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LEISHMANIASIS OF THE NEW WORLD: TAXONOMIC PROBLEMS   R . Lainson&J. J.  J. Shaw 1. Visceral Leishmaniasi Leishmaniasiss The existence of visceral leishmaniasis in the Americas was first noted by Migone (1913) in Paraguay and has since been recorded in Bolivia, Brazil, Colombia, Guatemala, El Salvador and Mexico. In Brazil, where where most of the pi pioneer oneer epidemiological studies were made, the dog and wild foxes have proved to be impo rtant reservoirs of infection infection (Deane & Deane, 1954). The major sandfly vector  is  generallyy cons idered  generall to  beLutzomyia longipalpis, at least in the highly highly endemic are as

LEISHMANIASIS OF THE NEW NEW WORLD : TAXONOMIC PROBLEMS R. LAINSON Ph.D. D.Sc. J. J. SHAW D.A.P.E. Ph.D.

This paper concentrates on the taxonomic problems of New Wo rld leishmaniasis, as we hav e recently extens extensivel ivelyy revie reviewed wed its epidemiology (Lainson & Shaw, 1971). Because of past emphasis on clinical appearances, the New World leishmaniae have been largely classified on this basis and a bewildering array of terms has resulted, often applied to the same disease state and very often caused by the same parasite—Chiclero's ulcer, Bay sore, pian bois, bush yaws,   framb oesiform cutaneous lei leishmaniasi shmaniasis, s, uta, sim ple or   diss em inate d cutaneous leishmani leishmaniasis, asis, espundi espundia, a, mucocutaneous lei leishmaniasi shmaniasis, s, verru cos e , vegetative or   no du la r cutaneous lei leishmanias shmaniasis, is, and diffuse cutaneous leishmaniasis, to name but a few. If leishmaniasis were restricted to man such a classification might be excused, but the various forms of the New World disease are zoonoses , stemming from diffe different rent wild or domestic anim als; man is normall normallyy to be regarded only as an inci incidenta dentall host and plays no important role in the maintenance of the paras ites in natu re. Finally, whi while le a giv given en  Leishmania   m ay prod uce an over-all similar cli clinical nical picture in man, individuals individuals may react differently to the same parasite and the appearance

of north-east Brazil Brazil. . This insect insect is inpart partiall ially y ad apted peridomestic habitats and is prevalent and around the to houses, feeds readily on dogs, foxes and man, and has several times been found infected in nature. However, it was not in the arid area s that the first Brazi Brazilian lian cases of visceral leishmaniasis were discovered, but at the mouth of the Amazon, in the dense, humid forested areas of Para (Chagas, Marques da Cunha, de Oliveira Castro, Castro Ferreira & Romafia, 1937; Chagas, Marques da Cunha, Castro Ferreira, Deane, Deane, Guimaraes, Guimaraes, von Paumgartten & Sa, 1938). 1938). Surprisingly enough,   Lu .  longipalpis   was also identified here as the local vector, found in the thatched huts built on the terra firma along the river and coastal margins and in forest forest clearin clearings. gs. It was assumed that som e wild wild animal reservoir must exist, but not until recently were infections found in foxes caught near Belem (Lainson, Shaw & Lins, 1969;  Lainson & Shaw, 1971). 1971). There remains considerable doubt as to the true epidemiol epidemiology ogy of tthis his sylvatic kalaaz ar in north Brazil Brazil.. Thus , recent search searches es for Lu .  longipalpis in the endemic areas and where the infect infected ed fox foxes es were caught have produced no further evidence of thi thiss sandfl sandfly. y. Althou gh readily colonized in drier conditions, L u.  u.  longipalpis   does not do well in laboratories with high temperature and humidity. Perhaps Chagas and his col colleagu leagues es were dealin dealingg with ano ther, closely related, species of sandfly. As regards the parasite, most authorities have considered it to be identical with   Leishmania donovani  (which causes kala-a zar in Ind ia). This vi view ew arose largel largelyy fro from m the clinical picture in man, and there has been litt little le dire direct ct comparison of the actual parasites from the various parts of the two hemispheres in which which th they ey occur. Presumably, however however,, there is no reason why different leishmaniae might not cause a similar visceral disease in man, in the same way that others cause skin disease. Nicolle (1908) differentiated between   Leishmania   infantum

