Serum antibodies and DNA indicate a high prevalence of equine papillomavirus 2 (EcPV2) among horses in Switzerland.
BACKGROUND
The DNA of equine papillomavirus type 2 (EcPV2) is consistently found in equine papillomas and squamous cell carcinomas, indicating a causal association of EcPV2 in the pathogenesis of these tumours; however, little is known about the prevalence of this virus.


OBJECTIVE
The aim of this study was to determine the geno- and seroprevalence of EcPV2 in clinically healthy horses in Switzerland.


METHODS
Fifty horses presented to the equine department of the university clinic, displaying no skin or mucous membrane lesions or severe signs of other diseases, were sampled.


METHODS
Cytobrush samples from the penis or vulva and serum samples were collected. To determine the genoprevalence of EcPV2, DNA was extracted from cytobrush samples and tested for viral DNA with a PCR assay amplifying a 338 bp fragment of the E7/E1 region of the viral genome. Seroprevalence was tested using an enzyme-linked immunosorbent assay aimed to detect antibodies against the major capsid protein (L1) of EcPV2.


RESULTS
In five of 50 horses (10%), EcPV2-specific DNA was amplified but no antibodies could be detected, whereas in 14 of 50 horses (28%), antibodies against EcPV2 but no DNA were demonstrated. Both antibodies and viral DNA were detected in four of 50 horses (8%). Neither antibodies nor viral DNA were found in 27 of 50 horses (54%).


CONCLUSIONS
The seroprevalence suggests that EcPV2 is prevalent in the Swiss equine population, while the genoprevalence indicates that currently ongoing infections are less common. The discrepancy between geno- and seroprevalence probably indicates different stages of infection in the tested cohort.
Dermatology Department, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Nina M
NM
Fischer
Dermatology Department, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Claude
C
Favrot
Equine Department, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Katharina
K
Birkmann
Equine Department, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Michele
M
Jackson
Equine Department, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Colin C
CC
Schwarzwald
Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 242, 69120 Heidelberg, Germany.
Martin
M
Müller
Institute of Virology, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Kurt
K
Tobler
Dermatology Department, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.|Institute of Virology, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.
Marco
M
Geisseler
Dermatology Department, Clinic for Small Animal Internal Medicine, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.|Institute of Virology, Vetsuisse Faculty, Winterthurerstrasse 260, 8057 Zurich, Switzerland.|Microbiology and Immunobiology Department, Harvard Medical School, 77 Ave Louis Pasteur, Boston, MA 02115, USA.
Christian E
CE
Lange
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D004279:DNA, Viral / Q000097:blood*; D006734:Horse Diseases / Q000453:epidemiology / Q000821:virology*; D006736:Horses; D027383:Papillomaviridae / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D030361:Papillomavirus Infections / Q000453:epidemiology / Q000662:veterinary*; D016036:Seroepidemiologic Studies; D013557:Switzerland / Q000453:epidemiology
D000914:Antibodies, Viral; D004279:DNA, Viral