

What is the Hazard?
Disease X
Unknown emerging diseases with epidemic potential are often referred to as “Disease X.” Disease X refers to a pathogen that hasn’t been discovered yet, but which is almost certain to cause a future global epidemic. Because so much is unknown about the next Disease X, countermeasures are insufficient – or don’t exist at all.
In 2018, the World Health Organization (WHO) included Disease X on its list of priority diseases for vaccine development. According to the WHO, “Disease X represents the knowledge that a serious international epidemic could be caused by a pathogen currently unknown to cause human disease, and so the [Research & Development (R&D)] Blueprint explicitly seeks to enable cross-cutting R&D preparedness that is also relevant for an unknown “Disease X”.” Similarly, the City’s efforts to prepare for and respond to disease outbreaks are designed to be as flexible and adaptable as possible for an unknown “Disease X.”
Large-scale release of biological threat without readily available medical countermeasures
This hazard includes the large scale release of a biological threat without readily available medical countermeasures. This includes biological weapons and the release of a novel or altered pathogen from a laboratory. Regardless of whether the release is accidental or intentional, the impact on the public’s health and corresponding response operations in the face of an unknown agent are the same. Both scenarios may result in mental health stress caused by an unknown agent, and reliance on strategies like quarantine and social distancing in the absence of countermeasures. Quarantine requirements in a large scale incident can overwhelm the healthcare system and the societal disruption caused by social distancing can impede a community’s ability to cope.
Contributors to the Public Health Severity of a Hazard, by Weight
Severity Contributors | Weight |
---|---|
Severe injuries and an increase in illness | 15.5% |
Deaths | 15.0% |
Risk of an associated disease outbreak | 13.4% |
Disruption to the potable water supply | 12.1% |
Increase in harmful or life-threatening toxic exposures and environmental contamination | 10.0% |
Loss of utility-provided power | 9.7% |
Diminished capacity of the healthcare system | 9.2% |
Food scarcity | 7.7% |
Disruption of communication systems | 7.5% |
Contributors to Estimating the Probability of a Public Health Hazard, by Weight
Probability Contributors | Weight |
---|---|
Changes in the environment or threat landscape that makes it more likely to occur | 38.0% |
Forecast models and academic or actuarial studies | 23.4% |
An increasing frequency of similar events | 23.2% |
The number of reported occurrences | 15.3% |
Previous Emerging Diseases with Epidemic Potential
Year | Emerging Disease |
---|---|
1981 | AIDS emergence (US awareness) |
1992 | Tuberculosis resurgence in NYC |
1999 | West Nile Virus enters NYC |
2013 | Chikungunya enters the Americas |
2014 | Ebola in NYC |
2014 | Legionnaires in NYC |
2015 | Zika enters the US |