The Surveillance of Chikungunya Virus in a Temperate Climate: Challenges and Possible Solutions from the Experience of Lazio Region, Italy

Abstract

CHIKV has become an emerging public health concern in the temperate regions of the Northern Hemisphere as a consequenceof the expansion of the endemic areas of its vectors (mainly Aedes aegypti and Aedesalbopictus). In 2017, a new outbreak of CHIKV was detected in Italy with three clusters of autochthonous transmission in the Lazio Region (central Italy), in the cities of Anzio, Rome, and Latina and a secondary cluster in the Calabria Region (south Italy). Given the climate characteristics of Italy, sporadic outbreaks mostly driven by imported cases followed by autochthonous transmission could occur during the summer season. This highlights the importance of a well-designed surveillance system, which should promptly identify autochthonous transmission. The use of a surveillance system integrating different surveillance tools, including entomological surveillance in a one health approach, together with education of the health care professionals should facilitate the detection, response, and control of arboviruses spreading.

Keywords: Chikungunya; Italy; surveillance; temperate climate.

Figure 1

Number of Emergency Department (ED) admissions expected value and alert threshold for Chikungunya Virus (CHIKV) Syndrome. Blue Line, Expected number of ED admissions; Green Line, upper 95% confidence interval for the expected number of ED admissions (first alert threshold); Red Line, upper 99% confidence interval for the expected number of ED admissions (second alert threshold).

Figure 2

Number of ED admissions, expected value and alert threshold for Arthropod bites syndrome. Blue Line, Expected number of ED admissions; Green Line, upper 95% confidence interval for the expected number of ED admissions (first alert threshold); Red Line, upper 99% confidence interval for the expected number of ED admissions (second alert threshold).