The case for investing in public health surveillance in low- and middle-income countries.

Surveillance is central to public health. In the absence of comparable data from most low-income and middle-income countries, national and international agencies use estimates to monitor health targets. Although morbidity and mortality estimations generated by statistical modelling can fulfill national and global reporting requirements, locally generated data are needed to guide evidence-based local action. The focus on measurement around the sustainable development goals provides an opportunity for WHO and the global health community to make a case for increased investment by governments to strengthen local surveillance systems.