Vaccination of Zoo Birds against West Nile Virus—A Field Study

Neonatal Care of Anseriformes

Neonatal Anseriformes require specialized care for successful development including access to clean swimming water and food presentation that stimulates natural feeding behavior. Knowledge of natural history is essential for successful rearing. Lightweight and waterproof materials can be used for corrective splinting of many developmental disorders that allow birds to ambulate normally and swim. Captivity-associated lesions can be minimized through proper husbandry and hygiene. Anseriformes are susceptible to a variety of bacterial, viral, fungal, and parasitic diseases, some of which are reportable to state health agencies.

A Prior Usutu Virus Infection Can Protect Geese from Severe West Nile Disease

Usutu virus (USUV) and West Nile virus (WNV) are closely related pathogens circulating between mosquitoes and birds, but also infecting mammals as dead-end hosts. Both viruses share the same susceptible hosts, vectors, and even distribution areas in Central Europe. The aim of the study was, therefore, to understand their amplification potential and interference upon a successive infection. Two-week old geese were initially infected with an USUV isolate from Germany and with a German WNV isolate17 days later. The geese were susceptible to the USUV and the WNV infections, as evidenced by specific flavivirus antibodies in all of the birds. Furthermore, in half of the USUV-inoculated geese, USUV genomes were detected in the blood and swab samples 2-4 days post-infection. Additionally, most of the examined organs contained USUV genomes and showed signs of encephalitis and ganglioneuritis. Interestingly, upon a sequential infection with WNV, the genome copy numbers in all of the examined samples were significantly lower and less frequent than after a WNV mono-infection. Similarly, the histopathological lesions were less severe. Therefore, it can be concluded that a previous USUV infection can protect birds from clinical disease in a subsequent WNV infection.