02516nas a2200193   4500000000100000000000100001008004100002260004400043100001300087700001800100700001300118700001400131700001500145245020700160300001200367490000800379520192100387022001402308       2007                            d  c07/2007bM. & H. Schaper GmbHaHannover1 aE Kaleta1 aK Blanco Pena1 aA Yilmaz1 aT Redmann1 aS Hofheinz00aAvian influenza A viruses in birds of the order Psittaciformes: reports on virus isolations, transmission experiments and vaccinations and initial studies on innocuity and efficacy of oseltamivir in ovo  a260-2670 v1143 aBirds of the order Psittaciformes are - besides chickens, turkeys and other birds - also susceptible to infection with avian influenza A viruses (AIV) and succumb follow-ing severe disease within one week. Published data prove that various parakeets, amazons, cockatoos, African grey parrots and budgerigars (genera Barnardius, Psittacula, Cacatua, Eolophus, Amazona, Myiopsitta, Psittacus and Melopsittacus) were found dead following natural infections. Natural infections of highly patho-genic avian influenza viruses (HPAIV) of the haemagglutinin subtypes H5 and H7 cause severe disease and high rates of mortality. Experimental transmission studies with AIVs of the subtypes H5 and H7 confirm these data. Viruses of the subtypes H3N8, H4N6, H4N8, Hl 1N6 and Hl 1N8 may cause also clinical signsand occasionally losses in naturally infected psittacine birds. Clinica signs and losses were also noted following experimental infection of budgerigars with a H4N6 virus.In the EU and in other countries, vaccination of exposed exotic and rare birds and poultry is a possible and an acceptable measure to provide protection. Currently, the EU Commission accepts inactivated adjuvanted vaccines whereas in some other countries recently developed vector vaccines are applied. However, birds remain susceptible during the time interval between application of any vac-cineand the development of immunity.This critical period can be bridged with antiviral drugs. Our in ovo studies demonstrate that the neuraminidase inhibitor oseltamivir is non-toxic forchicken embryos at concentrations of 0.1,1.0 and 10.0 mg/kg body weight.These dosages prevented entirely the replication ofa HPAIV of the subtype H7N1 when this drug is given shortly priorto, simultaneously or soon after inoculation ofchicken embryos with this AIV. Thus, we speculate that exposed valuable birds such as psittacines at riskcan be successfully treated.  a0341-6593