of the disease may vary greatly at different stages of the infection. It has proved far from easy, however, to classify the leishma niae on a sounder, zoological zoological basis. In the vert vertebrate ebrate host they all assume the simplest form of the Trypanosomatidae, the amastigote (Leishman-Donovan body), which shows a strikingly similar morphology among all the leishmaniae infecting man and most of those infecting other qnima k. In the invertebrat invertebratee host, too, the morphology morphology of the promastigote (leptomonad) j s  generally regarded as indistinguishable among the different species of  Leishmania.  O ur lack of knowledge on many aspects of host-vector relationships and of a simple laboratory test to differentiate the leishma niae h as stood in the way of progress. These di diffi fficul culti ties es must be overcome, for information on the biology, morphology, biochemistry, and immunology of   Leishmania  remain  remain prerequisites to any sensible classificat classification. ion. Fortunately, in recent years, there has been new interest in these aspects.

an d   L. donovani,  whichThis cause M editerranean a nd Indian kala-azar, respectively. opinion was not unanimously accepted, although Adler (19 (1940) 40) and A dler & Theo dor (19 (1957) 57) gave it convincing epidemiological and experimental support. If, as seems desirable,  L. infantum  is accepted as a valid species, the taxonomy of the parasite causing New World visceral leishmaniasis mus t be reconsidered. Ma ny have suggested that the American disease was imported during the Spanish and Portuguese conquests and, if so,  L. infantum would be a more suitable name than  L. donovani, on the basis of epidemiol epidemiologica ogicall evidence alone. Like Adler & Theod or (1957), however, we regard American visceral leishmaniasis as an indi indigenous genous disease, st stemming emming from from a wil wildd animal s ource. On grounds of geographical isolation alone, there would seem seem to be even more reason for separating of offf the parasite of American visc visceral eral lei leishmaniasis shmaniasis than there is fo forr the distinction between   L. donovani an d  L. infantum.  We therefore intend to readopt the use of the two names   L. infantum

Th e   Wellcome  P arasitology arasitology Unit Belim,  Pard,  Brazil

1 2 3 4 5 6 7

Visceral leishmaniasis Present classi classificat fication ion Ro den t lleishmaniasis eishmaniasis in Brazil and its relationship to the disease in man Prop osed re-cl re-classifi assification cation of parasites The  Leishmania mexicana  complex The  Leishmania braziliensis  complex Conclusions References

 

Br. med. Bull.  1972

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LEISHMANIASIS OF THE NEW WORLD: TAXONOMIC PROBLEMS   R. Lainson R. Lainson   &J. J. Shaw (Nicolle, 190 1908) 8) and  Leishmania chagasi  (Marques da Cunha & Chagas, 1937) for the parasites of Mediterranean and New World visceral leishmaniasis, respectively. 2.   Presen t Classifi Classification cation

It is gen general erally ly agreed that the leishmaniae causing cutaneous and mucocutaneous leishmaniasis in the Americas are indigenous and do not represent strains o r subspecies subspecies of imported Leishmania tropica   (Noguchi, 1924; Adler, & Theodo r, 1957; Lainson & Shaw, 1971). 1971). The 1940; disease diseaseAdler extends from the Yucatan in the north to Argentina in the south and, early on, there was a tendency to regard all the different clinical clin ical manifestat manifestations ions as due t o a sing single le parasite, Leishmania braziliensis  (Vianna, 1911). As later stressed by Adler (1962), however, howev er, . . . use of one name  L .  brasiliensis   . . .  has been an important obstacle obstacle in the path of research. The first attempt to clear the picture was made by Biagi (1953), who referred to the causative organism of Chiclero's ulcer in Mexico, Guatemala and British Honduras as   L. tropica mexicana.   This trinomial system was followed by Floch (19 (1954) 54),, who ad ded  L. tropica  L.  tropica brasiliensis  for the parasite of mucocutaneous leishmaniasis in Brazil and   L. tropica guyanensis for tha t causing uta in Peru, pian bois in the Guyanas and cutaneous leishmaniasis in Costa Rica and Panam a. Pess6a (1 (1961) 961),, on the other hand, considered all these parasites a  subspecies of L.  braziliensis  and differ differentiat entiated ed  as s

