RT-PCR based diagnosis and molecular characterisation of mumps viruses derived from clinical specimens collected during the 1996 mumps outbreak in Portugal.

Clinical specimens collected during an outbreak of mumps were characterised by RT-PCR, nested PCR, and nucleotide sequencing. Mumps virus was positively identified in 12/21(57%) saliva, 9/21(43%), throat and 1/33(3%) urine specimens and further sequence comparison revealed that at least six strains of viruses, which differed from 0-9.43% at the nucleotide levels, were cocirculating during the epidemic. However, phylogenetic analysis showed that these viruses grouped with two previously identified lineages which were mostly composed of other European mumps virus isolates.