Hemagglutinin-neuraminidase sequence and phylogenetic analyses of mumps virus isolates from a vaccinated population in Singapore

• Published in: Journal of medical virology Vol. 70; no. 2; pp. 287 - 292
• Main Authors: Lim, C.S., Chan, K.P., Goh, K.T., Chow, Vincent T.K.
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc., A Wiley Company 01-06-2003; Wiley-Liss
• Subjects: Amino Acid Sequence; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Genetics; HN gene; HN Protein - chemistry; HN Protein - genetics; Human viral diseases; Humans; Infectious diseases; Medical sciences; Microbiology; Molecular Sequence Data; Mumps - virology; Mumps Vaccine - administration & dosage; mumps virus; Mumps virus - classification; Mumps virus - genetics; Mumps virus - isolation & purification; Parotitis - virology; Phylogeny; Polymerase Chain Reaction; Rubini vaccine failure; Sequence Analysis, DNA; Singapore; Treatment Failure; Tropical medicine; Vaccination; Viral diseases; Viral diseases of the respiratory system and ent viral diseases; Virology; Asia; Singapore; Human; Genetic variability; Enzyme; Hemagglutinin; Glycoprotein; Genotype; Phylogeny; Paramyxoviridae; Infection; Virus; Paramyxovirinae; Mononegavirales; Glycosidases; Viral disease; Exo-α-sialidase; Rubulavirus; Hydrolases; Mumps; Mumps virus; O-Glycosidases; Clinical isolate
• ISSN: 0146-6615; 1096-9071
• DOI: 10.1002/jmv.10393

During 1999–2000, a sustained mumps outbreak in the highly vaccinated population in Singapore was attributed to vaccine failure associated with the Rubini vaccine strain. To explain this phenomenon, the complete nucleotide and amino acid sequences of the hemagglutinin‐neuraminidase (HN) gene of eight mumps virus isolates from patients with parotitis in Singapore were determined and compared with those of known vaccine strains. Phylogenetic trees constructed on the basis of HN nucleotide and amino acid sequences showed that the Singapore mumps virus isolates were more closely related to the Urabe strain and belonged to a different cluster from the Rubini and Jeryl‐Lynn strains. The Rubini vaccine showed only ∼93% nucleotide and ∼96% amino acid sequence similarity to Urabe and Singapore isolates. Compared with the vaccine strains, six of the eight isolates lacked the extracellular glycosylation site at residues 400–402. Other significant amino acid disparities (e.g., at residue 354) may also affect the antigenic properties of the HN protein. These findings suggest that the evolution and adaptation of the currently circulating mumps virus strains in the community has led to the emergence of genetically distinct viral strains. The low vaccine efficacy of the Rubini strain represents a major reason for the recent mumps resurgence and failure of mumps immunization in Singapore. J. Med. Virol. 70: 287–292, 2003. © 2003 Wiley‐Liss, Inc.