Re-emerging, under-recognized zoonotic, and neglected tropical diseases in Hawaiʻi

Hawaiʻi, the United States’ most western geographic state in the Pacific, is intermediate between the North and South American continents and Indo-Pacific regions, including Japan. The Hawaiian Islands’ tropical environmental conditions provide favorable ecosystems for various infectious pathogens, their vectors, and reservoirs. This creates a conducive environment for-transmission of various zoonotic diseases that affect both humans and animals. Hawaiʻi has experienced an increase in outbreaks of dengue, leptospirosis, and murine typhus. Further, toxoplasmosis and neuroangiostrongyliasis cases remain prevalent throughout the state, and the putative presence of autochthonous Zika cases in a retrospective study may be of national public health concern. Understanding the factors that affect the transmission and distribution of zoonoses is necessary to identify at-risk places and populations. The One Health approach seeks to understand, report, and interpret these factors and requires collaborations between private and government institutions. One Health should focus its efforts on neglected tropical diseases (NTD) and prioritize intervention development to control and prevent the transmission of diseases that spread between animals and humans. This review will focus on the epidemiological and clinical characteristics of under-recognized zoonotic and NTD affecting Hawaiʻi: leptospirosis, murine typhus, neuroangiostrongyliasis, toxoplasmosis, dengue, and Zika infections.