Years from now, when we consider all the stresses of the season—affordable healthcare, swine flu, global strife, etc.—we’ll have a good reason to call it our winter of discontent. With all this uncertainty afoot, it may be smart to take a hard look at viral encephalitis, a serious medical condition that has the potential to become more widespread, especially when one considers its history and connection to global epidemics. Its link to viruses transmitted by mosquitoes and ticks makes it a downright scary symptom of a modern world where no one is immune to global disease, pestilence and man-made threats.
Doctors know surprisingly little about the exact cause of encephalitis. What they do know is that the brain swells when too many white cells overreact to a bacteria or a virus that has invaded the body. Several thousand cases of encephalitis are reported in the U.S. each year. But those numbers actually may be higher, since swelling of the brain may go unnoticed in persons recovering from a viral illness.
A majority of cases in this country are thought to be secondary encephalitis or post-infectious encephalomyelitis (swelling of the brain, optic nerves and spinal cord). But they’re no less dangerous than primary encephalitis, where an infection from a tick or mosquito bite goes directly to the brain.
In adults, secondary encephalitis can be a complication of mononucleosis, the flu, cold sores, shingles, cancer or AIDS. Bacteria-related causes can be as diverse as Lyme disease and tuberculosis. In kids, it can follow a bout of measles, mumps or chickenpox—all the more reason for parents to be vigilant about immunizations.
Just knowing the symptoms of encephalitis could save your child’s life. Andro Zangaladze, a neurologist with Thomas Jefferson University Hospital, estimates that 5-10 percent of the young patients he sees have seizures due to encephalitis—particularly the type known as secondary encephalitis. It affects a disproportionate number of school-aged children who’ve either just recovered from one of the viruses mentioned or, in rare cases, are suffering from bacterial meningitis or other infection. A third scenario—even more rare, but worth a mention—is encephalitis due to an allergic reaction to an immunization.
Secondary encephalitis is labeled as such because it’s the result of an earlier viral infection that might mask symptoms. By way of an example, 90 percent of those with secondary encephalitis or post-infectious encephalomyelitis have flu-like symptoms such as fever, sore throat, coughing and malaise. “The bottom line is that, if your child is experiencing these [flu-like] symptoms but also has a fever, stiff neck, headaches, light sensitivity and confusion, you should take them to the emergency room right away—without question,” says Zangaladze.
By the time patients start experiencing confusion or disorientation—two important warning signs that it’s not just the flu—brain tissue may have become so inflamed that they’re in danger of a hemorrhage, an aneurysm, or convulsions and epileptic-like seizures. Potential internal bleeding and damage to the central nervous system are two reasons why patients with even mild forms of encephalitis are carefully monitored for changes in blood pressure, heart rate and breathing.
Most people fully recover from viral encephalitis. But it’s also unpredictable, and treatment is limited. Antibiotics aren’t effective against viruses (with the exception of herpes simplex, which causes cold sores), and antiviral medications are too virus specific. Encephalitis can’t be prevented—only avoided through immunization and preventative measures like washing your hands, staying away from those who are ill, and avoiding situations in which exposure to viruses, bacteria, mosquitoes, ticks and parasites might easily occur.
The Centers for Disease Control and the World Health Organization closely monitor outbreaks of encephalitis, as they generally point to viral neuroinvasive and pathogenic events. It’s been more than a decade since the West Nile virus caused a nationwide scare and several people in the New York area died of encephalitis. More recently, the mosquito-transmitted Eastern equine encephalitis has been in the news, though cases have mostly affected horses.
With many of Zangaladze’s patients, the encephalitis has already reached the stage where permanent neurological damage is possible. That’s because the body’s cellular response has gone into overdrive, attacking the protective coating around the brain and nerve cells.
The resulting damage can lead to the sort of problems associated with stroke victims, including impaired speech, hearing and muscle control. There’s also the chance of future learning disabilities and memory loss.
And for young patients with growing brains, any damage due to intracranial pressure could mean seizures down the line. “I have to break the bad news,” says Zangaladze. “I tell them that they’re probably going to be on medication for some time.”
1. It’s most often caused by a viral infection and is rarely life threatening. But since there are so many types of viruses, the disorder is unlikely to go away anytime soon.
2. While there are no antiviral drugs or specific treatments, mild cases can be treated at home with antibiotics (in bacteria-related cases) and Tylenol (to reduce fevers).
3. Several thousand U.S. cases are reported yearly, but experts suspect that many more mild cases go undetected.
4. It can be caused by common bacterial infections, including cold sores and walking pneumonia.
5. Recent cases in the U.S. involved children who’d recovered from pneumonia or meningitis.
6. Though it’s not contagious, families are advised to isolate patients, since the viral causes may not be known.
7. The acute phase generally lasts for one to two weeks, but outcomes vary widely. Symptoms may suddenly disappear, or complications could require months of speech or physical therapy.
If you or a loved one experiences any of the following, seek immediate medical attention:
• A severe headache that won’t go away
• Sensitivity to bright light or double vision
• Sudden changes in personality, including irritability, indecisiveness, extreme self-centeredness and withdrawal from social interaction
• Flu-like symptoms—including high fever and a stiff neck—accompanied by “brain fog” or extreme lethargy
• Problems with speech or hearing
• Loss of sensation anywhere in the body, or difficulty moving an arm or leg
Infants younger than 1 year are more likely to die from encephalitis, as mild cases are difficult to detect. Look for fullness or bulging in the head’s soft spot, or any of the following:
• Poor appetite and reduced feeding
• Body stiffness or floppiness
• Crying that’s weak or reduced in volume