Parasite vaccines - a reality?

Over the last decade, the anti-parasitics market has been the fastest growi ng sector of the overall $18 billion animal health market. While drugs for the treatment of parasites of livestock still dominate this sector and will continue to be developed or re-formulated, because of consumer demands for chemical-free food and of concerns regarding the environment and animal we lfare there is a growing interest in the development of safe and effective vaccines. There is also a call for vaccines in the lucrative $3 billion-plu s companion animal market. These demands for vaccines will add a greater im petus to an area that has seen tremendous success in the last 15 years. A n umber of anti-parasite vaccines have been developed, e.g. the recombinant 4 5w and EG95 oncosphere proteins against Taenia ovis and Echinococcus granul osis, respectively, and the Bm86 vaccine against Boophilus microplus. In ad dition, the cathepsin L vaccines against the liver fluke, Fasciola hepatica , and the H11 vaccine against Haemonchus contortus are progressing well. Th ere are also many additional vaccine candidates for H. contortus and for ot her nematodes such as Ostertagia and Trichostrongylus spp. that may ultimat ely lead to broad-spectrum gastrointestinal worm vaccines. Live or attenuat ed-live vaccines are available for the control of avian coccidiosis, toxpla smosis in sheep and anaplasmosis in cattle, although molecular vaccines aga inst protozoans are still proving elusive. The wealth of information in gen omics, proteomics and immunology that has been forthcoming together will ne w methods of vaccine production and delivery should see many new vaccines r each the marketplace in the near future. (C) 2001 Elsevier Science B.V. All rights reserved.