What is tick-borne encephalitis? How did it originate?
Tick-borne encephalitis is a viral infection which can cause swelling to the brain and spinal cord and even death. It is spread by bites from ticks which are common to forests, grasslands and marshes in Europe and Asia.
What are the symptoms of tick-borne encephalitis?
Initial symptoms are similar to flu and include fever, headache, tiredness and muscle pain. These symptoms last up to 8 days, after which most people make a full recovery.
If you experience flu-like symptoms after visiting an area with a risk of transmission of tick-borne encephalitis, contact your general practitioner.
In some cases, the virus spreads to the protective membrane around the brain and spinal cord, or the brain itself.
This second stage causes more serious symptoms, which include:
- confusion, drowsiness or disorientation
- seizures (fits)
- sensitivity to bright light
- loss of ability to speak
If you have these symptoms, seek emergency hospital treatment immediately. These symptoms can take weeks to recover from, and it could take several months or years to make a full recovery. There may be long-term complications.
Seek medical advice as quickly as possible if you are bitten by a tick in a risk area and you haven’t been vaccinated against tick-borne encephalitis, or if you develop a fever or rash after receiving a tick bite.
How is tick-borne encephalitis transmitted?
You can become infected with tick-borne encephalitis when a tick carrying the virus in its saliva bites you. The tick saliva also contains an an anaesthetic, so you may not realise you’ve been bitten.
While you can get bitten any time of the year, ticks are most active from spring to early summer and most people are infected during outdoor activities such as camping, mountain biking and forest walking.
In rare cases you can contract the disease by consuming unpasteurised milk and dairy products produced from infected animals, especially goats.
What is the transmission seasonality?
Tick-borne encephalitis occurs from late spring until early autumn and is found mainly in rural/forested areas where ticks are common.
What are the infected areas in the world?
The ticks that cause tick-borne encephalitis are mainly located in forested areas of central, eastern and northern Europe. High risk areas also include eastern Russia and some countries in east Asia including South Korea and in particular forested regions of China and Japan.
What is a tick-borne encephalitis certificate?
A tick-borne encephalitis certificate proves you have been vaccinated against the disease.
Is tick-borne encephalitis curable?
There is no cure for tick-borne encephalitis but treatment can help alleviate symptoms until you recover.
If you only experience the initial flu-like symptoms, over the counter painkillers like ibuprofen or paracetamol can help ease discomfort.
If you develop second stage symptoms, you will need hospital treatment, including a drip to replace fluids and breathing assistance.
How to prevent tick-borne encephalitis?
The most effective way to avoid catching tick-borne encephalitis is to get vaccinated. This is recommended if you plan to spend a lot of time outdoors in rural areas where the disease is commonly carried by ticks. Activities such as camping, hiking, running and cycling all carry increased risk.
You should also learn ways to help avoid tick bites, even if you have been vaccinated.
To lower your likelihood of being bitten:
- keep your skin covered when walking or running outdoors, and remember to tuck trousers into socks
- apply insect repellent to bare skin and clothes – DEET is most effective
- travel on paths where available
- wear pale clothing so you can spot any ticks and brush them off.
How long before a trip do you have to get the tick-borne encephalitis vaccine?
You should get your first jab at least one month before travelling to allow enough time for the second dose before you leave, which offers 1 year of protection.
It’s best to start your vaccination from December onwards, especially if you are travelling the following year, to ensure that you have protection from the start of tick season in spring.
Who should get the tick-borne encephalitis vaccine?
You are advised to get vaccinated if you are travelling to a country where the infection is common and have plans to do outdoor activities such as camping, hiking and cycling there.
Who should not get the tick-borne encephalitis vaccine?
Most people can get the vaccine. However, if you have a severe egg allergy, or are allergic to any of the ingredients, the vaccine is not recommended.
Seek medical advice about getting vaccinated if you have:
- an autoimmune disease
- a condition affecting your brain or central nervous system
- problems with bleeding; or
- are pregnant or breastfeeding.
If you are ill, with or without a fever, you should postpone your vaccination until you’ve recovered.
What is the minimum age requirement for the tick-borne encephalitis vaccine?
The vaccine is available for children aged 1 year and up.
What is the effectiveness of the tick-borne encephalitis vaccine?
After two doses, the vaccine has a protection rate of over 90%.
What are the side effects of the tick-borne encephalitis vaccine?
Side effects are usually mild and over quickly. You may have some swelling, pain and redness at the injection site. You might also experience a fever for a day or two after the first jab.
How many jabs are needed?
To get fully protected, three injections are required. The second jab is given 1 to 3 months after the first, and provides immunity for up to 12 months. A third dose between 5 and 12 months after the second provides protection for up to 3 years.
If necessary, the timing of the doses can be shortened and 2 doses can be given 2 weeks apart.
How long does it last for?
Two doses provides protection for a year, and the third dose extends this protection to 3 years.
After that, you can get a booster jab every three years if required.
When and where was the last outbreak of tick-borne encephalitis?
According to the World Health Organization, there are around 10,000 to 12,000 cases of tick-borne encephalitis reported each year, but the true number is likely to be higher.