Allergy to pigeon tick ("Argas reflexus") in Upper Silesia, Poland

The pigeon tick Argas reflexus is avian ectoparasite that typically feeds on pigeons. When devoid of a natural host, the ticks can also attack humans. In Upper Silesia, southern Poland, people living in the vicinity of the birds’ nesting sites are frequently bitten by A. reflexus. The bites can provoke serious allergic reactions, including fatal anaphylactic shock. In the present study, residents of 9 apartments invaded by pigeon ticks were invited to undergo medical examination, skin prick tests (SPT) and determination of specific IgE to A. reflexus. The test allergens were prepared of ticks collected on-site. Out of 18 residents living in the infested apartments, 15 accepted the invitation. In this group, 8 persons complained of tick-related health problems, positive SPT to A. reflexus were found in all of them, and specific IgE was detectable in 3 persons (range: 0.38–0.84 kUA/l; CAP class 1–2). Final clinical diagnoses were established of generalised urticaria with asthma in 1 person, generalised urticaria in another 1, and local allergic reactions to tick bites in the remaining 6. Among 7 symptom-free residents, all test results were negative. Besides the study group, the paper also describes the case of a person who developed hypersensitivity to A. reflexus as a child, after a few visits to an abandoned dovecote. 30 years later, positive SPT (++) and specific IgE (0.78 kUA/l; CAP class 2) were still present despite no further re-exposures. The article also discusses available pest control measures against A. reflexus.