What is a Hotspot Anyway?

Abstract

The importance of spatial clusters, or “hotspots,” in infectious disease epidemiology has been increasingly recognized, and targeting hotspots is often seen as an important component of disease-control strategies. However, the precise meaning of “hotspot” varies widely in current research and policy documents. Hotspots have been variously described as areas of elevated incidence or prevalence, higher transmission efficiency or risk, or higher probability of disease emergence. This ambiguity has led to confusion and may result in mistaken inferences regarding the best way to target interventions. We surveyed the literature on epidemiologic hotspots, examining the multitude of ways in which the term is used; and highlight the difference in the geographic scale of hotspots and the properties they are supposed to have. In response to the diversity in the term's usage, we advocate the use of more precise terms, such as “burden hotspot,” “transmission hotspot,” and “emergence hotspot,” as well as explicit specification of the spatiotemporal scale of interest. Increased precision in terminology is needed to ensure clear and effective policies for disease control.

Persistent Hotspots in Schistosomiasis Consortium for Operational Research and Evaluation Studies for Gaining and Sustaining Control of Schistosomiasis after Four Years of Mass Drug Administration of Praziquantel

“…Spatial clusters or hotspots have been recognized in infectious disease epidemiology in various contexts to describe an area of higher burden of disease or higher transmission of disease. 13 For instance, malaria transmission is known to be higher in hotspots, and it is recognized that elimination of these residual foci will be necessary for malaria elimination. [14][15][16][17] Studies of schistosomiasis programs also show that some communities remain at persistently high prevalence despite MDA.…”

Ethical Considerations for Movement Mapping to Identify Disease Transmission Hotspots

“…We see 2 highly relevant ethical obstacles: protecting the participants’ privacy in relation to principles of autonomy and nonmaleficence and finding a balance between costs, risks, and benefits for participants and communities in relation to principles of beneficence and justice ( 11 ). …”

“…Human behavior, particularly movement between locations, plays a primary role in the transmission dynamics of infectious diseases ( 1 ). Geospatial areas with high prevalence or efficient transmission of disease are known as hotspots ( 2 ). Transmission hotspots can be thought of as nodes in space and time where the density of contact between infected and uninfected persons is higher than average, increasing the risk for disease transmission.…”

Identifying hotspots of viral haemorrhagic fevers in the Eastern Mediterranean Region: perspectives for the Emerging and Dangerous Pathogens Laboratory Network

“…Although today there are a number of published tools to guide the process of setting priorities, only a few publications describe the methodology in sufficient detail and transparency to allow reproducibility or adaptation in other settings (7)(8)(9). The concept of hotspots in infectious disease epidemiology varies widely in current research, and may include aspects, such as incidence or prevalence, transmission efficiency or risk, or probability of disease emergence (10). For our study, the objective was neither to assess socioeconomic level nor health system capacity, but rather the disease burden and its potential transmission in order to compare multiple diseases between multiple countries.…”