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

(1881: ix–xvii); Celli (1900: 177); Douglas (1955: 305); Levi (1945: 74). Viazzo (1989: 198, 212, 215–18, 289) described the healthiness of Alpine environments.

Balfour (1935: 329) stated that malaria was commoner below 250 metres above sea level in Greece, while Dobson (1997: 107) observed that the worst affected parishes in England were below 50 metres above sea level, while parishes above 400 metres were very healthy.

Ecology of malaria

61

breed there. These animals cannot be seen with the naked eye and enter the body through the mouth and nostrils in the air and cause severe diseases.³⁸

Varro’s animalia quaedam minuta appear to be the invisible particles of disease postulated in the atomic theory of Lucretius, as suggested by Phillips, rather than mosquitoes, or even less likely, the protozoa of malaria. This passage is unparalleled in ancient Latin literature and Varro’s idea had no practical consequences.³⁹ Nevertheless his recommendations are interesting, including the suggestion that unhealthy localities were better worked with hired labour rather than slaves.⁴⁰ This idea is significant for understanding the agricultural economy of the regions of Italy in which malaria was endemic in the past, as will be seen later.

Columella advised against siting farm buildings next to marshes, making a more direct reference to mosquitoes.⁴¹ He also noted that the water of marshes was pestilential, but only in summer, and Vitruvius also observed that the most pestilential places were healthy in winter.⁴² Antyllus and Athenaios both described marshes as pestilential in summer.⁴³ These texts introduce the very important question of the seasonality of malaria, which has recently been studied by Scheidel employing funerary inscriptions and modern ³⁸ Varro, RR 1.12.2: Advertendum etiam, siqua erunt loca palustria . . . quod crescunt animalia quaedam minuta, quae non possunt oculi consequi, et per aera intus in corpus per os ac nares perveniunt atque efficiunt difficilis morbos.

³⁹ Phillips (1982); Nutton (1983: 10–11) discussed Varro and Columella on marshes. He argued that Galen did take the ‘seeds of disease’ theory seriously as an explanation for some time, but eventually subordinated it to the humoral theory, in which a humoral imbalance was required for the ‘seeds of disease’ to have any effect.

⁴⁰ Varro, RR 1.17.3: gravia loca utilius esse mercennariis colere quam servis.

⁴¹ Columella, RR 1.5.6: nec paludem quidem vicinam esse oportet aedificiis . . . quod illa caloribus noxium virus eructat et infestis aculeis armata gignit animalia, quae in nos densissimis examinibus involant (And there should not be a marsh close to the buildings . . . because it throws up an evil odour during the summer heat and produces insects armed with dangerous stings, which swoop upon us in dense swarms.).

⁴² Columella, RR 1.5.3: deterrima palustris, quae pigro lapsu repit; et pestilens, quae in palude sumper consistit. Hic idem tamen umor, quamvis nocentis naturae, temporibus hiemis edomitus imbribus mitescit (Worst of all is marsh-water, which flows along with slow movements; and water which always remains in a swamp is pestilential. However this same water, although its nature is harmful, is tamed by the winter rains and becomes harmless.); Vitruvius, 1.4.4.

⁴³ Antyllus in Stobaios, florilegium 101.18: oÈ d† ‰l*deiß kako≥ m†n åe≤, qvrouß d† ka≥

loim*deiß (Marshes are always bad, and pestilential in summer.); Athenaios in Oribasius 9.2.10, ed. Raeder (1926–33): ƒpinoswtvrouß ojÎmeqa toŸß limn3zontaß ka≥ ‰l*deiß tÎpouß, ka≥ m3lista toı qvrouß, di¤ t¶n ånwmal≤an toı åvroß (We reckon that places with stagnant and marshy water are rather unhealthy, particularly in summer, because of the irregularity of the air.).

62

Ecology of malaria

comparative evidence.⁴⁴ In the early eighteenth century Lancisi described the succession of different types of fever in the summer in Lazio, first benign tertian fevers, then continuous fevers, then pernicious fevers at the time of the autumn equinox (especially if there were showers, clouds, and south winds), and finally long-running quartan fevers.⁴⁵ In nineteenth-century Rome there were no new cases of P. falciparum malaria from March to June inclusive, because of its temperature requirements for sporogony in the mosquito.

Any cases that developed during those months were recrudescences of previous infections. The annual epidemic broke out in Rome rather suddenly in July each year. The annual maximum number of cases was usually attained in Rome in August (but sometimes as late as October). This explains the significance of the dog-days, the period after the heliacal rising of Sirius (the hound of Orion and so the dog-star for the Greeks) in late July, as not only the hottest time of the year but also an extremely unhealthy season.⁴⁶ Theophrastus attempted to explain in climatic terms both the late summer peak of malarial fevers and the peak of gastro-intestinal infections that also occurred in the summer in Mediterranean countries. ‘During the dog days, even though the air is very hot, nevertheless south winds blow and clouds form and trees themselves become visibly fluid and a certain degree of fluidity spreads under the bark, as a result of which there are flows of sap in trees even at this time of the year, either because of the concentration of the fluid owing to reciprocal displacement or because of some other cause. This also happens in humans, and that is why the bowels become very loose at this time and fevers are very frequent, since bodies become fluid.’⁴⁷

Since malaria could take several months to be fatal, direct mortality from cases arising in August could be delayed until the winter.

The timing of the seasonal peak varied from place to place. At ⁴⁴ Scheidel (1996).

⁴⁵ Lancisi (1717: 42).

⁴⁶ Corti (1984: 665) commented on the attitudes of Italian peasants to the dog-star period in more recent times.

⁴⁷ Theophrastus, CP 1.13.5–6, ed. Einarson and Link (1976): ËpÏ g¤r tÏ £stron [sc. ƒn t∫

toı KunÏß ƒpitol∫] ka≤per Ôntoß ƒmp»rou toı åvroß, Òmwß ka≥ nÎtia pne∏ ka≥ nvfh sun≤statai ka≥ aÛt¤ t¤ dvndra diugra≤netai faner0ß ka≥ ËpÏ tÏn floiÏn aÛt0n diad≤dota≤

tiß ËgrÎthß, Òqen ka≥ Âoa≥ ka≥ kat¤ toıton tÏn kairÎn, e÷te oˆn sunelaunomvnou toı Ëgroı ka≥ åntiperist3sewß