Encephalitis literally means an acute inflammation of the brain. Normally virus causes Encephalitis, but other things, together with bacteria, may also be responsible. Even though encephalitis seems intimidating, the majority of cases aren’t so severe. The severe and potentially acute form of this disease is unusual. Encephalitis is a rare form of disease that occurs in about 0.5 per 100,000 individuals. It is common in children, the elderly, and people with destabilized immune system; especially those suffering from HIV/AIDS or Cancer.
Encephalitis appears in 2 forms —
- Primary form
- Secondary form
Primary encephalitis: It includes direct viral infection of your brain and spinal cord.
Secondary encephalitis: It is a viral infection that primarily takes place somewhere else in your body and then attacks your brain.
The result of the disease varies depending on factors like age, severity of the case, and strength of the immune system. As is said before, people having HIV, cancer, or other diseases possess weaker immunity and are less capable of resisting another disease. Generally, those suffering from mild cases will bring round hardly facing any troubles.
It can’t be denied that the death rate for viral encephalitis can be alarming.
The St. Louis encephalitis virus can bring about death in up to 30% of the cases.
Japanese encephalitis can be responsible for death in up to 60% of the cases, generally within the first week of the disease.
If the herpes encephalitis is kept untreated, 50-75% of people die within 18 months. Acyclovir (Zovirax) can augment survival up to 90%.
The signs and symptoms of encephalitis are similar to the adults and children.
Signs and symptoms which are flu-like in nature, may persist for 2-3 weeks, and can comprise 1 or more of the following:
- Sore throat
- Rigid neck and back
- Unsteady gait
- Visual sensitivity to light
More severe cases may include following signs and symptoms:
- Muscle weakness
- Loss of memory
- Sudden impaired judgment
- Poor responsiveness
It is difficult to spot some of the signs and symptoms in kid. But it is necessary to detect these symptoms. The symptoms include:
- A full or bulging soft spot
- Nonstop crying that seems worse as an infant is picked up
- Stiffness of body
Encephalitis can be caused by various types of germs and the infection can be spread in various ways. But it generally occurs due to 3 different groups of viruses. The list of these viruses include: herpes viruses along with chickenpox, EBV (Epstein-Barr virus — the virus that causes mono), and herpes simplex (the virus that causes cold sores).
One of the most hazardous and most known causes of encephalitis includes herpes simplex virus (HSV). It is the same virus accountable for cold sores around the mouth, but if it attacks the brain it may seldom be fatal. Luckily, HSV encephalitis is quite uncommon.
Cold sores and lesions of the genitals are caused by this virus. This virus is transmitted plainly through human contact. Newborns can also become infected with the virus while passing through an infected birth canal. Once the virus enters the body, it traverses through nerve fibers causing an infection of the brain. The virus may also experience a latent period in which it remains dormant. Later on, emotional or physical stress can reactivate the virus causing a brain infection.
This herpes virus causes infectious mononucleosis (mono). If encephalitis occurs, it’s generally mild in nature, but can be fatal in a few of cases.
Hosts of such virus are animals for example birds, pigs, chipmunks, and squirrels that bear the virus.
Mosquitoes which are known as vectors or medium of transmitting the virus feed on these animals and become infected. The virus, in this way, develops and cycles between the hosts and the vectors and consequently humans get infected through mosquito bites. Once the virus goes inside the body, it replicates and progresses through the bloodstream. If there is huge amount of the virus present, the brain can be infected. The majority of cases take place between June and September when the mosquitoes remain heavily active. In warmer climates, the disease can happen year-round. But this sort of encephalitis is quite infrequent.
Chickenpox and shingles occur just because of this kind of virus. It may encourage encephalitis in adults and children, but tends to be mild in nature.
West Nile virus: Mosquitoes are also able to transmit the viruses for several types of encephalitis, including West Nile encephalitis, St. Louis encephalitis, and Western Equine encephalitis. Over the last several years in the United States, people are worried about the spread of West Nile virus, transmitted to humans by mosquitoes that collect the virus by biting infected birds. The WNV was considered a cause for severe inflammation of the spinal cord and brain in humans. West Nile encephalitis is neither transmitted from person to person through touching or kissing or from a health care giver caring for a sick person, nor can it be transmitted to human from animals.
Eastern equine encephalitis: This infection is generally common among horses and birds, particularly birds that live close to freshwater marshes. It can also tell upon humans, although less than 10 cases are reported in most years.
Western equine encephalitis: Majority of the reports of western equine encephalitis come from the central and western Plains of the United States. Similar to eastern equine encephalitis, this infection afflicts horses and, seldom, humans. It is highly found in birds that reside near irrigated fields and farming parts. Symptoms come into view between 5 and 10 days after a bite. Western equine encephalitis is less likely to be life threatening than is its eastern cousin, but can cause brain damage and other severe difficulties, particularly in infants.
