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Howell, Stiles, and Moe (1913) believe that A. érsicus my feed on cattle more comnnnly than is generally suspec e t reasons for this assumption are not presented. This tick has been vaguely reported from Persian aninnls (Aluimov 1935) and, on the basis of a museum specimen label, from cattle in the Congo (Schwetz 19278). Hoffnnn (1930), apparently from personal infornntion, sta... ted that in Mexico A. rsicus my bite animals and man in the ab. sence of fowls. In the n1 e Provinces of India, Sen (1938) listed this species "off dog"'. Various workers have reported that they were unable to induce the fowl argas to feed on laboratory or domestic animals, or, if some blood was taken, the meal was only a partial one.

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Authentic records of A. rsicus attacking man in almost all instances stress the infrequency 0 such experiences. Reports in certain textbooks of medical entomology that the fowl tick is an important pest of man or even "'a veritable scourge ....... in the Sudan and South Africa" (I) are without the slightest foundation (see below).

In the Sudan, King (1926) reported, A. pgrsicus rarely bites nan. Several nymphs and adults in Sudan Eovernment collections are labelled "from Yemenese nan, Sualcin, 7.3-0‘), 0. Atkey". The inference is that the specimens were taken on the person. The numerous Kosti specimens already mentioned in Sudan records arouse suspicion that this species have been a pest in houses there at one time. My own inquiries in nnny parts of the Sudan and from reading a considerable number of travel, medical, a.nd natural history reports of the Sudan have failed to reveal any indication that A. Ersicus is known as a human pest anywhere in the Sudan.

In South Africa, Bedford (1934) wrote, A. Ersicus seldom attacks man. Iounsbury (l90('B ,l903B) recorded-a severe bite on a person in Graa.ff..Reinert, and stated that he had heard of two other persons who were bitten, but, especially in the former paper, he minimized the importance of A. rsicus as a pest of people, as did Behr (1899) for California. _Howard 1 09:), however, heard of a South African cart that had been stored in an old infested chicken house; "no one was able to ride in it afterwards“. In Southern Rhodesia, 1_\. persicus is pre-eminently a fowl parasite (Jack 1921). Drake-Brockman (l9l3B,l920) stated that this tick is found in or near huts in British Sonnliland but that it does not bite man there. From the United Provinces of India, Sen (1938) noted 5.

rsicus “on bed (presunnb can infest nan)‘. "This species was repo from Quetta (India where it was stated to infest houses and to bite human beings" (Warburton 1907). As stated above, Hoffman (1930), remarked that in Mexico Ersicus may bite mn and animls in the absence of fowls, but de s were not provided. In Korea, Kobayashi (1925) "examined certain specimens of Argas Esicus ....... said to have stung med‘.

Old Iranian (Persian) reports that 5. rsicus is such a pest of human beings that whole villages have hag £6 E moved, so widely quoted from Nuttall e_t _a_l (1908) who reviewed the earlier liter. ature, hardly bear contemporary repetition. The evidence in all cases is circumstantial a.nd based on hearsay. That these fables should have gained the stature of serious fact in most books of medical entomology is a reflection on methods of textbook fact. finding. One writer has even gone so far as to throw in for good measure a large part of the African continent as a scourged area. Since 1890 there has been hardly a single published eyewitness or corroborated report of Ar as rsicus biting hunnn beings that has not referred merely to isolate instances. Though some bites have been described as painful, only one or two have been shown to cause other sequelae.

Twentieth century Iran has not provided evidence to corrobo. rate the early apparent misrepresentations concerning the fowl tick. Carre (1909), in reporting on the frequency of larval at. tacks on chickens in Teheran did not mention that mm is attacked. Harold (1922) expressed the belief that Ornithodoros lahorensis Neumnn is actuall responsible for pd~tr1' Eted E A.

rsicus in Iran cf. also Harold (192017. Dr. Baltazard, Dire-5-. r 0 he Pasteur Institute in Teheran, an outstanding student of argasid ticks and of their disease relations, inform me that he knows of no troubles from A. rsicus in Iran so far as human beings are concerned. Delpy '(l9E::I§) observed large numbers of A. sicus and 0. lahorensis in and around peasant houses and stables near Persepofis In Iran fit he did not mention bites of either spe. cies. Delpy and Kaweh (1937), however, record an actual observa. tion in Iran of a laboratory person who, when washing his hands, noted a large nymphal fowl tick biting him. The bite was painless but the victim succumbed to a bout of anthrax, demonstrated to have been transmitted by the attack.

In Palestine, Nicholson (1919) and Dunlop (1920) attributed

human relapsing fever to bites of A. persicus. Their reports, were based entirely on circumstantial evi ence_Z'cf. also Balfour

(l920A,B), Woodcock (1920), MacKenzie (1920), etci7. Experimental evidence negates this probability.

Members of my staff and I on several occasions have questioned people who spend much time in heavily infested parks and houses in and near Cairo without finding anyone who acknowledged being bitten.

