aedes aegypti – the mosquito that transmits yellow fever
The colonists who went to Jamaica in the 17th and 18th centuries were aware of many of the risks to their health but not of the causes. Much has been written about the reasons why white society in Jamaica never became established to the same extent as it did in North America in spite of the fact that the Caribbean islands were regarded as part of the same territory.
It is notable that of the early colonists who arrived with Penn and Venables from 1655 onwards few had descendants still on the island a century later. Very many marriages were terminated within a short time by the death of one partner. Infant and maternal mortality even by the standards of the time was shockingly high, and more than one colonist died at sea fleeing the island for the sake of their health. Of the eight children of the Rev William May featured in an earlier article only one survived to full adulthood, with two sons aged fifteen and twenty dying at sea on their way to Boston “for the recovery of their health”. Young girls seem to have married earlier on average than their equivalents back home in England, and it is likely, quite apart from the shortage of young white women in Jamaica, that this was at least in part an attempt to ensure the production of children before their parents’ anticipated early death. Visitors to the island noted with shock that few of the tombstones recorded Islanders who had made it past their early thirties.
The reasons for the very high infant mortality included waterborne infections such as diarrhoea and dysentery, measles, smallpox, whooping cough, and especially in the case of infants born on the plantations to enslaved mothers infantile tetanus (known as lockjaw). This disease whose spores are transmitted through animal faeces nearly wiped out the population of the Scottish island of St Kilda in the 19th century, until the local minister studying a course on midwifery prevented the anointing of the baby’s cord with sheep dung. On the Jamaican plantations where women carried baskets of dung on their heads to manure the sugar cane, such knowledge and choice was unavailable. There is no record of the number of babies who died in this way but it must have been high.
Infections such as measles, smallpox and whooping cough were no respecters of colour or class but there is evidence of appallingly high mortality among slaves newly arrived in Jamaica. Their health already compromised by dehydration, poor food, lack of fresh air or exercise and suffering from grief and depression, those on the lower tiers of a slave ship spent the voyage unable to avoid the urine and faeces of those above them. If they survived the voyage they too easily succumbed to epidemic diseases on arrival. It was generally the practice to “season” new arrivals allowing a period of acclimatisation often by working on the pens tending livestock or producing provisions before they were put to work in the cane fields or at the more skilled and exhausting tasks in the boiling houses.
Major epidemics killed white settlers and slaves alike, with regular outbreaks of yellow fever, measles, smallpox and yaws all of which were highly infectious. There is evidence that on some plantations it was realised that the slaves themselves were better at treating yaws, with which they were familiar from their home countries, than the European doctors who prescribed mercury itself a poison and used by them to treat the related condition of syphilis.
Yellow fever had probably arrived in the West Indies from Africa by the mid seventeenth century. Like malaria it is dependent for its transmission on mosquitoes breeding in stagnant water, both then present in abundance in Jamaica. The clay pots used in sugar production when broken were cast down and provided small pools of water; hurricanes and earthquake tsunami created larger bodies of water ideal for breeding.
Following the disastrous earthquake of June 1692 a correspondent of Sir Hans Sloane wrote on the 23rd of September, “We have had a very great Mortality since the great Earthquake (for we have little ones daily) almost half the people that escap’d upon Port-Royal are since dead of a Malignant Fever, from Change of Air, want of dry Houses, warm lodging, proper Medicines, and other conveniences.”
Another wrote “The Weather was much hotter after the Earthquake than before; and such an innumerable quantity of Muskitoes, that the like was never seen since the inhabiting of the Island.”
In addition to infectious illness with high mortality Jamaica’s inhabitants had to contend with problems caused by ticks and jiggers. Blood sucking ticks particularly attack bare flesh around the legs and infected bites could lead to more serious problems. Jiggers, or chigoe fleas, bore into the feet to lay their eggs and were particularly problematic for anyone without shoes, which of course was most of the enslaved population as well as some poor whites. It was important to remove the jiggers early in their life cycle using a specially designed knife, and many cases of lameness among slaves were attributed to the lesions from untreated jiggers. They could also attack the hands, and any part of the person exposed to the ground, such as legs or buttocks. Many plantations carried out weekly hand and foot inspections.
Europeans arriving in Jamaica recognized smallpox and dysentery, measles and whooping cough but yaws, tropical ulcers, the dry bellyache and miscellaneous fevers were new to them. Most were infections against which there was little remedy but the dry bellyache should have been avoidable by the mid-eighteenth century when its cause was understood to be lead poisoning resulting from the stills used for making rum.
Benjamin Franklin “wrote about lead poisoning on several occasions, in particular about a disease known as the dry-gripes (or dry-bellyache) that had plagued Europe and the colonies for years….in 1723 the Massachusetts colonial legislature passed a bill outlawing the use of lead in the coils and heads of stills. Observance of this law led to vastly decreased incidence of the dry-gripes, as the population drank less and less lead-contaminated rum.” 
In 1745 Thomas Cadwalder had drawn attention to the extreme cases of colic ‘West India dry gripe’ that were caused by the use of lead piping in rum distillation, but it seems nothing was done and it is not clear when the use of lead was reduced in Jamaica, with large scale illness and death among the garrisons and in the navy still occurring at the end of the eighteenth century. The better off colonists avoided the worst of this by drinking imported claret, brandy or Madeira as well as rum, but excessive use of alcohol leading to liver damage further weakened their ability to withstand illness and live to see old age.
One notable exception was Jane Gallimore born about 1664, who outlived her husband Matthew Gregory by nearly forty years and whose burial record in St Catherine in 1754 gave her age as ninety. Mary Bailie was buried on 22nd July 1756 when her age was recorded as ‘about 95’.
Many colonists chose not to risk the hazards of Jamaica once they had established their plantation, or made their fortune as merchants and left the island for ever hoping thereby to live a long and healthy life ‘back home’.
 Richard B. Sheridan, Doctors and Slaves, Cambridge University Press, 1985, reprinted 2009, pp.86-7
 Philosophical Transactions of the Royal Society, 1694, 18, pp.78-100
 Lisa Gensel , The Medical World of Benjamin Franklin, Journal of the Royal Society of Medicine, Vol. 98, No 12, pp. 534-538