Infektion mit dem felinen Leukämievirus – der Weg zur Diagnose

Zusammenfassung

Die Infektion mit dem felinen Leukämievirus (FeLV) kommt bei Katzen weltweit vor. Der Verlauf einer Infektion kann unterschiedlich sein und sich über die Zeit verändern. Die komplexe Pathogenese, die Verfügbarkeit vieler verschiedener Testverfahren und die Interpretation der Testergebnisse stellen Tierärzte oftmals vor eine Herausforderung. Katzen mit einer progressiven Infektion (persistierend p27-Antigen-positiv) scheiden FeLV vorwiegend über den Speichel aus und gelten daher als Ansteckungsquelle für andere nicht infizierte Katzen. Schwieriger zu erkennen sind Katzen mit einer regressiven Infektion, da sie mit herkömmlichen Schnelltests (p27-Antigentest) in der Regel nicht erfasst werden und unerkannt bleiben. Dennoch sind diese Katzen FeLV-Träger (Provirus-positiv) und bei Schwächung des Immunsystems kann es zu einer Reaktivierung der Infektion und FeLV-assoziierten klinischen Symptomen kommen. Abortiv infizierte Katzen sind zu keinem Zeitpunkt virämisch, scheiden kein Virus aus und entwickeln keine klinischen Symptome. Eine abortive Infektion kann nur durch den Nachweis von Antikörpern im Blut diagnostiziert werden. Ein neuer Schnelltest zum Nachweis von Antikörpern gegen FeLV-p15E-Antigen wurde kürzlich auf dem europäischen Markt eingeführt und wird gerade evaluiert.

Abstract

Feline leukemia virus (FeLV) infection affects cats worldwide. The course of FeLV infection can change and vary over time. The complex pathogenesis, the availability of many different testing methods, and the interpretation of test results are often challenging for veterinarians. Cats with progressive infection (persistently p27 antigen-positive) shed FeLV mainly through saliva and are therefore considered a source of infection for uninfected cats. Diagnosing regressive infection is often challenging, since it usually cannot be detected by commonly used point of care-tests (p27 antigen test) and thus, it often remains undetected. Nevertheless, cats with regressive infection are FeLV carriers (provirus-positive) and when the immune system is suppressed, reactivation of the infection and FeLV-associated clinical signs can occur. Abortively infected cats are never viraemic, do not shed virus, and do not develop clinical signs. Abortive infection can solely be diagnosed via antibodies detection in blood. A new point-of-care test for the identification of antibodies against FeLV p15E antigen has recently been introduced on the European market and is currently being evaluated.

Schlüsselwörter

FeLV - p27-Antigen - virale RNA - provirale DNA - anti-FeLV-Antikörper

Key words

FeLV - p27 antigen - viral RNA - proviral DNA - anti-FeLV antibodies

Publication History

Received: 22 November 2021

Accepted: 10 March 2022

Article published online:
05 July 2022

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