Brucellosis Vaccination: Still a Good Idea?

Imagine 10% of the nation’s beef and dairy cattle herd infected with a contagious disease causing pregnancy loss and reproductive failure. What’s more, that same contagious disease makes people sick, sometimes with long-term repercussions. That was the situation in the mid-1930’s with brucellosis. This bacterial reproductive disease had already been implicated for decades as a significant animal and public health problem.

USDA Brucellosis Eradication Program

In 1934 the USDA, in conjunction with state officials, embarked on a brucellosis eradication program, remnants of which continue today. Early eradication efforts consisted of blood testing and slaughtering infected animals. While that helped rid herds of a source of infection, it did nothing to prevent those infected cows from spreading the bacteria before they were detected.

That all changed in the early 1940s with the development of a brucellosis vaccine (the “Bangs vaccine”) for cattle. Named the “Strain 19” vaccine, it quickly proved to be effective. Even if it did not prevent 100% of infections, it greatly reduced abortions and therefore disease transmission. In the mid-1990s, Strain 19 was replaced as the approved vaccine by “RB51,” which offers similar protection but fewer problems with blood test interference.

It took time, but the US brucellosis eradication program can now be considered a success. Cattle brucellosis has been eradicated across the country, except for areas surrounding Yellowstone Park, where wildlife remains as a reservoir. As a result, many states have dropped requirements for brucellosis vaccination of heifers for their resident cattle and for animals entering from other states.

Brucellosis Vaccination Today

If most brucellosis vaccination requirements are no longer in effect, why should cattle producers continue to make the effort?

• Bangs vaccination time is a good time for other heifer management practices as well. Rules restrict brucellosis vaccination to heifers between the ages of 4 and 12 months of age. During this time, heifers identified as replacements can also be given their first dose of pre- breeding reproductive vaccine, palpated for reproductive score, pelvic measured, retagged, and have their udders examined. In addition, since brucellosis vaccine must be administered by an accredited veterinarian, it gives the operation a built-in chance to utilize veterinary expertise to help select and prepare replacement heifers.
• Bangs vaccination automatically gives heifers a USDA official ID. Vaccinated heifers receive an official tattoo designating the year of vaccination as well as a metal (or possibly RFID) official identification tag. Even though brucellosis vaccination is not required to cross most state lines anymore, official identification is.
• Bangs vaccination makes state officials’ jobs easier. Brucellosis-vaccinated heifers have their official ID’s recorded and sent to the state veterinarian’s office for storage. Those records and ID’s can become invaluable in investigations of disease outbreaks such as tuberculosis. Having identification such as the Bang’s tag number might mean the difference between an operation being declared “all clear” and having to test their animals when it comes to these disease tracebacks.
• Bangs vaccination still holds value for many heifer purchasers. At the very least, it indicates that the heifers have been run though a chute and have at least had a chance to be examined and managed more closely than those not vaccinated against Brucellosis.
• Brucellosis hasn’t been eradicated from the face of the earth yet. Yes, the chance of a dairy or beef cow encountering brucellosis in our South Dakota herds is so low as to generally be disregarded. But as long as a source of the disease exists in the greater Yellowstone area – and other countries – protection is not a bad idea. If the day ever comes when brucellosis vaccination is a rarity, we could have a cattle population once again quite susceptible to that important disease.

The Bottom Line

For beef and dairy producers, the best source of information on how brucellosis vaccination fits into an operation is their local veterinarian. In South Dakota, the Animal Industry Board has a great deal of useful information on brucellosis.