The scenic demarcation line of the Bohai Sea and Yellow Sea in Dalian, Northeast China's Liaoning Province Photo: VCG

Cases of hepatitis A found in North East China's Liaoning Province have caused public concern over a potential outbreak. A local health authority said on Saturday that cases of the disease were only sporadic in the region, but it did not reveal the number of cases.

"Rumors about people getting hepatitis A from eating undercooked seafood have been going around the city for 10 days," Zhao Dafu, a resident in the coastal city of Dandong, Liaoning Province, told the Global Times on Monday, adding that it has exacerbated public anxiety amid the current COVID-19 outbreak. 

Dalian, another coastal city in Liaoning, has also been at the center of disease outbreak rumors. Ma Wenchun, a resident in Zhuanghe, a county-level city administered by Dalian, told the Global Times on Monday that she saw a widely shared message in a WeChat group on February 27, saying that five out of 12 people tested positive in a liver function test in a local hospital, which implied that hepatitis A was prevalent in Zhuanghe.

The Center for Disease Control (CDC) of Zhuanghe released a notification on its WeChat official account on February 28 in response, without directly confirming whether the message was true or false. 

The notification said that cases of hepatitis A found in Zhuanghe were only sporadic, not clustered, and that increasing cases are just in line with the seasonal epidemic trend of hepatitis A. A health center in Dandong also claimed that the disease is controllable even though the number of cases has been slightly increasing. 

However, the statements did not calm down the public concern. A photo of a pharmaceutical company's announcement in another city in Liaoning Province spread over social media, in which the company warned its employees on Friday to not eat seafood due to the hepatitis A outbreak in Dalian and Dandong. 

The photo caused doubts among some netizens about the credibility of the local health authorities because the exact number of the hepatitis A cases in the region has not been revealed to the public. 

"How can we believe that this is not an outbreak if we don't know how many people have already been infected with the disease?" wrote a netizen on Sina Weibo, expressing worries that it might become another outbreak at this difficult time. 

The CDC in Dalian stressed again that cases of hepatitis A in the city were just sporadic in an interview with the National Business Daily on Saturday, and said that they will sound an alarm if the disease becomes more prevalent. 

Residents were also advised to fully cook seafood before eating it to prevent the possible infection with hepatitis A. 

People may get infected by eating uncooked and contaminated seafood as shellfish are the primary vectors of hepatitis A and the virus can survive in them for more than three months, Zhao Guoqing, chief physician of liver disease at Beijing You'an Hospital, told Jiankang Shibao, a health-focused newspaper under People's Daily, on Sunday.

Hepatitis A spreads mainly from fecal-mouth transmission and patients mostly show alimentary canal symptoms, such as nausea, Zhao said, noting that generally patients' liver function will return to normal after treatment for about one month.