Assessing the Changes of Mumps Characteristics with Different Vaccination Strategies Using Surveillance Data: Importance to Introduce the 2-Dose Schedule in Quzhou of China

Abstract

Background. From 2005 to 2016, the prevention and control of mumps in China have undergone three stages of transition. These include the use of MuCV as a self-supported vaccine, the introduction of one-dose MMR to the Expanded Program on Immunization (EPI), and the administration of two-dose MuCV following supplementary immunization activities (SIAs) using MM. Here, using surveillance data, we assessed the epidemiology of mumps during the three stages. Methods. Children in Quzhou of China born from 2005 to 2016 and registered in the Zhejiang Provincial Immunization Information System (ZJIIS) were included. We analyzed the epidemic data and calculated incidence and MuCV coverage via birth cohorts. Results. The average incidence of mumps in 2005-2006, 2007-2010, and 2011-2016 was 51.57, 41.02, and 12.53 per 100,000 individuals, respectively. The highest incidence was in children aged 6-14 years from 2005-2016, of which the majority were school students (67.84%). Approximately 90% of the reported outbreaks occurred in school children (primary school/middle school). The seasonal characteristics of mumps were less obvious from 2011 to 2016. The coverage of one-dose MMR in the 2005 birth cohort was 71.38%. For the 2006-2010 birth cohort, the coverage of one-dose MuCV was 96.82% and the coverage of two-dose MuCV was 17.68%. The children born from 2011 to 2016 were only free vaccinated with MMR; the coverage of one-dose MuCV was 99.10%. The mumps incidence in the three birth cohorts significantly declined (X2=805.90, P<0.001 for trend). Except the children less than two years old, the mumps incidence for the children born from 2006 to 2010 was higher than that for the children born from 2011 to 2016. Conclusion. The mumps incidence significantly declined following the introduction of one-dose MMR. The SIA using MM led to a rapid reduction of mumps cases. Therefore, we recommend a two-dose MuCV routine immunization schedule and improved vaccination coverage.

A Multi-Age-Group Interrupted Time-Series Study for Evaluating the Effectiveness of National Expanded Program on Immunization on Mumps

“…In practice, although the EPI-MMR was introduced in Guangzhou in September 2008, the number of mumps cases was not brought under control quickly and effectively. After a few years, it began to display a downward trend, similar to the situation observed in the whole of China, and in some other cities [ 28 , 29 , 30 , 31 ]. The reason for this is that from 2008–2011, only children aged 2–5 years were the target population of the EPI, while all children above five years are at high risk of mumps.…”

“…Some descriptive epidemiological approaches indicated the effectiveness of the EPI-MMR, although they failed to accurately quantify the effect of the intervention [ 30 , 31 , 33 ]. Some studies offered a third dose of MMR vaccine to some eligible students and calculated mumps incidence rates for specific periods, before and after the intervention [ 34 , 35 ].…”

Epidemiological characteristics of mumps from 2004 to 2020 in Jiangsu, China: a flexible spatial and spatiotemporal analysis

“…In addition, the effectiveness of single-dose MMR vaccine is not so ideal. Several studies have reported that the protective effect of MuCV diminishes over time and declines rapidly by the 5th year after vaccination [ 38 , 39 ]. It may be the comprehensive reasons of these economic, meteorological and, vaccine factors that explain the northward movement of mumps hotspot clusters.…”

Assessment of mumps-containing vaccine effectiveness by dose during 2006 to 2020 in Quzhou, China

“… 6 Despite the high vaccination rate of MMR in Quzhou, 8,525 mumps cases were reported from 2005 to 2016, with more than 1,839 mumps cases reported in 2009. 7 From September to December in 2010, supplementary immunization activity (SIA) using measles mumps (MM) was performed in Zhejiang province. The children born from 1 October 2005 to 31 December 2009 would receive one dose of MM free of charge, whether they were local or migrant children, and with or without a history of MuCV.…”