The plague ( Latin pestis " plague , epidemic , bubonic plague", Greek also λοιμός, loimos ; English plague ), outdated also called pestilence (Latin pestilentia ), is a highly contagious infectious disease caused by the bacterium Yersinia pestis . It can come in different forms, including bubonic plague (bubonic plague) and pulmonary plague .
Originally the disease is a zoonosis , i.e. a disease that can be transmitted from animals to humans and vice versa, that came from rodents ( marmots , rats , squirrels ), in whose populations it can be enzootic . It is traditionally transmitted to humans through the bite of an infected flea , but direct human-to-human infection via droplet infection is also possible.
In Germany, Austria and Switzerland, the plague is a reportable disease .
As the so-called Black Death , the plague led to the most devastating epidemics in human history in the 14th century and probably with the Justinian plague as well in the 6th century . A historical overview of the disease and epidemics, also known as the plague, which claimed many lives, can be found under History of the plague .
The plague is triggered in humans and animals by the bacterium Yersinia pestis (formerly divided into Yersinia pestis orientalis , Yersinia pestis antiqua and Yersinia pestis medievalis ). This bacterium, a mutation of the Yersinia pseudotuberculosis bacterium , which is relatively harmless to humans , is very adaptable and many different variants have been described. The pathogenic properties of Yersinia pestis arise from ectotoxin , endotoxin and bacterial capsule formation .
The spread of the plague depends on the spread of the intermediate hosts . Wherever these are found, plague cases are always possible. Whether they can grow into epidemics depends on several factors, such as the resistance of the bacteria to drugs, the prevailing hygienic conditions and the fight against the local intermediate hosts.
Chain of infection
The plague can be transmitted in different ways: on the one hand by the bite of insects contaminated with pathogens , mainly fleas , on the other hand by droplet infection . The latter type of transmission leads to primary pulmonary plague.
In abbreviated form, the typical path of infection in bubonic plague runs "from rat - rat flea - human, human - human flea - human [...] and further with pulmonary plague through droplet infection from person to person".
The intermediate link in transmission from rats to humans is the flea. Paul-Louis Simond was the first to discover this connection in 1898. In first place is the tropical flea Xenopsylla cheopis (rat flea). About the conditions and mechanisms of the spread of the plague by this flea see there . This flea hardy does not occur in Europe because the weather conditions are too cool for this species. AW Bacot suspected that the human flea ( Pulex irritans ), which is widespread in Europe and is characterized by a wide range of host animals, is responsible for the transmission. The researchers Hariette Chick and CJ Martin suggested Nosopsyllus fasciatus (= Ceratopsyllus fasciatus ) as a vector. This flea hard makes up half of all fleas in England. Both of these species can cope with lower temperatures than Xenopsylla cheopis . In addition, its eggs die at 13 ° C, so that Bacot said that at least 15.5 ° C had to be present in order to keep its flea population alive. In contrast, some of the eggs from Pulex irritans survived at 8 ° C, and half of the eggs from Nosopsyllus fasciatus even survived temperatures of 5 ° C. Today we assume a temperature window of 0 to 40 ° C for this flea. Nosopsyllus fasciatus and Pulex irritans are found widespread in England, Wales, Scotland, the Shetlands, the Orkneys and Ireland.
These types of fleas differ in their vector effectiveness. This describes the effectiveness with which a fleaf is able to transmit disease. CM Wheeler and JR Douglas considered the vector effectiveness to be dependent on three potentials, each of which is a measure for the following question:
- The infection potential: How many individuals in a flea population suck blood with plague bacteria?
- The infectious potential: How many of these fleas can cause a plague by themselves because their digestive tract is blocked?
- The transmission potential: How often can a single flea transmit the infection before it dies or the blockage is broken?
