Fruit bats

Humans and pathogens

The way humans live has had a huge impact on the spread of disease

An animal species that carries a pathogen transmitted to people is known as a reservoir. An organism that transfers a pathogen is known as a vector.

For example, the fruit bat is thought to be a reservoir for Ebola. The mosquito is a vector of malaria, yellow fever, dengue fever and chikungunya virus.

Living in groups brings potential hosts close together. For example, living with domesticated animals increases the risk of pathogens jumping species. The migration of people and animals means that diseases spread to new areas, and migrants can be exposed to new risks.

Sanitation is a major factor in the spread of disease. Poor sanitation can create environments around humans in which pathogens can multiply and that vector species, such as insects or rodents, find attractive.

Lead image:

Fruit bats.

shellac/Flickr CC BY

Further reading

About this resource

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

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