A study of twins shows that genes play a role in ear infections
Like many physicians, Margaretha L. Casselbrant suspected that some children have a hereditary predisposition to middle ear infections. Unlike most other physicians, she set out to prove it systematically.
In 1983, the otolaryngologist began a painstaking, 17-year routine of collecting ear-infection data on same-sex twins and triplets. Casselbrant examined 168 sets of twins and 7 sets of triplets at least once every 2 months, plus whenever they had an earache. She recorded occurrences of excess fluid in the ear and cases of middle ear infection—otitis media—and prescribed a standard course of antibiotics when needed.