After the first epidemics, preventive measures were installed, including a very active lazaret which issued patents of non-contagion for many ships plying the Mediterranean.
[2] The Black Death pandemic spread throughout Europe starting from October 1347, when a Genoese ship brought the plague to Messina in Sicily.
When the disease was discovered, the municipal authority of Mdina tried to isolate the crew, submerge the ship and burn its cargo.
[5] It was not until 1643 that Malta acquired a lazaret, installed on the island of Marsamxett bay, which was quite late and well after the lazaretto of Venice, opened in 1403, or that of Marseille in 1526.
The organization being well established and the port well stocked, the sanitary stopover in Malta will be often used and will participate in the Maltese economic development.
[6][7] The third epidemic began in September 1655 in a house near the "Porta Maggiore" (today the "Victoria Gate") near a place of anchoring of ships coming from the Levant.
The owner is said to have had contact with a crew member of an infected vessel, and to have transmitted the disease to his sister inhabiting Żejtun.
When the disease spreads to other family members, the authorities immediately take quarantine measures by isolating people in contact with the lazaretto.
[12] The disease first spreads slowly to Valletta before ravaging the countryside, and in particular the cities of Ħaż-Żebbuġ and Qormi where about 15% of their inhabitants died.
The plague soon spreads to the neighboring village of Żebbuġ where eleven people are infected with three deaths, including a girl aged 7.
[19] Significant research was carried out by Themistocles Zammit, who succeeded in isolating plague bacillus cultures from 15 of the 1,500 rats studied.