Serological evidence of mixed infections with avian infl uenza and Newcastle disease in village chickens in Jigawa State, Nigeria

A serological survey for antibodies against avian infl uenza (AI) and Newcastle disease (ND) viruses in 250 village chickens confi rmed to be suffering from highly pathogenic avian infl uenza (HPAI) was carried out in Jigawa State, Nigeria. The chickens had no history of vaccination against the two diseases. Sera were tested by the haemagglutination inhibition (HI) test for the presence of antibodies against the two virus antigens. Antibody prevalence against the viruses was noted as follows: AI (31.6%) and ND (38.8%), with mean antibody titres of 0.32 ± 0.1 Log2 and 0.39 ± 0.2 Log2, respectively. The fi nding that 70.4 % of the sera examined contained HI antibodies to both virus antigens indicates considerable combined activities of the two viruses among the village chickens during the HPAI outbreaks. It is suggested that this group of scavenging birds may play signifi cant roles in the transmission of these two viruses to commercial poultry farms. The introduction and sustenance of routine vaccination of scavenging village poultry against ND is highly recommended. Nation-wide active surveillance of AI should also be conducted to defi ne the true status of the disease in poultry in Nigeria. Key words: antibodies, avian infl uenza, Newcastle disease, village chicken