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BECHUANALAND (Specimens from Ngamiland in Theiler collection). SOUTHWEST AFRICA (Neumann 1901. Trommsdorff 1914. Sigwart 1915. Mitscherlich 1941. Hoogstraal 1954C).

UNION OF SOUTH AFRICA (Lounsbury 1900C, in part confused with 0. savignyi. Pocock 1903. Donitz 1906,1907A,C,1910B. Greenway 1907. Howard 1907,1908. Cowdry 1925€,1926A,1927. Curson 1928. Bedford 1920,1926,1932B,1934,1936. Cooley 1934. Bedford and Graf 1934,1939. Cluver 1939,1947. Ordman 1939,1941,1943,1944A, B,1955. De Meillon 1940. Mitscherlich 1941. Collen 1943. Polakow 1944. R. du Toit 1942B,C,1947A,B. Thorp, De Meillon and Hardy 1948. Monnig 1949 statements refer largely to 0. savignyi. Annecke and Quin 1952. Annecke 1952. Davis and Burgdorfer 1954).

ISLAND GROUPS: MADAGASCAR (Lamoureux 1913A,B. Suldey 1916. Poisson 1927. Poisson and Decary 1930. Buck 1935,1948A,C,1949. Le Gall 1943. Millot 1948. Neel, Payet, and Gonnet 1949. Decary 1950. Colas-Belcour, Neel, and Vervent 1952. Hoogstraal 1953E). Although 0. moubata has not been reported from the COMORES group, Neel, Payet, and Gonnet (1949) state that relapsing fever of the apparent type borne by 0. moubata exists at Dzaoudzi.

Records from Zanzibar (Brumpt 1901,1908A) probably should be disregarded. They may refer to East Africa" in general. Accord ing to Dr. S. D. Robertson, Pathologist, Medical Department, in personal correspondence, 0. moubata does not occur in Zanzibar. It has been stated to be absent there (Aders 1913) and was not listed by Aders (1917B) in his report of insects injurious to man and stock in Zanzibar. Odd individuals of the tick may be imported in dhows from Tanganyika but these do not appear to become established on the island (Leeson 1953).

NORTH AFRICA AND ARABIA: Records from Libya are difficult to accept. Franchini (1932A,B,1933A,B,C,D,1934B,1935A) listed Tripolitania as the source of specimens. He was probably dealing with 0. savignyi, but Garibaldi (1935) accepted these reports. Zavattari (1932,1933,1934) stated that 0. moubata is absent in Libya. Though Franchini (loc. cit.) and Gaspare (1933,1934) asserted differently, their remarks are so confused as to negate their argument unless fresh specimens can be procured. One of NAMRU 3's well trained assistants has been unable to find 0. moubata in the Libyan localities from which it was reported.

Records from Egypt (Neumann 1896,1901,1911), without question erroneous, are probably based on mistaken identity of 0. savignyi, or possibly on mixed locality labels (Hoogstraal 195447. Halawani (1946) stated that although 0. moubata was supposed to be common in Egypt, he could not find Specimens in houses. Yakoub (1945) also noted its absence here.

According to Petrie (1939), the eyeless tampan is widespread in the Yemen (Arabia) (copied by American Geographical Society 1954,1955). From experience in the Yemen (Hoogstraal 1952C and ms., Girolami 1952, Mount 1953) it is questionable whether it is present there at all, to say nothing of being widely distributed.7

HOSTS

Introduction

Man is frequently attacked and is probably the chief host of 0. moubata. Warthogs and a few other wild animals that inhabit large burrows, and domestic pigs appear to be the only other fairly common hosts of this tick. Incidentally, it should be noted that frequent textbook assertions that larvae feed are incorrect (see Life Cycle below).

Most laboratory animals including chickens serve as experimental hosts. Different "strains may have different laboratory feeding habits, "burrow_haunting" populations being more difficult to induce to feed in the laboratory than those from domestic habitations (Heisch 1954C).

Human Hosts

The major portion of the literature concerning the eyeless tampan refers to its parasitism of human beings. Indication of this may be found in the section on Ecology below; specialized features of this problem will be considered in the forthcoming volume on tick-borne diseases.

Domestic Mammal Hosts

From the prevalence of records of attacks on domestic pigs in South Africa (Bedford 1936), Nyasaland (Wilson 1943,1950B),

Belgian Congo (Roubaud 1916, Roubaud and Van Saceghem 1916, Schwetz 1927A), Southern Rhodesia (Jack 1921,1931,1942), and Angola (Wellman 1906D,1907A,B), it appears that this animal often is an important host. In Southern Rhodesia, 0. moubata sometimes increases prodi giously in pigsties (Jack 1921,1931,1942). In the Zambi area of Belgian Congo, 0. moubata was abundant in pigsties and in huts of pig keepers, but relapsing fever was absent, and the tick was un known in local huts where no pigs were kept (Roubaud and Van Saceghem 1916). In Angola, Wellman (1906D,1907A) found as many in pigsties as in any other situation". In Nyasaland, Wilson (1943) stated, 0. moubata is suspected of causing mortality in pigs. Jadin (1951A) found specimens from pigsties in Ruanda Urundi infected with the causative organisms of food poisoning, Salmonella enteritidis; these ticks were able to transmit the bacteria to experimental animals, by biting, over a year later.

