The first cholera pandemic

Cholera morbus was a familiar hot-season illness in lower Bengal. In 1817 it began earlier than usual and was more widespread. Later summaries, such as a 2010 history of cholera in Iran, place the start at Jessore, near Calcutta. J. C. Peters, a New York physician who traced the outbreak around 1866, put its origin in the Ganges delta and found it at Kishnagur in May and June, at Patna by 11 July and in Calcutta in the first week of August. It reached Jessore on 28 August. Peters also noted that 1817 was the year of a Hindu festival held every twelfth year, when pilgrims crowded holy river sites such as Saugor Island below Calcutta, which he thought one of the first centers.

In November it struck the army of 90,000 men that the Marquis of Hastings had in the field against the Marathas, after some 10,000 people had already died in Allahabad. It spread first among camp followers and then through the whole camp. Men who deserted to escape it died along the roads for miles around.

From Bengal it moved with river traffic, markets and pilgrims. It was in Sylhet by 17 August and in Chittagong by 23 August, and went on to Arracan and Rangoon. Bombay suffered severely in 1818 and 1819. In 1821 British troops sent from Bombay carried it to Muscat, and it passed up the Persian Gulf to Bushehr and Basra, where Peters put the dead at 15,000 to 18,000 in 18 days.

Inland, the disease passed through Shiraz, where by Peters's account 6,000 people died in 18 days, and on to Isfahan and central Persia. A Persian army that had just defeated a Turkish force near Baghdad lost 2,000 soldiers to it in one march. Two years after reaching Bushehr, cholera crossed into Russia along the Caspian coast. By then it had also reached the Far East.