Bovine papular stomatitis

E MUNZ AND K DUMBELL

GENERAL INTRODUCTION: POXVIRIDAE

Introduction

Bovine papular stomatitis is a common and usually mild parapoxvirus infection of calves and younger cattle, characterized by a localized papular exanthema on and around the muzzle.

The disease occurs worldwide and sometimes has a high prevalence.³ It may be of economic importance on calf-rearing farms or fattening stations.⁵ The causative virus was isolated for the first time in Nigeria and Kenya.^{8, 9} In South Africa bovine papular stomatitis has been known for many years as ‘erosive stomatitis of cattle’.⁴

Papular stomatitis virus may infect humans and cause lesions that are clinically indistinguishable from milker’s nodule and very similar to those caused by orf virus.^{2, 6}

Aetiology

The parapoxvirus of bovine papular stomatitis can be propagated in a variety of bovine, ovine and human cell cultures. Embryonated hens’ eggs and laboratory animals are not susceptible.

The viruses of bovine papular stomatitis, pseudocowpox and milker’s nodule are closely related.⁶

Epidemiology

The virus is shed in secretions of the respiratory and alimentary tracts (including saliva) but the routes of infection are not yet completely understood. Transmission probably occurs by direct contact between infected and susceptible animals. Most clinical cases are observed in spring and early summer. Morbidity rates may reach 100 per cent.

Stress or immunosuppression may precipitate disease in inapparently infected animals.¹⁰ Bovine papular stomatitis, therefore, is considered to belong to the so-called crowding syndrome complex. Recurrent disease is possible as immunity is neither solid nor long-lasting.

Clinical signs and pathology

The incubation period varies from two to four days. Erythema is followed by a variable number of proliferative or erosive lesions, 5 to 15 mm in diameter, on the muzzle, lips, and inside the nostrils and mouth (Figure 113.1). Rarely, lesions may be found in the oesophagus and rumen. The lesions regress after one or two weeks, but evidence of the healed lesions may be present as brownish spots for several weeks. There is usually no systemic illness.

Figure 113.1  Bovine papular stomatitis: erosions in the mouth

Diagnosis and differential diagnosis

A tentative diagnosis can be made clinically, and the virus can be rapidly identified in negatively stained preparations of lesions examined by electron microscopy.⁷ However, virus cultivation takes much longer. Serological tests to detect antigen or antibodies are of no great practical value.

Microscopically, basophilic and eosinophilic intracytoplasmic inclusions may be observed in epithelial cells in and adjacent to lesions. All forms of stomatitis in cattle, including foot-andmouth disease, bovine virus diarrhoea/mucosal disease and rinderpest, must be taken into consideration in the differential diagnosis.

Control

There is as yet no specific treatment for bovine papular stomatitis. A heterologous live vaccine (based on attenuated orf virus) has been introduced on an experimental basis, but its efficacy is still under investigation.⁵

References

1. bachmann, p.a., gedek, b., mahnel, h., mayr, a. & schels, h., 1984. Poxviridae. In: mayr, a., (ed.). Rolle/Mayr: Medizinische Mikrobiologie, lnfektions- und Seuchenlehre. 5th edn. Stuttgart: Enke-Verlag.
2. bowman, k.f., barbery, r.t., swango, l.j. & schnurrenberger, p.r., 1981. Cutaneous form of bovine papular stomatitis in man. Journal of the American Medical Association, 246, 1813–1818.
3. dunant, p.h., perroud, p. & steck, f., 1975. Stomatite papuleuse des bovins. Schweizer Archiv fu¨r Tierheilkunde, 117, 503–515.
4. mason, j.h. & neitz, w.o., 1940. Erosive stomatitis of cattle. Onderstepoort Journal of Veterinary Science and Animal Industry, 15, 159–173.
5. mayr, a., eissner, g. & mayr-bibrack, b., 1984. Handbuch der Schutzimpfungen in der Tiermedizin. Berlin: Verlag Paul Parey.
6. nagington, j., lauder, i.m. & smith, j.s., 1967. Bovine papular stomatitis, pseudocowpox and milker’s nodules. The Veterinary Record, 79, 306–313.
7. nagington, j., plowright, w. & horne, r.w., 1962. The morphology of bovine papular stomatitis virus. Virology, 17, 361–364.
8. plowright, w. & ferris, r.d., 1959. Papular stomatitis of cattle in Kenya and Nigeria. The Veterinary Record, 71, 718–723.
9. plowright, w. & ferris, r.d., 1959. Papular stomatitis of cattle. II. Reproduction of the disease with culture-passaged virus. The Veterinary Record, 71, 828–832.
10. snider, t.g. iii., mcconnell, s. & pierce, k.r., 1982. Increased incidence of bovine papular stomatitis in neonatal calves. Archives of Virology, 71, 251–258.