Disease Alert: Equine Herpesvirus (2024)

FAQs

What is the prognosis for equine herpesvirus? ›

In most cases, horses exposed to EHV-1 will develop a fever and possibly nasal discharge and then go on to recover. However, the neurologic EHM strain has a high mortality rate of 30-50%. Recovery time can vary from several days to more than a year.

Respiratory shedding of the virus generally occurs for 7-10 days, but may persist longer in clinically infected horses. Similar to herpes viruses in other species, the latent form of EHV-1 can reactivate at a later date, but generally with a low viral load posing a low risk of infecting other horses.

The pathogenic mechanisms of EHV-1 and EHV-4 differ: EHV-4 infection is restricted to the respiratory tract epithelium and associated lymph nodes, whereas EHV-1 strains develop lymphocyte-associated viremia and have a predilection for vascular endothelium, especially within the nasal mucosa, lungs, placenta, adrenal, ...

Equine herpesvirus-1(EHV-1) is a monitored reportable disease for which no regulatory action is taken.

Though genital herpes is not curable, it can be managed.

The symptoms of genital herpes often go away and come back as recurring outbreaks. For most people, the first outbreak is the worst, and can last from two to three weeks. Future flare-ups are often less severe and do not last as long. Still, some people shed the virus regularly.

Is there a treatment for EHM? The standard form of care for EHM is primarily supportive. Treatments may include intravenous fluids or anti-inflammatory drugs. Antibiotics may be used to treat a secondary bacterial infection if one develops; however, antibiotics have no effect on the equine herpesvirus itself.

Most horses recover within two weeks however in some horses a post-viral cough can persist for a much longer time and in some individuals it can take up to six months to regain full health.

EHV is characterized by respiratory infections, paralysis, abortions, inflammation of the spinal cord and occasionally death in young horses. EHV is highly contagious, spreading through aerosolized secretions, contact with infected horses, and contaminated feed and water utensils.

Vaccination for influenza and Equine Herpes Virus (EHV) is recommended in most cases, especially in performance horses and horses exposed to a transient or young equine population.

What is equine herpesvirus type 5? ›

Equine herpesvirus-5 (EHV-5) is commonly found in healthy asymptomatic horses worldwide. Although a cause-and-effect relationship has not been thoroughly determined, this virus has been associated with several disease conditions including equine multinodular pulmonary fibrosis (EMPF) and 1 case of interface dermatitis.

You can readily kill EHV-1 with many common disinfectants including diluted bleach, quaternary ammonium compounds, accelerated peroxide and peroxygen compounds, and iodophors.

Length of quarantine: 21 days after the LAST clinical sign which is usually temperature.

Incubation period: 2-8 days. Once a fever occurs, neurologic signs may develop within the next week. Shedding: Shedding in horses with EHM may occur for as long as 28 days. The virus does not survive outside of the host for very long in the environment.

Horses with signs of EHM also likely still shed the virus via the respiratory tract. While it is still unclear how long the duration of nasal shedding of EHV-1 can be expected to last [11], some can shed up to 4–8 weeks after the onset of neurological deficits [12].

Prognosis for horses with IMMK

Some horses maintain acceptable vision, while others, especially those with endothelial IMMK, may lose significant vision.

Most affected horses die within several days. All horses are at risk although young adults (six months to two years) are particularly vulnerable.

The outlook for horses with pleuropneumonia has greatly improved over the past 20 years due to early recognition, advancements in diagnostic testing, and aggressive therapy. The survival rate is reported to be as high as 90% by some investigators with a 60% chance to return to athletic performance.

The case-fatality rate in outbreaks of EVA is very low; mortality is usually only seen in very young foals, particularly those congenitally infected with the virus (Timoney & McCollum, 1993; Vaala et al., 1992), and very rarely in otherwise healthy adult horses.