Lyophilisation of Theileria parva sporozoite stabilates used for immunisation of cattle against East Coast fever would greatly improve vaccine storage and delivery. We report three attempts to lyophilise and resuscitate the sporozoites of T parva. Sporozoites survived lyophilisation and were effective for immunisation. Lyophilised stabilate survived for 2 weeks at 5degreesC and for 12 weeks at -20degreesC. Although the viability of the stabilates was severely reduced during lyophilisation, this work suggests that this method has potential and should be considered for other Apicomplexan parasites such as Babesia sp. or Plasmodium sp. (C) 2003 Elsevier Ltd. All rights reserved.