Evaluation of Lab-based Influenza Surveillance System in Pakistan, 2017

Background: Influenza is a common respiratory disease in Pakistan. However, the absence of a robust surveillance system makes it difficult to estimate the burden of disease. Purpose: We conducted this study to identify key strengths and weaknesses of the laboratory-based influenza surveillance system in Pakistan and to make recommendations for improvement. Methods: We conducted an evaluative descriptive study of the national laboratory-based influenza surveillance system from April to July 2017. We conducted this assessment using the updated guidelines for evaluating public health surveillance systems issued by CDC in 2011. Findings: The system was found to be simple and easy to operate, but with little flexibility to integrate with other pathogens and diseases. Data quality was good, given that 80% of observed forms were completed. Timeliness was good, as it takes only 24-48 hours from sample collection to report a submission to the central level. Acceptability was good, since both private and public sector hospitals and labs are involved. Sensitivity was 62% and positive predictive value (PPV) was 37.2%. The representativeness of lab based influenza surveillance system was poor, since it is a sentinel surveillance system with specific, strategically placed reporting sites. Conclusions: The system meets its objectives. Sustainability and stability of the system needs to be improved by allocation of public funds. Coverage of the system should be expanded to improve representativeness. Regular capacity building with staff at reporting sites will ensure continued quality of reporting.