Epidemic & Pandemic

Epidemic is an unexpected increase in the number of disease cases in a specific geographical area (CDC). A pandemic is the worldwide spread of a disease (WHO, 2021).

Epidemic, pandemic and biological disasters are caused by hazards of organic origin, including bacteria, viruses, parasites, mosquitoes carrying disease-causing agents, and toxins or bioactive substances that occur naturally or are deliberately or unintentionally released. These hazards can lead to economic and environmental damage and loss of life, affecting people and animals at the population level as well as crops, livestock and endangered species of flora and fauna.

Epidemic diseases infect millions every year, and the COVID-19 pandemic illustrates the breadth and depth of the transformative impact of biological disasters. According to the WHO, the pandemic cost more than 6.8 million lives between March 2020 and March 2023,  and sparked the deepest economic recession in decades. The 21st century has already experienced several major infectious disease epidemics – old diseases such as cholera and plague have returned, and new ones like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and H1N1 pandemic influenza have emerged. Further epidemics and pandemics are almost certain; the only unknowns are when and where a new lethal threat will emerge. Examples of other recent outbreaks, epidemics or pandemics include Ebola in the Democratic Republic of Congo (2018–2020) and West Africa (2013–2016), and the Zika virus in the Americas and Pacific regions (2015–2016).

Risk factors

Biological hazards are driven by a complex set of factors ranging from:

  • The ease of spread of biological hazards.
  • Exposure.
  • Susceptibility to becoming infected.
  • Capacity of individuals, communities, countries and international actors to reduce risks and manage the consequences of outbreaks.

Vulnerable areas

Biological hazards affect people at all levels of society and in all countries because

  • Infectious diseases travel easily across borders.
  • New pathogens continue to emerge by mutating, adapting and travelling from one species to another.
  • Biological hazards can be endemic, that is constantly present in a community – they pose low risk when the population is largely immune, but risk becoming epidemics when they are introduced to a new host community with no immunity.

Risk reduction measures

  • Ensure hospitals and health care can continue working when they are most needed.
  • Build resilient infrastructure.
  • Assess potential risks before planning and building hospital.
  • Have a hazard map to identify people at risk and their vulnerability.
  • Have a national or local plan in place to plan and anticipate.
  • Train staff on potential risks.
  • Install a monitoring system to predict and proceed to early evacuation.
  • Ensure contingency and response plans are in place at a national and local level to evacuate people on time.
  • Educate people and raise awareness on potential risks.

Other considerations

The HIV/AIDS pandemic, which has claimed more than 32 million lives since it was identified in 1981, shows how biological hazards often exploit the fault lines of society, spreading in the shadows of marginalization, disruption and conflict.

Droughts, floods, earthquakes and large displacements of populations also create conditions favourable for disease transmission.

Latest Epidemic & Pandemic additions in the Knowledge Base

A special report addresses the invisible threat of rising heat, looking at the issue from different angles such as urban heat, gains and losses, and disease and migration. The report also looks at innovative ways of keeping temperatures down from an individual to governmental level.
Thomson Reuters Foundation, trust.org
A new study has examined three different approaches to pandemic preparedness, concluding that a combination of them can result in the best preparation for the future. Thorough preparedness would enable rapid deployment of diagnostics, treatments, and vaccines, which might have the potential to stop an outbreak from becoming a pandemic.
National Institutes of Health
The new BBC Pandemic app anonymously collects data on how users travel and the number of persons they come into contact with during a 24 hour period. The data will then be used to simulate the spread of a highly infectious disease. The results will be presented in a documentary to be aired in spring 2018.
British Broadcasting Corporation (BBC)

With funding from the Swiss Federal Department of Defence, Civil Protection and Sport (DDPS), on 24–25 August 2016 the Geneva Centre for the Democratic Control of Armed Forces (DCAF) and the Global Health Centre (GHC) at the Graduate Institute in Geneva

Rising temperatures and urbanisation could spark vector-borne disease epidemics across Africa, scientists say. As temperatures rise, mosquito habitat ranges will change, leading to infections of diseases such as malaria and dengue in new areas. Climate data can be used to predict outbreaks and indicate risks, but better coordination is needed between African nations.
Thomson Reuters Foundation, trust.org
Following the flood and landslides in Freetown, Sierra Leone, immediate actions were taken to mitigate risks of outbreaks of infectious diseases. Healthcare workers were sent to detect, report, and treat cholera and other outbreak-prone diseases, and communities were engaged in disease prevention including handwashing and food hygiene.
World Health Organization Regional Office for Africa
Predicting how climate change will affect the incidence of infectious diseases would have great public health benefits. To do so, researchers need new statistical models that incorporate both climate factors and the climate-disease relationship, accounting for uncertainties in both. A new study looks at statistical techniques that can be used to model this relationship.
Princeton University
African Risk Capacity has launched an Outbreak & Epidemic (O&E) insurance product, which represents a significant improvement in the continent’s ability to protect against and respond to disease outbreaks and epidemics. In the pilot phase, Guinea and Uganda will be the first two countries to have the programme offered.
African Risk Capacity

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