between  L.  braziliensis guyanensis braziliensis guyanensis  a n d L .  brazili braziliensisperuviana. ensisperuviana. He included the name of   L.  L.   braziliensis  pifanoi,  given to the parasite isolat isolated ed from Venezuelan diffuse cutaneous leishmaniasis leishmaniasis by M edina  Romero (1959). Finally, Garnham (1962) (1962) gave the parasite of Chic lero's ulc er spe speci cifi ficc rank as  Leishmania   mexicana. Adler   (1963,  and personal communication in Lainson & Shaw, 1966) and Lainson & Shaw (1966) produced serological and immunological evidence to differentiate   L. tropica, L. mexicana, L. braziliensis L.  braziliensis  (mucocutaneous case from Brazil) and a strain of   Leishmania  (isol (isolated ated from ma n in Panama); while Schneider & Hertig (1966) separated off Panamanian strains from both  L  L..  mexicana  a  a nd L.  L.    braziliensis peruviana  by immunodiffusion techniq ues. 3.   Rodent Leishmaniasis in Brazil and its Relati Relationship onship to the Disease in Man

In recent publications we have discussed the prevalence of rodent leishmaniasis in Brazil and its transmission by the sandfly  Lutzomyia flaviscutellata  (Lainson & Shaw, 1968; Shaw & Lainson, 1968). At first it was tempting to regard this vast reservoir reservoir of infecti infection on as the m ajor source of cutaneous and mucocutaneous leishmaniasis found so abundantly in the same regions (Nery-Guimaraes, Azevedo & Damascene 1966). 1966 ). Observations over th e last five years, however, have produced two important facts: firstly that   Lu. flaviscutellata only rarely rarely bites man, an d secondly that the pa rasites isolat isolated ed from from the rodents are in most cases vast vastly ly di diff ffere erent nt from those isolated isolat ed from from m an. Fro m their behaviour iinn hamsters and in blood-agar media we concluded that we were dealing with two distinct leishmaniae which were provisionally referred to as the fast-growing and slow-growing parasi parasites tes (Lainson & Shaw, 1969, 1970). The fa st parasite, from man or roden ts, behave behavess like L.   mexicana  when inoculated into the skin of hamsters and

Vol. 28  No . 1

mice. It produces large, tumour-like histiocytomata containing enormous numbers of amastigotes, without any very marked host cellular response; the parasite grows luxuriantly and is easily maintained in most blood-agar media (e.g. NNN, the culture medium of Novy-Nicolle-McNeal). The sl ow parasite, on the other hand, grows very slowly slowly in the hamster skin, producing only a small fleshy swelling characterized by marked cellular response to scanty numbers of organisms. In classifying isolations of  Leishmania these two groups, it soon our became apparent that the   into slow-growing parasite was that responsible for the great majority of infections in man; this included all of 14 cases of mucocutaneous leishmaniasis studied, and 50 out of 57 cases of uncomplicated skin lesions. lesions. Only seve sevenn persons provided the fast-growing fast-growing parasite. Of these, four were cases of 1 anergid   diffuse cutaneous leishmaniasi leishmaniasiss and three had single ulcerative lesions. Among the wild animals, isolations were almost exclusively of the fastfast-growing growing parasite. Thus , rodents an d opossum s have yielded 39 infections with this   Leishmania and only a single exam ple of the  slow-growi  slow-g rowing ng organism ; a slow-gr slow-growing, owing, Leishmania-Mk parasite has been isolated from the viscera of sloths   (Choeloepus didactylus)   in Para State, Brazil, but has yet to be identified (R. Lainson and J. J. Shaw, unpublished observations). There is little doubt that we can classify the slow-growing Leishmania, here in Brazil, with the species  L. braziliensis. In man it gives rise to relatively severe, long-lasting lesions, frequently associated with later involvement and destruction of the nasopharyngeal tissues. The resemblance of the fastgrowingg parasite t o  L.  mexicana growin   has been mentioned (Lainson & Shaw, 1968), and at first we were inclined to refer to it simplyy by this name . We were deterred fr simpl from om doing this, however, when considering considering the wide geographical sepa ration, different hosts, different vectors   (Lu. flaviscutellata  an d Lutzomyia olmeca),  and the absence of any entity comparable with Chiclero's ear in Brazil. Brazil. These, and some other difdifferences in the behaviour of the parasites in laboratory nnimnk 1  suggest  suggested ed to us that com plete synonymy would be an over-simplification. 4.   Proposed Re-Classif Re-Classificat ication ion ooff Par asites

