Abstract:
Objective To analyze the epidemic characteristics of measles and rubella in Pudong New Area of Shanghai from 2013 to 2022, and to provide data support for the elimination of measles and rubella.
Methods Enzyme linked immunosorbent assay was used to detect IgM antibodies in serum samples. The sequence of 630 nucleotides at the C-terminal of N gene of measles virus was amplified by reverse transcription-polymerase chain reaction and the phylogenic tree was constructed.
Results A total of 1 529 suspected cases of measles were detected from 2013 to 2022, among which the positive rate of measles IgM antibody was 33.55% (513/1 529). The highest positive rate (20.73%) was from March to May, and the positive rate of rubella IgM antibody was 6.80% (104/1 529). The positive rate of both IgM was higher in males than that in females (P<0.05). The IgM against measles was mainly detected in 0‒ years old (63.16%, 96/152) and 20‒ years old (45.61%, 161/353). The IgM against rubella was mainly detected in 10‒20 years old (27.27%, 18/66). The IgM antibody could be detected more easily from 4 to 28 days after eruption, and the IgM antibody positive rate of measles/rubella from 2020 to 2022 was significantly lower than previous years (2013‒2019). There were 2 D8 genotype strains, and the rest were H1a gene subtypes.
Conclusion The positive rate of IgM antibodies against measles/rubella in Pudong New Area of Shanghai decreased significantly. People aged 0‒ years and 20‒ years old are more susceptible to measles, and rubella is concentrated in 10‒ years old. It is necessary to strengthen the vaccination of school-age children, in order to achieve the goal of eliminating measles. The age group with high risk of exposure should be checked for vaccination status to ensure the enhanced immunization, and the surveillance of imported measles cases should be strengthened.