Pneumonic Plague: Causes, Symptoms & Treatment

When thinking of the plague, the image of the Middle Ages often pops up immediately. However, there are still minor outbreaks of the disease. Pneumonic plague is the second form of plague, along with bubonic plague. While many years ago about 20 million people fell victim to the plague, today it is circa 1000 to 2000 per year.

What is pneumonic plague?

The plague is a bacterial disease. This can run very differently. In pneumonic plague, however, the course is almost always acute. If left untreated, those affected have no chance of survival. There are different forms of plague, all of which are transmitted by the same pathogen. The plague is also known as the Black Death, among other names, alluding to earlier epidemics. Plague is actually a disease of rodents. Humans, however, can become infected either directly through contact with infected animals or through human-to-human exchange. Among the different forms of plague, it is pneumonic plague that occurs least frequently, but is no less devastating. The pathogen is transmitted by droplet infection and thus comes into direct contact with the lungs. The defense system reacts too late and various symptoms occur, such as bloody sputum. If left untreated, pneumonic plague is fatal in many sufferers. If the patient is already suffering from another form of plague, the pathogen can enter the lungs through the blood and cause secondary pneumonic plague.

Causes

Pneumonic plague is caused by the bacterium Y. pestis. This has been known for 1000 years. Especially in earlier times, the plague cost many people their lives. The main reason for this was a lack of knowledge about adequate protection and treatment. Research has now shown that the bacterium occurs mainly in rodents and is transmitted to humans by fleas. Risk factors include rats or poor hygiene standards in the household. In addition, infection via humans is also possible. Accordingly, caring for a sick person also poses a risk. In western latitudes, pneumonic plague seems to have already disappeared. However, there are still outbreaks. These are usually regionally limited and have been localized, for example, in Madagascar, Congo, China, India, Peru and the southwestern United States. In Germany, however, no case of the disease has been reported for decades.

Symptoms, complaints, and signs

In pneumonic plague, the bacterium has invaded the lungs. The first symptoms usually become noticeable after a few hours. Initially, there is fever and general weakness. Serious symptoms such as abdominal pain and bloody sputum may appear as early as the second day. The pulse rises and many sufferers experience shortness of breath. Vomiting is also possible due to the strong urge to cough. Patients complain of chills, headache, blue-stained lips, and lassitude. Coughing up the mucus is felt to be very painful. As the disease progresses, pulmonary edema may develop. Overall, circulatory failure cannot be ruled out. The pathogen can be detected in sputum as well as in saliva. Thus, pneumonic plague patients pose a serious risk of infection for healthy people. The bacterium can be transmitted, for example, via droplet infection triggered by a sneeze.

Diagnosis and course of the disease

Symptoms are not always immediately attributed to pneumonic plague. Instead, the disease may be misdiagnosed as pneumonia, for example. For definitive verification, detection of the bacterium is necessary. For this purpose, samples of the mucus or blood are taken and examined accordingly in the laboratory. If pneumonic plague is not detected and treated early, the probability of death is very high. About 95 percent of those affected do not survive the disease in this case. Appropriate treatment reduces the risk to 15 percent.

Complications

Pneumonic plague is a very serious disease that, without treatment, can usually lead to death. Although it does not occur very often, it must be examined and treated by a doctor in any case. Those affected suffer primarily from fever and abdominal pain.There is a general weakness of the patient and the affected person suffers from fatigue. Likewise, shortness of breath also continues to occur, so that there is an undersupply of oxygen to the body. The affected person suffers from headaches and blue lips. Furthermore, loss of consciousness may also occur. If pneumonic plague is not treated, circulatory failure can also occur, leading to the death of the affected person. However, complications usually only occur if the disease is not treated or is misdiagnosed as pneumonia. Likewise, pneumonic plague is highly contagious, so sufferers must avoid contact with other people. Treatment of pneumonic plague can be carried out with the help of antibiotics and usually leads to a positive course of the disease. Complications do not usually occur. If treatment is successful and, above all, provided early, the life expectancy of the affected person is not reduced or limited.

When should one go to the doctor?

If symptoms such as shortness of breath or coughing suddenly become apparent, a doctor must be consulted. It is possible that there is an underlying pneumonic plague that needs to be investigated and treated if necessary. If external signs such as the characteristic blue coloration of the lips appear, an immediate visit to the doctor is necessary. At the latest, if cardiovascular complaints, headaches or fatigue occur, medical advice is required. Other warning signs that need to be investigated are bloody sputum, severe pain and a throbbing sensation in the area of the lungs. Pneumonic plague progresses very quickly and leads to serious complications such as blood poisoning and organ failure as it progresses. A rapid clarification is therefore essential, especially in the case of a concrete suspicion. For example, a doctor must be consulted if the above-mentioned symptoms occur in connection with a flea or rat bite or a trip to Asian countries. People who suffer from bubonic plague or have someone with the disease in their immediate environment are also at risk and should seek medical advice quickly. Pneumonic plague must be treated by a general practitioner or pulmonary specialist.