The vector index was then introduced in order to be able to compare the various flea species with one another on this point. The Xenopsylla species were used as a benchmark. Nosopsyllus fasciatus comes closest to these. In contrast, Pulex irritans shows low vector effectiveness, similar to cat and dog fleas , because the necessary blockage by bacterial clumps rarely occurs in them. In laboratory tests, Nosopsyllus fasciatus came in second behind Xenopsylla cheopis . In Pulex irritans , only one in 57 specimens was blocked, and that specimen died before it could pass the infection on. Georges Blanc and Marcel Baltazard took a different approach: In the plague of 1940 in Morocco , they caught Pulex irritans in the houses of those who had died of the plague in Marrakech , crushed them and injected their solution into guinea pigs, who soon died of plague. In doing so, they drew attention to the possibility that the plague could be transmitted directly from the human flea without a rat, which they pointed out in another publication. The Moroccan houses were full of human fleas. Of a good 3500 fleas collected, 3000 were Pulex irritans , while only about 600 specimens Xenopsylla cheopis were found. On the other hand, Georges Girard objected that the plague epidemics in India, Senegal and Madagascar differed greatly from the Moroccan ones, although Pulex irritans had also occurred in abundance there. Incidentally, from his experience he denied the effectiveness of Pulex irritans as a transmission vector . But he thought it possible that the amount of fleas in Morocco made up for the lack of effectiveness. Other studies of plague in North Africa, particularly Egypt, showed that the human flea was not involved in spreading the plague, although it was highly infected by the plague. Atilio Macchiavello, on the other hand, found the complete absence of Xenopsylla cheopis in a plague outbreak in Peru in 1946 at an altitude of 600–700 m. Robert Pollitzer and Karl F. Meyer then determined the transmission of the plague by fleas in more detail than massive infestation by fleas whose suction tools were infected by previous infestation by rodents (mechanical transmission), or as bites from fleas blocked in the digestive system (biological transmission). In North America, the main vector of animal-to-human plague is the flea Oropsylla montana , although it does not block.
A major factor in the transmission of the plague by the flea is the number of bacteria it injects with one bite. Ole Jørgen Benedictow assumed 25,000 bacteria per bite of a blocked flea. However, the numbers were very imprecise before the introduction of the PCR technique . Using this method, around 100,000 Yersinia pestis bacteria were found in the infected specimens.
Studies of fleas in New Mexico and Colorado also found a connection between bacterial concentration and the microenvironment of the fleas: Fleas that had detached from the host animal and buried in the ground had higher concentrations than those in the fur of the host animal. The fleas picked up from the ground were not all infected, but those that were had sufficient concentration to block it, while for fleas in the fur of a host animal, this was only the case for 1 in 50 fleas. On the other hand, the infection rate was higher in the latter.
The stay of fleas outside of host animals in nests and in the ground is not a special behavior of certain types of fleas, so that the distinction between fur fleas and nest fleas does not lead any further. Pollitzer and Meyer found that there is no dividing line between nest fleas and fur fleas. The different behavior in this connection between Xenopsylla cheopis and Nosopsyllus fasciatus is based on their eating habits: cheopis often bites and therefore rarely and only briefly leaves the host animal, while fasciatus bites less often and therefore lives without a host animal for a long time. According to Pollitzer and Meyer, this is not related to the species, but to the climate in which the fleas live: cheopis in tropical latitudes, fasciatus in cooler areas. Based on these findings, fasciatus is not necessarily a worse plague vector than cheopis .
Warm-blooded host animals
It has been shown that the plague can affect over 200 species of mammals, so it is not limited to rats. It has also been found in dogs and cats. In addition to the brown to black house rat ( Rattus rattus ) and the gray-brown brown rat ( Rattus norvegicus ), the house mouse ( Mus musculus ) was also attributed to triggering epidemics, such as those in southeast Russia in the 1920s and in Brazil 1936–1945 and in Saigon 1943. Nevertheless, the house mouse only plays a subordinate role in this context, since it does not develop the high bacterial concentration in the blood that is required (Pollitzer 1954 pp. 299-300). In addition, their flea Leptopsylla segnis is a poor vector . It only takes in a small amount of plague bacteria. The flea is also highly fixated on the mouse. The rats were therefore always in the foreground. This was based on the observation during the plague in Bombay in 1905 that there was an overabundance of rats of both species there at that time. The commission observed that the brown rat was first affected by the disease, the common rat about 10 days later, and the peak of the human mortality rate occurred less than 1 month later. In 1910, a few kilometers from Ipswich, several people died of a bacteriologically identified plague. Then rats were hunted and of the 568 specimens caught, 17 had plague bacteria. Everyone in this rural area were brown rats. But it is believed that the black rat was the main mediator of the plague epidemic from India in 1898 to Madagascar in 1998. The flea only stays with live animals. As soon as the infected organism cools down, the flea leaves the host. Since guinea pigs are often eaten in South America , infections have occurred again and again in recent times.
If a sufficient number of bacteria have entered the bloodstream during the infection that the body's own defenses can no longer master it, a high concentration of bacteria in the blood occurs after a short time, which then leads to sepsis .
