Background and history

This is a viral disease that causes nervous symptoms, reproductive failure and opacity or bluing of the cornea. It is seen in Mexico and it has never been diagnosed in any other countries and is unlikely to spread to them.

Worst affected are piglets under two weeks of age. Up to 90 percent die. Up to 65 percent of litters may be affected. The disease disappears slowly and spontaneously after several weeks.

There are several diseases with similar clinical signs, including: in Japan, a paramyxovirus (the Sendai virus); aujeszky's disease (AD); porcine reproductive and respiratory syndrome (PRRS); ontario encephalitis (vomiting and wasting disease); brucellosis. However, none of them have all the clinical signs of BE.

Clinical signs

• Inappetence.
• Corneal opacity – conjunctivitis.
• Nervous signs – fits and convulsions.
• Dog sitting position.
• Shivering.
• Difficulty walking.
• Rough coats.
• Fever.
• Sneezing and coughing.
• Increased returns.
• Increased weaning to mating intervals.
• Stillbirths.
• Mummified piglets.
• High mortality in piglets.
• Swollen testicles (usually one-sided).
  • Followed by shrinking and loss of fertility.

• Loss of libido.

Diagnosis

• Clinical symptoms.
• Haemagglutination inhibition (HI) tests.
• Serological tests.
• Virus isolation.

Causes

• It is thought to be caused by a paramyxovirus known as La Piedad-Michoacán Mexico virus (LPMV).
• Carrier pigs.
• Nasal spread.
• Mechanical spread.

Prevention

• Biosecurity – This should reduce the chances of your herd being infected.
• On-farm eradication – Once a herd has been infected and clinical signs have disappeared the virus may disappear. To help this do not introduce replacement stock into the herd for 1–2 months.
• Vaccination – There is currently no vaccination. Watch the market.

Treatment

There is no effective treatment.