Zhou Lao: "In addition to malaria, the prevention and control of cerebral flu in spring is also a major task, engaging in squatting, mobilizing the masses to open windows for ventilation, and investigating and treating emerging patients." The matter was not finished, and it was summer again, and cholera and Japanese encephalitis were in front of us again. ”

Lu Li: "And cholera? I haven't had a cholera epidemic since I started working. Elder Zhou, tell me about the situation of cholera prevention and control at that time. ”

Facing Lu Li's curious eyes, Zhou Lao cleared his throat and continued: "I, Zhou Jie, have worked for so many years and participated in many infectious disease prevention and control work, but the most memorable is cholera prevention and control.

Since cholera is a class A virulent infectious disease, the epidemic is kept secret from the outside world and is only called disease No. 2. Everyone knows that plague is disease No. 1, that is, the Black Death, and the harm of cholera is second only to the plague, which is called disease No. 2.

Historically, cholera was introduced into China in 1961 and Lianhai City in 1962, and in 1967 the epidemic intensity was weak and the epidemic eased, but after 1973, the incidence increased year by year, and the epidemic continued to expand, forming two high-intensity epidemics in 1978 and 1980. After 1981, the intensity of the epidemic gradually weakened, and in 1989 it fell to a low level.

I still remember the first cholera epidemic in Lianhai City in 1978, in May ~ June, the cholera epidemic in Yuntai County began to rise, and reached a peak in July and August, when the whole people mobilized to fight against the No. 2 disease, and the epidemic prevention station was fully engaged in the battle.

The laboratory receives a large number of fecal samples from diarrhoea patients and people in epidemic sites sent from commune hospitals every day, and publishes positive test results for cholera bacteria at any time through bacterial culture and identification, and many outbreaks are reported every day during the peak of the epidemic.

At that time, there were no advanced testing conditions, and PCR nucleic acid detection technology was not popularized, so the results could only be reported by primitive bacterial culture, which was time-consuming and laborious.

At that time, there was only one ambulance at the Yuntai County Health and Epidemic Prevention Station, and some communes were not connected to the road, so the epidemic prevention doctors had to ride bicycles at the grassroots level and run the scene, no matter how far they went, and the wind and rain came and went, so the epidemic prevention doctors were called "scuds" at that time.

When I was an intern, I followed the substitute teacher to go to the village for a long time, and I often went to the township and did not go home for a month or two. ”

"Wow, it's so hard, I always thought that the disease control work was busier now, but I didn't expect it to be busier before." Wang Xiaoxiao involuntarily began to sigh again.

Lu Li: "The previous epidemic prevention work is very different from the current disease control work, many diseases that used to be focused on prevention and control have now disappeared, and there are really few resurgence of filariasis. ”

Gao Fei: "The resurgence of filariasis in Shajia Village, next to Fairy Lake in Yuntai County, sounds terrifying. ”

Zhou Lao: "In fact, it is not as terrifying as imagined, in the past, the means of filariasis prevention and control were all used, and now the detection technology is so developed, it should be easier to prevent and control, and there are only a few steps to do things: on-site population census, inspection of the surrounding environment and animals, and then mosquito prevention and control, and then long-term monitoring of population microfilariae." ”

Gu Yanan echoed, "Zhou Lao is right, the prevention and control steps of all diseases are similar, and the prevention and control steps of insect-borne diseases are also similar, in addition to monitoring the infection rate of the population, and then eliminating the vector and cutting off the transmission route." ”

——

3:50 p.m.

Shajia Village, next to Fairy Lake in Yuntai County.

When the group of Gu Yanan City Disease Control and Prevention arrived, the staff of Yuntai County Disease Control and Control were already waiting at the entrance of Shajia Village.

Gu Yanan unified scheduling, divided the disease control staff into several groups, and acted separately.

One group set up a makeshift medical tent in the compound of the village committee and asked the village cadres to summon all the villagers for a medical examination.