La Crosse encephalitis: This virus is given name for La Crosse, Wis., where the virus was first identified in 1963. It’s found mostly in the hardwood forest areas of the Upper Midwest and in Appalachia. In contrast to other forms of viral encephalitis, this virus is transmitted to mosquitoes from chipmunks and squirrels. La Crosse encephalitis normally has an effect on children and is hardly ever fatal. In general, less than 100 cases of the disease are reported yearly. Symptoms emerge 5 to 15 days after receiving a bite from an infected mosquito.
Seldom, encephalitis can happen due to a bacterial infection, such as bacterial meningitis, or it can be a complication of other infectious diseases like syphilis. Certain parasites, such as toxoplasmosis, can also bring about encephalitis in people with undermined immune systems.
Is It Contagious?
Infection with various viruses can cause encephalitis. So how infectious the disease is depends on the type of virus. Viruses such as West Nile are only passed on through the bite of already infected insects but it’s impossible to have them from other people. But viruses such as EBV are transmitted from person to person.
Although a person becomes infected by virus causing encephalitis, it does not denote that person will automatically have the condition. Actually, very few of the people who are infected with these viruses develop encephalitis in reality.
In order to diagnose encephalitis, the doctor may collect blood samples and order a spinal tap (also called a lumbar puncture), a process in which a very thin needle is inserted into the lower back in order to eliminate some Cerebro Spinal Fluid (CSF) surrounding the brain and spinal cord. The samples will be sent to a laboratory to detect viruses or bacteria.
A special brain scan (an MRI or a CT scan) may also be recommended to detect any kind of inflammation. The doctor might also order an Electro Encephalo Gram (EEG), a test that keeps track of your brain waves and can disclose any abnormalities consistent with encephalitis.
A DNA study known as Polymerase Chain Reaction (PCR) has tremendously improved the analysis of herpes encephalitis.
Brain biopsy: It is optional even though it is seldom performed and in case the other tests fail.
Blood testing: Your doctor can confirm the presence of West Nile virus in your body by sending the sample of your blood for laboratory test. If you have West Nile virus, an examination of your blood sample may confirm an increasing level of an antibody to the virus, a positive DNA test for the virus or a positive culture of the virus.
Treatment for mild cases mainly includes:
- A healthy diet, including plenty of liquids
- Use of acetaminophen (Tylenol, others) in order to relieve headaches and fever
The vaccine is available to prevent only Japanese encephalitis.
Nonetheless, some viruses, especially the herpes simplex virus and varicella-zoster virus, respond to antiviral drugs such as acyclovir (Zovirax). If you experience one of these kinds of virus-induced encephalitis, your doctor will possibly start treatment with acyclovir right away. Another antiviral which is sometimes used is ganciclovir (Cytovene). Apart from herpes encephalitis, the mainstay of treatment is devoid of any kinds of symptom. People having encephalitis are kept hydrated with IV fluids at the time of examining brain swelling. Anticonvulsants can be prescribed in order to control seizure. Steroids have not been considered as being useful.
Along with antiviral medications, your doctor may also treat you with the following:
- Anti-inflammatory drugs, like corticosteroids, in order to help decrease swelling and pressure within your skull.
- Anticonvulsant medications in order to stop or prevent seizures.
- Following the illness, you may also feel the need of undergoing physical and speech therapy.
At present, the use of ribavirin (Rebetol, Virazole) to treat a child with La Crosse encephalitis is being revised.
The best possible way to avert encephalitis is to keep away from getting infected with the viruses or other germs that can cause the disease. Daily hand washing will help check the spread of some of these germs. Stay as healthy as possible by eating a balanced diet and taking adequate rest. This can help develop your immune system. Immunization is vital to protect people from diseases, such as chickenpox and measles.
Give protection to yourself by wearing long sleeves and pants and applying an insect repellent in places where viruses are passed on by insect bites. Also, try to stay away from irrelevant outdoor activities at dawn and dusk when the prevalence of mosquitoes is high.
Avoid water sources outside your home. Get rid off stagnant water in your yard, because these are the happy breeding grounds of mosquitoes. Remove empty birdbaths, drains, wheelbarrows and flowerpots, along with old tires and unused containers that might contain water. Draw off puddles while possible. Make your gutters dirt free and drain flat roofs frequently.
A Caesarian section (C-section) can be done if the mother receives active herpes lesions in order to protect the newborn.
3 doses of the vaccine can prevent Japanese encephalitis. Take measures at the time of traveling to parts where this infection is common.
The elderly and pregnant women should be given extra care. The elderly have greater chance of having symptoms with infection. On the other hand the Japanese encephalitis virus can infect the fetus and cause its death. Therefore, these 2 groups should be alert while going abroad.
Seek outdoor signs of viral infection. If you detect sick or dying birds, report your local health department.