The blood-poisoning effect is triggered when the bacteria complete their normal life cycle and die. Large amounts of toxic secretions are released directly into the bloodstream; The kidneys and liver can become necrotic when trying to cleanse the body of toxins . In the end, the victim succumbs to a toxic shock.
There are four manifestations of the plague: bubonic plague , also called bubone plague (Greek bubo "bump"), plague sepsis , pulmonary plague and the abortive plague . In pandemics all forms occur the disease, but most often the bubonic plague and pneumonic plague. Without treatment, bubonic plague often develops into plague sepsis, which leads to pulmonary plague. Plague meningitis also rarely occurs when the haematogenous spread of the plague pathogens ( Yersinia pestis ) attacks the meninges after bubonic plague.
As Hautpest is called the (secondary) due to the bubonic plague skin symptoms occur. The primary skin plague with roseoles, carbuncles and often extensive skin and mucous membrane bleeding, which contributed to the designation of the plague as the Black Death , is less common .
In bubonic plague or bubone plague (from Latin bubo , "bump", here: inflammation of the lymph glands, particularly inflammation of the inguinal glands), infection usually occurs through the bite of a rat flea , which carries the pathogen as an intermediate host. When the host changes , the bacterium is transferred from an infected to a previously healthy food victim after it has multiplied in the flea. In addition to the transmission from rats via rat fleas to humans, there is also a transmission path via human fleas from humans to humans.
The incubation period is a few hours to seven days. The symptoms are fever , headache and body aches, feeling very sick, and drowsiness. Disturbances in consciousness occur later. The name bubonic plague comes from the severely swollen, very painful bumps (bubons, which can form a package of swollen lymph nodes of the secondary complex) on the neck, in the armpits and in the groins (axillary and inguinal bubons) caused by the infection of the lymph nodes and lymph vessels arise in the area of the flea bite. These bumps or “glandular swellings” can reach a diameter of up to ten centimeters and are blue-black in color due to internal bleeding in the lymph nodes. The tumors disintegrate after they are purulent melted down.
The (primary) plague sepsis occurs when bacteria enter the bloodstream from their place of reproduction. This can happen through infection from the outside, for example through open wounds, but also as a complication from the other two severe forms, for example through the bursting of the plague bumps inwards. The pathogens in the blood are distributed with the bloodstream throughout the body. The infection causes high fever , chills , headache , dizziness and a general malaise, later shock, extensive skin and organ bleeding (hence the name "black death"). If left untreated, plague sepsis is almost always fatal, usually after 36 hours at the latest.
Today, treatment with antibiotics can significantly reduce mortality.
The highly infectious lung plague , which is transmitted by droplet infection , is relatively rare today. It is the only form of plague with a specific path of infection and spreading pattern. It is likely to be similar to influenza , although the force of spread is much weaker. The spread is so specific that it can only become an epidemic under particularly favorable circumstances. First of all, the sources of infection are rare. Only a small part of the population infected with the plague gets pneumonic plague, for example in the presence of bubonic plague and weak resistance. You can be infected by mammals, but these are usually pets. In the 21st century, for example, most patients with pneumonic plague in America had contracted infected cats.
The physical proximity to the source of the plague is another requirement. The critical distance to the face of a person with pneumonia for infection is 30 cm and below. In contrast to the influenza viruses, the plague bacteria die quickly in the air. Another factor that reduces the spread is that the infected die very quickly, leaving only a short period of time in which the pulmonary plague can be passed on. The incubation period is given as 1 to 3 days, the mortality rate is 95%, and the infectious coughing up blood only occurs in the advanced stages of the disease.
Nonetheless, pulmonary plague epidemics are documented in the 20th century that were triggered by travelers infected with the plague. The two largest pneumonic plague epidemics occurred in the Chinese border region of Manchuria at the beginning of the 20th century . The occurrence was mainly linked to a cold climate. The epidemic in Manchuria 1910–1911 took place in winter (September to April) and was linked to the main traffic routes. The plague was transported over 2,700 km in 7 months. At least 60,000 people died of the plague.
Wu Lien-Teh observed that the lung plague in Manchuria was linked to the hunt for the Tabargan or Siberian marmots ( Marmota sibirica ) and was due to the valuable fur. Before 1910 the price of the skins had quadrupled. Today's experience has shown that pneumonic plague occurs regularly with the disease of rodent populations. The connection between pneumonic plague and a previous rodent disease with epidemic bubonic plague is well documented.
