Zoetis.co.uk uses cookies to improve your experience when browsing our website. By continuing to use this site, you are agreeing to their use. To find out more, view our cookie policy.

United Kingdom
Cow and calf

Infectious Bovine Rhinotracheitis

IBR is a contagious respiratory disease of cattle caused by bovine herpesvirus type 1 (BoHV-1), commonly affecting the respiratory tract and the reproductive system. Many European countries have already obtained a free status and in others, eradication programs are running, however in the UK to date control of the disease has been at a local level. All ages of animals are potentially at risk. Although ‘classic’ IBR tends to occur in store cattle, IBR has been shown to be involved in the cases of pneumonia in younger calves on some farms. Anecdotally, IBR appears to be on the rise in dairy herds, with freshly calved heifers being most at risk. With no national eradication effort on the horizon, it is down to individual farmers and vets to come up with control programmes to limit disease at a farm level. All animals that are infected become carriers.

True prevalence is not known, but in 1998 a survey of bulk milk antibodies from 341 dairy herds in England and Wales showed 69% sero-positive¹ (Paton et al, 1998) and in 2008, O’Grady et al found that 73% of Irish beef herds had serological evidence of exposure to BoHV-1.²

Expand All
  • Bovine Herpes Virus-1 (BoHV1) belongs to the Herpes family, in common with the human cold sore virus. BoHV1 is a highly contagious virus and is found in nasal/eye discharge, vaginal secretions and semen. It can spread both via direct contact between animals and also by indirect routes such as via contaminated clothing or equipment. After infection, the virus becomes ‘latent’ in 100% of cases – the virus retreats to the nervous system and lies dormant, but if the animal is stressed the virus can ‘recrudesce’, becoming active and infectious again. This means that any animal that has had IBR in the past can be a source of infection to other animals, even if there are no outward signs of disease. Therefore, any bought in animal of unknown status should be tested for IBR (amongst other diseases) and isolated until the result is known. This is especially true if your herd is free of IBR.

  • IBR can cause a high temperature, depression, loss of appetite and general dullness. It mainly affects two body systems

    • the respiratory tract (cough, nasal discharge, upper respiratory tract infection.)
    • the reproductive system (abortion, birth defects, pustules on the vagina / penis).

    In adult dairy cattle, one of the early signs of BoHV1 infection is a reduction in milk yield, it is also believed that IBR in freshly calved cows may reduce fertility. In dairy cows, acute respiratory disease may not necessarily be a feature of the infection.

     

    Clinical signs can range from extremely mild to very severe (including death), depending on the immune status and the level of viral challenge.

  • A suspicion of IBR may be raised based on clinical signs and the nature of an outbreak, but laboratory testing is required for a definitive diagnosis. Laboratory tests usually focus on identification of the virus (eg in discharge, a post mortem or an aborted foetus), or identification of an immune response to the virus, via blood tests. Because the virus becomes permanently established in 100% of cases, any animal which tests positive on blood results (and has not been vaccinated) poses a risk to other animals.

  • During an outbreak, in order to reduce the impact of secondary bacterial pathogens, treatment will be symptomatic, using antibiotics and possibly non–steroidal anti-inflammatories (NSAIDs). Corticosteriods are contra-indicated as they will increase the shedding of virus by affected animals. IBR outbreaks are unique in that intranasal vaccination in the face of an outbreak will reduce the severity of the outbreak particularly if implemented early in the time course of the disease. This is because the spread of IBR within a herd in the initial stages of an outbreak is slower than the spread of other respiratory viruses such as RSV and PI3.

  • Clinical signs of disease (including respiratory disease and abortion) may be controlled by vaccination. However, to reduce circulating virus at a herd level a more concerted effort will be required. Programmes are often two-fold, involving a biosecurity plan to prevent new infection being brought into the herd, and a vaccination programme to reduce circulation of virus within the herd. There are several different vaccines available in the UK, all have a six month duration of immunity. Some vaccines cover several different viruses while others are designed specifically to cover IBR. In recent years, marker vaccines have become available; these allow blood testing to distinguish between a vaccinated animal and an infected animal. Originally, marker vaccines were thought to be the preserve of breeders, but more and more commercial herds have begun to use marker vaccines, as they make it easier to determine the success of any control programme.  Live vaccines have been shown to be better at protecting against clinical respiratory disease and in reducing viral shedding of acutely infected animals³, while inactivated vaccines have been shown to be more effective at reducing shedding in latently affected carriers⁴. The type of vaccine used, and the route by which it should be given will depend on the type of herd and the level of risk of IBR. For example, a truly robust vaccination programme in an infected suckler or dairy herd may require both of these vaccines to be used. In bought in store cattle, speed of onset will be of the highest priority. In a naive herd, vaccination may still be an important part of control, if biosecurity alone is deemed not be enough to keep infection out.

  • Q: Why are there so many IBR vaccines available – aren’t they all the same?

    The many IBR vaccines on the market have evolved over time, but each one has different attributes.  We now have live and inactivated, marker and non-marker, mono- and multi-valent vaccines.  This means that any vaccination programme can be tailored to the farm and the situation, rather than trying to employ a ‘one size fits all’ policy.  While this may be the most straightforward way to plan a vaccination policy, its not necessarily the most effective way to use vaccines – you need to get the maximum benefit out of the money you spend on control.

    Q: How do I find out my IBR status?

    In dairy herds a bulk tank test to look for antibodies is probably the cheapest and easiest way to determine your herd infection status.  In beef suckler herds, screening blood tests can be used to look for exposure to virus.  Where stores or calves are bought in on a regular basis, there may be little value in determining current IBR status, as each group of animals bought in may have a different disease profile, especially if they are purchased from different sources.

    Q: I am a breeder who sends bulls to stud or exports animals, does this mean I can’t use IBR vaccines?

    We would always advise consultation with your vet in devising a vaccination regime, however, we can give some general advice.  Some people who send bulls to stud or export animals chose to vaccinate the rest of the animals in the herd to provide something of a barrier should biosecurity measures fail to keep infection out completely.  In this case, it is necessary to use a marker vaccine and an inactivated vaccine would be the best choice.  This is because live IBR vaccines can behave like the wild-type virus and become latent.  In this instance, they do not cause any harm, but they may be shed at times of stress in amounts sufficient to ‘infect’ the unvaccinated animal.  Again, this will not cause disease in the animal but may cause it to test positive for a marker vaccine on blood tests.  All studs require bulls to be completely free of antibodies to BoHV-1, even if tests show that a marker vaccine has been used, and the same is true of some countries in Europe.  It is therefore advisable to check with the country you plan to export to, before putting a vaccination protocol in place.

  • 1 Paton et al. Veterinary Record (1998) 142, 385-391
    2 O’Grady et al. Irish Veterinary Journal Volume 61 Number 12 809-815, 2008
    3 Bosche et al. An attenuated bovine Herpesvirus 1 marker vaccine induces a better protection than two inactivate marker vaccines. Veterinary Microbiology 52 (1996) 223-234
    4 Bosche et al. Inactivate bovine Herpesvirus 1 marker vaccines are more efficacious in reducing virus excretion than a live marker vaccine. 1997. Vaccine, Col 15, No. 14, 1512 - 1517