Lassa fever

The Lassa fever is a viral disease that occurs preferentially in only some parts of West Africa. The countries affected are Nigeria, Ivory Coast and Guinea, among others. So far, only isolated diseases have occurred in Germany. If Lassa fever is found, there is an obligation to report.

What is Lassa fever?

The Lassa fever is a viral hemorrhagic fever (associated with internal bleeding), which also includes Ebola, yellow fever and the Marburg virus infection. According to an international agreement, the fever was named after the place Lassa, where it was first detected.

It is caused by viruses and initially runs like the flu. The person concerned suffers from fever, headache and body aches, later sore throat, dry cough, chest pain and cramps in the stomach. The first symptoms appear after 6 to 21 days of incubation.

In many cases the sick suffer from mild symptoms and not in every single case there is internal bleeding. Nevertheless, the rate of fatal disease is around ten to 20 percent, and pregnant women even 50 percent.

causes

The cause of the Lassa fever is the Lassa virus that is transmitted by the African multi-teat rat. The virus gets through the excretions of rats (feces or urine) on food and from there into the human organism.

In some areas, the rats are eaten themselves and transmit the virus directly. The rat itself does not show any symptoms of the disease. Lassa fever can also be transmitted from person to person through droplet infection.

Contact with the blood, saliva, semen, vomit, urine or feces of a sick person are also possible causes of infection.

Lassa fever occurs where a lack of hygienic conditions makes it an ideal breeding ground for food contamination or the transmission of Vitus from person to person.

Symptoms, ailments & signs

Lassa fever often causes no or only imperceptible symptoms. In two out of ten cases, the illness is associated with flu symptoms, such as fever, muscle, headache and joint pain, and fatigue. After five to seven days, symptoms of the respiratory tract appear.

These include cough, severe sore throat and swelling in the larynx area, but also inflammation of the pharynx and tonsils. White or yellowish deposits then form on the tonsils and give off an unpleasant odor. Possible accompanying symptoms of Lassa fever are chest pain and stabbing headache.

In addition, hemorrhagic fever can cause blood pressure fluctuations and occasionally lead to circulatory failure. If the pathogen is spread, there is a risk that the internal organs will become inflamed. Then conjunctivitis with internal bleeding or pericarditis develops. Edema can occur in the area of ​​the eyelids and neck.

This accumulation of water is usually associated with further pain and severe discomfort, and mobility is often restricted. Lassa fever can also cause gastrointestinal complaints such as nausea, vomiting and abdominal cramps. The symptoms mentioned appear insidious and quickly subside with expert treatment. Eight out of ten patients can expect the disease to develop mildly without serious symptoms or discomfort.

Diagnosis & course

The Lassa fever can be clearly diagnosed by detecting the causative virus in the blood, urine, throat or tissue samples of the sick person. The specific antibodies against the virus can be detected in the blood about a week after the onset of Lassa fever.

In order to achieve a good prognosis and to exclude late symptoms as far as possible, a blood test should be arranged as soon as possible if there is a suspicion. Because of the symptoms, especially in the early stages, conclusions are often drawn about other diseases. Lassa fever initially shows flu-like symptoms, so that a severe flu infection can be assumed.

Confusion with malaria or other haemorrhagic fevers is also possible. The typical symptoms of Lassa fever include edema of the face, conjunctivitis, protein excretion in the urine, sore throat and pain behind the breastbone.

In the event of a severe course of the disease, bleeding of the internal organs, the mucous membranes and the skin ultimately occurs, which can result in a failure of the cardiovascular system.

Complications

Because of Lassa fever, people suffer from the usual symptoms of flu. This leads to a strong and high fever and furthermore to aching limbs. The patient's resilience also decreases significantly due to the illness, so that fatigue and exhaustion occur. This disease also leads to a sore throat and headache.

It is not uncommon for patients to experience pain in the abdomen or vomiting due to Lassa fever. In many cases, the disease can also be mistaken for malaria, so that treatment of these symptoms is delayed. If Lassa fever is not treated, the patient may die. The treatment itself is carried out with the help of medication and usually quickly leads to success.

There are no particular complications, so that a positive course of the disease can be recorded. The patient's life expectancy is not reduced if treatment is started early. Furthermore, there are no particular complications or complaints. However, those affected are not allowed to maintain contact with other people, as Lassa fever has a high risk of infection.

When should you go to the doctor?

People who develop flu after a stay in a country with poor hygienic conditions should consult their family doctor. If you add a cough, sore throat, and other signs of Lassa fever, seek medical advice immediately. The symptoms indicate a serious illness that must be clarified by a doctor in any case. If there is stabbing chest pain or headache, the person concerned must be taken to hospital.

