Close contacts of tourists in quarantine

Shanghai has tracked and quarantined 14 people who have closely contacted four tourists who who showed positive results for coronavirus infection in nucleic acid test earlier this week.

One of the four was confirmed with the coronavirus and sent to a designated hospital for treatment, the city's health commission said.

The man is a Qinghai Province native who is studying in Iran. He left Tehran and arrived at the Pudong International Airport on Monday via Bangkok, and was sent for quarantine at a designated facility after entering Shanghai and transferred to a hospital on Tuesday.

“The person was confirmed as a coronavirus case based on lab tests, imaging check, clinical symptoms and epidemiological investigation," said Zheng Jin, a spokeswoman of Shanghai Health Commission.

So far the other three haven't show any symptoms but will be kept in quarantine and their health monitored. 

The man is also the only new confirmed case reported in the city as of midday Thursday.

Meanwhile, eight suspected cases have been ruled out and five local patients were discharged upon recovery in the latest 12-hour period.

The city has reported 339 infections and ruled out 2,464 suspected cases.

Among all confirmed patients, aged between 7 months and 88 years old, 145 have traveled or lived in Hubei Province, 34 have traveled or lived in other regions, 158 had contact history with infected persons, one has lived in Iran and one case is still under investigation.

A total of 111 patients are from outside the city, one from overseas, while 227 are local residents, referring to those with registered residency and people staying in the city for over six months.

According to the local health commission, 24 patients are stable, one is serious and eight are critical. A total of 303 patients have recovered and been discharged from hospital.

There have been three local fatalities so far.

Another 34 suspected cases are under investigation, the commission said.

Fu Chen, director of the Shanghai Center for Disease Control and Prevention, said it was enhancing epidemiological investigations in order to control spread of the virus.

By Wednesday, they had launched investigations into 2,850 cases and assisted other provinces and cities to investigate 422 cases. More than 10,700 close contacts are in quarantine for medical observation.

"Epidemiological investigations are an important method to prevent the epidemic’s spread and expansion. It mainly concerns the person's exposure, contacts with others, movements and medical condition," said Fu. "It aims to find out the source and way of infection, and keep people with close contact of the person in quarantine."

He described the investigations as a way to put out the "spotty sparkles" of epidemic and cut the route of its spread.

"There are three key points that should be paid attention to for epidemiological investigations. First the investigators should try their best to get clear on everything and everyone related to the person's acts. But it's really challenging to have the person clearly tell each part of his or her daily schedule in the past two weeks before showing symptoms," Fu said.

"Then it's also difficult to find the origin of infection if the person went to many different areas and participated in several events. Thirdly, sometimes the person's refusal to give required information and even concealing important parts will make the work hard."

To solve these problems, Fu and his colleagues often use special dates like holidays, people and events to help remind people of where they had been. 

He cited two examples in which investigations played an important role. 

"In mid February, there was a patient at Yueyang Hospital who concealed his information and caused medics to be kept in quarantine as his close contacts. In that case, they used the investigation to trace the patient's movements and close contacts."

In another case, on February 26, the center received a request for assistance with a confirmed case of a person traveling from Iran to the Ningxia Hui Autonomous Region via Shanghai. Its investigation found 63 close contacts within a day.

Meanwhile, the center is also doing lab tests throughout the day. By Wednesday, it had completed 6,610 lab tests on 10,852 samples to confirm or rule out suspected cases.