"It's a mulberry caterpillar."

Gu Yanan opened the sampling box and took out the sampling bag, which contained a few leaves and a few mulberry caterpillars on it.

Gu Yanan handed the pupa dug out of the soil to Section Chief Li, "This is the pupa of the poisonous caterpillar, hatch it in the incubator, and identify the subtype according to the shape of the moth." ”

"No problem."

Lu Li had already put the poisonous caterpillar that Gu Yanan brought back under a microscope to observe, and after comparison, it was found that the short thorn found in the dust of the classroom of Binhai Road Primary School was the poisonous hair on the poisonous caterpillar.

Think back to his experience in the Crescent Bay Wetland Park, when he crawled out of the mud in the lake, took off his protective suit, and exposed his bare arms directly under the trees. It is inevitable that there are also poisonous caterpillars on the trees, and I should have been exposed to the poisonous hairs of this poisonous caterpillar at that time, so that I would have unbearable symptoms of itching.

But all of this is speculation, and it will take further experiments to determine that the symptoms are caused by this poisonous caterpillar.

Lu Li volunteered, "Sister Yanan, I came to do the patch experiment, and put the poisonous hairs of these poisonous caterpillars on my arm, if there are symptoms, it means that this poisonous caterpillar caused this dermatitis epidemic." ”

Xiao Chu also volunteered, "I'm also here to volunteer." ”

Gu Yanan shook his head, "I don't need you two, just let me volunteer." And we can't use the poisonous hairs of the poisonous caterpillars that we collect under the banyan tree, but the dust collected in the classroom, which is telling. ”

Xiao Chu echoed, "Yes, Sister Yanan is right, to imitate the contact environment, many patients are not directly exposed to poisonous caterpillars, but to dust, so using dust to do patch experiments is the most illustrative." ”

Gu Yanan began to cover the skin on the curved side of his forearm with pieces of dust-stained paper collected from the classroom, preparing to do a patch experiment, Xiao Chu also stretched out his arm, "I also want to be a volunteer, so that two volunteers can already explain the problem." Brother Lu Li, forget it, he had just had a disease before, and although his symptoms have been alleviated now, he is not suitable for volunteers who do this experiment. ”

Lu Li still wanted to fight for another chance, "Test the poison yourself, how can I miss such a rare opportunity?" ”

Xiao Chu pushed Lu Li away with a smile, "Since it's a good opportunity, you have to leave it to me, a newcomer, don't rob me." Besides, I also want to experience what it was like for Lu Li to be in the wetland park. ”

Gu Yanan agreed to Xiao Chu to join, and with the assistance of Section Chief Li and Lu Li, he also put dust patches on Xiao Chu.

Soon, both of them felt an unbearable itch in the patch.

Xiao Chu grinned, Gu Yanan also frowned, and the others knew that the patch experiment was starting to work when they looked at the two of them.

"What does it feel like? Do you want to take the patches off? Lu Li asked these two people.

Xiao Chu hurriedly put his arm in front of Lu Li, "Hurry up, hurry up, take off the patch, I can't stand it, it's painful and itchy." ”

Lu Li took off the patches for the two of them, and found that the skin of the two people had begun to appear red spots.

Xiao Chu couldn't help but scratch the red dot with his hand, and blisters began to appear in the center of the red dot.

"Pimples have appeared!" Lu Li exclaimed, "The symptoms are exactly the same as when I was in the Crescent Bay Wetland Park, and this dust is indeed the source of the symptoms of the teachers and students of Binhai Road Primary School. ”

The same pimples also appeared on Gu Yanan's arms, Xiao Chu didn't care about the stinging pain on his arms, so he took the ointment from Lu Li, and applied it to Gu Yanan's arm first, and then applied the ointment to his arm.

Lu Li saw all this in his eyes, seemed to have an understanding, and said to Xiao Chu with a smile, "Now you know how I felt at the time, it was too uncomfortable." ”

"Well, that's empathy. There must be poisonous caterpillars in the woods of the Crescent Bay Wetland Park, and it is speculated that there may also be poisonous caterpillars in the trees in the green belt of the city, which is why so many people are injured by the poisonous hairs of the poisonous caterpillars. ”

Xiao Chu said as he turned his head to look at Gu Yanan and asked, "Sister Yanan, what should we do next?" ”

Gu Yanan thought about the next steps of epidemic prevention, and suddenly the mobile phone rang, and the caller ID was Wang Xiaoxiao.

Connected to the mobile phone, Wang Xiaoxiao's voice came, "Sister Yanan, the information you asked me to check on the epidemic system has been checked, at present, there are more than 30,000 cases of patients with similar dermatitis symptoms reported in Lianhai City, I have a general analysis of the patient's place of residence, the patient mainly lives in the coastal area and the development zone, and there are cases in other counties, but there are relatively few." ”

"Okay, you make a map of the patient's residence first, and I'll use it when I get back to the office later."

After hanging up the phone, the few people in the laboratory all looked at Gu Yanan and asked.

Xiao Chu was the first to ask, "Sister Xiaoxiao, there's news over there?" ”

"Well, at present, the cases of dermatitis symptoms in the city have been basically sorted out, and I am asking Xiaoxiao to make a map of the distribution of residences to facilitate the formulation of next prevention and control measures."

Several members of the emergency team came out of the laboratory, and Gu Yanan called his brother Gu Jiashu first, "Brother, after our experiments, we found that the culprit who caused the large-scale outbreak of dermatitis in Lianhai City was a poisonous caterpillar.

The patient has caterpillar dermatitis, which is a molting product of these poisonous caterpillars and lysates of dead worms that can invade human skin and cause an inflammatory response.

My advice is to use tape to stick out the poisonous hairs in the affected area before treating the patient, which will be more effective. ”

Gu Jiashu on the other end of the phone agreed, and asked Gu Yanan a few more things about the poisonous caterpillar epidemic, Gu Yanan only said a rough idea, and there were some things she had to go back to the emergency office to read the information and make detailed inferences.

——

Lianhai Center for Disease Control and Prevention, Emergency Office.

Gu Yanan got the distribution map of the patient's residence and frequent activities compiled by Wang Xiaoxiao.

According to the distribution map, Gu Yanan drew several key areas and sent them to each county CDC, asking them to go to the key areas in the distribution map to check whether there were poisonous caterpillars in the local green belt forests.

The news quickly came back that there were indeed poisonous caterpillars in these areas.

Gu Yanan also handed over the distribution map to the greening team of the Municipal Garden Bureau, and after negotiation, they were put in charge of spraying and pesticide control in these places.

At the same time, Gu Yanan posted an announcement on the epidemic of poisonous caterpillars on the disease control website, suggesting that everyone wear long pants and long sleeves, wear masks and hats when traveling outside, and try to avoid bare skin to prevent being stimulated by the poisonous hairs of poisonous caterpillars.

Two days later, after spraying pesticides to control insects and people taking the initiative to protect themselves when they go out, the cases of dermatitis caused by poisonous caterpillars decreased significantly.

Section Chief Li of the laboratory reported to Gu Yanan the hatching results of insect pupae found under the four small-leaved banyan trees in Binhai Road Primary School.

After cultivating butterflies, the pupa was identified as the lone star yellow poison moth of the insect class Lepidoptera.

The caterpillars on the ficus microphylla tree are the larvae of the Lone Star Yellow Moth.