America throughout the late-eighteenth and early-nineteenth centuries, the best-known examples being the 1793 Philadelphia yellow fever epidemic and outbreaks in Georgia (1856) and Florida (1888). Cholera and smallpox epidemics continued throughout the nineteenth century, and plague epidemics affected Honolulu and San Francisco from 1899 until 1901. State governments generally relied on the cordon sanitaire as a geographic quarantine measure to control the movement of people into and out of affected communities. During the 1918 influenza pandemic, some communities instituted protective sequestration (sometimes referred to as "reverse quarantine") to keep the infected from introducing influenza into healthy populations. Most Western countries implemented a range of containment strategies, including isolation, surveillance, and the closure of schools, churches, theatres, and public events. People were prevented from entering the Ashanti Empire at border checkpoints if they exhibited symptoms of smallpox. Those who discovered symptoms of the disease after entering Ashanti were quarantined in remote villages. In the 1830s, both the Ottoman Empire and Egypt established new quarantine systems. In 1831, Mehmet Ali of Egypt founded the Quarantine Board in Alexandria. In 1838, the Ottoman government installed the Supreme Council of Health, including the Quarantine Administration, in Istanbul. These two institutions set up permanent quarantines throughout the eastern Mediterranean, based on the western Mediterranean quarantine model. For example, at the port of Izmir, all ships and their cargo would be inspected and those suspected of carrying the plague would be towed to separate docks and their personnel housed in separate buildings for a determined period of time. In Thessaly, along the Greek-Turkish border, all travellers entering and exiting the Ottoman Empire would be quarantined for 9–15 days. Upon appearance of the plague, the quarantine stations would be militarised and the Ottoman army would be involved in border control and disease monitoring. International conventions 1852–1927 Since 1852, several conferences were held involving European powers, with a view to uniform action in keeping out infection from the East and preventing its spread within Europe. All but that of 1897 were concerned with cholera. No result came of those at Paris (1852), Constantinople (1866), Vienna (1874), and Rome (1885), but each of the subsequent ones doctrine of constructive infection of a ship as coming from a scheduled port, and an approximation to the principles advocated by Great Britain for many years. The principal countries which retained the old system at the time were Spain, Portugal, Turkey, Greece, and