Serologic Evidence of Avian Influenza H9N2 and Paramyxovirus Type 1 Infection in Emus (Dromaius novaehollandiae) in India

Important Findings An avian influenza (AI) surveillance was undertaken in Maharashtra state, India, during the period 2010–2011 (Figure 1). There are no reports of AI surveillance in emus from India. A total of 202 blood samples and 467 tracheal and cloacal swabs were collected from eight emu farms. A total of 28.2% and 28.7% samples were positive for antibodies against AI H9N2 by hemagglutination inhibition (HI) and microneutralization (MN) assays respectively using $ 1:40 as cut-off titer; 15.3% samples were positive for avian paramyxovirus type 1 (APMV-1) by HI assay using $ 1:10 cut-off titer. Seropositivity of AI H9N2 was nil in grower (,1 year) age group, was highest (78%) in breeder (2–3 year) age group, whereas seropositivity against APMV-1 was observed in all age groups. Performance of both HI and MN assays was similar, suggesting the utility of using the MN assay along with HI assay for surveillance studies. This is the first report of the seroprevalence of AI H9N2 and APMV-1 in emus in India.