Even if he wasn’t thinking specifically about tularemia, Hans Zinsser knew well the danger that surrounds us. He cynically observed that “however secure and well-regulated civilized life may become, bacteria, Protozoa, viruses, infected fleas, lice, ticks, mosquitoes and bedbugs will always lurk in the shadows ready to pounce when neglect, poverty, famine or war lets down the defenses.”
The Vineyard doesn’t need neglect, poverty, famine or war to make us vulnerable. We have rabbits. Rabbits are just one of the hosts for the organism Francisella tularensis, the bacteria that causes tularemia, which is also sometimes called rabbit fever.
However, it wouldn’t be fair to blame only the bunnies, since there are other species that promote pandemic panic. Vectors of tularemia also include some birds, fish, reptiles, invertebrates and mammals. Ticks, mosquitoes and deerflies are common insect carriers. Nor are you safe if there is no animal about, since this brutal bacterium can persist in water, on grasslands and in haystacks and hay bales for even a few weeks.
Tularemia is not a new problem. In 1911, this bacterium was discovered in squirrels in Tulare County, California, thus providing the second part of its scientific name. The first, Francisella, honors Edward Francis, who studied this species. Since the early part of the last century, it has been observed and identified in all but one state (Hawaii).
Martha’s Vineyard, though, has a special place in the hearts and minds of those that study this disease. Though the states of Missouri, Kansas, Arkansas and Oklahoma can claim more cases of the disease, the Island does hold the honor of the most and only outbreaks of the most deadly pneumonic strain of the disease.
The two primary ways to contract tularemia are though airborne inhalation or direct contact. The pneumonic form is the most virulent and deadly. In fact, this bacterium is one of only six Category A High Priority Biological Welfare agents as classified by the US Government. Only 10 individual tularemia organisms are needed to cause illness, and its airborne nature provides opportunities for it to disperse widely. An outbreak of tularemia occurred during WWII during the Battle of Stalingrad. Opinions varied as to whether it was a natural outbreak or an intentional release by the Soviets as a biological weapon.
Take care when touching any live or dead animal. Studies of the Island cases have shown that landscapers are more likely to contract this disease, owing to the fact that they can mow over animal carcasses in the course of their work and breathe in the aerosol bacteria. An infected insect bite can also infect, as can eating or drinking contaminated food or water.
Most folks that do get tularemia survive — the fatality rate is two per cent. Flu-like symptoms usually result in three to five days, although up to 14 days is possible, from the pneumatic version, while skin lesions can occur when there is contact. A course of treatment of antibiotics is usually what doctors prescribe. May through September is the time that most infections occur, so be wary and be warned.
With all of this doom and gloom, it is not surprising that E.O. Wilson noted “Bacteria are the dark matter of the biological world.” But to be fair, not all bacteria are bad. Some make cheese, break down sewage or are great for your gut. Physician and author Martin Fischer got to the point when he said, “Bacteria keeps us from heaven and puts us there. “
Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown.