Improved formulations for existing CBPP vaccines--recommendations for change.

Contagious bovine pleuropneumonia (CBPP) is an economically important transboundary disease, widely present in sub-saharan Africa. Social, cultural and economic factors mean that effective vaccination is the only viable control policy at present. Unfortunately, contemporary live attenuated vaccines are reportedly of limited efficacy and have been unable to control recent outbreaks. Efforts to develop newer vaccine technologies are currently underway, although with little success to date. This review examines the prospects of success for such approaches, and argues that alternative strategies, based upon simple and inexpensive changes to current vaccines and protocols are likely to prove far more effective in the foreseeable future. Such changes include the use of HEPES-buffer systems and the inclusion of pH indicators in vaccine media, together with restrictions in the use of 1M MgSO4 as a vaccine diluent. These changes can increase vaccine yields 10-fold and stability several 100-fold, increase the ease of production, provide a significant level of end user-enforceable quality control, and ultimately produce a vaccine which should prove effective in the field immediately.