Japanese encephalitis is a type of viral brain infection and inflammation that spreads through a mosquito bite, especially in rural areas of most of Asia. Mosquito bites infect animals and birds, which in turn transmit the disease to people through bites; however, the infection cannot subsequently spread directly from one person to another. Most affected individuals have only mild flu-like symptoms, but a small minority of cases require emergency medical attention. It can be difficult to recognize the signs of this condition, but it is important to keep an eye on infected people (usually children) in case the situation suddenly worsens.
Steps
Part 1 of 2: Recognizing the Symptoms
Step 1. Pay attention to flu-like symptoms
Most people with Japanese encephalitis are completely asymptomatic or have only mild, short-lived discomforts that resemble those of the flu: light or moderate fever, fatigue, headache, and sometimes vomiting. For this reason, it is very difficult to recognize most cases of this pathology: no symptoms are noticed or they mainly resemble many other mild infections.
- It is estimated that less than 1% of encephalitis virus patients develop overt symptoms.
- In those who manifest the disease, the incubation period (the time from the infectious infection to the onset of symptoms) generally lasts from 5 to 15 days.
Step 2. Make a note of the high fever
Although symptoms are usually very minimal or none at all, about 1 in 250 cases can progress to severe illness, often starting with a high fever. High body temperature is a defense mechanism of the body to slow or stop the production of viruses (or bacteria) that are invading the body, but when it exceeds 39 ° C in adults or 38 ° C in children, there is the risk of brain damage. In turn, the high fever and worsening brain inflammation caused by encephalitis can trigger other serious and potentially life-threatening symptoms.
- When significant symptoms of this infection occur - usually in children with weak immune systems - the chances of death are about 30%.
- In moderate cases, the body temperature can rise by a couple of degrees, but in very severe cases the fever can peak by as much as five degrees or more.
Step 3. Check for nuchal stiffness
As in other types of infections that affect the brain and / or spinal cord (such as meningitis), this symptom can also occur in the case of Japanese encephalitis. You may experience a sudden sensation of stiffness in your neck and an inability to move it in all directions, but most of all you may experience a sharp, stinging or electric shock-like pain when you bend it (when you try to touch your chest with your chin).
- When the spinal cord is inflamed, the muscles near the spine contract a lot in an attempt to protect it; as a result, they become stiff to the touch and may experience spasms. Nuchal stiffness is one of the meningeal signs.
- There is no medication, massage, or chiropractic treatment that relieves this neck stiffness due to Japanese encephalitis, meningitis, or other central nervous system infections.
Step 4. Pay attention to mental or behavioral changes
Another effect induced by brain inflammation and severe fever is mental changes, such as a sense of disorientation, confusion, difficulty concentrating and even an inability to speak. Behavioral changes are often interrelated and consist of irritability and / or inability to control temperament, as well as a willingness to be alone and avoid social contact.
- The most severe symptoms of the infection, once started, take only a few days to become dangerous or significant.
- The mental and behavioral changes associated with severe cases of Japanese encephalitis can resemble a stroke or Alzheimer's; the patient goes from being a healthy and completely autonomous person to one with severe physical and mental deterioration.
- Be aware that to increase the chances of survival it is vital to recognize the signs, symptoms and then intervene in a timely manner.
Step 5. Check for neurological damage
As the infection begins to worsen with increased swelling and a high fever, neurons in the brain begin to damage and die; when this occurs, neurological signals begin to be noticed, such as uncontrollable shaking of certain parts of the body, muscle weakness or paralysis, difficulty walking or grasping objects, and impaired coordination (awkward movements).
- Muscle weakness and paralysis typically begin to develop in the limbs (arms and legs) and progressively spread to the rest of the body, although the face is sometimes affected first.
- Among those who survive the severe outbreaks of this pathology (about 70% of cases), on average 1/4 suffer neurological damage and / or behavioral problems, as well as permanent disabilities.
Step 6. Be prepared for seizures
The progression of a severe attack of Japanese encephalitis inevitably ends in seizures, which are caused by brain swelling, high fever, and electrical discharges / changes in the neurons of the brain. Such seizures lead to collapse, agitation, muscle spasms, jaw blockage, and sometimes vomiting or foam in the mouth.
- Encephalitis-induced seizures can resemble seizures, but can be more serious and potentially life-threatening due to brain damage.
- Children with this infection are more likely than adults to suffer from seizures because their brains are smaller, more susceptible to pressure and increased temperature.
- Once the seizures have started, it is not uncommon to lose consciousness and go into a coma.
