West Nile Fever

By | June 10, 2022

West Nile fever is a mostly harmless infectious disease. Medical measures usually only serve to combat the symptoms.

What is West Nile fever?

West Nile fever is an infectious disease caused by a virus. West Nile fever owes its name to the West Nile District, which is located in Uganda, Africa. In 1937, evidence of an infection with the virus that caused West Nile fever was first demonstrated here. For bone marrow carcinosis meanings, please visit whicheverhealth.com.

Since there are no symptoms in many cases of West Nile fever, a statement on the worldwide frequency of West Nile fever is hardly possible. However, West Nile fever occurs primarily in warm climates such as parts of Africa, India or Southeast Asia. In addition, during the summer months of 2002, an epidemic of West Nile fever also broke out in North America.

In humans, infection with West Nile fever is not subject to reporting. However, if animals are infected with the virus that causes West Nile fever, there is an animal disease that must be reported.


West Nile fever is caused by an infection with the so-called West Nile virus (WNV). The virus that causes West Nile fever is transmitted by insects, especially mosquitoes.

Since West Nile fever is transmitted from animals to humans, the viral infection is called zoonosis : Wild birds are often first affected by West Nile fever; Mosquitoes that have had contact with animals infected with West Nile fever can then transmit the virus to humans.

West Nile fever can also be caused by an infection that occurs from person to person: Such transmission can occur, for example, during organ transplantation or blood transfusions. It is also possible that the virus responsible for West Nile fever can be transmitted from breastfeeding mothers to their infants.

Typical Symptoms & Signs

  • Fever
  • headache
  • body aches
  • Diarrhea
  • nausea
  • Vomit
  • lymph node swelling
  • skin rash

Diagnosis & History

West Nile fever is difficult to diagnose based on symptoms. This is partly due to the fact that possible symptoms are non-specific and West Nile fever is often completely symptom-free.

A reliable diagnosis of West Nile fever is therefore primarily possible with the help of blood samples : the pathogen is usually detectable in the blood of those affected who are infected with West Nile fever. Antibodies that form in the blood or cerebrospinal fluid in the presence of West Nile fever also enable a diagnosis to be made.

The incubation period for West Nile fever is usually a few days. If West Nile fever is associated with symptoms, these are usually similar to those of mild flu. West Nile fever is then predominantly self-limiting; this means that the symptoms resolve on their own within a few days.

In a clear majority of those affected, the West Nile flu runs without complications. Risk factors for the occurrence of complications from West Nile fever are, for example, other physical illnesses or old age.


In most cases, West Nile fever is unproblematic and subsides after about seven days. Certain factors play a role in the course of the disease, such as the age of the patient, the immune system, physical illnesses and psychological factors. Complications are rather rare and when they do occur, they mostly affect elderly or immunocompromised people.

These people can develop heart muscle inflammation, meningitis or paralysis. If the course is severe, it makes sense for the patient to be treated as an inpatient so that the course can be better monitored. This particularly affects older people or people with an immune deficiency because the disease can be life-threatening for them.

Death is rare, but some patients have long-term sequelae after recovery, especially if the brain has also been affected. But even people with an unproblematic course can still suffer from body aches, concentration and memory problems and fatigue months after West Nile fever.

When should you go to the doctor?

If a stay abroad is planned, it is generally advisable to obtain sufficient information about the conditions there. The person concerned should build up knowledge about the health risks and, if necessary, consult the doctor treating them. The hygiene conditions must be found out in good time and the probability of certain diseases should be inquired about. In some cases, vaccinations are recommended so that the organism can adequately defend itself against the pathogens.

West Nile fever only occurs in people who are in Africa, Southeast Asia or India. For this reason, it is advisable to take appropriate health precautions before traveling to this region. In principle, however, there is no increased risk of a serious illness with the infectious disease. Nevertheless, a doctor should be consulted as soon as health impairments become apparent. If you have a fever, headache, disorders of the digestive tract or swelling of the lymph, it is advisable to consult a doctor.

A feeling of illness, general malaise, nausea and vomiting indicate a medical condition that should be diagnosed and treated. Changes in the complexion, irregular movements and an increase in existing symptoms must be discussed with a doctor. Medical treatment is necessary so that the symptoms can be alleviated as quickly as possible. Itching and swelling of the skin should also be evaluated by a doctor.

Treatment & Therapy

In the majority of cases, West Nile fever does not require medical treatment. Healing usually takes place within a few days. If the West Nile fever is accompanied by severe symptoms, a sensible measure can be, among other things, that the person concerned goes to bed rest.

Accompanying this, in the case of severe West Nile fever, in consultation with the doctor treating you, symptoms that occur can be alleviated; appropriate measures may include, for example, lowering the fever and/or adequate fluid intake.

Only in very rare cases of West Nile fever is specialist care necessary as part of a hospital stay; Such a step can make sense, for example, if there is a greatly increased risk of complications in connection with West Nile fever (such as the risk of suffering inflammation of the brain or heart).

Targeted drug preparations to combat West Nile fever are currently not available to medicine.


West Nile fever can only be prevented to a limited extent, as there are still no vaccines that can be used in humans against West Nile fever. Measures that can serve as individual prophylaxis against West Nile fever are aimed at avoiding mosquito bites in areas affected by West Nile fever: it can be useful to apply anti-mosquito sprays. And wearing long clothes can also help to avoid mosquito bites and thus West Nile fever.


Aftercare for West Nile fever is based on the symptoms that the patient shows and the course of the disease. If the course is positive, the symptoms subside within three to fourteen days. The patient must then visit the doctor again, who will carry out a routine examination.

In addition, a clarification of the symptoms is necessary. The medication with antibiotics can then be tapered off. An anamnesis is also taken as part of the aftercare. Measures must also be taken to prevent re-infection. If the symptoms occur after a trip abroad, any fellow travelers should also be examined.

The same applies to family members who have had contact with the sick person. The therapy itself ends after seven days. It is limited to alleviating the symptoms with rest and sufficient sleep. The treatment and aftercare should take place as an inpatient in a hospital so that complications can be dealt with quickly.

Follow-up care is provided by the responsible internist or family doctor. If the course is severe, other specialists must be consulted. If permanent damage is to be expected, psychological care for the patient is often necessary.

You can do that yourself

The flu-like symptoms of West Nile fever usually go away within a week, even without treatment. In order for the body to be able to fight the infection successfully, it needs a lot of rest: Sick people should take it easy during this time and avoid sports and heavy physical work. Light, vitamin-rich food supports the immune system, stomach-friendly foods such as rusks, oatmeal or a vegetable mash made from boiled carrots and potatoes help with nausea and vomiting. In herbal medicine, ginger is successfully used as a spice, tea or in the form of capsules from the pharmacy to combat nausea. Fever can be treated with simple home remedies such as calf wrapslower, but should be avoided if you have chills.

A lot of fluid is lost through heavy sweating: Sufficient fluid intake is extremely important to prevent circulatory disorders. Unsweetened herbal teas or a lightly salted chicken broth are best suited for this. Linden blossom and elderflower tea are known for their antiperspirant and anti-inflammatory effects, while willow bark tea can relieve pain.

If the symptoms do not improve within a week or if there are additional symptoms of the onset of meningitis (severe headache, photophobia, stiff neck), you should refrain from further self-treatment and consult a doctor immediately. Consistent protection against mosquito bites in endangered regions with insect repellent and appropriate clothing is recommended as a preventive measure.

West Nile Fever