The evolution, characterization and phylogeography of avian influenza H9N2 viruses from India.

The low pathogenic avian influenza H9N2 virus is a significant zoonotic agent and contributes genes to highly pathogenic avian influenza (HPAI) viruses. H9N2 viruses are prevalent in India with a reported human case. We elucidate the spatio-temporal origins of the H9N2 viruses from India. A total of 30H9N2 viruses were isolated from poultry and environmental specimens (years 2015-2020). Genome sequences of H9N2 viruses (2003-2020) from India were analyzed, revealing several substitutions. We found five reassortant genotypes. The HA, NA and PB2 genes belonged to the Middle-Eastern B sublineage; NP and M to the classical G1 lineage; PB1, PA and NS showed resemblance to genes from either HPAI-H7N3/H5N1 viruses. Molecular clock and phylogeography revealed that the introduction of all the genes to India took place around the year 2000. This is the first report of the genesis and evolution of the H9N2 viruses from India, and highlights the need for surveillance.

Serological surveillance and clinical investigation of glanders among indigenous equines in India from 2015 to 2018.

Equine glanders is an infectious and notifiable bacterial disease caused by Burkholderia mallei. The disease has been reported in South American, African and Asian countries including India. Here, we present the outcome of glanders serosurveillance carried out between January 2015 and December 2018 to know the status of equine glanders among different states in India. A total of 102,071 equid sera from 299 districts of twenty-one states and one union territory were tested for glanders. Samples were screened with Hcp1 indirect ELISA followed by confirmatory diagnosis by CFT. During this four-year surveillance, a total of 932 glanders-positive cases were detected from 120 districts of 12 states. The study also revealed increasing trend of glanders from 2016 onwards with maximum occurrence in northern India. Overall seroprevalence ranged between 0.62% (95% CI, 0.52-0.72) and 1.145% (95% CI, 1.03-1.25). Seasonal shifting from winter to summer (March to June) coincided with highest number glanders incidence with corresponding seroprevalences of 1.2% (95% CI, 1.09-1.30). The present surveillance unveils territorial ingression of glanders to six states like Jammu & Kashmir, Gujarat, Rajasthan, Madhya Pradesh, Delhi and Tamil Nadu. In addition, re-emerging cases have been reported in Maharashtra, Haryana and Punjab after a gap of 10 years. Lack of awareness, little veterinary care and unrestricted movement of equids across state borders might have led to the introduction and establishment of the infection to these states. We believe that information from this study will provide a baseline data on glanders for devising surveillance and control strategies in India. Being a zoonotic disease, the persistence of glanders poses a potential threat to occupationally exposed humans especially equine handlers and veterinarians. Therefore, targeted surveillance of human population from each glanders outbreak is also recommended.