Clearly, there is emerging more and more evidence of an evolving complex evolving complex of leish leishmaniae maniae in th e New World for which our present system of taxonomy taxonomy is inadequate. As well as the existing parasites known to infect man, we now have to deal with such o ddit ies as Leishmania   enriettii,  the leishmaniae of rodents, sloths, porcupines and other forest animals, and the  Leishmania   or o r Leishmania-Uke  parasites isolated from wild-caught wildcaught sand sandfli flies. es. Finall Finally, y, workers in Panam a have demonstrated different serotypes among the   Leishmania isolated from m an in that country (Schneider  Hertig , 1966) 1966),, and that a  Leishmania   isolated from the skin of porcupines is  isolated unrelated to any known human strain (Schneid (Schneider, er, 1968). An extension of the trinomial system as used by Pessfia (1961) (1961) would do m uch to ease the situation, and en able a m ore ready naming of  Leishmania   parasites which would otherwise  parasites sink into obscurity under such descriptions as  "Leishmania sp. ,   fast-growing  Leishmania   of rodents or "Leishmania  

N ot   qoh mneig k —ED

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LEISHMANIASIS  OF THE NEW WO RLD: TAXONOMIC PROBLEMS PROBLEMS  R. Lainson   Lainson J.  J.  Shaw brazilicnsis  sensu la lato to . We have accordingly accordingly utilized utilized two major groups, which w we e w will ill refer refer tto o as the  L. mexicana and L.   braziliensis complexes, containing what we believ believe e t o be subspecies subspec ies and relat related ed species of these organism organisms. s. Broadly speaking, these two groups coincide respectively with what we have previously referred to as the fastfast-growin growing g and   slow-growing slow-growi ng parasites.

However, some leishmaniae leish maniae either deserve separate spe specific cific rank ran k or do not fit clearly into the present grouping. grouping. Thus, the morphology and host specificity of  L. enriettii clearly marks this peculiar organism off from all other known leishmaniae, although its behaviour iin n the guinea-pig guinea-pig and in NNN culture suggests links with the  L. mexicana complex, with which we now place it. Uta, in Peru, is the only form of New World cutaneous leishmaniasis unassociated with forest and which has apparently no wild animal reservoir. It is isolat isolated ed on the dry, barren slopes of the Peruvian Andes, where the only known reservoir is the domestic dog. From the little availab available le information on its behaviour in hamsters and NNN culture, it seems best to include the parasite, as  as  Leishmania peruviana, in the L.  braziliensis  complex.

mexicana Complex The e Leishmania mexicana 5.   Th

and d  cause extensive destruction  of the  pinna;  no  nasochronic  an  off anergid pharyngeal involvement; has produced one recorded case  o diffusee cutaneous leishmaniasis diffus leishmaniasis from Mexico.  L.  braziliensis (Neryii.   L.  mexicana amazonensis  nov.  s.sp. — Guimaraes  & da  Costa, 1966). Reservoir hosts: small forest rodents, more rarely opossums— Oryiomys capito, Oryzomys macconnelli, Oryzomys laticeps, Nectomys squamipes, Neacomys spinosus  (Cricetidae); Proechimys guyannensis  (Echimyidae); M armosa murina, Marmosa fuscata fuscata  an d

Marmosa m ills ills   (MarsupiaJia: Didelphidae). Sandfly Sandf ly ve ctor:   Lu. flaviscutellata. Geographical area: Amazon basin, into Mato Grosso State, Brazil, and Trinidad, probably extends into other South American countries where the vector occurs. Behaviour in ham ster: rapid prod uction of histiocytomata histiocytomata in skin of extremities (but grows less readily readily  in hamster flank or  other furred   mexicana m exicana) parts than does  L. mexicana m exicana);; metastasizes  to extremities after   a few months. Behaviour  in NNN med ia: grows luxuriantly  and is  easily maintained. Clinical features: rarely infects   man,  owing  to  disinclination  of vector   to  bite  him;  single  or  limited cutaneous lesions, usually with abundant parasites;   no predeliction  for ear  tissue  as in  L. mexicana mexicana,  and no  nasopharyngeal involvement; responfor  occasional cases  of  anergid diffu se cutaneous leishsible   for (in n  Par& State, Brazil); recorded  in rodents  in Trinidad, maniasis  (i but the disease  is unknown in man there.

