Retrospective Studies: Excellent Tools to Complement Surveillance.

The article focuses on various retrospective studies conducted by researcher Takahashi and colleagues which discusses the efficacy of regional infectious disease surveillance networks to facilitate the implementation of international health organizations. Topics include relationship between the Japanese and Chinese viruses by phylogenetic analysis, diagnosis of severe fever with thrombocytopenia syndrome virus (SFTSV) and Lujo virus, and recent identification of Heartland virus in the U.S.