Burden and cost of imported infections admitted to infectious diseases units in England and Wales in 1998 and 1999

Background. International travel from the UK has been rising, and the number of imported infections has increased. This study aimed to describe the number, nature, origin, clinical burden and cost of imported infections treated in infectious disease units (IDU) in England and Wales. Method. Information about all admissions in 1998 and 1999 with illnesses considered to have been acquired during their most recent travel abroad was collected retrospectively by IDUs using a pre-piloted questionnaire. Results and analysis. Four of the 23 IDUs in England and Wales were able to complete the questionnaires. They reported a total of 421 travel related admissions during the 2-year period. Three hundred and ninety-two of these cases were attributed to infectious causes, and of these a discharge diagnosis was made for 340 cases. The total number of bed days used to treat cases of imported infection was 2918. The most common diagnosis was malaria. The odds ratio that cases of imported infection were malaria was highest following visits to Africa. The average cost per bed day on the IDUs was around £100, and on this basis, the total cost of treating imported infections on the four IDUs in 2 years was around £289,000. The relative risk of acquiring an imported infection requiring treatment on an IDU was greatest for travellers to Africa. Conclusions. From this study, the estimate of the total annual cost of IDU treatment for imported infections in England and Wales is in excess of £800,000. Many cases may be preventable with prophylactic medication and vaccination and travel advice on risk reduction. Further information about imported infections would be useful to inform travel medicine services, other clinicians and travellers about the health risks associated with travel to specific areas, and help to target and assess the cost effectiveness of preventative measures.