Leishmaniae of this complex are principally cutaneous parasites of small forest rodents, more rarely opossums, producing inconspicuous dermal nodules, plaques or ulcers on the cooler extremities, predominantly the tail, although they may be isolated from apparently normal skin. Transm Transmission ission among natural hosts apparently is limited to a few species of the intermedia the intermedia group of sandf sandflies lies (Theodor, 1965 1965), ), in particular Lu .   olmeca  and  Lu. flaviscutellata.  Prolific development of promastigotes occurs throughout the mid-gut and fore-gut, but excluding the hind-gut triangl triangle. e. Parasites mu multiply ltiply rapid rapidly ly in hamster skin, producing histiocytomata which are packed with amastigotes and show a poor host-cell response; metastatic spread to the extremities commonly occurs in the hamster. Growth is luxuriant and maintenance easy in NNN and other blood-agar blood-a gar media. Cutane Cutaneous ous lesions lesions in man are usually of a mild nature and there is no nasopharyngeal involvement.

Classification i.   L.  mexicana mexicana  (Biagi, 1953) = L.  tropica mexicana (Biagi, 1953);  L.  braziliensis mexicana  (Pessoa, 1961); L. mexicana   mexicana (Garnham, 1962). desmarestianus nus Reservoir hosts: small forest rodents— Heteromys desmarestia   Nyctomys sumichrasti, Ototylomys phyllotls, and (Heteromyidae) • Sigmodon hispiaus  (Cricetidae).  olmeca. Sandfly vector:  Lu. olmeca. Geographical area: Mexico (Yucatan), Guatemala   and  British Honduras, possibly extending into other parts   of Central   Central America. Behaviour in ham ster: rapid production of histiocyt histiocytomata omata at point of inoculation into any part   of skin, with spread  to extremiti  extremities es within few w months. a   fe Behaviour   in NNN media: grows luxuri luxuriantly antly  and is  easily maintained. Clinical features: causative agent   of  Chiclero's  ear or Bay sore; in immunologically competent persons usually   a  relatively mild infection with   a  single cutaneous lesion which  is  self-healing;

ear lesions, however, form   up to 40 % of  cases,  arc pe rsistently rsistently

  L.  L. brasiliensispifanoi iii. pifanoi i —  brasiliensispifanoi  (Medina   Romero, L.  diffusapifano   L.  pifanoi  (Medina  & 1959);  mexicana   (Adler, 1962);   Romero, 1962). Reservoir hosts: probably small forest rodents— rodents— Zygodontomys microtinus  (Cricetidae)  and  Proechimys guyannensis  found with tail lesions. Sandfly vector: unknown. Geographical area: Venezuela. Behaviour in hamster: rapidly produces large histiocytomata  at site of inoculation   in skin, with metastases  to other extremities after  a few months. Behaviour   in NNN me dia: grows luxuriantly  and is  maintained easily. Clinical features: so  fa  farr only known from cases of anergid diffuse cutaneous leishmaniasis.

iv.   L.  enriettii (Muniz  &  Medina, 1948);  the only species readily distinguished from distinguished from all others by the m orphology  of the amastigotes, which are unusually large. Natural host: unknown; discovered   in  laboratory guinea-pi^s (Cavia porcelhts); (Cavia  porcelhts);  but will   will not infect  the wil  wildd B razilian guinea-pig (Cavla   apered). (Cavla Sandfly vector: unknown;   has produced heavy experimental infection in   Lutzomyia gomezi,  with  no  involvement  of the  hind-gut triangle. Geographical area: Curitiba, ParanA State, Brazil. Behaviour   in hamster:  not infective,   infective,  or  produces only  a fleeting infection. Behaviour  in  guinea-pig: produces marked nodules  and ulcers in the extremities with metastases; lesions contain abundant parasites. Behaviour in in N NN media: grows well well  and easil  easilyy maintained . 6.

The Leishmania braziliensis Complex The Leishmania

Wild anima animall hosts are poorly known. Infections Infections arc occasionally found in forest roden rodents ts (Panama and Brazil) and in procyonids and marmosets (Panama): Leishmania-

Br . med.  Bull.  1972

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LEISHMANIASIS OF THE NEW WORLD: TAXONOMIC PROBLEMS   R . Lainson   &J. J. Shaw Behaviour in NNN media: very difficult to culture; initial growth weak, usually lost on subsequent passage. Clinical features: causative agent of pian bois; may occur as single lesion but very commonly spreads to give many crater-like ulcers all over body; metastases often seen as nodules along lymphatics; scanty numbers of parasites; the rare cases of nasopharyngeal involvement recorded are almost certainly due to geographical overlap of  L .  braziliensis  braziliensis.

