Grassi, Giovanni Battista

(b. Rovellasca, Italy, 27 March 1854; d. Rome, Italy, 4 May 1925)

entomology, parasirology.

The son of Luigi Grassi, a municipal official, and of Costanza Mazzuchelli, a peasant of unusual intelligence, Grassi was educated at Saronno. From 1872 he studied medicine at Pavia, graduating in 1878. He then went to Germany, where he worked at Heidelberg with the zoologist Otto Bütschli and the anatomist Carl Gegenbaur. There Grassi met his future wife, Maria Koenen. In 1883 he was appointed professor of zoology and comparative anatomy at Catania. In 1895 he became professor of comparative anatomy at Rome University, where he remained for the rest of his life. In 1908 he was appointed a senator of the kingdom.

As an anatomist Grassi studied the development of the vertebral column in bony fishes (1883), and as a physician he studied endemic goiter (1903–1917). Some of his more elegant studies were in pure entomology: on bees (1877–1884); on myriapods (1886–1889); and his monumental work on termites (1885–1893). For the latter work he was awarded a Darwin Gold Medal. He also studied the Chetognates (1881, 1883) and the reproduction of eels (1910–1919), and in 1885 he described a new species of spider (Koenenia mirabilis), naming it for his wife. Nevertheless, he is remembered today essentially for his studies in parasitology and in practical and applied entomology.

In 1876 in his native Rovellasca Grassi investigated the high mortality of cats and discovered in their bowels large numbers of Dochmius balsami, strongly hematophagous little worms very like Anchylostoma. In 1878, while still a student at the medical clinic of the University of Pavia and working under Francesco Orsi, he discovered anchylostomiasis in Italy. He made the diagnosis as a result of finding Anchylostoma eggs in feces.

Grassi developed a wide knowledge of helminthology, writing first on Anguillula intestinalis (or Rhabdonema strongyloides) in patients with marshy cachexia (1878–1887). He also studied Filaria (1887-1901), Trichocephalus dispar (1887), and Bilharzia (1888); but he was concerned particularly with the tapeworm. Grassi was the first to demonstrate that Taenia nana is able to go through its entire life cycle in one animal, without the need of an intermediate host, a fact that had long been denied. He was also the first to show that the flea Pulex serraticeps is the intermediate host of larvae of Taenia Cucuerina ellptica. Thus he wrote that the swallowing of infected fleas (for example, with milk) might be the reason for Taenia. in children.

Grassi also made important studies on the parastic and pathogenic protozoa (1879–1888). Of great practical importance were his studies on the fly (1879-1884): it could swallow, and expel still alive, the spores of Botrytis and Oidium, the eggs of Taenia or Trichocephalus, and even bacteria, particularly the cholera bacillus. Grassi then began a campaign to eradicate flies. Grassi made his first observations on malaria in 1890, when in collaboration with Raimondo Feletti he discovered Plasmodium vivax. (In 1889 Ettore Marchiafava and Angelo Celli had discovered Plasmodium falciparum, the deadliest form of the malarial parasite.) This confirmed the validity of Camillo Golgi’s assertions (1885–1889) that the differences in the period (three or four days) and the severity of various malarial fevers arise because of different species of the malarial parasite. Also in collaboration with Feletti, Grassi worked on malaria in 1891 and 1892 and discovered the malaria parasite of birds (Proteosoma praecox, very like Plasmodium aiuax). In 1891 he performed the first inoculation of malaria parasites from one bird into another. But all of Grassi’s decisive investigations on the transmission of malaria in man were made between 15 July and 30 November 1898 and reported to the Accademia dei Lincei (see Rendiconti, meeting of 22 December 1898).

In 1894 Amico Bignami, in collaboration with Giuseppe Bastianelli, produced a typical malarial fever paroxysm in a healthy man by intradermically injecting a minute drop of blood from a malaria patient. But in 1896 all his attempts to produce malaria in man by the bite of mosquitoes failed. Nevertheless, human malaria from inoculation by mosquito bite—affirmed in 1896 by Bignami and by the English pathologist Patrick Manson in his lectures to the Royal College of Physicians of London—was accepted as most probable. Grassi was struck by the fact that there are always mosquitoes wherever malaria is found, which had already been observed in 1716 by the Italian physician Giovanni Maria Lancisi. Grassi, however, also noted that where mosquitoes abound, malaria is not necessarily present. After deducing that only a particular species of mosquito could transmit malaria to man, it became a question of identifying the species. In August 1898 Grassi discovered that the agent transmitting malaria to man is the female Anopheles mosquito, most frequently of the species A. claviger.

