Bordetella parapertussis evolved in a host population that had already developed immunity to "B. pertussis", where being able to evade "B. pertussis" immunity was an advantage. Two lineages of "B. parapertussis" have been described. The first infects humans and is responsible for a minority of cases of the disease pertussis (also known as whooping cough). The second, ovine, lineage causes chronic nonprogressive pneumonia in sheep. Both lineages are thought to have evolved from a "B. bronchiseptica"-like ancestor. This disease can be symptomatic or asymptomatic and may predispose hosts to secondary infection. Bordetella parapertussis Bordetella parapertussis is a small Gram-negative bacterium of the
Riggs' disease Riggs' disease Riggs' disease, also known as pyorrhea of a toothsocket or gingivitis expulsiva, is a historical term for periodontitis (gum disease), The condition was described as a purulent inflammation of the dental periosteum. It was named after American dentist John Mankey Riggs (1811–1885). Riggs' disease was said to produce the progressive necrosis of the alveoli and looseness of the teeth. The teeth may become very loose and fall out of the sockets. Mark Twain wrote briefly about Riggs' disease in his short essay, "Happy Memories of the Dental Chair", in which he claims to have been examined by Dr.