If the pathogens of a bubonic plague get into the lungs via the bloodstream in the course of plague sepsis, it is referred to as secondary pulmonary plague . However, if it is transmitted from person to person through a droplet infection , it is referred to as primary pulmonary plague .
The lung plague is more violent than the bubonic plague because the defense barriers of the lymph nodes are bypassed by direct infection of the lungs. It begins with shortness of breath , coughing , blue lips and black-blooded sputum , which is extremely painful to cough up. This results in pulmonary edema with circulatory failure which, if left untreated, leads to death after two to five days.
The abortive plague is the harmless variant of the plague. It usually only manifests itself in a slight fever and slight swelling of the lymph nodes . Once the infection has been overcome, antibodies are formed that ensure long-lasting immunity against all forms of the disease.
The diagnosis is made by detecting the pathogen in the blood, in the secretion of the bumps or, in the case of pulmonary plague, in the sputum. The French-Malagasy research team led by Suzanne Chanteau from the Institut Pasteur de Madagascar (IPM) developed a rapid test for both pulmonary and bubonic plague in 2003, with which antibodies can be detected within 15 minutes. Before that, both diseases could only be detected after an evaluation period of 14 days.
With the 4,000 cases of plague occurring worldwide every year, a rapid diagnosis within 24 hours is a crucial part of successful treatment. The plague still occurs in 20 countries, especially in Africa.
The initially ambiguous and often only weak symptoms have so far usually required bacteriological examinations, sometimes even via the DNA for a clear assignment. Confusion with appendicitis , meningitis and streptococcal infections are documented in the USA .
The spread of the plague in the epidemics of 1910 and 1921 is also due to the development of the means of transport. In 1921 the plague occurred mainly at the railway stations from Harbin to Vladivostok . Harbin was the junction between the Trans-Siberian and East China Railways and was particularly hard hit. But traveling on horseback also spread the plague over long distances, as the plague outbreaks of 1878–1925 in Astrakhan and the southern Urals prove, where there were no rail connections. Over 5,000 people died, 70% of them from pneumonic plague. The unsanitary living conditions there were to blame for the outbreak: dark, dirty and overcrowded. 10–15 people lived in about 10 m². People rarely or never washed and never changed clothes. The plague sufferers were visited by many people, and the guests wiped the sputum with hands or clothes. This was true of the plague epidemic of 1910, where the Tarbagan -Jäger itself as the first in the hunt for marmots for the production of marble skins ansteckten to the contaminated animals. They slept in particularly small huts, up to 40 men in bunks, which encouraged the spread. The conditions at the bitumen pits at Lake Dalai Nur were a further indication . During the plague epidemic of 1921, 4,000 Chinese and 2,000 Russians worked there. Of the total of 1,027 dead, only 4 were Russians. The Chinese lived crammed into small huts, half buried in the ground, the Russians lived in houses above ground. The transmission of pneumonic plague by droplet infection certainly occurred at the beginning of the 20th century.
Course of an epidemic
The endemic course of the plague follows a pattern that is typical of this epidemic, which cannot be found in any other epidemic: death sets in faster and faster in rats after infesting a colony. While initially with about 7 fleas per rat these show a normal course of the disease, the infestation with the decimation of the colony in the remaining rats becomes stronger, so that 50 to 100 fleas per rat occur, which leads to a significantly higher contamination. After 10 to 14 days, the rat colony is so reduced that the fleas can hardly find any hosts. This period of 10 to 14 days is the first important phase of diffusion. Thereafter, the fleas do not ingest blood for about 3 days until their urge is so great that, since they cannot find rats, they now attack humans. The incubation period of 3 to 5 days follows . This is followed by the disease period of 3 to 5 days, which leads to death in the majority of those affected. It takes an average of 8 days from infection to death. It takes 20 to 28 days from the initial infection of a rat colony to the first death, usually 24 days.
Contact between contaminated and fresh rat colonies results in slow spread. More important is the spreading process through the visitors. They take the contaminated fleas home with them and infect their own rat colony. This means that this form of spread only has an effect when the plague has visibly broken out in a person, so that in the late Middle Ages this form of spread with an ambulance, wake, funeral service and division of inheritance began. This point in time is reached about 3 to 4 weeks after the plague has been introduced into a location. A week later the plague has spread to the home courtyards of the visitors and the epidemic phase begins. So up to then about 40 days or 5½ weeks have passed.
