Connecting the mobile phone, Gu Yanan asked: "Captain Nan, Lu Li and I just returned to the office not long ago, you called me, is there something wrong with the case?" ”

Nan Hanfei on the other end of the phone, "I have something to ask you for help."

Just now, the forensic doctor sent me a report that a type of mycobacterium was detected in the body of the deceased Zhang Zixin, and the scar on the skin of the corpse was suspected to be Mycobacterium leprae.

Your CDC is an expert in infectious diseases, and I want you to confirm it and find some information about leprosy patients, which is very important for case clues, be fast! May I? ”

"No problem, send the test specimens over, and send me a photo of the scar on the skin of the corpse to my email, and I will analyze it."

After hanging up the phone, Gu Yanan canceled his plan to go home, put his suitcase in a corner of the office, and opened his email, ready to see if the external manifestations on the body parts were symptoms of leprosy.

Lu Li heard Gu Yanan mention Captain Nan on the phone, and immediately came to Gu Yanan's side and asked, "Is it about the case?" ”

"Well, the police station will send a few specimens in a while, and we need to do a confirmatory test for leprosy bacilli."

"I'll do it!" Lu Li volunteered to do something to solve the case.

Gu Yanan didn't doubt Lu Li's detection skills, but expressed concern about Lu Li's personal feelings, "This is a specimen of the Pink Fairy, is it okay for you to do it yourself?" ”

"Director Gu, don't worry, I will separate my personal feelings from work."

——

Lianhai CDC, Laboratory.

Lu Li took the specimens sent by the police station and did experiments in the laboratory within the experiment.

In order to produce results quickly, Lu Li first used a PCR kit for leprosy to perform quantitative fluorescence detection, and the results of this experiment can be obtained within two hours at the earliest.

After the PCR sample was put on the machine, while the machine was running, Lu Li did two more auxiliary experiments - the leprosin experiment and the specimen smear microscope.

The leprosin test has cross-reactivity with the tuberculin test, and the accuracy of the results is low, so it can only be used as an auxiliary experiment.

As for the specimen smear, microscopic examination is the most primitive examination method, but it is also the most intuitive, and the bacteria can be seen directly.

Positive leprosin test.

After staining of the specimen smear, mycobacteria are observed under the microscope.

Soon the results of the real-time PCR were also out, and the leprosy bacillus was positive.

The pink fairy Zhang Zixin was a leprosy patient before she died!

Lu Li took the test results, hurriedly ran back to the emergency office, and handed the results to Gu Yanan.

Gu Yanan frowned slightly, "There have been no new cases of leprosy in Lianhai City for six consecutive years, where did Zhang Zixin get infected with Mycobacterium leprae?" ”

Lu Li diverged his thoughts and began to speculate, "She may have been in contact with lepers before, and it is possible that she was accidentally infected." ”

Gu Yanan: "The leprosy patients in our city are concentrated in a few leprosy treatment sites, and after years of evolution, those treatment sites have become villages where leprosy patients gather and live. ”

Lu Li: "When I chatted with Pink Fairy on the Internet before, she said that she likes to be a volunteer and has participated in volunteer activities, such as going to a nursing home, but she didn't say that she has never been to a leprosy village, so she has to go back and ask her parents or friends to find out." ”

Gu Yanan entered the epidemic network, checked the relevant information of leprosy, and found that among the existing leprosy patients in Lianhai City, Zhang Zixin's name was not known.

Zhang Zixin is indeed the first new case of leprosy in Lianhai City in the past decade.

Looking at the test results, Gu Yanan's fingers unconsciously knocked on the desk, and finally said: "Leprosy is one of the diseases routinely monitored by our CDC, the incidence of leprosy is low, but it is contagious, although Zhang Zixin has died, but people who have been in contact with her may be infected, and she is the first new case of leprosy in Lianhai City in the past six years, we must do a flow investigation to prevent the possibility of further spread of leprosy, which is also a clue to the police to solve the case." ”

Gu Yanan shared the test results from the CDC laboratory with Nan Hanfei.

If the CDC wants to conduct an epidemiological investigation, it is necessary to find out the living environment and life trajectory of the pink fairy Zhang Zixin before her death.

——

The home of the Pink Fairy Zhang Zixin.

According to Zhang Zixin's identity information, Gu Yanan found Zhang Zixin's home in Xicheng District, Lianhai City.

The community where Zhang Zixin lived before his death was a residential area called "Xinghai Garden" near the coast in Xicheng District.

Zhang Zixin's home is located on the 21st floor of a 33-storey building in Xinghai Garden Community.

Gu Yanan took Lu Li, Gao Fei and Wang Xiaoxiao to drive the on-site epidemiological investigation vehicle of the CDC to the Xinghai Garden Community and found the 21st floor where Zhang Zixin was.

Gu Yanan knocked on the door.

The door was opened by a woman in her fifties with a haggard face.

"Is this Zhang Zixin's home?" Gu Yanan asked.

The woman standing behind the door looked at Gu Yanan through the half-open door, and the group of people behind Gu Yanan, and asked, "What are you doing?" ”

Gu Yanan showed his ID and introduced himself, "We are the staff of the Lianhai City Center for Disease Control and Prevention, because we determined that Zhang Zixin was infected with leprosy before his death, so we came here for epidemiological investigation. ”

The woman opened the door wide, "Come in." ”

Gu Yanan walked into the living room and was greeted by Nan Hanfei and two young policemen.

Nan Hanfei: "We are here to investigate the clues of Zhang Zixin's case. ”

Gu Yanan: "We are here to conduct an epidemiological investigation on leprosy. ”

Zhang Zixin is an only daughter who lived in this house with her parents before her death.

Zhang Zixin's father, a man in his 50s, was sitting on a sofa in the living room at this time, being questioned by the police.

The police officers and CDC staff were standing in the living room, which was once quite spacious.

Nan Hanfei took the initiative to say to Gu Yanan, "We've already asked about it here, so let's ask from the CDC, do you mind if we listen on the side?" ”

Gu Yanan knew that Nan Hanfei wanted to learn some clues about the case that they had not yet mastered from their questioning.

"Don't mind."

Nan Hanfei motioned to the two policemen to stand up with his eyes and gave up the position of the sofa to Gu Yanan.

Gu Yanan shook his hand directly, "No, I'll just stand." ”

Nan Hanfei looked carefully at Gu Yanan and several CDC staff behind her, all of whom were wearing gloves.

Nan Hanfei understood that the people from the CDC were here to conduct an epidemiological investigation, and they must have thought that this room was full of germs, and they wore gloves on their hands, and they would not touch the things in the room at will, let alone sit down.

Nan Hanfei subconsciously rubbed his hands and stood beside Gu Yanan.