and history are normally enough to make a preliminary diagnosis. To definitively diagnose the infection the virus should be identified in the tissues by virus isolation or PCR, or in bulk milk samples by ELISA. Serology may be performed to identify latent carriers, but it is not completely reliable as not all of the infected animals have detectable antibodies. Treatment and control Treatment is symptomatic. Anti-inflammatories reduce fever and provide pain relief. Antibiotics may be necessary if a secondary infection occurs. Vaccination is widely used both to protect cattle clinically in the case of infection and significantly reduce the shedding of the virus. Vaccination provides herd immunity, which lowers the likelihood of an animal coming into contact with an infected animal. Both inactivated and live attenuated vaccines are available. Immunity usually lasts approximately six months to one year. Marker vaccines are also available and recommended. Marker vaccines, also known as DIVA (differentiation of infected from vaccinated animals), have become popular in order to distinguish vaccinated animals from infected animals. A marker vaccine uses either deletion mutants or a virion subunit, such as glycoprotein E. Studies show that vaccinating after an animal has been infected decreases shedding of the disease and reduces reactivation of the latent virus, although not completely. Using a killed gE deleted marker vaccine after infection will reduce viral excretion following reactivation, using a dexamethasone treatment. Animals showing clinical signs should be quarantined to stop the spread of the virus. The use of quarantine in herds with BoHV-1 is not ideal control program, as it is a latent virus and results in lifelong infection. However, new animals coming to a farm, or crossing borders, should be quarantined while tests for the virus are being undergone. Quarantine will also help contain the spread after an outbreak. Eradication Countries such as Austria, Denmark, Finland, Sweden, Italy, Switzerland and Norway have eradicated the disease, while Canada and the United States have control programs in place for it. Eradication of the disease is a time-consuming process and requires diligent testing to be granted a disease free status. The possibilities of eradication rely upon whether the herd is vaccinated and the reactivation potential of the virus. In a small, vaccinated herd BoHV-1 can be eradicated within one or two decades, whereas in a large herds eradication is unlikely. Eradication was accomplished in Switzerland in 5 years using a four-step protocol focusing on preventions