In the event of circulatory failure, severe blood pressure fluctuations and other typical complications, the emergency doctor must be alerted. The affected person should take care of himself, in case of doubt first aid measures must be taken. Lassa fever is treated by the family doctor or an internist. Depending on the symptoms, cardiologists, ophthalmologists or gastroenterologists must be consulted. People who suffer from a chronic illness or allergy are best advised to confer with the responsible doctor. If a child shows symptoms of Lassa fever, parents should call emergency services. Pregnant women and seriously ill people also need to have unusual complaints clarified immediately.

Treatment & Therapy

Lassa fever is treated by inhibiting the virus from multiplying as far as possible and relieving the patient's symptoms. In addition, the affected person must be given sufficient fluids. Intensive care care is often required because of the possibility of sudden hypotension (low blood pressure).

Patients are given the active substance ribavirin to help contain the virus. In Lassa fever, a quick diagnosis and starting treatment within six days of the onset of symptoms is an important factor in the prognosis.

The way in which the medication is administered also plays a decisive role. The mortality rate drops by a factor of three with early start of treatment and oral (by mouth) administration of ribavirin, and with intravenous administration even by a factor of 10.

Outlook & forecast

Most people have mild Lassa fever. You recover completely. A good 20 percent perceive no complaints at all. With all others, the typical symptoms appear with varying degrees of intensity. From the second week of the illness, a clear improvement begins. The death rate is around one to two percent based on all infections. It is noticeable that most of those affected die around the twelfth day of illness. The failure of the kidneys and the circulatory system play an important role here. Bleeding can also occur.

Lassa fever is native to the African continent. There it is found in Nigeria, Guinea, Liberia and Sierra Leone. There are hardly any diseases in industrialized countries like Germany. The virus was imported unnoticed in individual cases.

Due to the risk of infection, patients must take precautionary measures towards other people. While the disease phase lasts a maximum of four weeks, viruses with a contagious potential can sometimes be detected in the excretion for ten weeks. Transmission is also possible via blood and saliva. If the Lassa fever goes badly, the time for recovery will drag on. Patients then suffer from numbness and disorders of the musculoskeletal system. An early start of therapy is considered to be the most effective remedy for Lassa fever.

prevention

Contagion with that Lassa fever can be prevented by avoiding contact with rats and people who are already ill and by ensuring adequate hygiene. Lassa viruses can be excreted in the urine for up to nine weeks and in the seminal fluid for up to three months after the onset of the disease and lead to infection. Antibodies are formed against Lassa fever, which rule out a new disease.

Aftercare

The follow-up care measures for Lassa fever are often severely limited. Those affected are primarily dependent on rapid and, above all, immediate treatment of the symptoms so that no further complications can arise. Self-healing of the disease is usually not possible, so that the person affected should consult a doctor at the first signs and symptoms of the fever.

Usually, the infection is treated by taking various drugs. It is important to ensure that it is taken regularly with the correct dosage in order to permanently alleviate and limit the symptoms. If you have any questions or are unclear, you should always consult a doctor first. Consult a doctor first if the medication has side effects.

Most patients are dependent on the help and care of other people during the treatment of Lassa fever, whereby the care provided by their own family can have a positive effect on the further course of the disease. This can also prevent depression or other psychological upsets. Lassa fever may reduce the life expectancy of the person affected, although the further course of the disease depends heavily on the time of diagnosis.

You can do that yourself

Lassa fever is a highly contagious and therefore reportable disease. In addition, the disorder is very dangerous and can be fatal. The risk is particularly high for pregnant women, in this group the morbidity is even 50 percent if the disease is not treated professionally immediately.

The best self-help measures that the patient can take is therefore prevention and the immediate consultation of a doctor if an infection is suspected. Lassa fever occurs almost exclusively in West Africa. The virus that causes the disease is transmitted by rats. Therefore, under no circumstances should rat meat be eaten. Since the animals spread the virus through other means, such as their droppings, raw foods should also not be consumed. For fruit, nuts are preferred. It can also be transmitted from person to person through droplet infection. Contact with the saliva or semen of infected people is particularly dangerous.

The incubation period is between a few days and up to three weeks. Anyone who shows symptoms of flu during a stay or shortly after returning from a risk area should immediately consult a doctor and explicitly point out the possible infection with Lassa fever, so that the suspicion can be clarified immediately and adequate treatment can be started promptly.