Researchers look for infectious ticks in Helsinki’s Lauttasaari district

Ticks are examined for borreliosis but also for dreaded tick-borne encephalitis (TBE)

print this

By Jussi Sippola
     
      A research party will set out to look for infectious castor bean ticks (Ixodes ricinus) in Helsinki’s Lauttasaari district in June.
      In Helsinki the castor bean tick was last studied in depth about ten years ago on the island of Seurasaari. At that time it was observed that more than half of the ticks on the island were infected with bacteria belonging to the genus Borrelia. These bacteria cause borreliosis or Lyme disease.
      Now the researchers are also examining ticks for Tick-borne encephalitis, the prevalence of which is clearly on the up. Tick-borne encephalitis (TBE), or “Kumlinge Disease” (after the island in the Åland Archipelago of that name), is a significantly more serious illness than borreliosis, and can even be fatal in one or two per cent of cases.
      Professor Antti Vaheri from the University of Helsinki assumes that the ticks in Lauttasaari will be widely infected at least with borreliosis.
     
The more serious tick-borne encephalitis has so far been encountered in Helsinki in only one place, the Isosaari island that belongs to the Defence Forces. Last year a national serviceman contracted the disease there.
      Through hosts such as rodents and birds, ticks carrying the dreaded TBE can spread elsewhere as well.
      Last year 44 people in Finland were diagnosed with TBE. Nine of the cases were in the area of the Hospital District of Helsinki and Uusimaa (HUS).
      “More than likely these people contracted the disease elsewhere than in the capital area”, Professor Vaheri says.
      TBE is most common in the Åland Islands.
     
From a tick bite, TBE is contracted immediately, unlike borreliosis, which may take up to ten hours to be transmitted after the bite.
      Between 10 and 50 per cent of ticks carry the borrelia bacterium, which causes borreliosis. The TBE virus that causes the Kumlinge Disease is only found in about 1% of ticks.
      Borreliosis is a bacterial infection, which, when caught early, can be treated with antibiotics.
      Untreated it may lead to a wide range of skin, nervous system, joint, and heart conditions. Last year, more than 1,400 cases of borreliosis were documented in Finland.
      TBE begins with symptoms similar to those of flu. Some of the people who have contracted the disease will later develop neurological symptoms. The disease can be prevented by vaccination.
     
As ticks thrive in moist undergrowth, the best way to protect oneself against them is to cover the skin with clothes.
      For those moving in an area that is known for ticks, it pays to use long trousers and long-sleeved shirts. The ankles should be protected by boots or socks pulled over the trouser legs.
      Ticks are less likely to get caught in smooth fabrics.
      In tick-infested areas, skin and clothes should be checked twice a day. Pets should also be inspected.
     
Those moving about in Lauttasaari can email their tick findings to the research group at punkit@saaristolaakarit.fi.
      The group consists of researchers from the University of Helsinki and doctors and nurses from the private medical practice Saaristolääkärit Oy.
     
     
Helsingin Sanomat / First published in print 29.4.2011


Previously in HS International Edition:
  FACTFILE: Ticks spread two diseases (19.6.2007)
  Virus researchers collect over 1,000 ticks from Turku Archipelago (19.6.2007)

See also:
  Damp summer weather favours ticks (23.6.2004)

Links:
  Ixodes ricinus (Wikipedia)
  Tick-borne encephalitis (Wikipedia)
  Lyme disease (Wikipedia)

JUSSI SIPPOLA / Helsingin Sanomat
jussi.sippola@hs.fi