"So many dead birds, do you bring them all back for testing?" The person from the district disease control asked.

"Just bring some blood samples back, and bury the body deeply."

People from the disease control in the high-flying command area are looking for a place to dig a hole and bury the dead birds.

A young man who was digging a pit with a shovel asked Gao Fei, "Teacher Gao, after catching mosquitoes with a mosquito trap, are you going to use medicine to kill mosquitoes?" If you only use a mosquito trap, you won't be able to catch this mosquito at all. ”

"This time, the mosquito trap was used to catch mosquitoes, just for sampling and testing, and it should not be used to kill mosquitoes with chemical drugs on a large scale, because mosquitoes are a very important part of the entire wetland ecological environment." Goofy explained.

"If the mosquitoes are not eradicated, the West Nile virus will always exist, and as long as people enter this wetland, they can be infected?" Another young district disease control officer digging a pit asked in surprise.

"So that's the terrible consequence of the formation of a natural foci."

There was a lot of discussion among the young staff of the disease control in several districts.

"It's scary, if there is a natural foci, then this virus can survive here for a long time."

"I heard that this wetland is going to be developed into a wetland park, and now such a strange virus has suddenly appeared, and it is estimated that the development will be ruined."

"Even if someone dares to develop, who will dare to come here to play in the future?"

Zhou Lao comforted a few young people, "I don't know if this wetland has formed a natural foci of the West Nile virus, even if it has been formed, there is nothing to be afraid of, this virus has a high latent infection rate, but the fatality rate is not high, the main reason why everyone feels panicked is because the cases caused by this virus were imported cases before, and this time it is a local outbreak." ”

Gao Fei also added, "If there is a natural foci here, mosquito control work will definitely be carried out, but considering that chemical mosquito control has too much ecological impact, physical mosquito control methods should be used, and I am now worried about the situation of the villagers in several villages around the wetland park." ”

——

2:30 p.m. on the same day.

A village near the Crescent Bay Wetland Park.

Gu Yanan, Lu Li, Xiao Chu, and medical staff who were urgently transferred from the community hospital after consulting with the health authorities formed a medical team to conduct on-site physical examinations and collect nasopharyngeal swabs from all villagers in several nearby villages.

The medical team was responsible for giving the villagers a physical examination, and Gu Yanan led several members of the emergency team to check the village and its surroundings and the condition of the livestock.

The villagers in several villages are mainly engaged in farming, and every household raises chickens, ducks, poultry, cattle and sheep, and there are also many domestic animals such as cattle and sheep.

Investigating Wangjia Village at the foot of Kongwang Mountain, Gu Yanan found several mules tied to the livestock shed outside the courtyard wall of one of the villagers.

Mules are a cross between horses and donkeys, and horses are one of the terminal hosts of the West Nile virus.

Birds are the natural hosts of the West Nile virus, humans and horses are the ultimate hosts of the West Nile virus, and all the West Nile viruses are within the scope of investigation.

Approaching the barn, the stench of fermented animal manure came to my face.

Flies buzzed, and there were many mosquitoes hiding in the shadows of the barn, startled by the movement of the mules.

Lu Li covered his nose and complained, "It's too smelly, and the owner of this house doesn't know how to clean up the livestock shed." ”

Gu Yanan pointed to a dung heap not far from the livestock shed, "Animal manure is collected by the villagers, accumulated together and fermented and used as fertilizer. ”

The livestock shed was located next to the front yard, and Xiao Chu had already followed the path next to the yard to the simple fence in the backyard.

"Sister Yanan, come and see, there are a lot of horses here." Xiao Chu shouted.

Gu Yanan and Lu Li followed the shouting and went around to the backyard, and found that there was also a large livestock shed next to the backyard, with 5 horses tied to it.

This family has a lot of domestic animals and poultry, and through the simple fence, you can see that there are chicken coops and duck coops in the yard.

"These horses need to be sampled." Gu Yanan seemed to be talking to herself, she knew how difficult it was to sample these large livestock.

Especially for such large domestic animals, when the owner is not approached by strangers, not only may not be able to collect samples, but may also be injured by the animals.

Gu Yanan instructed Xiao Chu, "Go to the physical examination point at the entrance of the village to find the village chief of Wangjia Village, and ask the village chief to find this villager." ”

Xiao Chu ran away, and quickly rushed back with people.

The village chief and the villager followed behind, and when they saw Gu Yanan and his party surrounding their livestock shed, the villager panicked and asked, "Is there anything wrong with my livestock?" ”

Lu Li: "We want to take samples from your horses and mules, that is, to draw blood, and then take some mucus from the nose. ”

When the villagers heard this, they immediately shook their heads, "No, no, no, if you want to prick with a needle, these animals will definitely kick people." ”

Gu Yanan made a compromise according to the needs of the test, "If only the mucus from the nose is taken, can you guarantee the cooperation of the animals?" ”

"Yes."

Gu Yanan took the cotton swab for sampling from Lu Li's hand and greeted the villagers, "I'll go in with you." ”

Lu Li and Xiao Chu wanted to go in to help, but were stopped outside by Gu Yanan, "No, if there are too many people, these animals will be frightened." ”

Because of the help of the villagers, the sampling process went smoothly.

Out of the barn, Gu Yanan asked the villagers some questions.

"How long have these horses been raised?"

"It's been five or six years, and there were more than that, and this spring two horses got sick and died."

The villagers shook their heads regretfully as they spoke, looking very distressed.

Now the season has just entered summer, and this spring is not so long ago.

"What are the symptoms when a horse dies? Has the cause of death been investigated? Gu Yanan asked.

"Originally, when I went out to graze and graze, all the horses were fine, but when I came back, two horses began to convulse and foam at the mouth that night, and before I could go to the veterinarian, the horses died, and I don't know why."

"Grazing? Where to graze? ”

"In the woods and meadows by the lake in front of the village."

Wangjia Village is close to the wetland park, or the whole Wangjia Village is in the ecological environment of the wetland park.

This does not rule out the possibility that horses were bitten by mosquitoes in wetlands and contracted West Nile virus.

"Was there anything you were feeling sick with?"

"I can't feel distressed, I also had a fever the next day, I was sick, a horse is worth tens of thousands of dollars, the loss is too great."

Gu Yanan frowned slightly, the real situation may not be as the villagers think, the fever is due to distress, it is likely because of the West Nile virus infection.

However, all this is Gu Yanan's speculation in his heart, and laboratory test evidence is needed to confirm it.

"Is there anything wrong with you right now?" Gu Yanan continued to ask.

"Nope. Doctor, why do you want to do a medical examination for the whole village? Do you want to check my horses and mules? Is there any contagion? ”