Characterization of Avian Influenza and Newcastle Disease Viruses from Poultry in Libya

Abstract

On March 2013, the Libyan poultry industry faced severe outbreaks due to mixed infections of APMV-1 (Newcastle disease) and low pathogenic avian influenza (AI) of the H9N2 subtype which were causing high mortality and great economic losses. APMV-1 and H9N2 were isolated and characterized. Genetic sequencing of the APMV-1/chicken/Libya/13VIR/ 7225-1/2013 isolate revealed the presence of a velogenic APMV-1 belonging to lineage 5 (GRRRQKR*F Lin.5) or genotype VII in class II, according to the nomenclature in use. Three AI viruses of the H9N2 subtype, namely A/avian/Libya/13VIR7225-2/2013, A/avian/Libya/13VIR7225-3/2013, and A/avian/Libya/13VIR7225-5/2013, were isolated and found to belong to the G1 lineage. Analysis of amino acid sequences showed that the analyzed H9N2 viruses contained the amino acid Leu at position 226 (H3 numbering) at the receptor binding site of the HA, responsible for human virus-like receptor specificity. On March 2014, an outbreak of highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was diagnosed in a backyard poultry farm in an eastern region of Libya. The H5N1 isolate (A/chicken/Libya/14VIR2749-16/2014) was detected by real time RT-PCR (rRT-PCR). Genetic characterization of the HA gene revealed that the identified subtype was highly pathogenic, belonged to the 2.2.1 lineage, and clustered with recent Egyptian viruses. This study revealed the presence of a velogenic APMV-1 genotype and of two influenza subtypes, namely HPAI H5N1 and H9N2, which are of major interest for public and animal health. Considering these findings, more investigations must be undertaken to establish and implement adequate influenza surveillance programs; this would allow better study of the epidemiology of APMV-1 genotype VII in Libya and evaluation of the current vaccination strategies.

New real time and conventional RT-PCRs for updated molecular diagnosis of infectious bronchitis virus infection (IBV) in chickens in Egypt associated with frequent co-infections with avian influenza and Newcastle Disease viruses

“…Velogenic NDV circulating among chickens in Egypt resembles genotype VIId (Chicken/China/SDWF07/2011) and is associated with outbreaks in commercial poultry farms despite adherence to strict vaccination regimes (Radwan et al, 2013). Similar co-infections of avian influenza and velogenic NDV were observed also in neighboring countries such as Jordan and Libya (Kammon et al, 2015;Roussan et al, 2008). In addition, a recent similar single case was reported in Egypt (Hussein et al, 2014).…”

Biosecurity Strategies for Backyard Poultry: A Controlled Way for Safe Food Production

“…Similarly in Libya, HPAI-H5N1 belonged to 2.2.1 lineage having similarities with Egyptian isolates. It was detected in backyard flocks (Kammon et al, 2015).…”

Newcastle disease in Nigeria: epizootiology and current knowledge of circulating genotypes

“…Although, the presence of the genotype has been established elsewhere in Africa, namely; Egypt [88], Libya [51], Sudan [42], South Africa [1], Mozambique [35], and Ethiopia [33].…”