However, the city's trading status meant it suffered from an outbreak of bubonic plague from 1663 to 1666, supposed to have come from Algiers to Amsterdam. (The plague also broke out in the trading center of London in June 1665.) Though it had little initial effect, the impact grew in autumn 1663 and in 1664. The wife and youngest daughter of well known collector of paintings Jan J. Hinlopen, as well as Rembrandt's partner Hendrickje Stoffels, fell victim to it that autumn. According to Samuel Pepys, for a few weeks at the end of 1663, ships from Hamburg and Amsterdam were quarantined for thirty days. In 1664, 24,148 people were buried in Amsterdam. More than 10% of the population died in this period - everybody that came into contact with the plague was at risk. At the time people assumed the plague was caused by the digging of new canals.