Another typical feature of the plague epidemic is collapse in winter. There is no known bubonic plague epidemic in one winter. This is due to the fact that the septic bacteria density in the rats is lower when it is cold , so that the fleas ingest less bacteria, and with the fact that the fleas do not multiply when it is cold. The end of the plague epidemics, which are spread by fleas, regularly falls in the winter months. If the plague was only introduced in late autumn, it did not break out until the following spring.
Wild rodent populations as a retreat for the plague bacterium
The plague bacteria are still found in wild rodent populations today - such as prairie dogs , ground squirrels and marmots . These populations are the natural reservoirs of the plague bacteria from which domestic rodents such as rats are occasionally infected.
While no infected animal populations are known in Europe and Australia , they occur in the Caucasus , Russia , Southeast Asia , the People's Republic of China , Mongolia , South and East Africa , Central and South America and the southwest of the USA .
The pathogen reached North America via a merchant ship during a plague epidemic that raged in Southeast Asia from 1894. Although very few people in North America contracted the plague, the pathogen infected the American squirrel population. Occasionally, animal-to-human transmissions still occur in North America today. Usually it is hunters who get infected from a rodent. Norman F. Cantor also refers to a North American case from the 1980s, in which a woman ran over a gray squirrel with a lawnmower and became infected with the plague.
The World Health Organization (WHO) registers around one thousand to three thousand cases of plague worldwide each year, mostly in the form of small, localized epidemics. The last documented plague outbreak in Europe occurred during World War II . It is believed that the plague no longer exists in Europe.
Nowadays, the plague is treated with antibiotics for 10 days. If diagnosed early, there is a good chance of a cure. Active ingredients used are, for example, streptomycin or gentamicin and chloramphenicol, and combinations of tetracyclines and sulfonamides . Chloramphenicol is highly effective, but due to its side effects, it is only considered a reserve drug. The antibiotics doxycycline and ciprofloxacin , which are also used for treatment, may be used prophylactically and administered over seven days . Lethality increases exponentially as the disease progresses.
Inhibitors are currently being developed to block an enzyme in the bacterium that plays an important role in the structure of the cell protective membrane, without which the bacterium cannot survive.
There are vaccinations available, but an immunity grant only for three to six months, and only in the bubonic plague, but not for the pneumonic plague. The authors Eberhard-Metzger and Ries, however, point out that these vaccinations are not well tolerated. The World Health Organization therefore recommends vaccination only in groups at risk, including farmers , farm workers and hunters in regions where infected rodent populations are common.
Other measures to contain a plague epidemic include improved hygiene , control of rats and preventing rats from being transported on ships. Since the fleas change host after the death of the rats, people have to be protected from the fleas with insecticides .
In addition to hemorrhagic fevers ( Ebola , Lassa and others) in Germany, the plague or plague fever is one of the two quarantine diseases according to Section 30 of the Infection Protection Act . Such sick patients must be shielded in special infection departments. Cross-border quarantine regulations for ship, air, train or motor vehicle traffic are laid down in the International Health Regulations of 1971. A reference to the plague, illness from or death from plague must be reported by name in Germany according to the Infection Protection Act even if there is suspicion ( the Infection Protection Act). The reports are forwarded by the health authorities to the state health authority and the Robert Koch Institute . The Robert Koch Institute reports them to the World Health Organization in accordance with international agreements .
Genetic studies of a 3800-year-old grave in the Russian region of Samara in 2018 were able to reconstruct two Yersinia pestis genomes that were circulating at the same time. One of these has the genes that are believed to be characteristic of bubonic plague and is the ancestor of today's tribes. The age of this lineage was calculated to be 4000 years.
For a long time it was controversial whether the Justinian Plague of late antiquity , which hit Europe and the Middle East from 541 and disappeared again around 770, was caused by a pathogen from the Yersinia pestis tribe . Finally, at the beginning of 2013, an international study carried out in parallel at various laboratories under the direction of Michaela Harbeck and Holger C. Scholz, based on DNA material from graves in Aschheim , which can clearly be dated to the later 6th century, showed that this was the case The first verifiable plague in the narrower sense was actually about the pathogen Yersinia pestis .
