Nudges to Promote Infectious Disease Case Reporting

Under Japan’s Infectious Diseases Control Law, physicians are required to report cases of specified infectious diseases; however, concerns remain that reporting is not conducted accurately, leading to incomplete surveillance. This study examines the actual status of case reporting and identifies bottlenecks in the reporting process through an online survey of physicians, focusing on syphilis, viral hepatitis, acute flaccid paralysis, acute encephalitis, invasive pneumococcal disease, and streptococcal toxic shock syndrome. The results show that reporting rates are low, mainly due to insufficient awareness of reporting obligations and penalties. Reporting rates are significantly lower among physicians aged 50 and over and those with low awareness of reporting obligations, while they are significantly higher among physicians working at sentinel medical institutions and those using electronic medical records. A randomized controlled trial (RCT) demonstrates that nudges temporarily increase the intention to report cases, but the effect largely disappears after three months. To improve reporting rates, it is necessary to clearly state reporting obligations on laboratory test reports and to implement regular awareness-raising activities.