under the NHC, said on Tuesday on a TV program on China Central Television that based on the gene sequencing, most of the cases in Jilin and Heilongjiang were completely consistent with the imported cases, but not quite the same as those found in Hubei.

According to Qiu, the cases in Heilongjiang and Jilin provinces have a long incubation period, and their clinical symptoms are not typical. In many cases, the patients do not have fever, but do suffer from fatigue or sore throat. Some patients have no symptoms, resulting in family clusters.

Qiu noted that Wuhan's patients suffered not only lung damage, but also myocardial, renal and intestinal damage. However, the cases in Northeast China which are related to imported cases mainly showed lung damage, with very slight damage to the heart, kidney or intestines. 

He also noted that the cases in Northeast China have a longer period for carrying the coronavirus. Nucleic acid tests on Wuhan patients usually came back negative within a week or at most two weeks after the patient showing symptoms. However, this time period was longer for patients in Heilongjiang and Jilin provinces.

However, the curative effect is better in Northeast China provinces, said Qiu, and the proportion of severe cases in Heilongjiang and Jilin is lower than that in Wuhan. 

The local government in Northeast China's Shulan, which comes under the administration of Jilin city in Jilin Province, announced on Tuesday that all local residents who have returned from Russia this year must register their personal information with residential communities and undergo free nucleic acid testing. 

Jilin city, currently the center of a new outbreak, reported four domestically transmitted COVID-19 cases on Tuesday, bringing the total number of domestic cases in Jilin Province to 133, with 25 cases remaining under treatment in Jilin city.