The second group went door-to-door to sample villagers' homes, focusing on cats, dogs, cattle and sheep and other domestic animals and household pets in villagers' homes.

The three groups sampled the surrounding environment of Shajia Village, mainly to collect mosquito specimens and wild mammal blood.

Village committee compound, temporary medical center.

Disease control personnel examined the villagers gathered one by one, and Gu Yanan found that many villagers had red threads on their bodies.

After the examination, it was found that as many as 20% of the villagers had symptoms of lymphatic filariasis.

The second team led by Lu Li quickly collected the specimens from the villagers' homes, and found that many villagers had cats and dogs at home, and it took a lot of effort to collect blood from these cats and dogs.

The three groups led by Xiong, the head of the county disease control department, also quickly completed the sampling of the surrounding environment of Shajia Village.

Section Chief Xiong returned from sampling and reported the situation to Gu Yanan, "Director Gu, Shajia Village is next to Fairy Lake, the surrounding environment is watery, many mosquitoes breed, it is easy to catch mosquitoes, and it takes a lot of effort to completely eliminate mosquitoes." ”

The collected specimens were urgently sent to the Municipal Disease Control Laboratory by Gu Yanan, and she remained in Shajia Village to prepare for the blood collection work that night.

It was 10 o'clock that night.

The villagers were then summoned to the village committee compound to collect blood.

The earlobe blood was collected and directly stained for microscopic examination with the equipment brought.

In the blood smear, microfilariae were found.

Microfilariaeemia!

Sure enough, it was filariasis.

Day 2 at 8:20 a.m.

Section Chief Li of the Municipal Disease Control Laboratory sent Gu Yanan a test report of yesterday's specimens.

Heartworm nucleic acid was detected in three hospitalized patients, and the subtype was identified as Malayan heartworm.

Villagers in Shajia Village have also been tested positive for Malacana nucleic acid.

The positivity rate is as high as 31%, which is higher than the 24% positivity rate of microfilariaemia that Gu Yanan did last night.

Of the 76 cat blood samples collected from the homes of villagers in Shajia Village, 18 were found to be positive for Malayan filaria.

Domestic cats have been shown to be storage hosts for Malayan heartworms.

Mosquito samples collected from the surrounding environment of Shajia Village were also found to be positive for Malayan filarial worm nucleic acid.

Vector mosquitoes have also been confirmed to carry Malayan filaria.

The complete chain of transmission is clearly in front of you.

In the temporary epidemic headquarters of the village committee compound, Gu Yanan showed the test report to several members of the emergency team.

Zhou Lao: "As expected, it is Malayan filariasis, which has a natural host in nature, and cats are the natural host. Even if there are no people, as long as there are suitable conditions for mosquitoes to grow, and there are mammals such as domestic cats or wild cats, mosquitoes bite cats, forming a closed chain of transmission. Mosquitoes infected with microfilariae bite people and then introduce filariasis to humans, which is a typical disease with natural foci. ”

Wang Xiaoxiao followed several members of the emergency team to stay awake all night, and when she saw the test results, although she was a little sleepy, she was still very excited, "The number of patients has been identified, and the transmission route and source of infection have been found, what should I do next?" ”

Zhou Lao: "This is simple, it is to cure the disease and save people, eliminate the source of infection and transmission routes, and to put it bluntly, it is to cure the disease and eliminate mosquitoes." ”

Gao Fei: "It sounds like it's quite simple, leave the treatment to the hospital, and we will guide the county disease control and the villagers to get rid of mosquitoes." ”

Gu Yanan: "Not only that, but the scope of our CDC investigation is not only Shajia Village, but also all villages within a radius of 5 kilometers centered on Fairy Lake. ”

Lu Li found the electronic map, "With Fairy Lake as the center, there are a total of seven villages within a radius of five kilometers, four of which are around Fairy Lake, and the other three are slightly farther away. ”

Wang Xiaoxiao: "It took us two days and one night to check a village, and it took half a month to check 7." ”