Young people in a slum in Kolkata

An international issue

New diseases may emerge in developing countries – but they won’t stay there

Most infectious diseases that pose a global threat – including avian flu, HIV, Ebola, chikungunya and dengue haemorrhagic fever – originated in developing countries.

Living conditions are key factors. In poorer countries people often live in close contact with animals, creating opportunities for animal diseases to spread to humans. The destruction caused by natural disasters can also create the unsanitary conditions in which diseases spread. Cholera, for example, spreads in drinking water contaminated with human waste.

In resource-poor countries many aspects of healthcare may be inadequate – treatment, diagnosis, disease monitoring and disease control. With large numbers of people moving into crowded urban slums with insufficient sanitation, healthcare and clean water, new infections can soon become endemic.

Education and cultural traditions can also play key roles. In the 2014 Ebola epidemic a lack of local knowledge about disease transmission combined with practices that included washing and burying deceased family members helped the disease to spread.

International travel and trade can spread infections globally. HIV/AIDS escaped detection and has grown into one of humankind’s worst ever pandemics.

Poor health hurts countries economically – and poverty has a huge impact on health. This vicious cycle ensures that new diseases will continue to emerge and spread.

Lead image:

Young people in a slum in Kolkata.

Wolfgang Sturneck/Flickr CC BY NC ND


Further reading

About this resource

This resource was first published in ‘Epidemics’ in September 2007 and reviewed and updated in January 2015.

Health, infection and disease, Immunology
Education levels:
16–19, Continuing professional development