One of the preventive health measures, established back in the Middle Ages, was the construction of a facility for the isolation of passengers and goods, the so-called LAZARETTO. All the major maritime cities had lazarets, but unfortunately most of them have not survived. As an important port city, Dubrovnik took passengers into quarantine back in the 14th century. This oldest anti-epidemic measure, the decree on quarantine isolation, is certainly the most important contribution of Croats to the medieval medical culture.
On 27 July 1377, the Grand Chamber of the Republic of Dubrovnik passed a decision which for the first time in the world introduced quarantine as a measure of protection against the introduction and spread of infectious diseases, which was published in the so-called Green Book (Liber viridis), under the title Veniens de locis pestiferis non intros Ragusium nel districtum (Whoever comes from infected regions should not enter Dubrovnik or its territory). It was stipulated that neither the locals nor foreigners coming from infectious regions could enter the city if they first did not spend a month on the islands of Mrkan, Bobara and St. Peter next to Cavtat. In the 1397 decision it was decided that foreigners and their ships could not sail west of Molunat or east of the island of Mljet, and quarantine was decreed for them on the island of Mrkan, where a Franciscan monastery was located at the time, and on Mljet where there was a Benedictine monastery. The first quarantine took place in barracks, but solid stone buildings were erected later.
Because of the distance, as well as for strategic reasons, quarantine in the 15th century was moved closer to the city. At the beginning of the 15th century there was a lazaret on Danče in Dubrovnik. For this purpose, in 1430 some houses in Gradac were taken, and in 1457 construction of the lazaret and a church next to it on Danče commenced. Good organization of this lazaret enabled the complete abandonment of quarantines on the islands near Cavtat. The construction of a lazaret on Lokrum began in 1533. Although a large square lazaret was built, it was never completed or used for quarantine.
At the end of the 15th century, a decision was passed to build a lazaret in Ploče, at the site where land and sea trade routes met. Construction of the lazaret in Ploče commenced in 1590, while it was completed in 1642. The duration of quarantine was extended from thirty to forty days and health workers, the so-called kacamorti oversaw the implementation of and compliance with the provisions of the quarantine.
Moving the lazaret to Ploče signified the transformation of the institution from the framework of maritime medical services to a sanitary cordon towards the mainland. An impressive complex consisting of ten halls, and five internal courtyards between them, with two multi-level houses at the entrance and the end of the lazaretto (port authority and janissaries han) still attract attention from the land, and especially from the sea upon entering the harbour.
It is interesting to note that in 1808 the French established a health commission (commisione di sanita) which continued its activities during the Austrian rule, all the way until 1918. People popularly started to call the commission Sanitat. When a special company was established in 1967 for disinfection, pest and rodent control and deodorization jobs, it was called SANITAT, continuing through its name an ancient tradition.
Until 2013, SANITAT DUBROVNIK d.o.o. operated in the premises of the Lazaretto in Ploče, built more than 400 years ago for a similar purpose, which is unique in the world. SANITAT was established through a Decision of the General Assembly of the municipality of Dubrovnik on 15 October 1966 for performing disinfection, pest and rodent control jobs. During the Homeland War, the service for disinfection, pest and rodent control jobs gave a great contribution to the clean up of the battlefields and the liberated areas.