3.3.2 Mode of transmission of tetanus
People can get tetanus through exposure to tetanus bacteria (Clostridium tetani) which are always present in the soil. The bacteria can be transmitted directly from the soil, or through dirty nails, dirty knives and tools, which contaminate wounds or cuts. A newborn baby can become infected if the knife, razor, or other instrument used to cut its umbilical cord is dirty, if dirty material is used to dress the cord, or if the hands of the person delivering the baby are not clean. Unclean delivery is common when mothers give birth at home in poor communities, but it can be prevented by skilled birth attendants (Figure 3.2).
The disease is caused by the action of a toxin produced by the bacteria, which damages the nerves of the infected host. This toxin is produced during the growth of the tetanus bacteria in dead tissues, in dirty wounds, or in the umbilicus following unclean delivery of the newborn.