Animals – insects
Reading time: 6 minutes
A small black and red body about the size of a sewing needle’s head dances with all eight of its legs atop a hot, sweaty patch of skin. Then he stopped.
Next, he thrusts his toothy suckers, with chins on, into the skin to slurp up the gushing blood.
The forest tick is the most dangerous animal in the Nordic countries. It is estimated that he bites around 200,000 Nordic people every year. Scientists also believe that the number of animals there increases every year.
The forest mite has been very rare in this country, but around the turn of the century it has been found more and more often, and today it is probably considered endemic in this country.
The reason is believed to be increased temperature. Forest ticks thrive in moist, warm summers, but another important reason is that the tick’s host, i.e. the animals on which it lives, especially deer and mice, move further and further north.
According to René Bødker, a researcher at the Department of Veterinary Medicine and Animal Science at the University of Copenhagen, the number of wood ticks has increased enormously in Denmark since the 1980s. However, René does not believe that the weather is solely to blame.
In the years up to 1980, around 80,000 deer lived in the Nordic countries. Today there are about half a million animals. Similarly, the number of forest ticks has increased enormously.
Rarely is there a single bar
The wood tick is not dangerous in itself. However, it can infect people it touches with two diseases that can have very serious consequences on our health.
First of all, it is a so-called Lyme disease, which is caused by a bacterium called borrelia burgdorferi . This bacterium can cause rheumatic pain, myocarditis, brain, meninges and neuritis. In the worst case, it can result in incurable paralysis.
Secondly, it is the so-called TBE virus (tick borne encephalitis), also known as “Central European encephalitis”, which can cause paralysis, brain damage, and even death in the worst case scenario.
The TBE virus is spreading at an alarming rate. In many European countries, the incidence of the TBE virus has increased significantly. The situation peaked in 2018.
Number of people infected with TBE
No one is known to have been infected with TBE in this country.
In the years 2012-2016, 253 people were infected in Finland. This corresponds to 63 persons per year.
In Norway, a total of 47 infections were detected during the same period, which corresponds to 12 people per year.
About three people become infected each year in Denmark, and more often than not the infection is detected in Borgundarhól.
However, most of the infected live in Sweden, but there were no less than 1,180 infected in the years 2012-2016.
Source: Euro Serveillance , Statens Serum Institut
Research has revealed that the vectors are mainly adult wood ticks and more often than not they are females.
There are about 900 species of blood ants in the world. It should be noted that only one species lives in Denmark, and it is ixodes ricinus , which in Icelandic is called forest tick.
The risk of contracting Lyme disease or TBE virus is greatest during the summer months, from June to September.
Ticks are infected by blood from mice
The tick’s life cycle lasts from two to five years and includes four stages: egg, larva, pupa and adult. The gilts are infected with borrelia and/or TBE from infected mice.
1 – Spring: The tick emerges
The eggs laid by an adult tick in the forest floor hatch.
2 – Summer: The first victim
The small newly hatched ticks, i.e. the larvae, attach themselves to the first victims. Very often it is mice. Mice can be infected with borrelia bacteria or a virus that is transferred to the larva.
3 – Next spring: From larva to pupa
The next spring, the larvae will change mode and they will turn into nymphs, which, unlike the larvae, can bite and suck blood from humans and larger animals.
4 – Autumn: The tick becomes an adult
The mite has once again metamorphosed and the tick is now fully grown. The adult animal can also suck blood from humans. The next spring, the tick lays eggs and the life cycle closes.
5 – Spring and Summer: The off season
The risk of being bitten by wood ticks and adult ticks is greatest in spring and summer.
The number of people infected with Lyme disease
Borrelia lives a good life. It is estimated that around 85,000 people become infected each year. About 65,000 of these infections occur in Europe, the vast majority in Scandinavia.
Fortunately, no case has been confirmed in this country.
Most of them are infected in Sweden, as is the case with TBE infections. 40-50,000 people get infected there every year. About ten percent of those who get Lyme disease in Sweden get sick with dangerous neuritis.
In Finland, about 1,900 people get Lyme disease every year. There, researchers are also aware of a large increase in Lyme-infected people.
Every year, around 150 people in Denmark fall ill with this life-threatening neurological disease that causes paralysis. However, the infections in Norway are approximately half as many as in Denmark.
Sources: La Sapienza University in Italy, University of Georgia in the USA and Turku University in Finland.
This should be done…
If you plan to walk through the woods during the summer months, be sure to use paths, wear rubber boots, and check for tick bites on your skin (mainly in damp places) when you get home.
There are many house tips. Unfortunately, many of them are unfounded. If a tick has bitten, simply remove it with a pair of chip tweezers.
It doesn’t matter if a small part remains in the skin. If the tick has been in the skin for less than 24 hours. there is usually no risk that he has carried the borrelia bacteria with him.
However, if you notice circular redness around the bite wound one to two weeks later, there is a risk that you have nevertheless been infected. In such cases, a doctor should be sought.
The doctor prescribes a dose of antibiotics that often kills the borrelia bacteria. Lyme disease therefore only causes paralysis and death if the illness is not discovered until two weeks later.
However, the TBE virus is instantly contagious.
If you are bitten, it usually takes 10-14 days for fever, fatigue and muscle aches to appear. Three-quarters of those exposed to TBE do not develop symptoms other than these, but a quarter develop encephalitis.
There is no cure for TBE. However, it should be noted that those who travel frequently to areas where there is a high risk of TBE can get vaccinated.
Published August 7, 2021
Michael Leander
