The disease suddenly appeared in Hamburg, spreading so rapidly that more than a thousand people died in a few weeks. It swept through eastern Europe as an epidemic causing high mortality rates. It arrived in Switzerland in December, then was carried northwards to Denmark, Sweden, and Norway, and eastwards to Lithuania, Poland, and Russia. Cases of the disease were not known to occur in Italy or France, except in the Pale of Calais which was controlled by England at the time. It also emerged in Flanders and the Netherlands, possibly transmitted directly from England by travellers; it appeared simultaneously in the cities of Antwerp and Amsterdam on the morning of 27 September. In each place, it prevailed for a short time, generally not more than two weeks. By the end of the year, it had entirely disappeared except in eastern Switzerland, where it lingered into the next year. After this, the disease did not recur on mainland Europe.