Since there are few common characteristics of patients in the emergency room, the only place where the outbreak is clustered is at Corniche Elementary School, from where you may find clues.

Gu Yanan came out of Zhang Xiaolan's ward and returned to the emergency room, and found that Lu Li's skin with red pimples had been smeared with ointment by the nurse, and the doctor had prescribed medicine, and now the symptoms were significantly reduced.

Gu Yanan told Lu Li, Wang Xiaoxiao and Xiao Chu about what she had just learned, and made the next arrangement.

Lu Li went home to rest.

Wang Xiaoxiao returned to the emergency office, and in the name of disease control and control, he notified the large and small hospitals in Lianhai City to immediately report cases with similar symptoms to the epidemic system, and then looked for recent cases with similar dermatitis symptoms from the epidemic system, and looked at the onset time and distribution of these cases, so as to have a general understanding of the epidemic.

Xiao Chu and her went to Binhai Road Primary School for on-site investigation.

After announcing the arrangement, Wang Xiaoxiao and Xiao Chu had no opinion, and Lu Li objected.

"Sister Yanan, I'm already well, I was uncomfortable when I was in the wetland park just now, and now I have to rub some ointment to ease it significantly, I don't have to go home to rest, I want to go to the scene with you to do a flow adjustment."

"I heard from the doctor that direct sunlight like yours can aggravate the symptoms, and if you don't want to go home to rest, you don't have to go to the site with me, you can go back to the lab to follow up on the progress of the experiment. Just now I contacted the section chief Tian of Binhai District Disease Control and Control, and he said that they have taken samples from the external environment and classrooms of Binhai Road Primary School, and are sending them to the laboratory of the Municipal Center for Disease Control and Prevention. ”

"Understood."

——

Binhai District, Lianhai City, Binhai Road Primary School.

Gu Yanan and Xiao Chu drove the on-site flow shunting and arrived at Binhai Road Primary School for the second flow adjustment.

As soon as the section chief of the Binhai District Disease Control and Prevention Field and his party left, the group of Gu Yanan City Disease Control and Prevention arrived again, and several school leaders came out to greet them again.

In order to avoid official greetings, Gu Yanan directly found the old school doctor and physical education teacher who knew the ins and outs of the whole thing.

Speaking of the whole thing, the old school doctor added: "Previously, Section Chief Tian of Binhai District Disease Control and Control had already checked both inside and outside the campus. ”

Gu Yanan asked, "Before the physical education incident, were there any similar cases in the school?" ”

"Yes, not much, the sporadic few are students in classes 2 and 3 of the third grade."

"Where are these two classrooms?" Gu Yanan asked.

The old school doctor raised his hand and pointed to the teaching building next to him, "The two classrooms in the middle of the second floor of this building are the second and third grade classes respectively. ”

Gu Yanan went up the stairs to the second floor and walked to the door of one of the classrooms.

Inside, students are in class, and through the open doors and windows, they can clearly see the playground outside, and one of the four small-leaved banyan trees is blocking the window.

A breeze blew, and a puff of dust mixed with the smell of leaves penetrated into the nostrils.

Xiao Chu behind him couldn't help but sneeze.

The old school doctor and physical education teacher also followed behind Gu Yanan.

Old school doctor: "This afternoon, several more students in these two classes showed symptoms of dermatitis, although the teachers and students in the whole school have more or less similar symptoms, but there are exceptionally many students in these two classes. ”

The physical education teacher reported to Gu Yanan, "When the class I led was in physical education class, it was under these four banyan trees. ”

Gu Yanan stared at the huge canopy of the small-leaved banyan tree outside the window, and frowned, "Let's go, go down and take a look at these small-leaved banyan trees." ”

On the playground, under the banyan tree.

Gu Yanan and Xiao Chu looked up at the canopy of the banyan tree.

Due to the recent dry weather, the leaves of the four banyan trees are curly, and there are many dead yellow leaves that have fallen under the trees.

Gu Yanan looked down at the fallen leaves on the ground and found that most of these leaves had traces of being gnawed by insects, and there were many yellow-brown caterpillars among them.

"Mulberry caterpillar?!"

Gu Yanan opened the sampling box and carefully put the mulberry caterpillars in the leaves on the ground into the sampling bag.

Xiao Chu assisted on the side, and at the same time discussed with Gu Yanan, "Sister Yanan, I have seen this kind of caterpillar before, I accidentally encountered it when I was a child when I went to the botanical garden, and it was full of poison, and if I was touched by it, I could feel uncomfortable for several days." Could this outbreak be related to this caterpillar? ”

"Quite possibly. There are many kinds of poisonous caterpillars, and there are no less than a dozen species that are prevalent in Lianhai City. ”

"Chrysalis? Where to find it? ”

"Dig in the dirt under the tree, you don't have to go deep."

"Looking for a shovel?"

"No, with scissors and tweezers, or even with twigs."

Gu Yanan took out a dry branch from the bushes next to him, dug in the dirt under the tree, and found several pupae.

"It's that simple? There are a lot of pupae. Xiao Chu sighed.

The old school doctor and the physical education teacher had been following the side to watch the every move of the CDC group, and seeing that they were collecting caterpillars and digging insect pupae in the soil, the old school doctor couldn't help but ask, "Do you suspect that these caterpillars caused the students' illness?" ”

Gu Yanan: "It's very likely. Poisonous caterpillars have venomous glands in the body, once the skin is punctured by the venomous burrs, patients will have dermatitis symptoms such as red rashes, pimples, wheals, etc., if the poisonous hairs enter the eyes, it will cause conjunctivitis or keratitis, and if inhaled into the lungs, it may cause asthma, all of which can explain the symptoms of current patients. ”

Although the old school doctor agreed with Gu Yanan's statement, he still had doubts, "I have seen patients infected with poisonous caterpillars before, but I have never seen such a large-scale disease, and these four big banyan trees in the school have also had caterpillars before, but the students were fine before." ”

"Were there so many caterpillars on the trees before?"

"Not really, the weather is dry this year, the leaves have been wilting, and the caterpillars have grown a lot."

Xiao Chu told Gu Yanan, "This year's climate is abnormal, especially dry, this is the case with these four big banyan trees in the primary school, and it is estimated that this will also happen in other parts of the city, which can explain the sudden increase in the number of dermatitis patients in the emergency room." ”

Gu Yanan put away the sampling box and prepared to leave with Xiao Chu, and when he left, he instructed the old school doctor and physical education teacher, "Find the school logistics to spray these banyan trees and other trees on campus with drugs to kill insects, and inform teachers and students not to go near places with trees as much as possible, especially these 4 small-leaved banyan trees." ”

——

Lianhai Center for Disease Control and Prevention, Experimental Building.

Gu Yanan and Xiao Chu sent the specimens collected at Binhai Road Primary School to the laboratory.

Lu Li and Section Chief Li of the Laboratory Department were testing the specimens sent by the Binhai District Disease Control before testing in the laboratory.

Seeing Gu Yanan and Xiao Chu coming to the laboratory, Lu Li immediately reported what he had just discovered, "Sister Yanan, we found a large number of short spines of 1~2 mm in the dust of the classroom of Binhai Road Primary School, which are suspected to be the hair of some kind of animal or insect. ”

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