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

grams or more below normal. A low-birth-weight baby who doesn’t ‘catch up’ has a puny immune system, and these children frequently die during childhood of all sorts of infections. The death certificate . . . may read diarrhoea or pneumonia, but the real cause of death was malaria of the mother.³⁴

This is how malaria can enormously exacerbate the effects of gastro-intestinal diseases on infant and child mortality without even being present in the children. Average birth weight of infants in fact increased significantly in areas of former malaria endemicity following modern eradication campaigns. Maternal infections with P. vivax may possibly reduce the severity of subsequent infections with P. falciparum during pregnancy, owing to immunological cross-reactions, but P. vivax itself causes birthweight reduction in all pregnancies, not just in primigravidae, in areas with endemic malaria. It has been estimated that up to 50% of low-birth-weight babies in some populations in tropical countries may be caused by ³² Lindsay et al. (2000).

³³ McFalls and McFalls (1984: 101, 107–8); Fried and Duffy (1996), discussed by Matteelli et al. (1997); Marchiafava (1931: 50–1) on placental malaria in Italy; Gilles and Warrell (1993: 46); Reuben (1993); Fried et al. (1998).

³⁴ Desowitz (1992: 118); Brabin (1992); Newby and Lovel (1995); and Brabin et al. (1996).

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maternal malaria.³⁵ In Sardinia, in areas where the transmission rate of P. falciparum malaria was extremely high, fertility rates were higher than in areas where the transmission rate was lower. This proves a degree of adaptation by women to intense malaria, as a result of both acquired and inherited immunity (e.g. thalassaemia and glucose-6-phosphate dehydrogenase deficiency in Sardinia), but it has to be remembered that overall mortality was much higher and life expectancy much lower in the areas with a very high transmission rate. Higher fertility was required to balance higher mortality. Even with such increments in fertility, the mortality profile of populations exposed to endemic malaria was extremely poor.³⁶

Besides the indirect effects on infants caused by maternal infection, P. falciparum malaria can also be present in infants and children themselves alongside gastro-intestinal infections. In Macedonia during the First World War it was observed that malarial infections readily coexist with typhoid fever, paratyphoid fever, and amoebic dysentery, for example. Of particular interest is the observation that when patients in Macedonia were infected with both typhoid fever and P. falciparum malaria, as was proved by examination of blood smears for malaria and microbiological techniques for typhoid fever, the clinical symptoms observed were principally those of typhoid fever. The implication of this with regard to ancient sources is that cases, for example in the books of Epidemics in the Hippocratic corpus, which look like cases of typhoid fever, could very easily have been infected with malaria as well, but this would not be apparent from the description given in the ancient text. Such dual infections are very likely to happen in areas where malaria is endemic. Malaria may also directly interact with gastro-intestinal infections, since there is some evidence that malaria suppresses the immune response to typhoid fever and other types of salmonella.³⁷ Malarial fevers do in any case strongly resemble the ³⁵ I. A. McGregor in Wernsdorfer and McGregor (1988: i. 757); Brabin and Piper (1997); Nosten et al. (1999) on P. vivax.

³⁶ Zei et al. (1990) observed that placental malaria is in fact more severe in women in areas of low transmission (and so less acquired/innate immunity) than in areas of high transmission (and so a higher degree of immunity).

³⁷ Armand-Delille et al. (1918: 79). Corvisier (1985: 117) lists six probable cases of typhoid fever in the Hippocratic Epidemics; Mabey et al. (1987). Urban et al. (1999) described one mechanism by means of which P. falciparum suppresses the human immune response to infection. Faccini (1984) discussed typhoid fever in early modern Italy.

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Demography of malaria

fever of typhoid in the early stages of infection, before the classic periodicity is established (if it is established), but usually without the severe gastro-intestinal symptoms of typhoid fever. Before the true aetiology of malaria was established, this similarity between P. falciparum malaria and typhoid fever led many doctors to assimilate the two in the form of a syndrome, called typhomalarial fever, whose reality is no longer accepted by modern doctors. The similarity was noted in Rome, too. Baccelli stated that the malaria of Rome frequently took the form of what he called a subcontinua tifoide.³⁸ He reckoned that Lancisi had observed the same form of the disease in the Trastevere district of Rome during the great epidemic in 1695.³⁹ This was the most dangerous type of malaria for Baccelli.

Despite its similarity to typhoid fever, Baccelli stated that it revealed the true intermittent periodicity of malaria upon careful observation. Moreover it responded to treatment with quinine.

These two features prove that the ‘subcontinuous typhoid’ fevers of Rome were P. falciparum malaria. Besides its frequent similarity to typhoid fever, P. falciparum malaria occasionally presents itself with gastro-intestinal symptoms similar to those of cholera or dysentery, as was observed in cases at Grosseto and elsewhere. In such cases at autopsy a mass of malarial parasites was observed in the blood vessels of the mucous membranes of the stomach and the small intestine, with relatively few parasites in the rest of the body.⁴⁰ Presumably this was caused by a clone targeting a chemical receptor ³⁸ Smith (1982) on the history of the idea of typhomalarial fever among doctors in the USA; Baccelli (1881: 159–60); Hirsch (1883: 235–6); North (1896: 384–5); Sambon (1901 b: 316); Marchiafava (1931: 21–2, 41).

³⁹ Baccelli (1881: 175) employed the definition of a subcontinuous fever given by Francesco Torti. Torti (1755: 190), in his famous book on the use of cinchona bark to treat malaria, defined pernicious periodic fevers (caused by P. falciparum) as follows: Porro generaliter Febris haec Periodica Pernicialis