Poisonous caterpillar health problems expected next year; Major spike last June

Oak processionary caterpillars
Oak processionary caterpillarsPhoto: Luc hoogenstein/Wikimedia Commons

Doctors in the Netherlands reported a major spike in patients this past June for complaints related to the poisonous oak processionary caterpillars. Primary care physicians in the last week of June saw a 4.5 times more patients than in other weeks, according to care research organization Nivel.

Similar problems are expected next year, the institute said, and will continue until the caterpillar invasion is under control. The health issues were caused by the hairs of the caterpillar, and babies and toddlers were among the worst affected.

“Exposure to the stinging hairs is associated with all sorts of skin, eye and respiratory complaints. In addition to annoying itching and bumps, the symptoms are often accompanied by redness and pain,” the report stated.

Sharp increases in complaints were reported in Drenthe, Gelderland, Noord-Brabant, Overijssel, and Utrecht. About 150 people out of every 100 thousand residents visited their care providers for reports of itching in the 26th week of 2019.

The national average from June 24-30 this year was about 85 people per 100 thousand. That number was closer to 20 most other weeks in 2019, and also during week 26 of previous years.

Most common symptoms reported were skin rashes, blotchy skin, and itching. The organization managed to link the symptoms to the caterpillar, in part because there was not a substantial spike in hay fever complaints that week.

Nivel speculates that even more people had problems this year because not everyone visited the doctor. Caterpillar-related complaints were most prominent from June 17 through July 14.