Viral haemorrhagic fevers

Abstract

Abstract Viral haemorrhagic fevers are viral infections that can cause shock, haemorrhage and multi-organ dysfunction. Their geographical distribution is limited by the ecology of their vectors, and many of them exist in tropical zones. The most common viral haemorrhagic fevers are not transmissible from person to person, and no viral haemorrhagic fevers are a threat to casual contacts. However, four viruses for which prevention and treatment are unreliable or not available (Crimean-Congo, Ebola, Lassa and Marburg) can be transmitted to health-care or laboratory workers. Household and health-care-related transmission is mainly limited to carers of severely ill patients, particularly patients who are highly dependent or suffering severe haemorrhage. Specialist laboratories and clinical referral centres advise on the risk assessment of suspected cases and support management of proven cases. Patients with fever after visiting viral haemorrhagic fever-endemic areas are often infected with falciparum malaria, which can cause life-threatening disease if it is not recognized and treated. Malaria should always be excluded before considering a diagnosis of viral haemorrhagic fever. If malaria or another treatable disease is not evident, or there is a definite history of direct viral haemorrhagic fever exposure, advice should be sought from an expert unit, to arrange early and safe case-management.