Japanese encephalitis
It’s no fun falling ill or catching a virus when you are off on vacation. Here we explain Japanese encephalitis, where it can be contracted and how you can reduce your risk when travelling.
What is Japanese encephalitis & how do you catch it?
Spread through mosquito bites, Japanese encephalitis is a rare but serious viral brain infection. The virus starts with a mosquito biting an infected pig or bird, then going on to bite a human, transmitting the disease. The infection can’t be passed from person to person.
Japanese encephalitis is found throughout Asia and beyond. Most cases occur in:
- China
- Myanmar (Burma)
- Thailand
- Vietnam
- Cambodia
- Laos
- Nepal
- India
- Philippines
- Sri Lanka
- Malaysia
- Indonesia
Signs and symptoms of Japanese encephalitis
Unlikely to always present symptoms but when contracted, Japanese encephalitis symptoms are usually mild and flu-like.
One in every 250 people develop more severe symptoms. This usually takes place five to 15 days after infection when it spreads to the brain. Severe Japanese encephalitis symptoms can include:
- High temperature (fever)
- Seizures
- Stiff neck
- Confusion/ Inability to speak
- Uncontrollable shaking of body parts
- Muscle weakness or paralysis
As these can be signs of many different diseases, you should seek immediate medical attention if you become unwell with flu-like symptoms and any of the symptoms listed whilst away or on your return.
Vaccination
The vaccination, given as an injection, is administered in two doses for protection. The second dose can either be given 28 days after the first, or, when time is short, seven days after the first (an ‘accelerated’ schedule). The two doses should be completed at least seven days before your departure.
If you’re at higher risk of the disease, you should consider being vaccinated. It’s particularly important if:
- You’re travelling to a high-risk country during rainy season
- You’re visiting rural areas such as rice fields, marshlands or animal farms
- You’re likely to be doing activities that could increase your risk, such as cycling or camping
How long do cholera vaccinations last?
10 years, however, if you’re at prolonged risk of infection, you should have a booster injection 12 to 24 months after the initial vaccination.
Travel & Immunisation Clinic
Signs and symptoms
Those who have picked up the cholera bacteria don’t always have symptoms, but these are some of the typical symptoms you should expect:
• Severe, watery diarrhoea
• Nausea
• Vomiting
• Stomach cramps
Cholera symptoms can occur after just after a few hours, but generally develop within a few days of picking up the infection. If untreated, dehydration from severe diarrhoea and vomiting can quickly take effect, causing the body to go into shock because of a big drop in blood pressure.
Prevention
If you are travelling to a country known to be affected by cholera, here are a few ways you can help protect yourself:
• Only drink boiled or sealed bottled water
• Avoid ice in your drinks and ice creams
• Wash (in safe water) or peel uncooked fruit and vegetables
• Avoid shellfish, seafood and salads
Practice good personal hygiene measures – always wash your hands in safe water before eating and visiting the bathroom
Vaccination
The risk to most travellers is very low and vaccination is usually only recommended in the following circumstances:
• Volunteers/aid workers/medical personnel in disaster relief situations where cholera outbreaks are likely
• Those travelling to work in slums/refugee camps or areas affected by natural disasters
• Those travelling to countries experienacing cholera outbreaks and where care with food and water is difficult or not possible
The drinkable cholera vaccine is given in two or three (depending on age) separate doses, taken from one to up to six weeks apart and completed at least a week before travelling.