0. moubata has been said to cause much trouble in Southwest Africa by feeding on sheep in resting places and pastures (Mönnig 1949), but Theiler states (correspondence) that the ticks actually involved in this situation are quite likely O. savignyi.

Domestic animal corrals are frequently cited in review papers as important habitats of the eyeless tampan. I can find little con clusive substantiation for this assertion, except for domestic pigs. Wellman (1906D,1907A) was possibly the first person from the field to state that 0. moubata bites all domestic animals, but he did not mention that he had made personal observations. Careful search of corrals and comparison of incidence in these and in human habitations should make an interesting and simple research project in infested areas. One would expect that if domestic animals are attacked, it is chiefly in circunstances in which they are housed more or less like human beings in the same area.

(See also Ecology below).

Domestic Fowl Hosts

Domestic fowls in human habitations usually are considered to be important in maintaining the nymphal stage, but there is some controversy on this point (Knowles and Terry 1950, Phipps 1950). Rodhain (1919A) found avian blood in specimens from a vacant house in the Congo inhabited by chickens. Geigy and Mooser (1955) failed

to find evidence of spirochetes in domestic fowls from tampan in fested dwellings in Tanganyika, a suggestion that these ticks do not feed on fowls or do not transmit these organisms to fowls, or else that Borrelia duttonii does not survive in fowls in nature.

Along with A. persicus, Mitscherlich (1941) discussed the ravages of 0. moubata in chicken houses in the Union of South Africa and in Southwest Africa (= Deutsch Südwest Afrika). It is not, however, clearly stated that this writer actually saw eyeless tampans in these situations. His remarks give the im pression of being based on the assumption that O. moubata is an important parasite of domestic chickens.

(See also Ecology below).

Wild Mammal Hosts

See also "Wild" Habitats under Ecology below.

A wild relative of the domestic pig, the warthog, Phacohoerus aethiopicus subspp., is a normal host of 0. moubata under conditions not influenced by man. An African boy in Northern Rhodesia has been observed emerging from a warthog burrow with about thirty nymphs biting him (Lloyd 1915). During a survey of the plains south of Lake Edward in the Belgian Congo, Schwetz (1933À) dis covered that 0. moubata was abundant in warthog burrows but rare in native huts. Chorley (1943) found over forty specimens crawling on a warthog shot in Uganda. He stated (personal conversation) that all these specimens were nymphs. Heisch and Grainger (1950) found numerous specimens in widely scattered warthog burrows in Kenya and presented a theory on the relationship of wild and do mestic populations, discussed below in the section on "Wild" Habitats, under Ecology. A single specimen from a Northern Rhodesian warthog and a large lot of nymphs from a Nyasaland warthog burrow have been reported from material in the Nuttall collection (Hoogstraal 1954C). Warthogs are also hosts in the Sudan, as noted above and reported earlier (Hoogstraal 1954B). These mammals also have been noted as hosts in Mozambique (Santos Dias 1952H, 1953B).

In certain areas of Tanganyika, infestation of warthogs and other large mammals is well known in some quarters (Walton 1953). Walton described a warthog burrow in which 41 hungry later-stage nymphs and adults were found; stomach blood smears from these gave a positive reaction to pig antisera. 0. moubata was also discovered in three other warthog and porcupine burrows in foothills of the Usambara Mountains. Literally hundreds of nymphs and adults emerged from the floor and ceiling to attack Walton and a friend when they entered some of these burrows. Subsequently, specimens were found in six other burrows and in two hollow baobab trees that were used from time to time as retreats by various kinds of animals. Smaller burrows in the Usambara Mountains area, presumably belonging to the giant forest rat, Cricetomys sp., were uninfested.

More recently in Tanganyika, Geigy and Mooser (1955) examined 55 burrows of warthogs, originally dug by antbears (Orycteropus afer), and found eyeless tampans in eighteen of them. More than 1,200 tick specimens were collected from these retreats and an additional one was taken on the body of a freshly shot warthog. They also found the burrows of other kinds of mammals infested in Kenya.

In connection with Sudan specimens from warthog burrows (Hoogstraal 1954B) (see also DISTRIBUTION IN SUDAN above), it is of interest to note that these are from the "Nile sponge" region that becomes a vast lake during the rains. Just what the ticks do during these floods should be worthy of investigation.

Walton's (1953) records for porcupine (Hystrix sp.) burrows are noted above. Heisch (1954E) noted nymphs and adults in porcupine burrows in Kenya and found that they had fed on porcupine blood. Geigy and Mooser (1955), also working in Kenya, did not find ticks in a porcupine burrow that they examined but a nearby hyena shelter was heavily infested.

In South Africa (Theiler, unpublished), specimens of 0. moubata have recently been taken from burrows of aardvarks or antbears, Orycteropus afer, near Stockpoort in the Potgietersrust area. Search for ticks in the retreats of these large, almost hairless animals will undoubtedly provide further interesting data. As noted elsewhere, other workers have found eyeless tampans in burrows originally dug by antbears but later occupied by warthogs.

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