Seroepidemiological investigation of measles among residents in Quzhou City / 预防医学

ABSTRACT

Objective@#To investigate the measles antibody level among residents in Quzhou City, Zhejiang Province in 2018, so as to provide the evidence for improving the measles control strategy.@*Methods@#The permanent residents aged 0 to 59 years were randomly sampled from 10 townships ( streets ) in Kecheng District and Changshan County of Quzhou City. Residents' demographics and vaccination of measles-containing vaccine ( MCV ) were collected, and serum anti- measles IgG antibody was detected using enzyme-linked immunosorbent assay ( ELISA ). The positive rate, protective rate and geometric mean concentration (GMC) of anti-measles antibody were estimated. @*Results@#A total of 606 residents were tested, with a male to female ratio of 0.83∶1. The subjects had a median age ( interquartile range ) of 17.36 ( 29.07 ) years, and 399 residents ( 65.84% ) had a vaccination history of MCV. The positive rate, protective rate and GMC of anti-measles IgG antibody were 94.88%, 48.68%, and 784.51 ( 95%CI 731.14-841.40) mIU/mL, respectively. The positive rate of anti-measles IgG antibody was higher in men than in women ( 97.08% vs. 93.07%, χ2=4.968, P=0.026 ), and the protection rate was lower in men than in women ( 44.16% vs. 52.41%, χ2=4.089, P=0.043 ). The protective rate and GMC of anti-measles IgG antibody showed a“U”-shaped distribution with age, and a low protective rate was seen in residents aged 10 to 39 years ( 23.53% to 46.67% ), which the GMC of anti-measles IgG antibody that did not reach the protective level. A total of 233 residents at age of 15 years and below had with a history of two-dose MCV vaccination, and the positive rate ( χ2trend=7.260, P=0.007 ), protective rate ( χ2trend=12.756, P<0.001 ) and GMC ( rs=-0.289, P<0.001 ) of anti-measles IgG antibody presented a tendency towards a reduction with time <1 to 11 years after vaccination of the last dose of MCV.@*Conclusions@#A high positive rate of anti-measles antibody was detected among residents in Quzhou City in 2018; however, the protection rate of anti-measles antibody was low among residents at ages of 10 to 39 years. The coverage of MCV vaccination is recommended to be improved among residents at ages of 10 to 39 years in Quzhou City.