THE ERADICATION OF BOVINE TUBERCULOSIS

IN WISCONSIN by Fred J. Born, DVM

Copyright © 2015All rights reserved

With Robert Koch’s discovery of the tubercle bacillus in 1882, advanced the understanding of tuberculosis. In 1892, Leonard Pearson, who recently had been studying bacteriology under Koch, introduced tuberculin testing in the United States. Arresting Contagion, Olmstead and Rhode, 2015, p. 222.

As early as 1883, some Wisconsin veterinarians were aware of the challenges that this new dairy industry would bring. They realized the urgent need of a state veterinary medical association that could deal with the complex laws and recommend regulations to control cattle diseases within the state and work with the federal government.

 

In 1888, the Eastern States reported nearly one out of eight persons died from tuberculosis, or consumption, and TB dairy cows were a major source of that infection. 

Beginning in 1892, veterinarians conducted tuberculin tests on herds of cattle and state authorities ordered the slaughter of infected animals.

Waukesha County was the first county in the United States to have cattle tested for tuberculosis. These TB testing procedures helped remove tuberculosis from the list of the most common causes of human disease by 1939.

 

Beginning in 1893, the BAI produced and distributed freely to state livestock sanitary officials diagnostic materials including tuberculin for testing bovines for BTB and mullein (discovered in 1890) for testing equines for glanders. USDA, Yearbook of Agriculture, 1906, pp. 347-54

In the years building up to 1895, the veterinary medical profession was aware of bovine tuberculosis and its the transmission to humans. The development of the tuberculin test in cattle gave the veterinarian the tool to detect the infected cattle. During this time, two very important zoonotic diseases would dominate the attention of the veterinary medical profession, Bovine tuberculosis and Bang’s disease (Brucellosis), also known as “Undulant” fever in humans.

In the next half century, many WVMA members stepped up and became major players in this fight to eradicate both of these diseases on the state and national level.

It was in 1895, the public was told through newspaper articles about TB in cattle. In the same year, bacteriologist H. L. Russell of the University of Wisconsin returned from training in Koch’s laboratory with tuberculin. When he tested the university’s herd, 26 out of 30 animals reacted. Disbelievers were won over when post-mortem examinations confirmed the results. Arresting Contagion, Olmstead and Rhode, 2015, p. 222.

The earliest form of the tuberculin test involved injecting the substance beneath the animal’s skin (the subcutaneous test) and checking for signs of a fever. This procedure required many hours of a veterinarian’s time and a large quantity of expensive tuberculin. To obtain an accurate result, theveterinarian had to take the animal’s temperature, typically three to four times at two-hour intervals, before the injection to establish a baseline reading. Then, beginning about six hours after the injection, the veterinarian again took temperature readings every two to three hours, continuing the process for up to twenty-four hours. Surviving test charts show that to test a herd the veterinarian had to be on site for about thirty-six hours, inspecting each animal from ten to fifteen times. As an example, a veterinarian began his baseline temperature tests at 10:00 am on 16 January 1914, injected the tuberculin at 8:00 pm, and began the last round to testing at 2:00 pm the following day.

A far cheaper approach, suited to mass testing, became the standard practice in 1920. Employing the new (intradermic) process, the tester injected a few drops of tuberculin into the animal – usually in a flap in the tail – and then returned to examine the animal visually two to three days later. If the site of the intradermic injection showed significant signs of swelling, the animal was labeled a reactor. This procedure represented an important labor-saving technological advance. A veterinarian could test three herds in a day – a job that had previous taken a week. Testing was not an exact science. Under either procedure, detecting a “reaction” was a judgment call. Both false positives and false negatives occurred, with some of the false negatives due to recent exposure to tuberculin that “produces a tolerance . . . lasting for about six weeks.” Thus, the standard testing protocols required that the subject animal had not been tested in the previous sixty to ninety days. Arresting Contagion Olmstead – Rhode -Harvard University Press, 2015, p. 222.

The Passing of the Hunchback

This hunchback – once fairly common – is rapidly passing from America. Today we see very few of these unfortunate cripples below the age of twenty. The condition, a permanent malformation of the bones, was usually due to tuberculosis, which was transmitted to children through the milk of affected cows. But a campaign of systematic testing, inaugurated in 1920, has practically eliminated tuberculosis from the country’s dairy herds – and this malformation from the bones of its children.

This campaign was pioneered by veterinarians, is still administered by them. The passing of the hunchback is, therefore, one of the truly great contributions of the veterinary profession to human welfare.

This poster reminds many of us who lived in the 1940s and early 1950s, remembering the “hunchback” individuals. There were numerous TB sanitariums throughout the state, you may have had a relative or two receiving treatment at one of these facilities.

When the University of Wisconsin Dept. of Veterinary Science was established in 1911, the four main diseases were Bovine TB, Brucellosis, Johne’s Disease and Hog Cholera.

There was a short course at University of Wisconsin in January, 1923 for veterinarians to learn how to do the agglutination test for “contagious abortion” – brucellosis.

Early TB testing of cattle was started in Wisconsin before it was used nationally. The testing procedure was changed, and how it was changed makes this an amazing story. Dr. Arlye McDermid (1954 WVMA president) told what happened in the basement of his veterinary hospital would never happen today. The unorthodox manner in which the federal and state veterinarians conducted this meeting was told in Dr. McDermid’s interview. The complete story was not fully recorded in his transcription in the WVMA Oral Histories of the past-presidents book. Dr. McDermid was asked to hold a meeting at his hospital in the evening, a room that could hold 50-55 people. Veterinarians from the area were invited that had experience in TB testing a large number of cattle in their practices.

After all of the invited 50 veterinarians arrived and were seated, the head federal investigator walked over to the only door in the room and locked the door. Turning to the group and said no one will leave this room till we resolve this issue of false positives to our TB testing procedure. There was no publicity, nor minutes taken. The problem that most of the veterinarians encountered was chickens with avian TB were loose to feed and defecate in the cattle managers. The result was, with still no publicity, a change in the tuberculin with more specificity and sensibility. It was believed that the federal government, which furnished the tuberculin at that time, had this thing on the back burner. This just stimulated them to get the bovine tuberculin to the veterinary medical practitioners, nationwide.

A complete TB testing case

U.S. Government issued TB syringe with a flashlight attached

TB syringe with a finger switch for the flashlight attached

Standard TB syringe in a leather case

TB testing paint stick to identify cattle that had been injected

Official TB gauge

The “T” branding iron was used to identify TB reactors

“The conquest of tuberculosis was perhaps one of the greatest medical accomplishments of all time. It stands as a monument to all those who gave so much to see it vanquished, and it provides hope for future control of other diseases.”Reference: A paper given at the annual AVMHS Meeting in Salt Lake City, UT, July 1982 by Kate Faler