Contagion: How Commerce Has Spread Disease

Michael Worboys praises a history of global disease, and attempts to control it


Reviewed by: Michael Worboys
Author: Mark Harrison
Publisher: Yale University Press
Price (RRP): £25


A decade ago, the world was gripped by fear of a global epidemic of SARS. The first case was in China in November 2002, yet just four months later this highly contagious disease had spread across the world, carried by business people, tourists, migrants, sailors, and perhaps in the cabin air of jets and ships’ holds.

Government responses varied, from the imposition of strict sanitary barriers, through regimes of inspection and surveillance, to doing very little. There were warnings that the economic consequences of restrictions on movement might be worse than the epidemic, damaging trade, public health and living standards. Commentators pondered whether SARS was the first modern ‘global epidemic’, the product of the new era of globalisation.

In this book of impressive range and originality – the new global history at its best – Harrison demonstrates that it was no such thing, showing that the movement of people and goods has been associated with the spread of disease for centuries. He also reveals that the policy issues raised by SARS echoed those faced by governments, traders and doctors in previous transnational epidemics – an aspect of these well-chronicled events that historians have previously ignored.

Two diseases dominate the narrative: plague and yellow fever. From the Black Death onwards, the great fear of plague meant that strict sanitary barriers were the expected response. Yet the measures that were used, and when and how they were implemented, varied across time and space, even between ports in the same country. Nonetheless, Harrison identifies clear shifts, as in the 18th century when support for quarantines waned and controls moved to the conditions in ports and on transports, where infection might spread.

Politics, diplomacy, economy and trade and medical knowledge shaped this change, as they did in the 19th century when a plague pandemic began in China. Policy response was again mixed, though there was convergence to new liberal and scientific methods focusing on risk management.

Responses to yellow fever followed a similar trajectory. The earliest epidemics were in the Americas, where control was attempted through quarantines. Sentiment changed around 1800, as opinion formed that they were a relic of an unenlightened age and worse than the evil they purported to remedy. New epidemics after mid-19th century in central America brought calls for the return of quarantines and the US into the new international sanitary diplomacy. Soon policy coalesced around a ‘third way’ between quarantine and a free trade in germs.

Also important was the knowledge that yellow fever, like plague, was insect-borne and not transmitted person to person. This raises an interesting topic for speculation: how the history of disease and commerce would have differed if plague and yellow fever had been highly contagious like SARS.


Michael Worboys, University of Manchester