Japanese Encephalitis

According to fun-wiki.com, Japanese encephalitis is an infectious disease caused by viruses. It is most common in Southeast Asia, China and India and can be fatal if left untreated. However, there is a vaccination against this tropical disease that the Tropical Institute recommends to every traveler to Asia. Young children and the elderly in particular are at risk of serious complications from Japanese encephalitis.

Japanese Encephalitis

What is Japanese Encephalitis?

Cases in which the symptoms are severe and begin with a high fever, headache and muscle pain are of concern. Within a few hours and days after the first symptoms of the disease, disturbances of consciousness occur, which indicate the involvement of the meninges.

Japanese encephalitis is a tropical disease that occurs primarily in East and South Asia. Most of India and the southern part of the People’s Republic of China are badly affected. It is a viral disease that causes very mild symptoms in many cases or can remain symptom-free because it does not break out at all.

However, one in 250 people becomes seriously ill and develops encephalitis, i.e. inflammation of the meninges. It is accompanied by symptoms such as impaired consciousness, high fever, muscle pain and severe headaches. Diarrhea and vomiting are also characteristic of children. When Japanese encephalitis is not fatal, it often leaves permanent damage.


Japanese encephalitis is caused by viruses that live in livestock. Birds and pigs living in the wild are particularly suitable as they carry the most viruses. Occasionally they are also found in horses or bats. They are ultimately transmitted by mosquitoes, which pick up the virus from livestock and insert it into humans by biting them.

The incubation period of Japanese encephalitis virus is 5-15 days, after which Japanese encephalitis can break out. The risk of infection for tourists is very low; the rural population in the endangered areas is primarily affected. The rate of new Japanese encephalitis infections is also related to the mosquito life cycle and rainy seasons, which are critical to the survival and death of vector animals in this zone of the world.

Symptoms, Ailments & Signs

Japanese encephalitis is usually mild or causes little or no symptoms. In two out of 250 cases, however, those infected develop severe health problems that are fatal in almost 30 percent of cases. Many survivors suffer permanent neurological damage after recovery.

Generally, Japanese encephalitis produces flu-like symptoms with fever, chills, and headache. If the course is severe, meningitis sets in, which, in addition to fever, also causes headaches, muscle and neck pain, neck stiffness and exhaustion. Gastrointestinal complaints and increased sensitivity to light and noise are also typical.

If there is also encephalitis, the initially high fever is followed by symptoms of failure of the nervous system. Many patients experience confusion, decreased consciousness, and changes in behavior. Physically, brain inflammation manifests itself in the form of seizures, paralysis, reflex disturbances and muscle tremors.

In the further course the patient falls into a coma. Symptoms of severe Japanese encephalitis come on quickly and get worse over a few days. The fever usually only goes down again after seven to ten days of illness. If the course is severe, the individual symptoms can lead to the death of the patient.

course of the disease

Following infection, Japanese encephalitis virus is killed by the body’s immune system in most cases. The disease does not develop and the person does not suffer any permanent damage. After the incubation period of 5-15 days, only very mild symptoms can occur, which would hardly differ from a severe flu . They disappear on their own after a few days and weeks and also leave no damage behind.

Cases in which the symptoms are severe and begin with a high fever, headache and muscle pain are of concern. Within a few hours and days after the first symptoms of the disease, disturbances of consciousness occur, which indicate the involvement of the meninges. Other neurological symptoms may also develop.

If left untreated, Japanese encephalitis can be fatal. Even with treatment, this can sometimes be the case. At best, the patient survives Japanese encephalitis with only some permanent damage.


This encephalitis is a very serious disease. If there is no treatment, the patient can die from this disease in the worst case. Irreversible consequential damage is also possible. In order to avoid possible discomfort and complications, vaccination should always be carried out before a trip.

Those affected suffer from a high fever and headaches. These can also spread to other regions of the body and cause pain there. Furthermore, if left untreated, there will be severe paralysis all over the body and a stiff neck. Complete unconsciousness may also occur and the sufferer may suffer from a stiff neck.

The quality of life is significantly reduced by Japanese encephalitis and everyday life is restricted. The resilience of those affected also decreases significantly as a result of this disease. Japanese encephalitis cannot be treated directly. Only the complaints are restricted.

There are no particular complications. However, the duration of this infection cannot be predicted. It is also possible that the affected person is infected again even after successful treatment. If treatment is started early, there is usually no reduction in life expectancy.

When should you go to the doctor?

