pubmed-article:6736642 | pubmed:abstractText | In 1980, an outbreak of a mild illness involving twenty pupils and four adults in a boys' boarding school was identified serologically as psittacosis. Intensive epidemiological investigations did not uncover the source. It is suggested either that sources of chlamydia other than avian exist, which may produce a milder illness than the avian type, or that human-to-human spread of a mild form of chlamydiosis occurs. | lld:pubmed |