Risk factors for measles in children aged 8 months-14 years in China after nationwide measles campaign: A multi-site case-control study 2012-2013.

Wednesday, 27th of April 2016

Vaccine. 2016 Feb 11. pii: S0264-410X(16)00131-6. doi: 10.1016/j.vaccine.2016.02.005. [Epub ahead of print]

Risk factors for measles in children aged 8 months-14 years in China after nationwide measles campaign: A multi-site case-control study 2012-2013.

Hao L¹ Ma C¹ Wannemuehler KA¹ Su Q¹ An Z¹ Cairns L¹ Quick L¹ Rodewald L¹ Liu Y¹ He H¹ Xu Q¹ Ma Y¹ Yu W¹ Zhang N¹ Li L¹ Wang N¹ Luo H¹ Wang H² Gregory CJ¹.

Author information

Abstract

INTRODUCTION:

Endemic measles persists in China despite >95% reported coverage of two measles-containing vaccine doses and nationwide campaign that vaccinated more than 100 million children in 2010. In 2011 almost half of the 9943 measles cases in China occurred in children eligible for measles vaccination. We conducted a case-control study during 2012-2013 to identify risk factors for measles infection in children aged 8 months-14 years.

METHODS:

Children with laboratory-confirmed measles were age- and neighborhood-matched with three controls. We interviewed parents of case and control infants on potential risk factors for measles. We calculated adjusted matched odds ratios and 95% confidence intervals of risk factors. We calculated attributable fractions for risk factors that could be interpreted as causal and vaccine efficacy (VE) for the measles containing vaccine (MCV) used in the Chinese immunization program.

RESULTS:

In all 969 case-patients and 2845 controls were enrolled. In multivariable analysis lack of measles vaccination both overall (mOR 22.7 [16.6 31.1] and when stratified by region (east region mOR 74.2 [27.3 202]; central/western regions mOR 17.4 [12.5 24.3]) hospital exposure (mOR 63.0 95% CI [32.8 121]) and migration among counties (overall mOR 3.0 [2.3 3.9]) were significant risk factors. The calculated VE was 91.9-96.1% for a single dose of MCV and 96.6-99.5% for 2 doses.

CONCLUSIONS:

Lack of vaccination was the leading risk factor for measles infection especially in children born since the 2010 supplementary immunization activity. Reducing missed vaccination opportunities improving immunization access for migrant children and strengthening school/kindergarten vaccine checks are needed to strengthen the routine immunization program and maintain progress toward measles elimination in China.

Copyright © 2016. Published by Elsevier Ltd.