Characterization of Emerging Human Dirofilaria repens Infections, Estonia, 2023

Area of Science:

• Veterinary parasitology
• Medical entomology
• Public health

Background:

• Mosquito-borne diseases pose a significant global public health risk.
• Human dirofilariasis, caused by Dirofilaria repens and transmitted by mosquitoes, is expanding into new European regions.
• Limited data exists on the presence and spread of Dirofilaria repens in Northern Europe.

Purpose of the Study:

• To report the first molecularly confirmed cases of autochthonous human Dirofilaria repens infection in Estonia.
• To document the emergence of this parasitic nematode in a previously unrecorded area.
• To contribute to understanding the geographic expansion of mosquito-borne diseases.

Main Methods:

• Molecular confirmation of Dirofilaria repens in human clinical samples.
• Case identification and clinical data collection.
• Geographic and entomological context assessment.

Main Results:

• Molecularly confirmed autochthonous human Dirofilaria repens infections were identified in Estonia.
• This represents the first documented occurrence of human dirofilariasis in the country.
• The findings indicate a northward expansion of the parasite's range in Europe.

Conclusions:

• Estonia is a newly identified endemic area for human dirofilariasis.
• The findings underscore the need for increased surveillance of mosquito-borne diseases in Europe.
• Public health awareness and vector control strategies may be necessary in affected regions.