Lin Xiaoxiao also immediately understood Li Bai's intentions.

Don't tell her the answer directly, but tell her the idea of solving the problem, which is also the quality that the on-site investigators need to have.

Li Bai's mobile phone rang.

When the caller ID came, Yang was the chief of the Municipal Disease Control and Inspection Department.

"Director Li, the results of the first two patient specimens sent have come out, and the fluorescent PCR method has detected Rickettsia Moschi, which is determined to be endemic typhus, and the nucleic acid testing of the second batch of sent specimens is underway. ”

At the same time, Yang Le, who was in Lianyun District Hospital, also sent over the list of the second batch of patients suspected of endemic typhus and detailed investigation information.

The second group of patients were all residents of urban villages, including original villagers of Xingfu Sixth Village and temporary tenants.

One of the women, surnamed Li, lives next door to the Chan Kee grocery store, and the other patients are also scattered around the Tan Kee grocery store.

"I've got a new list of patients and patient addresses here, and I'll go to those addresses after I've placed the sticky mouse boards here. ”

Soon, everyone in the CDC team received a new list of patients and addresses on their phones.

Yang Yufeng looked at the address and sighed: The on-site flow is really a physical job.

Lin Xiaoxiao: "Indeed, it seems that we can't finish it today, and it is estimated that we may have to carry out a large-scale rodent eradication operation in urban villages starting tomorrow." ”

Next door to Chen Kee's grocery store, Aunt Li's home.

Aunt Li's house is also a two-story small building, the first floor is rented to temporary tenants, and the second floor is where Aunt Li's old couple live.

Renting on the first floor are a couple of young girls who work in the office building next door.

Seeing that the people from the disease control came to investigate, the young girl took the initiative to report the situation.

"The environment in the urban village is very poor, we rent a house here because the rent is cheap, and after renting, we can barely live in it by renovating it ourselves, and there are often rats. ”

Another girl: "A few days ago, a big mouse ran out of the breakfast stall of the Chen Ji grocery store next door, anyway, I don't dare to eat the things sold near here, I go to the breakfast shop downstairs of the company." ”

Li Bai asked, "Have there been any rats in the house?" Have you ever been bitten by insects?"

"Nope. The two girls shook their heads at the same time, "There has been a wave of disease control workers just now, asked this question, we put a rat guard at the door, and the corners of the walls were also re-plastered with cement during decoration, at least the two of us have a clean house, we don't have a bag bitten by insects, we don't have a fever, we don't feel uncomfortable, and we don't get sick." ”

"How much do you know about Aunt Li's situation upstairs?" asked Li Bai.

"I don't know much, although she is our landlord, she usually just meets and nods and greets, and everyone lives their own lives. However, I often see them chilling out on the rooftop in the evening. ”

Another girl added, "I've been to the second floor a few times, and although the overall environment of the urban village is poor, Aunt Li's house is very clean, and she has a cat, so there should be no mice." ”

From the 1st floor to the 2nd floor, I arrived at the place where Aunt Li lived.

Sure enough, as the young girl said, Aunt Li's house was very clean.

A big tanuki was crouching in the doorway basking in the sun.

Cats eat mice, and if the eaten rat has fleas on it, then it is likely to run to the cat.

"Catch the cat!" Li Bai whispered.

Zhang Lin was about to make a move, but Lin Xiaoxiao had already lassoed the tanuki with a large sampling bag.

Yang Yufeng was so frightened that she took two steps back, thinking to herself, this Lin Xiaoxiao is really the same as the rumors, no one is afraid of the dead, let alone mice and cats, it is really tough!

"Do you want to bring the cat back?" Lin Xiaoxiao asked.

"No, check it for fleas. ”

How to check if there are fleas on a cat? Lin Xiaoxiao didn't know.

In fact, she also didn't know how to test rats for fleas.

Li Bai took out a fine-toothed comb from the sampling box, combed it backwards along the fur of the big cat, and after combing it a few times, a flea figure appeared on the comb.

After a few combs, 5 fleas have been collected, all of which have been packed into small sampling bags.

