A viral infection that often causes minimal if any symptoms. When symptoms occur, most often they are flu-like. Occasionally, the virus causes inflammation of the lining around the brain and spinal cord (aseptic meningitis) and/or inflammation of the brain (encephalitis). The virus lives in wild birds. Mosquitoes get the virus after biting an infected bird. People then acquire the virus after being bitten by an infected mosquito. The risk of becoming infected is highest during the mosquito season. Efforts to decrease the mosquito population can reduce the number of infections. Most patients fully recover and death is extremely rare. The elderly and people with impaired immune systems have a higher risk of complications and death.
Description
A viral infection that often causes minimal if any symptoms. When symptoms occur, most often they are flu-like. Occasionally, the virus causes inflammation of the lining around the brain and spinal cord (aseptic meningitis) and/or inflammation of the brain (encephalitis). The virus lives in wild birds. Mosquitoes get the virus after biting an infected bird. People then acquire the virus after being bitten by an infected mosquito. The risk of becoming infected is highest during the mosquito season. Efforts to decrease the mosquito population can reduce the number of infections. Most patients fully recover and death is extremely rare. The elderly and people with impaired immune systems have a higher risk of complications and death.
Symptoms
Many have no symptoms. Symptoms may include: fever, headache, back pain, muscle aches, lack of appetite. More severe infections cause: severe headache, stiff neck, confusion, seizures, coma.
Tests
Common tests used for diagnosis and treatment
Workup:
A history and physical exam will be performed. Additional tests will be done to establish the diagnosis in patients with suspected meningitis or encephalitis. In these patients, a lumbar puncture will be done to look for white blood cells in the spinal fluid. The fluid can be sent for special testing. Serologic blood tests can confirm the diagnosis.
Tests:
Complete blood count (CBC), Comprehensive metabolic panel (CMP), CT Scan, Magnetic resonance imaging (MRI), Urinalysis (UA), X-ray
Other Specific Tests: Serologic blood tests, serologic CSF (cerebrospinal fluid) tests, viral culture, lumbar puncture
Specialists:
Internal Medicine, Pediatrics, Family Practice, Infectious Disease Medicine, Pediatric Infectious Disease Medicine
Workup:
A history and physical exam will be performed. Additional tests will be done to establish the diagnosis in patients with suspected meningitis or encephalitis. In these patients, a lumbar puncture will be done to look for white blood cells in the spinal fluid. The fluid can be sent for special testing. Serologic blood tests can confirm the diagnosis.
Tests:
Complete blood count (CBC), Comprehensive metabolic panel (CMP), CT Scan, Magnetic resonance imaging (MRI), Urinalysis (UA), X-ray
Other Specific Tests: Serologic blood tests, serologic CSF (cerebrospinal fluid) tests, viral culture, lumbar puncture
Specialists:
Internal Medicine, Pediatrics, Family Practice, Infectious Disease Medicine, Pediatric Infectious Disease Medicine
Treatment
There is no specific drug therapy available for this infection. Treatment is aimed at reducing the symptoms and supporting the patient's vital signs. Antibiotics are not helpful. There is not a vaccine for the disease.