Session 1.1. The importance of epidemics

By the end of this session, you will be able to: 

• Discuss why epidemics are important.
• Explain the broader impact of epidemics on societies.

In the course of human history, epidemics have been responsible for millions of deaths. During the plague epidemic in 541-542 AD, 100 million people died, half the human population at that time. In the plague epidemic between 1346 and 1350, Europe lost half its population. The “Spanish flu” epidemic in 1918 killed more men than the First World War. Epidemics are also common today. The “swine” flu in 2009 was responsible for 200,000 deaths, and more than 11,000 people died in an Ebola epidemic in 2014. In 2017 alone, outbreaks of plague occurred in Madagascar and the Seychelles, of Middle East respiratory syndrome in Saudia Arabia, of coronavirus disease in Saudi Arabia, Oman and the United Arab Emirates, of yellow fever in Brazil, Suriname and French Guiana, of dengue fever in Côte d’Ivoire and Sri Lanka, and of Chikungunya in Italy. Epidemics of hepatitis A, hepatitis E, Lassa fever, meningococcal disease, the Zika virus infection, polio, and Marburg fever also claimed many lives.

Participate

• Have any epidemics occurred in your country in recent years?
• What do you know about them?
• What impact did they have on the society?

Discuss these questions in your group.

Epidemics occur worldwide. Their magnitude and their consequences depend on the disease in question (causative agent), the people or animals affected (host), and how the disease is spread (mode of transmission). Epidemics can be limited or can spread across continents (pandemics). However, they tend to occur more frequently or to have more severe consequences in populations that have experienced natural disasters, armed conflict, or displacement, that have poor sanitation or lack a secure food and water supply, or whose health system is underdeveloped or has been devastated. Populations that suffer from other health conditions, including malnutrition or low vaccine coverage, are also more vulnerable to epidemics.

Although the most obvious effects of an epidemic are on health, epidemics usually have a much broader impact on society.

First of all, societies affected by an epidemic cease to be productive. The health system is no longer able to deal with other health conditions because healthcare workers are overwhelmed by the epidemic or are themselves ill. If numerous children and teachers are sick, this disrupts education. If community workers and public servants are sick, this disrupts other services. Second, water and food supplies can be contaminated, and many people may consequently lose access to food, safe water and sanitation.

Displaced people and people living in collective accommodation or refugee camps are particularly vulnerable to epidemics. Major epidemics can disrupt family links. Large numbers of ill people and their family members may need psychosocial support.

Finally, epidemics can cause fear and stigma. It is important to involve communities in epidemic control and to understand local cultural practices. Establishing trust and good communication between the community, volunteers and other stakeholders is critical for successful epidemic control.