Quinton L Fivelman1
, Geoffrey A Butcher2
, Ipemida S Adagu1
, David C Warhurst1
and Geoffrey Pasvol3 
1
Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London, WC1E 7HT, UK
2
Department of Biology, Sir Alexander Fleming Building, Impeial College, Imperial College Road, London, SW7 2AZ, UK
3
Department of Infection and Tropical Medicine, Faculty of Medicine, Imperial College, Lister Unit, Northwick Park Hospital, Harrow, Middlesex, HA1 3UJ, UK