Viral haemorrhagic fevers imported into non-endemic countries: risk assessment and management.

BACKGROUND: Viral haemorrhagic fevers (VHFs) are severe infections capable of causing haemorrhagic disease and fatal multi-organ failure. Crimean-Congo, Marburg, Ebola and Lassa viruses cause both sporadic cases and large epidemics over wide endemic areas. SOURCES OF DATA: Original articles and reviews identified by PubMed search and personal reading; European and United States national guidance and legislation. World Health Organization information, documents and reports. VHFs cause significant morbidity and mortality in their endemic areas; they can cause healthcare-related infections, and their broad diversity and range are increasingly recognized. AREAS OF CONTROVERSY: There is uncertainty about the risks presented by VHFs in non-endemic countries, particularly in healthcare environments. Consensus on the best modes of care and infection control are only slowly emerging. GROWING POINTS: With increasing commerce in rural and low-income areas, VHF outbreaks increasingly expand, causing social and economic damage. AREAS TIMELY FOR DEVELOPING RESEARCH: New ecologies, viral strains and clinical syndromes are being discovered. There is a great need for rapid diagnostic tests and effective antiviral treatments. Vaccine development programmes are challenged by multiple viral strains and the need for trials in rural communities.