Members of the English colonies as well as English officials were proactive in establishing quarantine guidelines in order to protect the public. One of the earliest recorded examples of this was a quarantine established in 1647 by Puritans in order to prevent the spread of disease from ships coming from the Caribbean. In 1731 an act, entitled "An Act to Prevent Persons From Concealing the Smallpox", was passed. This act made the heads of households mandatory reporters for smallpox; these individuals were required to report smallpox in their house to the selectmen of the Massachusetts Bay Colony. Infected households would then be indicated with the placement of a red flag. In South Carolina, sentinels were to be posted outside infected households and infectious notices were required to be posted. In many colonies islands were set up to quarantine individuals coming in by ship. This decreased the chances of smallpox being introduced via trade or travel. By the late 1700s, almost all colonies had quarantine laws in effect in order to diminish the hugely damaging effects that smallpox could have on their communities.