RESUMEN
Trivalent oral poliovirus vaccine (tOPV) has been withdrawn and instead an inactivated poliovirus vaccine (IPV) and bivalent type 1 and type 3 OPV (bOPV) sequential immunization schedule has been implemented since 2016, but no immune persistence data are available for this polio vaccination strategy. This study aimed to assess immune persistence following different polio sequential immunization schedules. Venous blood was collected at 24, 36, and 48 months of age from participants who had completed sequential schedules of combined IPV and OPV in phase III clinical trials. The serum neutralizing antibody titers against poliovirus were determined, and the poliovirus-specific antibody-positive rates were evaluated. A total of 1104 participants were enrolled in this study. The positive rates of poliovirus type 1- and type 3-specific antibodies among the sequential immunization groups showed no significant difference at 24, 36, or 48 months of age. The positive rates of poliovirus type 2-specific antibody in the IPV-IPV-tOPV group at all time points were nearly 100%, which was significantly higher than the corresponding rates in other immunization groups (IPV-bOPV-bOPV and IPV-IPV-bOPV). Immunization schedules involving one or two doses of IPV followed by bOPV failed to maintain a high positive rate for poliovirus type 2-specific antibody.
RESUMEN
OBJECTIVE: To investigate the epidemiological characteristics of mumps in mainland China from 2004 to 2018, and to provide data for the key population for prevention and control of mumps. METHODS: The epidemiological characteristics of mumps were analyzed with reference to the data of the cases of mumps reported in the National Scientific Data Sharing Platform for Population and Health and Disease Prevention and Control Bureau of National Health Commission of the People's Republic of China. Descriptive epidemiology was used to analyze the epidemiological characteristics of mumps. RESULTS: A total of 4 272 368 cases of mumps were reported in China during 2004-2018, with an average annual reported incidence rate of 21.44/100 000. A single dose of mumps-containing vaccine was added to the national Expanded Program of Immunization in 2008, but the annual incidence rate ranged from 12.84/100 000 to 35.59/100 000. The second dose of measles, mumps and rubella combined attenuated live vaccine was included in the routine immunization in Beijing, Tianjin and Shanghai, and then the average incidence rate of mumps reported in these three regions dropped to about 10/100 000. From 2004 to 2016, the population aged 3-14 years accounted for 81.16% of all patients with mumps. The children aged 6 years had the highest incidence rate of mumps during 2004-2013. CONCLUSIONS: A single dose of mumps-containing vaccine has no obvious effect on the incidence rate of mumps. Children aged 6 years have the highest incidence rate of mumps. A booster dose of mumps-containing vaccine should be given to preschool children.
