disease 253
If we now consider the situation in antiquity, it may be postulated that it was a very
similar process, the spread of both falciparum malaria itself and its most important
vectors in the Mediterranean, Anopheles labranchiae and Anopheles sacharovi, on
board ships from North Africa and the Near East to southern Europe, as a result of
steadily-increasing contacts within the Mediterranean basin, which led to the creation
of the distinctive pathogen community of the Mediterranean by establishing falcipa-
rum malaria, its most important member, on the northern as well as the southern
shores of the Mediterranean (Sallares et al., 2004). This hypothesis is extremely prob-
able even if there is no way of directly proving it. Both Plasmodium falciparum and
its two most important Mediterranean vectors have temperature requirements that
would have excluded them from southern Europe during the Ice Ages; during the
glacial periods they would have been confined to North Africa and the Near East,
where the two mosquito species occupy a wider range of ecological niches today than
they do in southern Europe (Sallares, 2002; Sallares, 2006). The spread of falciparum
malaria to Italy had major consequences in some areas. For example, in Tuscany it
played a part in the decline of the coastal Etruscan city-states such as Vulci and
Cerveteri and led to a shift in human settlement to healthy areas away from the coast,
such as Florence and Arezzo (Sterpellone, 2002: 175–189).
In between falciparum malaria in the first millennium bce and chikungunya and
dengue today, there are many other historical examples that illustrate the importance
of increasing inter-regional contact mediated by humans for the construction of the
Mediterranean pathogen community. From 165 ce onwards the soldiers of the Roman
army of Verus returning from war in Mesopotamia brought smallpox in the form of
the so-called Antonine Plague westwards, firstly to Egypt and Greece and then to
Italy and the westernmost parts of the Roman Empire (Duncan-Jones, 1996;
Gourevitch, 2005; Rijkels, 2005: 22–76). Leprosy, which was not endemic in the
western half of the Roman Empire in antiquity, certainly followed the same path west-
wards in the medieval period, even if it did not have any particular association with
returning Crusaders (Roberts et al., 2002; Mitchell, 2011a). The question of whether
venereal syphilis, the “great pox,” followed Christopher Columbus across the Atlantic
to Mediterranean Europe from the western hemisphere is a matter of great contro-
versy, although the transatlantic theory still seems a possibility to the current author
(Harper et al., 2011). There is no doubt whatsoever that yellow fever did spread to
many coastal cities in Mediterranean Europe and as far north as Britain in the eight-
eenth and nineteenth centuries as a direct consequence of increased European contact
with tropical Africa and with central America, where yellow fever had already become
established. Spain was the most vulnerable country because of its proximity to Africa
and its close ties to central America. There were epidemics of yellow fever in Barcelona
in 1821 and 1870, for example, and most of the coastal cities of Spain were affected
(Betrán Moya, 2006: 133–139). However yellow fever also spread by sea to other
countries, striking Livorno in Italy in 1804 and Swansea in Wales in 1865, for exam-
ple. Although yellow fever could cause brief epidemics in summer in Mediterranean
ports, it could not become a permanent member of the Mediterranean pathogen
community because, in general, European winters are too cold for its principal mos-
quito vector, Aedes aegypti, to become endemic in Europe.
In passing, it should be noted that Spain was also affected by malaria, not only
coastal regions such as the Ebro delta and the areas of rice cultivation around Valencia,