Lianhai Center for Disease Control and Prevention, Emergency Office.

Gu Yanan is compiling information from hospitals and schools.

The mobile phone rang, and the caller ID was Gu Jiashu.

"Little sister, the results of the laboratory department of our hospital came out, it was not leprosy, nor tuberculosis, and Mycobacterium avium was detected in the patient's body."

"Mycobacterium avium?!"

"Yes, mycobacterium avium disease is a zoonotic disease caused by infection with mycobacterium avium-intracellular complex, humans can have a variety of tissue and organ damage after being infected, such as lungs, bone marrow and lymph nodes, in the early stage of infection, the patient's symptoms will be similar to leprosy and tuberculosis, there is no laboratory diagnosis, it is easy to be confused, now the pathogen is determined, and the symptoms of the patients are completely consistent."

Gu Yanan still has doubts, "Mycobacterium avium disease is a zoonotic disease, this bacterium is the pathogen of domestic animals such as birds and pigs, although it can infect people, but it is an opportunistic pathogenic bacteria, generally only infecting people with weak immunity, Mr. Wang and the students are usually in good health, no underlying diseases, how can they be infected by this bacterium?" ”

Gu Jiashu: "I have never been in contact with patients with mycobacterial disease in avium before, and this is the first time I have been treated, and I have never been in contact with a cluster of cases of this disease. ”

"Brother, you haven't seen it, I haven't seen it, and there is no record in the relevant literature, this is the first time that Mycobacterium avium cases have erupted."

Gu Jiashu: "I will treat patients according to the treatment plan for mycobacterium avium disease, but this is a long-term process, more troublesome than treating tuberculosis, as for how the patients are infected is your disease control business, I don't want the hospital to continue to receive similar cases." ”

"Well, we are responsible for the investigation of the epidemic, and I will find the source of infection as soon as possible."

After hanging up the phone, Gu Yanan rechecked the flow survey data.

Teacher Wang, the homeroom teacher of the second class of junior high school, and students Wang Lei, Li Ming, and Zhou Le, all have symptoms of mycobacterium avium disease, and they have been exposed to the same source of infection? Or is it that someone was exposed to the source of infection first, and someone else was re-infected?

In either case, the environment where teachers and students have the most contact is the school.

——

Dongcheng District, Lianhai City, Binhai Middle School.

Gu Yanan led the disease control emergency team to sample the environment inside and outside Binhai Middle School.

Mycobacterium avium can survive in many different ecological environments, soil, air, water, animals, ......

The CDC emergency response team took samples of the school's playgrounds, offices, classrooms, drinking fountains, cafeterias, and green belts inside and outside the school, all where Mycobacterium avium might be present.

Members of the emergency response team, wearing protective suits and carrying sampling boxes, were scattered around the school.

White hazmat clothing is very conspicuous on campus.

Because the causative agent of the epidemic was identified, the CDC released the epidemic news in a timely manner, and the rumors about leprosy on the Internet gradually subsided with the assistance of the Internet police, and the students who left the school were sent back to school by their parents one after another.

Gao Fei and Wang Xiaoxiao were collecting water samples in the central fountain pool at the school's main entrance, when a petite female student returned to school accompanied by her parents.

When the parents saw the flow of the disease control site parked at the school gate, and saw the disease control personnel wearing white protective clothing, they immediately hid far away, and whispered to remind their children, "See, stay away from the people wearing these clothes, there are infectious diseases, you are our family for three generations, a single seedling, don't get any disease." ”

Although the parent's voice was small, it still drifted into the ears of Gao Fei and Wang Xiaoxiao.

Wang Xiaoxiao took the collected water sample, looking helpless, "I was discriminated against again, who is not a baby, I am also the third generation of our family." ”

Gao Fei comforted Wang Xiaoxiao, "The parents are not malicious, we are dressed like this, which does mean that there may be a source of infection nearby, but the source of infection is not us, but the nearby environment." ”

Gu Yanan had already finished collecting samples, and when he came back, he heard the conversation between the two and comforted: "The protective clothing we wear not only protects us from being infected, but also serves as a warning to onlookers. ”

——

Lianhai Center for Disease Control and Prevention, Emergency Office.

The results of the environmental samples collected from Binhai Middle School have come out.

Mycobacterium avium was not detected in any specimens.

The source of the outbreak is not on campus.

So where will the source of infection be?

Gu Yanan stared at the flow information and frowned, there must be something missing.

Frowning and thinking, his brother Gu Jiashu called.

"Little sister, Teacher Wang has just been admitted to the ICU."

"What?" Gu Yanan asked in surprise, "How could it get serious?" The pathogen has been found, and it should get better according to the protocol, why did it go to the ICU? ”

"Our infectious disease department is in accordance with the treatment plan of Mycobacterium avium, but the patient's fever has not subsided, the infection has not been controlled, I don't know if it is because of the patient's constitution, or the pathogen this time is different from before."

"Have you done the antimicrobial susceptibility test?"

"The hospital laboratory department is doing it, but it will take some time to isolate pure Mycobacterium avium."

"Oh, our CDC laboratory has isolated pure Mycobacterium avium from patient specimens, and I asked them to continue the antimicrobial susceptibility test and notify you of the results. Brother, that's what you're calling me for today? ”

"No, there is more important news, our hospital has received two more Mycobacterium avium patients."

"Students at Marina Middle School? Or a teacher? Gu Yanan was shocked, could it be that the epidemic began to spread?

"It has nothing to do with Binhai Middle School, a man and a woman, both in their twenties, a couple, the two are in the same company, usually live together, live in Xicheng District, Lianhai City, and work in Xicheng District, I asked them some simple information, and they all said that they have never been to Binhai Middle School, and they have never been in contact with the teachers and students of Binhai Middle School."

Gu Yanan felt that his brother Gu Jiashu had provided an important piece of news, two people were infected with Mycobacterium avium at the same time, and if it really had nothing to do with the epidemic in Binhai Middle School, then it was another cluster case outbreak.

"Brother, I know, I'll go to the hospital immediately now and see a new patient."

"There's no hurry, and the patient won't run."

——

Lianhai First People's Hospital, Department of Infectious Diseases.

The newly admitted Mycobacterium avium patient is a couple who are staying in the infectious diseases ward.

Gu Yanan showed his work card and asked about the epidemiological history of the two.

The two are ordinary office workers, who have just joined the work and work in a foreign trade company, usually working from 9 to 5 and exercising outdoors on weekends.

The scope of activities of the two has little overlap with that of Marina Middle School.

After doing the preliminary epidemiological history investigation, Gu Yanan left the ward and arranged work in the corridor of the infectious disease department, and the couple cases were handled according to a separate outbreak investigation, and the staff of Xicheng District Disease Control and Prevention were arranged to take samples from the company and apartment where the two lived.

After arranging the work, Gu Yanan inadvertently looked up and saw a familiar figure.