In addition, a phylogenetic classification of the pathogen concerned between the early pedigree branches N03 and N05 was successful. According to the current state of research, it can therefore be considered almost certain that a pathogen from the Yersinia pestis tribe was at least prominently involved in the Justinian plague and that the plague was actually the plague. Until 2013, many researchers believed that the first outbreak of the disease was the Black Death from 1347 to 1351. It is still unclear why the plague seems to have disappeared from Europe for several centuries around 770.
The modern description of the disease began with the plague pandemic in Indochina in 1890. Alexandre Yersin , who was doing research at the same time as the Japanese Kitasato (researcher of the plague in Hong Kong), discovered the Yersinia pestis bacillus named after him, which was named Pasteurella pestis until 1944, on June 20, 1894, isolated it and assigned it to the plague. At the same time, the French Paul-Louis Simond discovered the spread of the black rat ( Rattus rattus ) to humans via the oriental rat flea in India .
This led to the description of the plague as a single disease. The discovery of the spread of the plague in India had a dominant role in the view of the plague as it is today as a modern disease. It initially led to the view that there was only this one way of spreading the disease. Meanwhile, research has expanded to include large numbers of rodents and large numbers of flea species. The high mortality in the colonies led to increased research efforts with a cartography of the epidemic features. The starting point that was not questioned was that it was always about the plague. The disease was given the historical term plague and the bacteria were named after it. The identity of the medieval plague with the plague researched in India was assumed. When researching the plague and its spread, the specifications of the English plague research commission, which had been sent to India in 1905, were decisive.
Many research groups traveled to India, including a German one with scientists from Robert Koch's area . In 1897 they stated: "It is reported from many places that the outbreak of the plague was preceded by an epidemic disease and massive deaths of rats." An English commission appointed by the Indian viceroy announced in 1910 that the plague epidemic in India was directly related to the plague in the Rat population is dependent. No evidence was found for animals other than host animals. The commission distinguished between bubonic plague and other clinical forms. All observations indicated that the plague epidemics occurred exclusively in the form of the bubonic plague.
It has been proven that the rats were infected by fleas. (For detection, healthy and sick rats were kept separate, the separation being permeable to the fleas). With regard to the human plague, the commission drew a number of conclusions: 1. The plague is not transmitted from person to person because the nurses in the hospitals did not become infected. 2. In their opinion, the epidemic was firmly linked to the epidemic among rats. 3. The predominant flea hardy in India, Pulex cheopis , today Xenopsylla cheopis , had proven to be one that also attacked humans, especially when their natural host animals were missing. Repeated experiments with guinea pigs and monkeys in plague-infested houses showed that they fell ill if they were not protected against fleas. Neither plague-infested soil nor the clothes or bedding of plague sufferers were able to infect with plague without fleas. Since the commission found experimentally that the plague bacteria could only survive outside a host animal for a few days, it came to the conclusion that the plague in the country towns must have been brought in from outside. Since the plague also occurred in the big cities outside of the plague-prone months, she said that the plague remained there in small rat populations or individual people as a reservoir between the plague seasons. In a study area the size of India, the question of the ways in which it spreads arose. Since the rats could hardly travel long distances, the commission said that the spread in previously pest-free zones must have taken place through the movement of goods. These investigations and conclusions related exclusively to the bubonic plague that occurred in India at the time.
In 2011, the genome of the Yersinia pestis strain was described, which infected people in England from 1348 to 1350 during the time of the "Black Death".
The results can be used to better understand the evolution of pathogens. According to the study, the plague pathogens have hardly changed since the epidemic between 1348 and 1353. Suspicions that the pathogen originated in East Asia in the 13th or 14th century, which meant that earlier plague epidemics such as the Justinian plague , which killed more than 100 million people worldwide in the 6th century, had not yet been identified by another If the pathogen had been caused, it turned out to be wrong at the beginning of 2013: The infections from the 6th century can also be traced back to the pathogen Yersinia pestis. The researchers obtained the genetic material of the centuries-old plague pathogen from the skeletons of plague victims who were buried in East Smithfield Cemetery in London in the Middle Ages. This cemetery is considered to be the best documented plague cemetery in all of Europe; it was only used for three years - from 1348 to 1350.
