GENEVA — Scientists in Switzerland are hunting for a species of mosquito capable of spreading the tropical disease dengue that may have crossed the Alps.

The Swiss Tropical and Public Health Institute has laid 250 traps along roads and rivers to see whether the tiger mosquito has successfully penetrated the natural border between northern and southern Europe.

The black-and-white striped species originally from Southeast Asia has established itself in Italy, and individual specimens have been found in other European countries in recent years.

The Swiss institute's mosquito specialist, Pie Mueller, told public radio station SRF 1 on Wednesday that there was no cause for alarm but that the risk to human health should be taken seriously.

The tiger mosquito is also blamed for spreading West Nile virus, yellow fever and other diseases.