Analysis of mumps antibody levels and mumps virus genotypes in Guilin City in 2015

Objective To determine mumps antibody levels and mumps virus genotypes in Guilin city in 2015 and provide a scientific basis for controlling mumps. Methods Immunoglobulin G (IgG)antibody of mumps patients were detected by enzyme-linked immunosorbent assay (ELISA). Small MuV hydrophobic protein gene was genotyped in pharyngeal swab of mumps patients using reverse transcription polymerase chain reaction (RT-PCR). Results The positive rate of mumps virus antibody in 263 cases of mumps in Guilin City was 81.75%. There were no significant difference in the positive rate of mumps virus antibody between different age groups (χ²=1.71, P=0.668),but there were significant difference in the level of mumps virus antibody between different age groups(H=14.16, P=0.003). There were no significant difference in the positive rate of mumps virus antibody between males and females (χ²=2.83, P=0.092), but the level of mumps virus antibody between males and females were significantly different (Z=-2.55, P=0.011). There were no significant differences in antibody positive rates and antibody levels of mumps virus among three groups of patients with epidemic parotitis (χ²=4.61, P=0.100; H=1.85, P=0.413). 25 strains of mumps virus were isolated from the 263 pharyngeal swabs of patients, which are all F genotypes. Conclusions The immune level of mumps in infants and young children in Guilin City is low. The incidence rate of mumps in males is higher than that in females in Guilin. The main type of mumps virus is F genotype.