Part 2 of 2: Preventing Japanese Encephalitis
Step 1. Get the vaccine
According to the World Health Organization (WHO), the safest and most effective way to prevent this disease is to get vaccinated. The four main types of vaccines currently used to prevent this infection are an inactivated vaccine derived from a mouse brain, an inactivated vaccine derived from VERO cells, a live attenuated one and a live one with recombinants. You should get vaccinated at least six to eight weeks before traveling to Asia so that your body has enough time to develop the antibodies it needs to protect itself.
- The one most often used against this infection is the live attenuated vaccine SA14-14-2, which was first introduced in China.
- The greatest risk of contracting this disease in Asia occurs in rural areas of parts of Japan, China and Southeast Asia; you should therefore get vaccinated before going to these places to reduce the risk of contagion.
- Vaccination involves several doses to be administered over a few weeks or months.
- Keep in mind that sometimes the vaccine itself (of any kind) can cause or aggravate encephalitis by an allergic reaction to the ingredients in it.
Step 2. Avoid mosquito bites
Another way to protect yourself from infections is to control the presence of these insects and avoid getting stung, as they are the main vector of the disease. To do this, avoid or eliminate any sources of standing water where mosquitoes can breed and always use a DEET-based repellent (you can find many brands on the market). Also, make sure your bed is protected by a mosquito net (or other mesh cover) and avoid going outdoors between dusk and dawn, when mosquitoes are most active and fly.
- Most repellent products are effective for up to six hours, and some are water resistant.
- Do not apply products containing DEET on infants who are less than two months old.
- Among the natural repellents you can choose as an alternative to chemicals consider lemon or eucalyptus oil.
- By limiting the risk of mosquito bites when traveling abroad, you also reduce the risk of contracting other serious diseases, such as malaria and West Nile virus.
Step 3. Put on protective clothing
In addition to applying repellent and using the mosquito net, you should also wear appropriate clothing to protect yourself when traveling in Asia, especially in rural countryside areas. Then put on long-sleeved shirts and thin cotton gloves (very popular in several Asian countries) to completely cover your arms and hands. As for the legs, wear long pants with socks and shoes when outdoors, especially when walking in grassy and swampy spaces.
- Many Asian regions are very hot and humid for most of the year, so wear breathable long-sleeved trousers and shirts so you don't overheat.
- However, keep in mind that mosquitoes can also bite through thin clothing, so you should spray a repellent product on your clothing as well for added safety. however, do not apply a permethrin-based repellent directly to the skin.
Step 4. Don't engage in risky outdoor activities
If you're in Asia, avoid those that can significantly increase your risk of getting bitten and infected by mosquitoes, such as camping, hiking, and exploring by motorbike or bicycle. Not only are these activities that are usually done in rural areas, but they make you vulnerable due to exposure. If you want to travel for pleasure, choose to travel in closed vehicles (tour buses) when you are in rural areas and wear protective clothing, as already described above.
- If you absolutely must sleep outdoors when in rural Asia, it is extremely important to cover your tent or house with a mosquito net impregnated with a powerful insecticide.
- While in the countryside, sleep only in hotel rooms with mosquito nets or guards on windows and doors.
Step 5. Don't travel to Asia
Another form of prevention, albeit drastic, consists in not going at all to Asian countries known for the endemic presence of Japanese encephalitis, which in reality is now widespread in the main states of Asia. This represents easy advice to follow for curious travelers who have no family ties or other correlations with Asian countries, but it is not easy to put into practice for all those people who have to go to these places for work or family reasons. In fact, the risk of contracting the virus is very low - it is estimated that fewer than one in a million travelers in Asia get sick every year.
- A more practical tip is to avoid rural areas if you have to travel to these countries, especially the farming areas where there are many pigs and cows.
- The people most at risk of contracting the virus are those who live and work in rural areas where the disease is widespread, especially children and young people under 15.
- If you have the choice, avoid traveling to Asian countries during the rainy seasons (they vary from one area to another), when mosquitoes are more resistant and pose a greater threat.
Advice
- Japanese encephalitis is the leading cause of viral encephalitis in Asia.
- In some cases, patients with this virus may take anticonvulsant drugs to prevent seizures and corticosteroids to reduce brain edema.
- It can happen to contract this infection especially in rural and non-urban areas.
- The incubation period typically lasts from 5 to 15 days.
- About 75% of cases of infection occur in children under 15.
- The World Health Organization estimates that around 68,000 cases of this infection occur worldwide each year.
- There are no antiviral drugs to treat it; the most severe cases are managed with supportive therapies, which often include hospitalization, respiratory support and administration of intravenous fluids.
