Panum's study of measles in the Faroe Islands

The first measles cases appeared in Tórshavn on 4 or 5 April 1846, the first outbreak in the Faroe Islands since 1781. By mid-September about 6,000 of the 7,782 islanders had been ill, and at least 102 had died of measles or its sequelae. The Danish government sent Peter Ludwig Panum, born on Bornholm in 1820 and newly qualified in Copenhagen, to investigate and control it.

The islands suited the work. Fjords separated the villages, and their limited contact with one another let Panum work out, in most cases, where and when the first person to fall ill had been exposed. He spent five months there, treated about 1,000 patients and studied 52 villages. In each he found the first case and counted the days to the next ones. He concluded that the infection gave no symptoms for 10 to 12 days and that the rash appeared on the 14th day after exposure. Ten men whose only shared contact had been a whale drive all broke out in the rash on the 14th day after it.

At Fuglefjord, on Østerø, a farmer's daughter had just recovered. Panum asked the day her rash had appeared, pointed in the almanac to the 14th day after it, and told the family to mark the date. Called back ten days later, he learned that the rash had appeared that day on all nine others in the house.

He also asked who had escaped. Of the many old people who had had measles in 1781, he could find none who caught it again, and he saw 98 of them himself. Among some 6,000 cases, about 1,000 of which he treated himself, he found none where a miasmatic origin could be supposed; the disease passed from person to person and from village to village, by contact or on clothing. Fifteen places kept measles out entirely by cutting off contact with infected villages. His report appeared in the Danish journal Bibliothek for Laeger in 1847.