According to news reports, on July 17, a confirmed case of pneumonic plague in Yumen City, Gansu Province, resulted in the death of one person. As of the afternoon of the 17th, 151 people were found to be in close contact with the patient. All of them have taken measures such as isolation, epidemiological investigation and preventive medication, and no abnormal symptoms have been found so far.
First, what is plague?
Plague is a virulent infectious disease mainly transmitted by Yersinia pestis through rat fleas. Can infect people and a variety of animals, is a natural epidemic disease widely prevalent among wild rodents. Clinically, there are three manifestations: septicemia, pneumonia and plague, including fever, severe toxemia symptoms, lymph node enlargement, pneumonia, bleeding tendency and other symptoms. Clinically, bubonic plague is the most common, of which pneumonic plague has the highest mortality rate.
Second, is plague terrible?
Plague has been prevalent many times in the history of the world, There are tens of millions of dead, Before liberation, our country also had many epidemics, with extremely high mortality rate. In human history, Yersinia pestis has been prevalent on a large scale for many times and caused extremely high mortality rate. The most famous example includes the Black Death, which is said to have killed one third of Europe’s population from 1347 to 1353. The bacterium is also likely to have caused the plague that occurred in the Eastern Roman Empire in 542 A.D.
In the history of our country, plague epidemic areas include 638 counties (banners and cities) in 21 provinces and autonomous regions, mainly distributed in northeast, north, northwest, Qinghai-Tibet Plateau, southeast coast and southern Yunnan, such as Qinghai, Tibet, Yunnan, Inner Mongolia, Xinjiang, Gansu and other regions.
Although plague is rare today, it has not completely disappeared, because it still spreads among rodents and to humans at the first chance. Even in the United States, an average of more than 10 people are infected with plague from wild rodents every year, and one in seven patients die. Although plague is not incurable and easy to control, it is still regarded by many as the most horrible disease.
What are the sources of infection of plague?
The main sources of infection are rats and other wild rodents, of which Citellus and Marmota are especially important, which are transmitted by rats and fleas.
Contact with marmots, especially dead marmots, is at risk of infection with plague. Marmots are hibernating animals and often hibernate in caves from early October to early April of the following year. Human plague in marmot foci mainly occurs in the months from the onset of sting to the hibernation of marmots, with more in summer and autumn.
Pneumonic plague patients are the source of human-to-human infection. There are also three main ways for people to be infected with Yersinia pestis: first, contact with animals suffering from plague, such as skinning and cooking; Second, it was bitten by fleas with Yersinia pestis. The third is the spread of pneumonic plague patients.
What are the transmission routes of plague?
Every time there is an epidemic of plague among rats before the epidemic of human plague, it is usually passed from wild rats to domestic rats. After the death of domestic rats, rat fleas find another host. After the rat fleas suck the blood of the diseased rats, the pathogenic bacteria multiply in large quantities in the forestomach of the fleas and become choked. When the infected fleas attach to the human body to suck blood again, besides spreading the feces containing bacteria on the skin, the bacteria-containing thrombus often invades the human body due to reflux.
Pathogens in flea feces can also be rubbed into wounds to infect people. When people crush fleas, pathogens in fleas can also enter people through wounds. This [rat-flea-human] is the main mode of transmission of human plague (glandular type).
The bubonic plague can be accompanied by septicemia and lead to pneumonic plague, Yersinia pestis in patients’ sputum can be transmitted by droplets or aerosols in a [human-to-human] manner. In addition, direct contact with phlegm, pus, skin, blood and meat of infected animals, inhalation of contaminated dust, chewing fleas, eating undercooked wild rodents, etc. also have the opportunity to become infected. Recent studies have found that the disease is likely to be transmitted by ticks.
Five, who are vulnerable to plague?
People are generally susceptible to plague. Vaccination reduces the susceptibility and has lasting immunity after the disease. The epidemic season is related to rat activity (Citellus dauricus and Marmot can hibernate with bacteria) and rat flea reproduction. In the south, it usually starts in spring and ends in summer, while in the north, it usually starts in summer and autumn and extends to winter. Pneumonic plague is mostly in winter.
What are the common symptoms of plague infection?
Mild symptoms are only irregular low fever, mild systemic symptoms, mild swelling and tenderness of local lymph nodes, and no hemorrhage. Severe cases will suffer from shock, secondary septicemia or pneumonia and die. Generally, people with respiratory symptoms or fever should receive medical observation.
Seven, how to prevent plague?
Don’t go to the epidemic area. If you have to stay in the epidemic area for a short time, you can take tetracycline or compound SMZ for prevention after the epidemic is under control.
Respiratory tract isolation should be carried out for patients to be diagnosed with pneumonic plague, while hand washing should be carried out carefully to prevent bubonic plague. Tetracycline 250 mg can be taken 4 times a day for contacts with pneumonic plague patients. People with respiratory tract symptoms or fever should receive medical observation.
Avoid contact with sick animals and their corpses, and use flea repellents.
Eight, my family has mice, will I be infected with plague?
Generally, mice need fleas to infect human beings. Direct contact with sick animals or eating also have the chance of infection. If your mice are not from epidemic areas, the infection problem is not serious and you need not worry too much. However, frequent contact with mice will cause infection of some other bacteria. It is recommended to clean the room well and eliminate mice.
This article is compiled from the Clove Garden Forum < < Brief Introduction to Points of Plague Diagnosis and Treatment > >