Measles incidence and reporting trends in Germany, 2007–2011

Abstract

ObjectiveWe aimed to quantify progress towards measles elimination in Germany from 2007 to 2011 and to estimate any potential underreporting over this period.MethodsWe determined the annual incidence of notified cases of measles – for each year – in northern, western, eastern and southern Germany and across the whole country. We then used measles-related health insurance claims to estimate the corresponding incidence.FindingsIn each year between 2007 and 2011, there were 6.9–19.6 (mean: 10.8) notified cases of measles per million population. Incidence decreased with age and showed geographical variation, with highest mean incidence – 20.3 cases per million – in southern Germany. Over the study period, incidence decreased by 10% (incidence rate ratio, IRR: 0.90; 95% confidence interval, CI: 0.85–0.95) per year in western Germany but increased by 77% (IRR: 1.77; 95% CI: 1.62–1.93) per year in eastern Germany. Although the estimated incidence of measles based on insurance claims showed similar trends, these estimates were 2.0- to 4.8-fold higher than the incidence of notified cases. Comparisons between the data sets indicated that the underreporting increased with age and was generally less in years when measles incidence was high than in low-incidence years.ConclusionGermany is still far from achieving measles elimination. There is substantial regional variation in measles epidemiology and, therefore, a need for region-specific interventions. Our analysis indicates underreporting in the routine surveillance system between 2007 and 2011, especially among adults.

Perspective on Global Measles Epidemiology and Control and the Role of Novel Vaccination Strategies

“…One known limitation in measles case surveillance is that it is subject to underreporting. Studies have demonstrated underreporting in outbreak settings; one study in Germany demonstrated an average of three times lower rates of reporting to the mandatory notification system compared to health insurance claim submissions by doctors [ 45 , 46 ]. The Measles Strategic Planning (MSP) tool developed by the WHO for the analysis of immunization and surveillance data at a national level, also demonstrates underreporting in non-outbreak settings in countries across the globe [ 47 ].…”

Epidemiology and economic burden of measles, mumps, pertussis, and varicella in Germany: a systematic review

“…Outbreak-related incidence estimates ranged between 12 and 32 per 100,000 inhabitants. One study examining the epidemiology of measles from 2007 to 2011 (Takla et al 2014) showed large geographical differences in incidence of measles with the highest incidence in southern Germany. Another study presenting results for 1999 to 2001 (Tischer et al 2002) found that most cases of measles occurred in southern Germany and in North Rhine-Westphalia.…”

“…Another study presenting results for 1999 to 2001 (Tischer et al 2002) found that most cases of measles occurred in southern Germany and in North Rhine-Westphalia. Two studies (Mette et al 2011; Takla et al 2014) compared results of the analyses of surveillance data and ASHIP claims data and found that incidence estimates based on ASHIP data were higher than estimates based on notification data. Some studies only reported absolute numbers of cases instead of presenting data as incidence rates (see Table 2 for details).…”

A national measles outbreak in Ireland linked to a single imported case, April to September, 2016

“…For example, Case E2 was most likely infected by an unknown intermediate case, who in turn was most likely infected by Case E1. The problem of under-reporting of measles has been acknowledged elsewhere [ 28 - 30 ].…”