Spring has arrived and the first Asian tiger mosquitoes, Aedes albopictus, have made an appearance in Europe. They have done so on the Mediterranean coast of the Iberian peninsula and in the north of the Italian peninsula, but they were not the most active species during the first quarter of 2021.

In the first, cold months of the year, the most widely reported species sought is the common house mosquito, Culex pipiens. Some authors define two different biotypes of this species, Culex pipiens pipiens and Culex pipiens molesus. While the first form goes into diapause in winter without showing activity, the molestus form remains active and continues to bite throughout the winter. These active forms are what would explain the reports received of this species throughout January, February and March. Its activity has been detected in the Netherlands, Austria, Albania, Italy and Spain.

Even so, in these first months most of the reports correspond to species of insects not included in the Mosquito Alert app (21%) or reports of which it has not been possible to identify the species from the photograph (56.8%) . The common mosquito has accounted for 16% of the total reports received, while the few tiger mosquitoes that have arrived during the quarter represent no more than 1.7%.


Culex pipiens has been the most detected species during the winter months


Mosquito reports have been received from 153 European municipalities. The municipalities that have had a greater participation in these months have been mainly Spain, Italy, Hungary and the Netherlands, although mosquito warnings have arrived from more than ten different European countries, for a total of 497 reports.


In the same period, 585 reports of mosquito bites have been sent, reporting a total of 2811 bites. Most of the bites took place during the night (66.6%) or in the afternoon (15%), being much less frequent during the morning (9%) and at noon (9%). Almost three out of four bites took place inside a building (71%), one in five outside (20%) and the rest inside a vehicle (9%).

Most mosquito bites have taken place inside a building (71%), 20% outside and 9% inside a vehicle.

What part of the body receives the most bites? In the data for this quarter there are no differences, all parts are equally stung, with slightly higher values in the extremities: arms and legs, and somewhat lower in chest and head.

In summary, during the first quarter of the year we received practically the same number of reports of bites as of mosquitoes. Among mosquitoes, the target species has so far represented a small percentage that we hope will change now that mosquito season begins.