In November 1898, with the help of Bignami and Bastianelli, Grassi produced experimentally in a healthy man a typical malarial paroxysm of malignant tertian fever, resulting from bites of Anopheles mosquitoes. He then demonstrated that all anophelines are capable of becoming the hosts of human malaria parasites during sporogony. In consequence of these demonstrations, Grassi launched a great antimalaria campaign, emphasizing human protection through window screens, prophylaxis with quinine, and the destruction of Anopheles with Gambusia, which devours its larvae. Above all, Grassi recommended extensive distribution of quinine to all persons in malarial districts, because quinine kills the parasites of malaria and thereby prevents the infection of new anophelines. In 1899 he demonstrated that Anopheles is born uninfected and becomes able to transmit malaria only after biting an infected human. Grassi understood the importance of continuous suppressive treatment of malaria with quinine, so as to prevent the occurrence of the asexual blood stages in both uninfected and chronically infected persons.

That Grassi discovered the pathogenic activity of anophelines and, in consequence, is responsible for the victory over human malaria, is undeniable. But the English surgeon Ronald Ross claimed priority and the 1902 Nobel Prize for physiology or medicine was awarded to him; even today this decision is widely accepted. Indeed it was Grassi who first demonstrated the sporogonic cycle of the human malaria parasite (its schizogonic cycle had already been described in 1889 by Golgi). Although unappreciated at the time. Grassi also identified the true agent transmitting malaria in man. Today it is well accepted, in a zoological sense, that while man is the intermediate, the Anopheles mosquito is the definitive host of malaria parasites.

Ross made some very important observations on malaria in birds, working from 1896 to 1898 under Manson. In the summer of 1898 the achieved the transmission of experimental malaria in birds by the bite of mosquitoes. He also demonstrated the entire life cycle of Proteosoma, the malaria parasite of birds, which concludes as a sporogonic cycle, resulting in the formation of sporozoites that accumulate in the salivary glands of a mosquito. Thus, when the mosquito bites, it inoculates a bird with malaria parasites. Ross also stated that malaria is transmitted in man by the bite of mosquitoes but did not demonstrate this. In addition, in 1898 he did not know of the genus Anopheles, nor was he convinced of the mosquito’s exclusive importance in transmitting malaria. In 1903 Grassi published his precisely documented vindication, but Ross never acknowledged priority.

Grassi turned to a new field of research—the study of the phylloxera of grapes—which he pursued for several years. On the strength of his first notes. La questione fillosserica in Italia (1904), the Italian Ministry of Agriculture requested him to do an exhaustive study of this subject. In 1912 he collected his own observations and those of his collaborators in a precise and monumental analysis of the morphology and biology of the Italian and other European genera of phylloxera. Thus it was possible to begin the fight against this agricultural pest.

Grassi was an extremely private person, and an affectionate husband and father. His forty-two years of teaching and research testify to his deep devotion to science. But his greatest source of pride was that he opened the way to the eradication of malaria. Thus he chose to be buried in the cemetery of Fiumicino, an area that his personal and persevering initiative had rid of the disease.

BIBLIOGRAPHY

Grassi’s scientific production was enormous. Alone he wrote more than 250 papers, collaborating on another 100 with his students. For a full listing of his works, see A. Pazzini, “Giovanni Battista Grassi,” in Rivista di biologia, 19 (1935), 1–46.

For information on Grassi or his work, see A. Corradetti, “L’opera protozoologica di Battista Grassi alla luce degli odierni sviluppi della scienza,” in Riuista di parassitologia, 15 (1954), 190–199; A. Corti, “Battista Grassi e la trasmissione della malaria,” in Studia ghisleriana, 1 (1961); C. Golgi, “Sul ciclo evolutivo dei parassiti malarici nella febbre terzana,” in Archiuio per le scienze mediche, 13 (1889), 173–196; and C. Jucci, Nel centenario della nascita di Battista Grassi (Milan, 1954).

See also S. Piccini, “Nel centenario della nascita di Battista Grassi,” in Atti del XIV congresso internazionale di Storia delta medicina (Rome-Salerno, Sept. 1954); F. Silvestri, “Commemorazione del Socio Nazionale Giovanni Battista Grassi,” in Atti dell’Accademia nazionale dei Lincei, memorie (1926); and C. Tumiati, “Giovanni Battista Grassi,” in Vite singolari di grandi medici dell’800 (Florence, 1952), see esp. pp. 125–135 for the clearest assessment of Grassi’s priority over Ross.

Pietro Franceschini