I needed a tetanus shot yesterday after a gardening accident involving my arm and a very spiky cactus. Like many people, I hate needles, but I'd rather suffer the jab than take a risk with this quite awful, and often lethal, disease.
We have several vials of tetanus vaccine in the Commonwealth Serum Laboratories (CSL) Collection. CSL was established in 1918 when it became clear that Australia's isolation, combined with the global disruption of World War I, demanded that we become self-sufficient in medicines and vaccines for the sake of public health. Like most vaccines, the anti-tentanus vaccine includes deactivated pathogen that doesn't cause illness, but still triggers the immune system into battle mode. The resulting antigens can respond quickly to destroy any active tetanus bacteria that enter the body and prevent us from developing full-blown tetanus.
A group of Clostridium tetani bacteria, responsible for causing tetanus in humans
Image: Centre for Disease Control
Source: Centers for Disease Control and Prevention's Public Health Image Library
When I was a kid I thought you caught tetanus from rusty nails, since standing on a rusty nail was the most common reason people went for a tetanus shot. It's not, of course - it's caused by a rod-shaped bacterium called Clostridium tetani. C. tetani is a common, free-living bacterium that flourishes in anaerobic (or oxygen-free) enviroments... such as the deep wound caused when you stand on a rusty nail. Once in there, the bacteria release a toxin called tetanospasmin which causes devastating muscle contractions and spasm. The infection is also known as 'lockjaw' since the first muscles to be affected are often the large chewing muscles. Tetanus is lethal in up to 45% of cases.
So on that cheery note, as summer approaches and you ditch your winter shoes for summer flip-flops, and spend more time outside near rusty nails, perhaps it's time for a tetanus booster?