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

genotype is encountered. Consequently an individual who has acquired immunity to all the genotypes prevalent in the region of domicile is still vulnerable to different genotypes existing in other areas. The experiments at Horton Hospital in England showed that artificial infection with a strain of P. falciparum from India, for example, gave no protection at all against subsequent infection with a strain of P. falciparum from Sardinia.³²

The relevance of all this to the plight of the Athenians outside Syracuse is that the fact that P. falciparum attacked many adults does not prove that it was a new disease then, either in Sicily or in Greece. It may simply have been the case instead that the Athenians and their allies encountered in Sicily a new strain of P. falciparum which was different from the strains to which they were accustomed in Greece. Nevertheless, Grmek’s identification of P. falciparum malaria in the marshes outside Syracuse in 413  should be retained. There is also evidence for malaria in Sicily in the fifth century  at Selinus, Camarina, and Akragas. Consequently it appears that malaria was widespread and severe in Sicily from at least the fifth century  onwards.³³ Later on Sicily became an important source of grain for the city of Rome. Undoubtedly it also supplied malaria to that city. The inevitable result of prolonged ³² Babiker and Walliker (1997); Gupta et al. (1994); Kemp et al. (1990); Walliker et al. (1987); Paul and Day (1998); Marchiafava and Bignami (1894: 93); Smith et al. (1995); Su et al. (1995); Covel and Nicol (1951); Freitas-Junior et al. (2000) explained the very high frequency of recombination in the var gene sequences of P. falciparum in terms of gene conversion between aligned var genes in the adjacent telomeric regions of heterologous chromosomes.

³³ Empedocles diverted two rivers to try to eliminate malaria from the vicinity of Selinus, according to Diodorus of Ephesus: to∏ß Selinount≤oiß ƒmpesÎntoß loimoı di¤ t¤ß åpÏ toı parakeimvnou potamoı duswd≤aß, ¿ste ka≥ aÛtoŸß fqe≤resqai ka≥ t¤ß guna∏kaß dustoke∏n, ƒpino[sai tÏn ∞Empedoklva ka≥ d»o tin¤ß potamoŸß t0n s»negguß ƒpagage∏n jd≤aiß dap¤naiß: ka≥ katam≤xanta gluk[nai t¤ Âe»mata (Since a plague afflicted the people of Selinus because of the evil smell of the adjacent river, causing death and making pregnant women miscarry, Empedocles had the idea of bringing two rivers there at his own expense. By mixing the waters he sweetened them.) (Diogenes Laertius 8.70). The reality of the drainage works is shown by fifth-century coins from Selinus (Pauly-Wissowa, RE II A.2, (1923), col. 1281). P. F.

Russell (1955: pl. facing p. 161) illustrates one of these coins. Servius’ commentary on Virgil, Aeneid 3.701, Greek Anthology, 9.685, and Suda s.v. m¶ k≤nei Kam3rinan (don’t move Camarina) mention malarial swamps at Camarina in Sicily. For Akragas see Ch. 4. 2 below.

Evolution of malaria

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exposure to intense endemic malaria in Sicily was the evolution of high frequencies of human genetic mutations giving some resistance to malaria. Besides b-thalassaemia and glucose-6-phosphate dehydrogenase (G6PD) deficiency, which are common in Sicily as in other Mediterranean populations with experience of endemic malaria (see Ch. 5. 3 below), the modern population of Sicily also exhibits a certain frequency (about 2%) of the sickle-cell trait (bS).

Haplotype analysis indicates that the sickle-cell trait reached Sicily from western central Africa. However, it is unclear whether this had already happened in antiquity, perhaps during the period of Carthaginian activity in Sicily, or during the time of the Roman Empire, as a result of the slave trade, or whether it happened later, as a result of the Arab conquests in the early medieval period.³⁴

Besides the G6PD mutations which are characteristic of Mediterranean populations, the principal African variant of G6PD

deficiency (A) also occurs in Sicily. This is further evidence supporting the hypothesis of gene flow from central Africa to Sicily.

The tenor of the discussion so far has been to suggest that none of the arguments that have been proposed in favour of a very late introduction of P. falciparum to southern Europe is convincing. On the contrary, the trend of the most recent scientific research is to suggest that P. falciparum is an extremely ancient pathogen which has been pursuing humans and their hominid ancestors for as long as they have been present on earth. The conclusions reached here so far are compatible with the opinion of Brunt, who did not find anything in ancient literary sources to suggest that malaria was ever regarded as a new disease in the classical period. The possibility of the emergence of new diseases was certainly explicitly considered in classical antiquity, particularly in relation to leprosy, as is demonstrated by lengthy discussions in Pliny and Plutarch.³⁵ However, no ancient Greek or Latin author ever suggested that the intermittent fevers now called malaria were a new disease. Nevertheless Brunt’s view yields a paradox that requires detailed investigation now. The paradox arises from the fact that the Etruscan cities in the Maremma and southern Etruria and numerous Greek colonies in the coastal regions of southern Italy were situated in locations so heavily infested with malaria in later times as to make it difficult to imagine how they could ever have prospered at all, ³⁴ Ragusa et al. (1988); Schilirò et al. (1990); Adekile (1992).

³⁵ Pliny, NH 26.1–6.1–9; Plutarch, Moralia 8.9.731b–734c.

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Evolution of malaria

if malaria had been present right from the start. According to Dionysius of Halicarnassus a major attraction of Veii, the important Etruscan city captured by the Romans in 396  supposedly after a siege lasting ten years, as a place to live was the healthiness of its site, since there were no marshes or rivers nearby which generated ‘bad air’:

The city of Veii . . . had air around it that was extremely pure and very good for human health, since there was no marsh nearby to generate oppressive and evil-smelling vapours,