If you notice any abnormalities and changes in your health a few days after receiving a mosquito bite, you should consult a doctor. Any skin changes, unusual wound formation, or peculiarities of the lymph should be a cause for concern. A doctor should be consulted as soon as you feel unwell, have an inner weakness or feel ill. If symptoms similar to those of the flu are noticed, these should be observed.

If you have a headache, an increased need for sleep, fever or sweating, you should consult a doctor. Fatigue and a lack of concentration as well as loss of appetite must be examined and treated. If neurological abnormalities occur a short time later, medical care must be initiated immediately. In the case of unsteady gait, memory problems or functional disorders, the person concerned needs medical help. A doctor’s visit is imperative, as it can lead to permanent impairments and a reduced quality of life.

Any trembling limbs, muscle weakness, body stiffness or general inefficiency should be evaluated and treated. Paralysis and cramps already indicate a strong progression of the disease. To avoid long-term damage, a doctor’s visit is necessary. In severe cases, without medical treatment, the affected person may die prematurely. In acute cases, an emergency service must be alerted. Until it arrives, first aid measures must be taken.

Treatment & Therapy

Currently, Japanese encephalitis cannot be specifically treated. Since the virus is involved, research into an active substance is also made more difficult, since it is not a question of bacteria and classic methods (eg antibiotics) are therefore hardly effective. In the case of Japanese encephalitis, the course of the disease is primarily treated symptomatically. For example, it is possible to use medication to lower the patient’s fever to prevent it from causing permanent damage or dying of the patient.

It also supports breathing and circulation, which may be affected by brain involvement. It may also be useful to prevent secondary infection by isolating the patient, as this could be fatal.


Comprehensive care and follow-up care is required to completely cure Japanese encephalitis. Treatment is aimed at relieving symptoms. Correct intake of the medication prescribed by the doctor is very important for the patients. So far there are no drugs for the direct treatment of the disease, but those affected should consult a doctor.

Self-medication at home carries the risk of complications. A specialist doctor, on the other hand, can identify the risk at an early stage and do something about it. As part of a targeted, intensive therapy, the disease can be cured with timely intervention. Treatment is generally inpatient to ensure close monitoring.

After therapy, follow-up care focuses on further check-ups. Even after the hospital stay, those affected should still take it easy. In order to rule out secondary infections, meticulous hygiene must be observed. This includes the use of disinfectants. Certain safety measures are designed to protect patients from contamination during the recovery phase.

Only when the symptoms of the disease have receded due to the regular intake of the medication can those affected give up their isolation caused by the disease. However, depending on the severity of the life-threatening illness, the recovery phase may take a little longer.

Outlook & Forecast

Japanese encephalitis can lead to numerous complications and premature death without adequate medical care. Although the infectious disease mostly occurs in Southeast Asia or India, it can still be transmitted to the local population by vacationers or other travelers. Due to the drastic course of the disease, there is the possibility of a vaccination. Since almost 30 percent of those who are ill are confronted with a fatal course, this should be used in the event of a planned trip. If vaccination has taken place, an infection and thus an outbreak of the disease is unlikely.

The difficulty of Japanese encephalitis lies in the risk of confusion with an influenza disease. If the diagnosis and thus the medical treatment are carried out at an advanced stage of the disease, the prognosis worsens. It can lead to lifelong consequential damage such as restricted mobility, paralysis or headaches. There is also the possibility of loss of consciousness. In the case of disorders of consciousness, intensive medical care is necessary. Brain lesions are possible that are irreversible.

With prompt and comprehensive medical care for the patient, there is a chance of a full recovery. A symptomatic treatment takes place, which is created according to the individual complaints of the patient. Medication is used to reduce the symptoms.

You can do that yourself

While there are still no effective drugs to treat Japanese encephalitis, sufferers should under no circumstances attempt to self-monitor the disease at home. Professional medical therapy and care are essential to respond adequately to potentially serious complications. Patients with Japanese encephalitis go to inpatient care and follow the instructions of the doctors and staff. In the absence of suitable medication, the nursing staff only monitors the vital functions of the body, such as the patient’s circulation, heart rate and breathing.

The affected person spends most of the inpatient stay in a resting position and takes hygienic and quarantine measures to ensure that they do not contract secondary infections. Contact with other people is only possible if they have undergone thorough disinfection and appropriate safety measures are in place.

During inpatient treatment, the patient must ensure that he or she is getting enough energy and nutrients through their diet . If adequate food intake is not possible due to physical weakness or other reasons, the patient is given liquid nutrition intravenously. The patient must inform the medical staff of any change in his or her condition in order to avoid complications of Japanese encephalitis.