Examples of viral haemorrhagic fevers include Lassa fever, Crimean-Congo haemorrhagic fever, Marburg and Ebola. Because the viruses depend on their animal hosts for survival, they are usually restricted to the geographical area inhabited by those animals. The viruses are endemic in areas of Africa, South America and Asia. Humans are not the natural host for these viruses, which normally live in wild animals. Rodents such as the multi-mammate rat, cotton rat and house mouse are the main reservoirs, while bats have been implicated for the filoviruses (Marburg and Ebola).

The HPA provides diagnostic facilities at two reference laboratories