Treatment and therapy

Once the pathogen has been detected, the patient is isolated to protect healthy individuals from infection. The room may be entered only on the basis of specific safety instructions. Unnecessary contact is not permitted. Antibiotics are considered for the treatment of pneumonic plague. These include agents such as streptomycin, gentamycin and tetracyclines such as doxycycline or chloramphenicol. To avoid complications that negatively affect the course of the disease, treatment must begin as early as possible. A quick diagnosis can save the patient’s life. During the last plague outbreak in Madagascar, experts were able to determine that the pathogen responsible no longer reacted to the antibiotics used. The bacterium has thus become resistant. Therefore, it may be necessary to resort to another antibiotic preparation. Patients remain contagious even after therapy has begun. People suffering from pneumonic plague continue to be isolated for at least four days after first taking the antibiotic. Only then is it possible to lift the quarantine. After surviving infection, affected individuals exhibit some immunity. However, re-infection is still possible.

Outlook and prognosis

The prognosis of pneumonic plague has improved significantly compared with the last millennium. However, if left untreated, it still inevitably leads to premature death of the patient. In an advanced stage of the disease, there is also little prospect of recovery. Pathogens spread too widely within a short time and lead to a failure of the human organism to function properly. On the other hand, a good prognosis is given to people who have a healthy as well as stable immune system, have no other previous diseases and consult a doctor already in the early stages of pneumonic plague. The highly contagious disease is treated immediately by administering medication. In addition, isolation of the patient is necessary to prevent other people from being infected by the pathogens. The progress of the disease is characterized by a rapid increase in symptoms and a rapid spread of physical irregularities.Within a few hours, the intensity of the physical impairments increases. For there to be any chance of survival, the affected person must be immediately monitored and cared for by intensive medical care. Otherwise, there is little chance of improvement. If complications or intolerances to the medication administered occur, the chances of recovery are further worsened. Although various alternative medications are available thanks to medical advances, prompt action is imperative for recovery.

Prevention

There is limited prevention of pneumonic plague. Specific safety measures apply, especially in regions where the pathogen occurs. Travelers are best to avoid contact with rodents altogether. Care should be taken especially with sick and dead animals. Mosquito sprays containing DEET will prevent infection from fleas to humans. Not to be forgotten are all pets: these should be regularly cleared of fleas. In addition, unnecessary contact with diseased people should be avoided. The same applies to clothing that was near affected people and rodents.

Aftercare

Because pneumonic plague is a very serious disease, follow-up care focuses primarily on maintaining the quality of life of those affected at an appropriate level. Pneumonic plague rarely occurs but can be completely cured, so it is important to take follow-up care seriously. Affected individuals should take it easy and only cautiously return to their usual rhythm. Once the acute phase is over, sufferers are dependent on help to manage their daily lives despite persistent fatigue and general weakness. Since pneumonic plague is highly contagious, sufferers must therefore avoid contact with the outside world and family members. This significantly reduces the quality of life. Antibiotics are usually prescribed for treatment. Normally, the disease can be successfully cured. Complications do not occur. With timely treatment, the life expectancy of affected individuals is not shortened.

What you can do yourself

Pneumonic plague is a highly rare but very dangerous and, above all, highly contagious infectious disease in Western countries. Pneumonic plague must be treated by a physician as soon as possible, otherwise the risk of morbidity exceeds 90 percent. Self-help measures are indicated only to the extent that the patient can help to ensure that the disease is correctly diagnosed and that the risk to third parties is kept to a minimum. In its early stages, pneumonic plague resembles pneumonia and, because of its rare occurrence, is very often misdiagnosed, which can be life-threatening for the patient. Anyone who has traveled to a risk area shortly before the outbreak of the disease and shows symptoms typical of pneumonic plague must be sure to explicitly point this out to his or her attending physician. Risk areas predominantly include developing and emerging countries such as the Republic of Congo, Madagascar, the Chinese hinterland, parts of India and Peru. Occasionally, however, pneumonic plague is also observed in the southwestern states of the Americas. Because the disease can be transmitted by droplets and the pathogen is extremely aggressive, the patient must be isolated immediately. Home care should be discouraged for these reasons. All medical carantine regulations must be strictly adhered to. This also applies when children are affected. Parents do their offspring no favors if they endanger themselves out of excessive care or even infect other family members.