Bovine papular stomatitis virus (BPSV)

Also known as

Erosive stomatitis of cattle

Description

This worldwide disease is a common and usually mild parapoxvirus infection of calves and young cattle, characterized by a localized papular eruption (circular, solid raised areas) on and around the muzzle and in the mouth.

Lesions on the muzzle may be difficult to see if the area is pigmented. In the mouth the lesions occur on all surfaces except the upper surface of the tongue and are most common inside the lips and near the teeth. Occasional cases occur in which the only lesions are in the esophagus and forestomach (rumen, omasum and reticulum).  In most instances the disease goes unnoticed unless a careful examination of the mouth is made.

Lesions begin as very small papules that become dark red, develop a rough surface, and expand outward from the center (always appearing round or nearly so). Confluence of several lesions may create a large, irregularly-shaped area. As the lesion expands, the periphery becomes reddened and the center depressed, gray-brown, and rough, and eventually covered with dead tissue or a scab. Individual lesions heal quickly, sometimes in 4 to 7 days, but evidence of healed lesions (circular areas of dark pink, usually surrounded by a slightly paler raised zone) may persist for weeks.

The viruses that cause bovine papular stomatitis, pseudocowpox and milker’s nodule are closely related. The development of lesions on the muzzle, margins of the lips, mucous membranes inside the mouth (including the hard palate), and, less frequently, the teats, is similar to that of pseudocowpox.  

Some outbreaks of BPSV infection in dairy herds in Brazil and Japan have been associated with painful skin lesion on the teats of milking cows, causing a decrease in milk production or even an interruption of lactation. Affected animals resist being milked because of severe local pain. Secondary mastitis was reported in some cases.

Papular stomatitis virus may also infect humans and cause lesions indistinguishable from milker’s nodule and very similar to those caused by orf virus (often called sore mouth or scabby mouth).

Diagnosis is based on clinical signs and viral isolation. Handlers may develop lesions on their hands at sites of contact with lesions of cattle.

The parapoxvirus is prevalent in North America and infects cattle from newborns to yearlings (sometimes 2-year-olds). Most of the cases seen in the dairy industry are in young calves that are still on milk. The raised circular or ulcerative lesions on the muzzle, tongue or in the mouth may be painful enough to hinder eating or suckling if they are severe. Most often the majority of these lesions are mild, however. The disease runs its course in a week or two and the lesions go away.  

Severe lesions are generally seen only in debilitated sick calves with other problems. If a calf is immunocompromised for some reason, such as a PI calf (persistently infected with BVD) it may have severe lesions with papular stomatitis. This could also happen if the calf has salmonellosis that has dragged down the immune system.

Papular stomatitis is not a fatal infection by itself, but may be present with other causes of mortality like severe respiratory disease.

The lesions of papular stomatitis can be easily spread from calf to calf with contaminated feeding equipment such as bottles, nipples, or treatment devices that go in the mouth such as esophageal feeding tubes and dose syringes.  

This disease is usually just a nuisance, spread from calf to calf. It’s rare to see it in cattle over a year old, and many affected calves have lesions that are never noticed. If you look closely in their mouths, there may be small lesions on the muzzle or along the tongue, but the calves are not bothered by them. You might only notice lesions if they are severe enough to cause the calf to go off feed. Most infections pass unnoticed, skin lesions are minor, rarely associated with systemic disease, and healing occurs spontaneously.

The disease is not considered of major consequence but high morbidity (many animals affected) may be seen in severe outbreaks. In addition, lesions are similar in appearance to those of vesicular stomatitis, BVDV, and FMDV (foot and mouth disease virus) so it may be necessary to have a correct diagnosis. The primary importance of this disease is that it presents an important differential diagnosis for foot-and-mouth disease.

Like other parapoxviruses such as pseudocowpox and orf (occurring in sheep and goats) it is zoonotic and can be spread to humans. People can get similar lesions on their hands.  

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

Signs

• Reddish raised sometimes ulcerative lesions on the lips, muzzle, and in the mouth and sometimes on the teats
• Temporary lack of appetite
• Weight loss
• Slobbering
• Slight fever (103°F)

Causes

Sub-clinically infected animals are the reservoir of virus. Immunity is of short duration, and cattle can become re-infected. Clinically, the disease is mild, but it needs to be differentiated from foot-and-mouth disease.

The virus is shed in secretions of the respiratory and alimentary tracts (including saliva). Transmission probably occurs by direct contact between infected and susceptible animals. Most clinical cases are observed in spring and early summer. The entire group of calves may be affected. Stress or immunosuppression may lead to disease, and it may recur because immunity is neither solid nor long-lasting.

Adult cattle sometimes get lesions on their teats and udders, especially if a beef cow is being suckled by a calf that has lesions. This may also be a way in which the calf gets it.  The cow may have teat lesions and it is spread to the calf. The lesions may not be very obvious on the teats of the cow, but may be the reason the calf gets lesions in the mouth and muzzle.  Some cows allow more than one calf to nurse, and it can be spread that way.

Transmission occurs fairly easily either through direct contact with skin lesions or through fomites (objects or materials) that may play a role in spreading the disease during outbreaks in milking herds (such as milking machines).

Repeated infection with BPSV has been documented, so is assumed that no immunity occurs and the virus may only cause lesions when another disease causes lowering of the animal’s resistance.

Prevention

If you see a calf with lesions, it’s wise to isolate it from other calves, to prevent spread. Be careful about any comingling or using the same equipment that would be shared, or any possible nose-to-nose contact.  Young animals are very social and orally fixated, nuzzling and chewing on each other, and can spread it.

Treatment

There is no specific treatment, since it is a virus, and healing occurs spontaneously.