Case Based Measles Surveillance in Pune: Evidence to Guide Current and Future Measles Control and Elimination Efforts in India

Abstract

BackgroundAccording to WHO estimates, 35% of global measles deaths in 2011 occurred in India. In 2013, India committed to a goal of measles elimination by 2020. Laboratory supported case based measles surveillance is an essential component of measles elimination strategies. Results from a case-based measles surveillance system in Pune district (November 2009 through December 2011) are reported here with wider implications for measles elimination efforts in India.MethodsStandard protocols were followed for case identification, investigation and classification. Suspected measles cases were confirmed through serology (IgM) or epidemiological linkage or clinical presentation. Data regarding age, sex, vaccination status were collected and annualized incidence rates for measles and rubella cases calculated.ResultsOf the 1011 suspected measles cases reported to the surveillance system, 76% were confirmed measles, 6% were confirmed rubella, and 17% were non-measles, non-rubella cases. Of the confirmed measles cases, 95% were less than 15 years of age. Annual measles incidence rate was more than 250 per million persons and nearly half were associated with outbreaks. Thirty-nine per cent of the confirmed measles cases were vaccinated with one dose of measles vaccine (MCV1).ConclusionSurveillance demonstrated high measles incidence and frequent outbreaks in Pune where MCV1 coverage in infants was above 90%. Results indicate that even high coverage with a single dose of measles vaccine was insufficient to provide population protection and prevent measles outbreaks. An effective measles and rubella surveillance system provides essential information to plan, implement and evaluate measles immunization strategies and monitor progress towards measles elimination.

Measles in India: Challenges & recent developments

“…Until 2008, India was the only nation among the 193 member nations of the World Health Organization (WHO) to make provision for only a single dose of measles vaccine in their national immunization schedule, whereas all other nations opted for two doses of measles vaccine ( 22 ). In fact, in case-based measles surveillance in Pune, it was observed that, in approximately 40% of confirmed measles cases, the patient acquired the disease despite being immunized with one dose of measles vaccine; thus a single dose of measles vaccine was insufficient to protect the general population ( 23 ). Eventually, in response to the recommendations made by the Indian National Technical Advisory Group on Immunization and the findings of other studies, the government of India introduced a recommendation for a second dose of measles in late 2010 for all children between 16 and 24 months of age ( 12 , 24 , 25 ).…”

“…In addition, sensitizing health professionals to the need to conduct measles outbreak-based surveillance in all of the states and union territories of India can also assist in reducing the incidence of the disease ( 27 ). Further, crucial evidence can be obtained by undertaking case-based measles surveillance activities across all settings using the standardized guidelines proposed by the Government of India ( 23 , 28 ).…”

Reluctance to Advance the Age of Measles Immunisation: Ethics of Best Bargain, Policies of Denial, and Programs of Verticality

“…This argument is supported by a mathematical model of the impact of antibody level on seroconversion and immunity while estimating measures of protection among vaccinees (percentage of susceptibles, number of reported cases, percentage of lifetime spent susceptible) [10]. The importance of MCV2 coverage has again been highlighted in a recent report from India which demonstrated high measles incidence and frequent outbreaks inspite of above 90% MCV1 coverage [11]. There may be several reasons behind this, ranging from immunological to operational.…”

Measles occurrence, vaccination coverages and malnutrition in India: correlations, trends, and projections by time series analysis

“…Initially aggregate (outbreak-based) surveillance was established in the morbidity and mortality reduction phase, which was later converted into case-based surveillance system supported by a network of high quality laboratories accredited by WHO. [26][27][28] On 13 September 2013 in New Delhi, countries of WHO South-East Asia Region (SEAR) including India committed to eliminate measles and control rubella/congenital rubella syndrome (CRS) by 2020. The resolution was approved during the Sixty-sixth Regional Committee.…”