With the unseasonably warm weather in February, I started over-planning our garden early this year. By the time I get to it, of course, time and money available will have pruned it considerably, but at the beginning of the year every green and growing thing seems possible.
I was sitting amidst my pile of gardening magazines—Fine Gardening, Horticulture, Organic Gardening and all those “special gardening issues” one finds at the check-out counter—when I happened across an item that took the green right out of my thumbs. Right there in the April 2011 issue of Fine Gardening on page 26 was the startling news: Legionella longbeachae, the bacteria responsible for Legionnaires’ disease, has been found in compost and potting soil! Holy gladiolas, what will they think of next? And my wife and I are faced with having to spread yards of mulch following the removal of many weather damaged evergreens last year. Thanks to the alert in Fine Gardening magazine I will make sure we are wearing gloves. But still . . . Legionella longbeachae! That’s the culprit in Legionnaires’ disease! Yikes.
Like most Americans, I became aware of Legionnaires’ disease in the summer of 1976 when reports of an outbreak of an unknown but very serious illness was making the news. (Time magazine referred to it as “the Philly Killer.”) Eventually, over 220 mostly American Legion members attending a bicentennial event in Philadelphia were stricken with chest pains and admitted to hospitals around the country. The infection from the unknown microorganism was so bad that thirty-four people perished. Nobody knew how or why or what. There was serious talk of initiating a state-wide quarantine in Pennsylvania. No doubt the horrible Spanish influenza pandemic of 1918 was still on officials’ minds.
In fact, the Swine Flu was the first suspect but scientists quickly ruled that out as they did other suspected pathogens. Finally, in 1977, thanks to the persistence of Dr. Joseph McDade of the CDC, the bug revealed itself. Once identified, it was easy to control. America deeply breathed a collective sigh of relief.
In the case of the Philadelphia outbreak it had to do with a great environment for L. longbeachae in the Bellevue Stratford’s A/C system. As the bacteria became airborne it was inhaled and Legionnaires’ became infected. There have been notable outbreaks on cruise ships, too. Most outbreaks are associated with ventilation systems of some sort so potting soil caught me off guard.
Since at least 2000, gardeners in Europe and America, Australia* and Japan have been stricken with the Legionella bacterium. In most cases it was commercial potting soil or commercial compost. And what gardener doesn’t use at least a little of both? One notable case in Scotland was attributed to a man who had a cut on his hand—from his garden trowel, no less—and had nothing to do with his taking big whiffs of the potting mixture. However, that may be the case with other contaminations that have occurred among gardeners. At the same time—and this is very important—not all potting soil nor composted matter is infected. But since it will be difficult to determine which potting soil or mound of humus may harbor a problem, let us garden carefully with mask and gloves. No need to invite trouble.
Now I’m not sharing all this with you to keep you awake at night or keep you from your garden but because it highlights the amazing microbiotic world we live in. The bacteria that are “bad” for us mean us no harm; they’re just bad for us. They are just trying to survive but their survival comes at great consequence to us so we need to be prepared. That’s why we have, among other defenses, an immune system. Think of your immune system as the sign on the gate that says, “No pathogens allowed.” It’s only when that gate is left open that we get into trouble. So, go on a cruise ship and stay in a hotel and for heaven’s sake, keep gardening. Just remember to take your Vidazorb® and keep that gate closed.
After all: You are what you absorb™.
*Please note that in Australia that Legionnaires’ disease among gardeners was of such concern that the government now requires commercial potting soil to carry warning labels describing safe use practices. These include the wearing of a tight fitting mask, avoiding stirring up dust, and dampening soil and compost before use. Of course, washing hands even after wearing gloves is advised.
Additional resources on and information about Legionnaires’ disease: