Rinderpest

Abstract: Morbilliviruses comprise measles virus, canine distemper virus, rinderpest virus, and several other viruses that cause devastating human and animal diseases accompanied by severe immunosuppression and lymphopenia. Recently, we have shown that human signaling lymphocyte activation molecule (SLAM) is a cellular receptor for measles virus. In this study, we examined whether canine distemper and rinderpest viruses also use canine and bovine SLAMs, respectively, as cellular receptors. The Onderstepoort vaccine strain and two B95a (marmoset B cell line)-isolated strains of canine distemper virus caused extensive cytopathic effects in normally resistant CHO (Chinese hamster ovary) cells after expression of canine SLAM. The Ako vaccine strain of rinderpest virus produced strong cytopathic effects in bovine SLAM-expressing CHO cells. The data on entry with vesicular stomatitis virus pseudotypes bearing measles, canine distemper, or rinderpest virus envelope proteins were consistent with development of cytopathic effects in SLAM-expressing CHO cell clones after infection with the respective viruses, confirming that SLAM acts at the virus entry step (as a cellular receptor). Furthermore, most measles, canine distemper, and rinderpest virus strains examined could any use of the human, canine, and bovine SLAMs to infect cells. Our findings suggest that the use of SLAM as a cellular receptor may be a property common to most, if not all, morbilliviruses and explain the lymphotropism and immunosuppressive nature of morbilliviruses.

Abstract: Rinderpest is a highly contagious ruminant viral disease manifested by a rapid course and greater than 90% mortality Infectious vaccinia virus recombinants were constructed that express either the hemagglutinin or the fusion gene of rinderpest virus All cattle vaccinated with either recombinant or with the combined recombinants produced neutralizing antibodies against rinderpest virus and were protected against the disease when challenged with more than 1000 times the lethal dose of the virus

Abstract: Peste des petits ruminants (PPR) is an acute and highly contagious viral disease of sheep, goats and wild ruminants. The disease is controlled by the use of live-attenuated vaccines that give a lifelong immunity. Currently, several PPR vaccines are available for use in the field that are based on the tissue culture passage attenuation of wild-type PPR isolates. Four such preparations, viz., PPRV/Nigeria/75, PPRV/Sungri/96, PPRV/Arasur/87 and PPRV/Coimbatore/97 are licensed for use. The PPR vaccines comprising of PPRV/Nigeria/75 and PPRV/Sungri/96 are commercially available. While highly efficacious, a drawback to these vaccines is the requirement of a cold chain to preserve vaccine titre in the field. Thermostable live-attenuated vaccines have recently been developed in an attempt to circumvent the problems associated with the maintenance of a cold chain in tropical and subtropical countries. Despite this issue, targeted vaccination programmes for PPR in high-risk populations of sheep and goats constitute an effective control strategy. Lessons learnt from the rinderpest eradication programme suggest that the availability of a DIVA vaccine, to enable the differentiation between infected and vaccinated animals (DIVA), and a companion diagnostic test would greatly aid both the control and the surveillance for PPRV although it is recognised that eradication could be achieved in the absence of these tools. In this chapter, we discuss both the current and potential future vaccine strategies for PPRV and highlight elements of vaccines that are highly desirable in newer vaccine preparations.