Original Scientific Article
Distribution of Porcine Circovirus 2 in wild boar in Estonia
Tõnu Järveots * ,
Tiiu Saar ,
Toivo Suuroja ,
Piret Hussar

Mac Vet Rev 2026; 49 (2): i - xi

10.2478/macvetrev-2026-0019

Received: 07 November 2025

Received in revised form: 17 March 2026

Accepted: 28 April 2026

Available Online First: 07 July 2026

Published on: 15 October 2026

Correspondence: Tõnu Järveots, onu.jarveots@emu.ee
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Abstract

Porcine Circovirus 2 (PCV2), member of the Circoviridae family, is globally prevalent virus in domestic pigs and wild boars, causing a group of diseases known as porcine circovirus-associated disease (PCVAD). Given its significant economic impact and potential for interspecies transmission, surveillance in wild boar populations is essential. As to date, no data exist on PCV2 prevalence in Estonian wild boars. The study aimed to assess the seroprevalence of PCV2 in Estonian wild boar populations by age and sex, and evaluate tissue-level histopathological changes and antigen localization to support serological findings. Blood and lymphnode material from wild boars were collected randomly from all Estonian counties (n=433). They were divided into three age groups and subdivided by sex. Detection of PCV2-specific antibodies was performed using ELISA (INGEZIM Circo IgG 11.PCV.K.1®). Histopathological and immunohistochemical (IHC) examinations were conducted on mesenteric lymph node sections using hematoxylin-eosin and PCV2-specific monoclonal antibodies. Statistical analysis was conducted with Python (version 3.13.0, 2024). PCV2 antibodies were detected in 92% of samples, indicating widespread viral exposure. Highest seroprevalence was observed in wild boars aged ≤1 year, followed by 1-2 year and >2 year groups. No statistically significant differences in positivity were found between age groups (p=0.199) or sexes (p=0.453). Histopathology revealed lymphocyte depletion and histiocyte proliferation in lymphoid tissues and IHC examination confirmed PCV2 antigen presence in cytoplasm of lymphocytes and histiocytes. The high seroprevalence of PCV2 detected in Estonian wild boars aligned with findings from other European countries.

Keywords: PCV2, wild boars, epidemiology, ELISA

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Copyright  

©2026 Järveots Т. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Conflict of Interest Statement

The authors declared that they have no financial or non-financial conflict of interest regarding authorship and publication of this article.

Citation Information

Macedonian Veterinary Review. Volume 49, Issue 2, Pages i-xi, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI:  https://doi.org/10.2478/macvetrev-2026-0019

The all content of the Macedonian Veterinary Review, except where otherwise noted, is licensed under a Creative Commons Attribution License.