The plague today
The plague is now one of the “forgotten” diseases that can be treated well, but can still be fatal if discovered too late. In addition to the traditional host and intermediate host carriers such as fleas and rats, which u. a. Can be combated well with hygiene measures, the outbreaks today are often linked to marmots, prairie dogs, ground squirrels, but also to wild cats, hares and rabbits. Outbreaks therefore occur almost worldwide, but are rare and, with the exception of Madagascar, could usually be narrowed down quickly and only reach low case numbers. In the early stages of the disease, due to the first symptoms, a great danger is mistaking it for a cold, which can best be ruled out by a doctor's differential diagnosis (disease symptoms and belonging to a risk group). From 1978 to 1992, the World Health Organization (WHO) reported 1,451 deaths in 21 countries. In the United States, for example, there were thirteen infections and two deaths in 1992.
Worldwide plague events
A major plague epidemic occurred in Surat, India, from August to October 1994 . The WHO counted 6,344 suspected and 234 proven plague cases with 56 deaths. The plague pathogen found there had properties that had not yet been observed. It was characterized by a weak virulence and is considered to be a new strain of pathogen due to some molecular biological characteristics.
In 2003 there was another plague outbreak in Algeria after 50 years.
In February 2005, pneumonic plague spread in Bas-Uele in the north of the Democratic Republic of the Congo . According to WHO reports, there were 64 deaths. The intervention of the organization Doctors Without Borders prevented further spread. On June 14, 2006, 100 deaths from the plague were reported in the Congo, with the most severely affected region being the Ituri district in the northeast with up to 1,000 cases per year of both pulmonary plague and bubonic plague.
In November 2008, a new outbreak of the disease in Uganda was reported in local newspapers. A total of twelve people were affected, three of whom died.
Plague cases are recurring in the southwestern US states. The silvatic reservoir of pathogens is formed here by prairie dogs . If sick prairie dogs are preyed on by domestic cats, 10% of them develop lung plague and excrete large amounts of the pathogen. They are then a source of infection for the pet owner and other contact persons. A total of ten to twenty people fall ill with the plague in the United States each year, with the numbers falling. The Oslo biologist Nils Christian Stenseth attributes this to climate change . At the beginning of August 2009, eleven people in Ziketan in the Tibetan province of Qinghai in northwest China were found to be infected with pneumonic plague. A person died. In 2014, a small Chinese town was quarantined after a man died of the plague.
At the beginning of June 2018, according to the news magazine Stern in the US state of Idaho , the bubonic plague was found in a person. The last case of the bubonic plague in Idaho was 26 years ago.
In 2019, a couple died in Mongolia after eating a suspected infected marmot.
Plague incidence in Madagascar since 2008
In early 2008, the plague broke out in Madagascar , killing 18 people. In 2010, 18 people died. From the beginning of the year to March 2011, 60 people died and another 200 became ill. Remote regions such as the area around the town of Ambilobe in the northwest are particularly affected, and there were other cases in the east and in the highlands.
At the end of 2013, 20 people died of pneumonic plague in the remote north of the tropical island of Madagascar in the Mandritsara district . Since September 2013, 36 people have fallen victim to the infectious disease in four different districts in Madagascar.
In 2014, at least 40 people died again in Madagascar in a plague outbreak that was still rampant in mid-November.
In late October 2017 it was reported that the death toll from the recent plague outbreak in Madagascar rose to 107. More than 1100 people have been infected with the disease, almost 700 of which have been cured so far. Around 600 people have died of plague in Madagascar since 2010.
Since the plague epidemic of 1348 arose Pestbilder that should the divine wrath, represented picturesque mostly in the form of arrows or spears, symbolizing as an explanation for the disease. Often in these pictures a protective cloak Madonna is shown protecting against this wrath of God or the patron saint Sebastian or Rochus are shown. In many places, splendid pillars of plague were erected in gratitude for the end of the plague epidemics .
The Oberammergau Passion Play takes place as the redemption of a promise after surviving the plague in 1634. They have been held every ten years since 1680 and are among the world's most famous passion plays. Similarly, in the city of Flörsheim am Main since 1666 until the present day, the so-called “Fiancé Day” has been celebrated as a local holiday on the last Monday in August in thanks for sparing the population from the plague.
On March 5, 1838, the opera Guido et Ginevra ou la Peste de Florence by Fromental Halévy based on a libretto by Eugène Scribes was premiered at the Paris Opera . The action takes place in Tuscany in 1552 . In 1881 the Danish writer Jens Peter Jacobsen published the novella Pesten i Bergamo (“The Plague in Bergamo”). Arnold Böcklin created the picture The Plague or The Black Death on this subject in Italy in 1898 , which is exhibited today in the Kunstmuseum Basel . Böcklin personifies the plague in his picture as a grim reaper riding on a flying monster , from whom there is no escape. The scythe and the skeletal figure draw on the medieval allegory of death .
