In 1721, Boston experienced its worst outbreak of smallpox (also known as variola). 5,759 people out of around 10,600 in Boston were infected and 844 were recorded to have died between April 1721 and February 1722. The outbreak motivated Puritan minister Cotton Mather and physician Zabdiel Boylston to variolate hundreds of Bostonians as part of the Thirteen Colonies' earliest experiment with public inoculation. Their efforts would inspire further research for immunizing people from smallpox, placing the Massachusetts Bay Colony at the epicenter of the Colonies' first inoculation debate and changing Western society's medical treatment of the disease. The outbreak also altered social and religious public discourse about disease, as Boston's newspapers published various pamphlets opposing and supporting the inoculation efforts. Smallpox in Boston On 22 April 1721 the British passenger ship arrived at Boston from Barbados, after one stop at Tortuga, with a crew of sailors who had just survived smallpox. Customs' quarantine hospital at Spectacle Island was tasked with containing individuals who had contagious diseases, with a case of smallpox contained successfully the previous fall. But one of Seahorses sailors fell ill in Boston Harbor a day after arrival, and exposed other sailors to variola. Boston's water bailiff inspected Seahorse and discovered another two or three cases of smallpox in various stages before ordering the ship to leave the harbor. Despite the sailor being hurriedly quarantined in the lodging house where he fell ill, nine other sailors at Boston Harbor exposed to him came down with smallpox in early May. The sailors were quarantined on Spectacle Island's very-rudimentary hospital but staff and customs were unable to contain the virus. On 26 May Cotton Mather wrote in his diary: "The grievous calamity of the small pox has now entered the town." Boston's last smallpox outbreak had been in 1703, and a new generation of non-immune children and young adults was vulnerable. By June the town was faced with a major public health crisis and the religious public became increasingly worried that they were the subjects of divine punishment. Around 900 people fled Boston into the countryside, likely spreading the virus. The General Court, colonial Massachusetts' legislating body, moved from Boston to Cambridge at summer's end, but smallpox cases began appearing in Cambridge in August. James Franklin's The New England Courant was founded in August amid the outbreak and the issue of smallpox and preservation from it became front page news.