[Ehrlichiosis is common among animals but can also occur in humans]

Granulocytic ehrlichiosis is attracting increasing attention as a disease of both humans and animals. Pasture fever in cattle is a form long known in Sweden, and a similar disease was observed in Swedish dogs and horses in the late 1980s. The first cases of human granulocytic ehrlichiosis (HGE) reported from the USA in 1994 proved to have been caused by a species of Erhlichia identical or very similar to the species found in Swedish dogs and horses. Presence of the HGE agent has now been demonstrated in Ixodes ricinus ticks in Sweden. Serological studies among residents in areas of Sweden with a high incidence of ticks have shown the presence of antibodies against the HGE agent in over 10 per cent of cases. To date, there have been about 10 documented cases of HGE in Sweden, a figure to be compared with those for dogs and horses among which ehrlichiosis is relatively common.