Based on a screenplay by Fritz Lang , the first film in the monumental film series Decla - World Class, was the silent film The Plague in Florence , in which the plague afflicts Renaissance Florence. In the last sequence of the film, a personification of the plague moves through the city dancing and playing the violin as a form of dance of death . The depiction of the plague shows very clear references to Arnold Böcklin's painting. In 1921/1922, Friedrich Wilhelm Murnau shot the silent film Nosferatu - A Symphony of Horror , in which a vampire is symbolically equated with the plague and represents its visual and physical personification. This metaphor is worked out even more clearly in Werner Herzog's sound film adaptation Nosferatu - Phantom of the Night (1979) with Klaus Kinski in the title role. In his epidemic drama Blown Traces , shot in 1938 , an adaptation of the radio play of the same name by Hans Rothe , Veit Harlan describes an allegedly authentic plague during the first Paris World Exhibition in 1867. Ingmar Bergman shot the seventh seal ( Det sjunde inseglet ) with Max von Sydow in 1957 , the film deals with a plague epidemic in 14th century Sweden.
Albert Camus wrote the novel Die Pest (French La Peste ) about a modern plague outbreak in the Algerian city of Oran (published 1947). In it a doctor meets humanity and solidarity despite the hopelessness and absurdity of the fight against the plague. The plague is often interpreted as a symbol for National Socialism . Four years earlier, Raoul Maria de Àngelis published the novel La peste a Urana ("The plague in Urana"). Even Marcel Pagnol wrote a story about the plague. Its theme is the devastation of Marseille in 1720. Les Pestiférés appeared posthumously in 1977 in Volume IV of the Souvenirs d'Enfance , Le Temps des Amours . In 1973, the play Il sonno dei carnefici ("The Gravedigger's Dream"), performed in Spoleto in 1975, by the biologist and writer Giorgio Celli, deals with the plague in Seville.
The plague pathogen as a biological weapon
The World Health Organization counts the plague pathogen among the twelve most dangerous biological warfare agents . These so-called dirty dozen also include anthrax and tularemia as well as smallpox , Ebola and Marburg viruses .
There is the popular hypothesis that the plague was used as a biological weapon as early as the 14th century - when in 1346 in the Genoese port city of Kaffa in the Crimea the Tatar leader Dschanibek had plague bodies thrown over the walls of the city and the besieged before the plague to Italy fled. According to a report by Gabriel des Mussis from Piacenza, Genoese and Venetians who were involved in the siege of Kaffa are said to have brought the plague with galleys to Messina, Pisa, Genoa and Venice, from where it then spread throughout Italy. However, this is viewed controversially and has not been clearly proven.
During the second Sino-Japanese War presented the Japanese Army in unit 731 prison camp called at Harbin in Manchuria biological weapons ago, which consisted of those infected with the plague fleas and their use in the Republic of China caused in the years 1940 to 1942 local Pestausbrüche. When the production facilities were destroyed by the Japanese army at the end of the war in 1945, rats infected with the plague were released and triggered an epidemic in the Chinese provinces of Heilongjiang and Jilin with over 20,000 deaths. During the Cold War , Soviet scientists from the Directorate-15 worked in the military research complex Biopreparat under the direction of Ken Alibek on the use of plague pathogens as a biological weapon.
In Germany, the Robert Koch Institute deals with the dangers of biological warfare. The Federal Information Center for Biosafety (IBBS) was also set up there. How great the risk of attack with biological warfare agents actually is is controversial. The IBBS does not recommend vaccination against the plague in Germany. This recommendation applies both to the general population and to risk groups.
On August 28, 2014, the magazine Foreign Policy reported on a computer found in a hiding place of the organization " Islamic State " which, among other things, contained instructions for the creation of bubonic plague weapons.
In Austria, it is a notifiable disease in accordance with (1) of the Epidemic Act 1950 (suspected illnesses and deaths).
In Switzerland, plague is also a reportable disease according to the Epidemics Act (EpG) in conjunction with the Epidemics Ordinance and the Ordinance of the FDHA on the reporting of observations of communicable diseases in humans (reporting of clinical suspicion, consultation with a specialist for Infectiology and arranging for pathogen-specific laboratory diagnostics).
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