Re: Risk factors for mortality from imported falciparum malaria in the United Kingdom over 20 years: an observational study
Checkley and colleagues report an important study of the factors associated with malaria mortality in the UK using statutory notification data.  The principal finding that mortality increases with increasing age and is higher in malaria-naïve holidaymakers is striking.
The peak of mortality in December is also interesting. Analogies are drawn with cardiovascular mortality (which peaks over the festive period). Since malaria infection requires travel to an endemic region “winter sun” holidays are also proposed. There was a higher risk of mortality associated with travel to the Gambia, a popular package holiday destination. In addition, the authors suggest that misdiagnosis of influenza-like illness may be a factor: we have recently confirmed that clinical features alone poorly distinguish malaria from influenza in controlled experimental infections. 
Importantly the majority (94.3%) of individuals identified by Checkley and colleagues had not received effective chemoprophylaxis, although several cautions surround the completeness of the chemoprophylaxis data. 
Nevertheless, this study identifies a high-risk group for which an effective intervention currently exists (chemoprophylaxis), and intervention strategies to target these individuals are urgently needed. Most package holiday companies require holidaymakers to hold travel insurance, or at least declare they will obtain it. A similar requirement with regards to malaria advice/chemoprophylaxis for travellers to malaria-endemic regions should be considered.
1. Checkley, A. M.; Smith, A.; Smith, V.; Blaze, M.; Bradley, D.; Chiodini, P. L.; Whitty, C. J., Risk factors for mortality from imported falciparum malaria in the United Kingdom over 20 years: an observational study. BMJ 2012, 344, e2116.
2. Lillie, P. J.; Duncan, C. J. A.; Sheehy, S. H.; Meyer, J.; O'Hara, G. A.; Gilbert, S. C.; Hill, A. V. S., Distinguishing malaria and influenza: early clinical features in controlled human experimental infection studies. Travel Medicine and Infectious Disease 2012, (in press).
Competing interests: No competing interests