Outbreak of influenza-like illness investigated during August 2013 near Indo-China border of Arunachal Pradesh, Northeast India.

ABSTRACT

During August 2013, an outbreak of influenza-like illnesses (ILI) was investigated in Monigong area, near Indo-China border of Arunachal Pradesh, Northeast India. Influenza type A/H3N2 was detected by RT-PCR in 33.3% (8/24) of ILI cases. Sequence analysis of HA and NA genes revealed eight and five amino acid substitutions, respectively in Monigong H3N2 (Mo/H3N2) strains as compared to vaccine strain A/Victoria/361/2011. Four non-synonymous substitutions, three localizing at antigenic sites T144A, A; R158G, B; L173S, D, and one H9Y in close proximity to a potential glycosylation site aa8 in HA1 domain along with the substitution T329N in NA are likely to influence the antigenicity/virulence of Mo/H3N2 viruses. J. Med. Virol. 881999-2003, 2016. © 2016 Wiley Periodicals, Inc.