The Most Common Infection Spread From Animals to Humans
BY PAT HILL
Brucellosis is a disease most often associated with cattle, bison, or elk in Montana, but the illness is in fact the most common infection that can spread from animals to humans in the world.
A bacterial infection, Brucellosis is most often transmitted to people via unpasteurized milk, but the bacteria can also be inhaled or acquired through contact with an infected animal. Though over half a million new cases are reported worldwide annually, organizations like the Centers for Disease Control suspect the disease is under-diagnosed and under-reported.
Diagnosis of Brucellosis infection in humans is often not an easy matter, since the symptoms, which include high undulating fevers and joint and muscle pain, often come and go for no apparent reason, and mirror the symptoms of several other diseases. In the United States, diagnosis is even less certain, since the disease has mostly been eradicated among humans and the domesticated animals we come in contact with. But the disease nevertheless persists, and could be more pervasive in this country than the medical community and the general population realizes.
Fifty-seven-year-old Diana Zambory of Newport, North Carolina, was diagnosed with Brucellosis in August of 2006. But she had been sick in an off-and-on manner, and seeing doctors as a result, for a year previous to the precise diagnosis.
“Of course, they weren’t going to be looking for something like [Brucellosis],” Zambory, referring to her initial doctor’s visits, told the Pioneer in February. “I also carry Hemochromatosis, a condition in which your body absorbs too much iron and does not eliminate it.” Zambory said that though she was treated for the Hemochromatosis condition, she kept getting sicker and sicker. She finally wound up in the hospital.
“I ended up losing 30 pounds in two weeks,” said Zambory. “I couldn’t stand up straight. I had a tremendous amount of back pain.” Because she had been suffering from night sweats for a long time as well, doctors even speculated that their patient was suffering from severe menopause, but Zambory said that idea was quickly cast off. After being released from the hospital without a firm diagnosis of her condition, Zambory continued her search for answers and relief.
“It wasn’t getting any better, no matter what doctor I went to, or what they did,” she said. Finally, one physician decided to delve a little deeper into Zambory’s mystery illness.
“I want to know exactly where you have lived in your life,” the doctor, who was an internist, asked Zambory. One of the places Zambory had lived was Connecticut, and the internist said, “You know what? We are going to check you for Lyme [disease].”
Lyme disease, named for Lyme, Connecticut, where the disease was somewhat endemic in the 1970s, is another bacterial infection transmitted to humans from animals: in the case of Lyme disease, the illness is transmitted to humans [and deer] by ticks, which acquire the bacteria from rodents like white-tailed mice. Lyme disease is one of the conditions whose symptoms mirror those of Brucellosis. Zambory said that the tests the internist ran on her for Lyme disease “came back with a positive hit,” and she was then sent on to an infectious disease doctor for further testing.
But Zambory said that the new doctor told her that a positive hit on on Lyme disease test “could mean 15 different things.” So testing of a more categorized nature was then put on Zambory’s agenda. Within six weeks of the new battery of tests, the new doctor told her she had tested positive for the Brucella Abortus bacteria: Zambory had contracted brucellosis.
“What is that?” a bewildered Zambory asked the doctor, who explained that her condition was a disease most typically found in cattle. The disease was first noticed by British physicians in the 1850s during the Crimean War: it also became known as Crimean Fever, Malta Fever, and Undulant Fever before being referred to as Brucellosis, after the relationship between the bacterium and the disease was established. By 1910 or so, pasteurization of milk began to greatly reduce the number of infections in humans, but the battle against the disease in cattle herds continued well into the 1940s, when the United State Department of Agriculture declared Brucellosis to be the most important bacterial zoonotic (transferable from animals to humans) disease present at that time, harming both animals and people that worked with them. The disease was largely eradicated in American cattle herds by the 1960s, but many other animals, both wild and domestic, can acquire the infection, and it remained active, though largely forgotten by the medical community. But Zambory had luckily crossed paths with the right physician, and doctor and patient next began the search to learn how she had in fact acquired Brucellosis.
“I live in a wooded area, and I also used to hunt,” said Zambory. “So we determined that somewhere along the line I had to have nicked myself cleaning infected deer, or had a tick that was infected.” Zambory and the doctor then began planning treatment for the symptoms of her infection; once acquired, Brucellosis cannot be cured. The severity of the symptoms depends largely on how quick the infection is properly treated. High doses of strong antibiotics are administered to keep the bacteria at bay, but with Zambory being allergic to some antibiotics, this approach had to be a careful one. Zambory said, though, that the doctor prescribed the right antibiotics in the right doses to keep her infection manageable.
“I’m still alive and kicking,” Zambory said. “As long as I’m staying on the antibiotics, I don’t have symptoms. But if I go off the antibiotics…within a week, all my blood tests start going haywire…I start going downhill really quick.” Zambory said that if her Brucellosis does act up, joint pain starts to set in, and so do headaches. She gets extremely tired. But she has been able to stay on top of the infection for the most part, and has continued to work for the same employer for well over a decade.
“There are times when I think my system gets a little bit out of whack, but fortunately I work at a great place, and all through this process they’ve worked with me wonderfully,” said Zambory, who is a full-time custodian at Carteret Community College in Morehead City, North Carolina. She is even somewhat of a “test subject” for a teacher at the school who has begun to do his own research on the disease: sometimes she visits the classroom, and his students get to see the effects the infection inflicts upon a human being through Zambory’s experiences.
Zambory said she thinks it’s highly likely that there are many people undiagnosed, or misdiag-nosed, when it comes to Brucellosis infection in the human population of the United States today. In Zambory’s case, her doctor, who is also the closest physician to her that is familiar with the disease, is in Greenville, North Carolina: Zambory travels more than two hours to see this doctor, who has more than a dozen other Brucellosis patients.
“Fast diagnosis is very important…it took quite some time before I was diagnosed,” she said, “and it took my persistence that something was wrong. But the quicker you can get the treatment, the less damage you are going to have.” Zambory said she hopes that more doctors will become aware of the human aspect of the illness, and that more and better information regarding Brucellosis infection in humans becomes available sooner rather than later, as well as more tools to detect the disease.
“The sooner the better…currently there are only two possible tests to determine if we have it,” Zambory told the Pioneer. “Honestly, I’d like to see a lot more research to enable better testing—cheaper testing—so more people can be tested. I also think if we can get the proper information out there, it will be better. You can survive it…the object is to find it first and then treat it properly.”