Apparently reliable accounts of 5. ersicus infesting human huts in which chickens are also kept, ans not infrequently biting persons, are those of Sergent and Foley (19l0,l922,l939) from Al. geria. Natives there refer to fleas and to the fowl argasid by the same name, Although the ticks are frequently associated with cases of human relapsing fever, they were proven by these observers to have a negative role in the transmission of spirochetes causing

the disease.

There are a few scattered, apparently authentic reports of A.

Eersicus biting man outside of Africa. One such, a vivid descrip. ion e anced by illustrations of the tick and of dark weals where

the human victim was bitten, has been reported from Romania by Ciurea and Stephanescou (1929). The attacks occured inexplicably in the upper stories of a new concrete apartment house and no chickens or pigeons were known to have been associated with the

buildings.

With regard to the lively account of attacks by ‘A. rsicus" on indigent persons in Chile (Porter 1928), see 5. reflexus, p. 77.

Reptile and 5mphibian Hosts

Although 5. ersicus always shows a predilection for avian blood, it will feed on toads if the skin of these animals is warmed,

according to Galli.Va1erio (l9llB). The blood is probably toxic for the ticks die afterwards.

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The record of A. ersicus from a tortoise in Iran (Michael 1899) is most probably Based on misidentification or incorrect

or incomplete specimen labelling.

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African records of A. rsicus in huts of indigenous people (inferred presence of chickens IE sane huts) are: Annecke and Quinn (1952) for South Africa, Drake..Brocknnn (1913) for Sonnli... land, Sargent and Foley (l9l9,1%2,1939) for Algeria, and Sudan records above. Iounsbury (1903B) stated that the fowl tick seldom occurs in South African houses unless chickens are kept close by.

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Among the many references to some phase or other in the life cycle of A. rsicus, sane of the nnre important are: Lounsbury (19033) f'5r ~rica, Nuttall et al (1908) for laboratory observations, Olenev (l‘IZ8A) for th§ ‘Saratov area of Russia, Roveda (19z,o,1950) for Argentina, Bodenheimer (1934) on temperature and humidity tolerance, a.nd Zuelzer (192aA,B,1921) on feeding, exci-e. tion, and life cycle. Hooker, Bishopp, and Wood (1912) contributed a detailed study of the life cycle in southern United States and reviewed earlier literature. These authors also provided data on growth and size of the fowl tick.

The life cycle in general under favorable conditions requires about four months.

larvae attach usually to the base of the host's wing. They feed there for five to ten days before dropping from the host and seeldng shelter. Nymphs and adults become satiated in from five minutes to ‘two hours and then seek a sheltered place in‘ the building, yard, or tree in which they secrete themselves. Feeding is usually done at night, sometimes in subdued light, seldom if ever in strong light.

Coxal fluid is emitted within a few minutes after engorgement is complete and often while the tick is stationary or moving about the host, but only infrequently while the mouthparts are still in. serted in the host's sldn.

Digestion is extremely slow and fowl blood may be identified by the precipitin test for at least 23 months after ingestion (Gozony, Hindle, and Ross 1911.).

The following notes are chiefly from Hooker, Bishbpp, and Wood (1912). Many more details may be found in their report.

Usually females oviposit after each meal, which may number up to six or seven in a lifetime. Under exceptional conditions, a female may require two blood meals before laying eggs. The greatest number of eggs deposited after the first few blood meals increases progressively from 195 to 61.6, but decreases after sub. sequent feedings to as few as 47 eggs following the seventh or last feeding. The average number of eggs laid after each engorgement was: first, 131; second, 159; third, 133; fourth, 110; fifth, 97; sixth, 95; seventh, 47. Eggs are laid in the adult tick's retreat.

Oviposition generally commences four to ten days after feeding, in summer sometimes as early as the third day. In winter or in the absence of males, egg laying may be delayed for weeks or months. Oviposition of moderately large batches contim1es over a six to ten day period but only three days are required for depositing a small number of eggs. In nature it appears that the fowl argas seldom engorges and oviposits more than five times, unless females com. mence feeding early in the spring.

Incubation of eggs extends over an eight to eleven day period in warm sunnner weather, but in cooler climates or seasons this period is extended to three weeks or even longer.

As stated above, larvae generally feed for from five to ten days, but they may complete engorgement in three or four days, and Rohr (1909) recorded two days. There is some indication that quiet, setting hens allow the greatest number of larvae to thrive, and that different breeds of hosts exert no influence on larval development. In NAMU-3 laboratories, Dr. Herbert S. Hulbut (unpublished) is finding that only a moderate nuber of larvae kills chickens used in his experiments, apparently not doing so by transmission of pathogenic organisms or by exsanguination. Nymphs and adults resulting from these larvae have no observable deleterious effect on their hosts. Reasons for this exceptional larval toxicity have not yet been ascertained.

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