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

Documents and publications

This publication outlines the health sector's role in reducing the impact of disasters, laying out a framework that an administrator can rely on to make effective decisions in managing the health sector''s activities to reduce the consequences of

Documents and publications

This report will attempt to catalogue and briefly discuss the immediate medical and long-term health effects of a natural disaster. Other topics such as the disruption of a community’s critical infrastructure, vulnerable groups within populations, and

Documents and publications

According to the International Federation of the Red Cross and Red Crescent Societies, in 2002, international disasters affected 608 million people and killed more than 24,000. Disasters are unusual public health events that overwhelm the coping capacity

Documents and publications

This strategic plan is designed to contribute to human well-being, minimizing the negative effects of disasters and other crisis by responding to the health needs of vulnerable populations affected by such events. It focuses on strengthening the

Documents and publications

A PowerPoint presentation at the South Asia Policy Dialog Workshop, New Delhi, India 21-22 August 2006.

Documents and publications

This detailed report analyzes El Salvador overall situation before the 2001 earthquake and assesses the effects of the disaster, specifically for the health services and for the salubrity of the environment. It also considers the management of the

photo thanks to Walter Hays
Update
Mr. Yasuo Fukuda called on Asia-Pacific nations to jointly build a network to better prepare for disasters and pandemics....
Xinhua News Agency
Documents and publications

Illustrated with examples from recent research in the field, this book summarizes the most pertinent and useful information about the public health impact of disasters. It is divided into four sections dealing with general issues, geophysical events

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