Malaria and Rome: A History of Malaria in Ancient Italy, Robert Sallares [reading a book TXT] 📗

regions with intense malaria themselves and outside observers to jump to the conclusion that malaria is not a major problem. The only legitimate inference to be drawn from such a conclusion, as in Ginanni’s case, is that it demonstrates a lack of understanding of the immunology of malaria—not surprising in an eighteenth-century author. It does not constitute evidence for any mildness or avirulence of the disease. The studies that were done at the beginning of the twentieth century showed that P. falciparum was common in the coastal regions of northeastern Italy alongside P. vivax and P. malariae, although P. vivax lasted longer than P. falciparum once eradication measures commenced. A survey in 1849

below). Greeks were present in the cities of Atria and Spina from the sixth century 

onwards (intermingled with Etruscans, other local Italic peoples, and later on Celts as well), who might well have carried with them genetic mutations related to malaria from their homeland in Greece, another area of endemic malaria. Consequently thalassaemia, for example, may already have occurred in northeastern Italy in the fifth century  even though the area did not yet suffer from malaria.

¹⁰⁰ In the province of Ferrara allele frequencies for b-thalassaemia mutations decrease from the Adriatic coast westwards, while in the province of Rovigo there is no such decrease (Barrai et al. (1984) ). In Ferrara, south of the river Po, marshy areas were largely confined to the east of the province, while in Rovigo, north of the Po, there were marshy areas throughout the entire province.

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14. Anopheles sacharovi, a very important vector of malaria in Italy and eastern Mediterranean countries. © The Natural History Museum, London.

concluded that 16.7% of the entire population of the province of Venezia suffered from malaria in that particular year.¹⁰¹

In recent times Anopheles sacharovi was common in certain foci of intense malaria around Ravenna, breeding in brackish water, although A. labranchiae was virtually absent from this region. Presumably in antiquity the hydrological conditions of the marshes around Ravenna were unsuitable for A. sacharovi, preventing this species, the most efficient vector of malaria in Mediterranean countries, from breeding in the area. Gilberto Corbellini and Lorenza Merzagora observed that the early Venetian writers on mal’aria (see Ch. 2 above) emphasized the importance of the mixing of fresh water and seawater for the generation of malaria. This shows that the modern ecology of the coastal regions of northeastern Italy, with brackish conditions favourable for A. sacharovi, already existed by the end of the medieval period. Among the more zoophilic species of Anopheles mosquito, A. maculipennis s.s.

prevailed to the north of Venice, while A. atroparvus (a secondary ¹⁰¹ Rausa and Romano (2000) and Hirsch (1883: 213–14) described the distribution of malaria in northern Italy in the nineteenth century.

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malaria vector in northern Italy), was common in the Po delta, and A. messeae also occurred in places. There certainly were plenty of mosquitoes in northeastern Italy in antiquity, since Martial mentioned the culices of Atria, another town in the same region, while Sidonius Apollinaris mentioned the mosquitoes of Ravenna. However, we may infer that these were predominantly not anthropophilic anopheline species, but zoophilic anopheline species or culicine mosquitoes. Culicine mosquitoes can breed in dirty water but do not transmit malaria to humans, although they are the vectors of the avian species of malaria.¹⁰² The Po delta, like other major Mediterranean deltas such as the Ebro in Spain and the Nile in Egypt, has increased in size substantially within the last three or four centuries, as a result of very extensive alluviation following that which had already taken place in antiquity. This process of alluviation, a very important theme to return to later, led to the abandonment of a number of towns which functioned as ports in various parts of the Mediterranean. For example, Strabo observed that Spina in the Po delta region, which was on the coast when it was founded, was ninety stadia inland by the first century . Similarly Luni on the other side of Italy was stranded in the same way, and malaria moved in, just as it did at Ravenna. Further south in Campania, the Greek colony of Cumae had a lagoon on its northern side connected to the sea, which provided a sheltered harbour when the colony was founded in the eighth century . However, by the end of the first century  the lagoon entrance had become silted up, destroying the harbour. Subsequently the lagoon started to fill in slowly from the north, until it was finally completely drained by Mussolini. These are all illustrations of a very widespread, long-running process of change. Virtually all the coastal regions of Italy were completely different in antiquity from the way they look today.¹⁰³ Thus the development of the coastal malarial environments of Italy as they appear today was a prolonged process which unfolded over a period of several thousand years.

In Lazio the delta of the River Tiber underwent a similar process ¹⁰² Martial 3.93; Sidonius Apollinaris, Letters, 1.8.2. to Candidianus. Neri and Gratch (1938) and Zamburlini (2000) discussed the mosquitoes of Ravenna and the Veneto. See also Christie and Gibson (1988); Veggiani (1973) and (1986: esp. 26) on malaria.

¹⁰³ Strabo 5.1.7.214C and 5.2.5.222C; Potter (1981: 7) on Spina; Laquidara (1989) on malaria at Luni; Vecchi et al. (2000) on Cumae. Spivey and Stoddart (1990: 24–6) described the changes in the coastline around Pisa and Populonia. Hunt et al. (1992) described one example of continuing erosion in Tuscany within the last millennium.

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of development. The history of the Roman port of Ostia, at the mouth of the river, in relation to malaria merits some discussion.

Ostia was probably founded to exploit salt deposits at the mouth of the Tiber.¹⁰⁴ It was probably not unhealthy to begin with, like Ravenna, because the salinity level was too high for