Mosquito Empires: Ecology and War in the Greater Caribbean, 1620-1914
J. R. McNeill
Cambridge University Press, 2010
$29.24 (soft cover), 371 pages

If Churchill had stayed a few weeks longer in 1895 to observe the Spanish forces in Cuba fight the rebels, he might never have lived to confront Hitler in 1940. One sixth of all soldiers sent from Spain to fight in Cuba’s War of Independence died of the dreaded yellow fever within months of arrival.

In Mosquito Empires, J.R. McNeill argues that the development of the sugar cane economy changed the ecology of the Caribbean, creating the conditions for the mosquitoes that carried the yellow fever and malaria viruses. The mosquitoes are thought to have crossed from Africa on the slave ships that provided the labour essential for the large plantations.

The sugar cane economy and mineral resources made Spanish possessions a tempting target for three centuries. Ironically, only when Spanish colonists revolted, forcing Spain to use troops without the “differential” immunity gained from having already fought yellow fever in childhood or survived an attack in later life, would these riches be lost.

McNeill uses Haiti, so familiar to Canadians over the past twenty years, as an example several times to illustrate the impact of yellow fever. Irish may curse Cromwell’s brutal repression of Ireland but Cromwell no doubt cursed the scourge that caused his invasion of Santa Domingo to fail as yellow fever swept away more than half his 9,000 soldiers.

Colonizing efforts failed for similar reasons. A little known Scots colony in Panama at Darien failed because of yellow fever. Two thousand of 2,500 died.

Cartagena, in present day Columbia, was the scene of a major British defeat in 1741: of 8,000 troops, brought by a fleet of 186 ships, manned by 15,000 sailors and escorted by 29 ships, less than 3,000 soldiers survived after yellow fever took its toll. Spanish casualties, thanks to differential immunity, were between 200 and 600.

The Spanish tactic of surviving long enough for yellow fever to kill off invaders was even more evident in the short-lived British success at Havana, Cuba in 1762. Thirty warships of 11,000 British regulars laid siege to Havana. Yellow fever put the British in jeopardy until 4,000 fresh faces from the New England colonies brought a successful conclusion to the siege but nothing else. Not enough healthy soldiers remained to hold Havana, let alone carry on as planned to seize Louisiana.

McNeill suggests Havana losses limited the number of British troops available to deal with the Pontiac uprising, resulting in the Indian treaty so unpopular with the British colonies in the Americas.

The “Great” Napoleon’s plans for Louisiana were also scuppered by yellow fever. Haiti was the graveyard for an army of over 60,000. Over 80 percent died mostly from yellow fever between arrival in 1802 and departure of survivors in 1803. The British were not exempt. From 1793 to 1798, British forces totaling 27,000 in Haiti suffered 60-65 percent losses to yellow fever. John Simcoe, a significant name in Ontario history, was one of the British survivors.

Malaria must not be overlooked. Indeed, the success of the American forces at Yorktown is related to the malaria that affected Cornwallis’ army in its campaign in the Carolinas. Both North and South Carolina shared many of the conditions and had the same carrier mosquitoes that plagued the Greater Caribbean. The defeat at Yorktown led to American Independence and flight of so many Loyalists to what is now Canada.

Thus mosquitoes played a part, indirectly, in forcing an important migration that changed the character of our country.

The French effort to duplicate their Suez success with a Panama Canal was primarily defeated by yellow fever. However yellow fever itself was defeated by the preventive measures developed by the U.S. Army Yellow Fever Commission headed by Doctor Walter Reed. Created to deal with the threat to American troops occupying Cuba after their 1898 victory over Spain, the rigorous and expensive preventive regime imposed by Doctor Gorgas made possible the American construction of a Panama Canal, affecting Canada’s future naval requirement.

McNeill does readers a service in vividly bringing to life a “250 year era in which pathogens and people were co-regent over human affairs in the Greater Caribbean.”

Roy Thomas, MSC, CD, MA (RMC), served a year in Haiti.