Lin Xiaoxiao helped hold the sampling bag on the side, and after Li Bai said that the sampling was completed, he immediately sealed the mouth of the sampling bag.

Yang Yufeng's scalp was numb, and she wouldn't let her comb the mouse after she went back later, right?

One of the intern boys asked, "Director Li, the patient in this family should have been bitten by fleas on the cat, so he was infected, right?"

Yang Yufeng pursed her lips and thought to herself, don't show off in front of the leader, this is something you know at a glance, do you still need to ask?

Li Bai didn't answer the rhetorical question, "It's still the question just now, what are the transmission routes of endemic macules in Shanghai?"

The boy was stunned when asked, didn't Lin Xiaoxiao already answer just now?

In addition to rat-flea bites, it is also possible to eat contaminated food or have wounds that come into contact with the contaminated environment, but the latter two are less likely.

Li Bai asked again: "Uncle Li and Aunt Li usually live together, only Aunt Li is sick, but Uncle Li is not, how can this reason be explained?"

"Fleas don't bite Uncle Li?" the boy whispered, feeling that this reason was untenable.

Lin Xiaoxiao tried to analyze, "The diet is different, the on-site flow data sent from Lianyun District Hospital just now shows that although Uncle Li and Aunt Li live together, Aunt Li has a special habit, she likes to eat egg cakes from Chen Ji Grocery Store in the morning, and Uncle Li likes to eat soybean milk fritters on the street, which is the difference between the two." ”

Another intern boy reacted, "There's a problem with breakfast at the Chen Kee grocery store, no wonder you picked samples at the breakfast stall for a long time." ”

Li Bai: "The specific transmission route will not be clear until the sample is brought back to the laboratory for testing." ”

There are a total of 8 patients in the second batch of lists, which are basically distributed in the urban village area with a radius of 2 kilometers centered on the Chen Kee grocery store.

After investigating Chen Kee's grocery store and the homes of 8 people, it was already evening.

Yang has already called, and the test results of the second batch of patients have come out, confirming that it is endemic typhus caused by Rickettsia Moesi .

Except for the sticky mouse board, which was collected on the second day, other environmental specimens were collected.

Back at the Municipal Center for Disease Control and Prevention, Li Bai and Zhang Lin handed over samples to the laboratory department.

After the handover, Li Bai asked the four interns to go back, the day's work was temporarily over, and he came to work on time at 8:30 in the morning on the second day.

At the same time, the work to be done on the second day was briefly explained, because today it is only to sample the external environment of the patient's home, and tomorrow it is necessary to collect the sticky rat board, and at the same time, it is necessary to carry out the rodent extermination work in the entire urban village, which is a lot of work.

Yang Yufeng breathed a sigh of relief for the time being, the first day of the internship was finally over, it was thrilling and dangerous, and she wanted to go back and get a good night's sleep.

A few interns discussed taking the bus back to school together, and Lin Xiaoxiao: "I also want to see how the lab catches fleas for mice." ”

"Oh my God!" Yang Yufeng stared at Lin Xiaoxiao in disbelief, "Are you sure you want to stay...... Studying?"

"Well, I've checked, there hasn't been an endemic typhus case in Yunhai City for many years, and the opportunity is rare, do you want to stay and study together?"

Yang Yufeng shook his head, "No, no, no, I have to catch mice in the urban village tomorrow, I have to save some strength, otherwise I will really faint." ”

Intern Xiao Wang: "I heard that the CDC often works overtime until the night at night. ”

Intern Xiao Zhang: "Little relatives live around here, we can't do it, it takes more than an hour to take the bus back to school." ”

Yang Yufeng: "And there are other students in the laboratory who are rotating, and the department we are rotating now is the emergency office, so you may not be able to go even if you want to." ”

The two intern boys didn't plan to stay after discussing it, after all, they didn't want to stay in the disease control work, so they didn't have to behave like this, and they didn't have to work so hard.

After the three of them left, Lin Xiaoxiao found Li Bai to explain the situation.