like organisms in the skin and viscera of sloths (Panama and Brazil) are of a more doubtful nature. Parasites are limited to discrete but inconspicuous skin lesions, or to apparently norm al ski skin. n. The parasites are transmitted among wild animals and to man by a variety of sandflies of the   intermedia  an d  Psychodopygus  groups; parasites develop throughout mid-gut, fore-gut, and in the hind-gut triangle. They grow slo slowly wly iinn the ski skinn of ham ster nose or foot, producing a small fleshy swelling which usually

iii.   L. braziliensis panamensis  nov. s.sp. = L .  brasiliensis guyanensis (Floch, 1954). 1954). Reservoir hosts: forest rodents— Proechimys semispinosus   an d HoplomysgymnurusCEchimyidae;); the marmoset,  marmoset, Saguinusgeoffr Saguinusgeoffroyi; oyi; otosflavus; avus; the olingo,  the kinkajou, P otosfl olingo, Bassaricyongabbii Bassaricyongabbii;; the sloths, Choeloepus hoffmanni   an d  Brady pus infuscatus infuscatus;;  uncertain if all represent infection with the same parasite, although the parasite of Proechimys of  Proechimys   has produced typical lesions in volunteers. Sandfly vectors: based on infection of hamsters with promastigotes from dissected sandflies:  Lutzomyia trapidoi; L utzomyia ylephiletrix; Lu. gomezi; Lutzomyia  panamensis. Geographical area: Panama, possibly extending into Central America in the north, or Colombia in the south. Behaviour in hamster: slow development of small fleshy swelling at point of inoculation (nose or foot); moderate numbers of amastigotes in lesions, and considerable tissue response; no metastatic spread in skin. Behaviour in NNN media: grows reasonably well and relatively easy to maintain. Clinical features: single or limited number of shallow, crater-like

does notrate ulcerate. numbar ersresponse ooff amastigotes areThere scanty to mode and the The host cellul cellular is mark ed. is no metastatic metastatic spread. Growth in blood-agar m edia iiss poor to moder ate and oft often en impossible to maintain. With the exception of   L. L.    braziliensis   guyanensis, serological differentiation has been made between the different members of the   L. braziliensis  complex, and between these and parasites of the L.   mexicana   complex. In m an, singl singlee or multiple skin lesions lesions are often often very ext extensive ensive and disfiguri disfiguring. ng. Nasop harynge al involvement has occurred with at least one subspecies. Classification

i.   L.  braziliensis braziliensis braziliensis  (Vianna,  (Vianna, 1911 )-Z. )-Z. wrightii  wrightii  (Pedroso & da Silva, 1910);   L. tropica  var.  americana (Laver (Laveran an & NattanLarrier, 1912);   L. americana var.  flagellata  (Escomel, 1913);  L. tropica   var.  brasiliensis (Pif (Pifano ano C , 1940) 1940);;  L. tropica brasiliensis (Floch, 1954). Reservoir hosts: poorly known; based on isolation and behaviour in hamster and NNN media, a single infection is recorded in the rodent   Oryzomys concolor  fro from m Ma to Grosso State, Brazil; reports also exist of infections in the paca   (Cuniculus   paca),  a n agouti  (Dasyprocta azarae)  and another rodent,  Kannabateomys amblyonynx,   but with no observations on the parasites' behaviour in hamsters or NNN culture. Sandfly vectors: (a) based on infections in hamsters, and behaviour in NNN culture, of promastigotes found in sandflies from endemic areas of north Brazil:   Lutzomyia paraensis;  and two diff different, erent, hitherto undescribed species of the   Psychodopygus  group (J. J. Shaw and R. Lainson, unpublished unpublished observations); (b) based on microscopic evidence, only, of promastigotes in dissected sandflies in south Brazil and Venezuela:   Lutzomyia migonei; Lutzomyia whitman ; Lutzomyia anduzei. Geographical area: typically Brazil; also in adjacent forested areas, east of the Andes—in Peru, Ecuador, Bolivia, Venezuela, Paraguay and Colombia. Behaviour in hamster: small, slowly growing swelling at point of inoculation in nose or foot; usually non-ulcerative, with marked

lesions with tendency to spread as nodules lymphatics; nasopharyngeal involvement rarely described andalong possibly due to a bite on the nose rathe r than to meta static spread. Immunodiffusion tests indicate serologjcally different strains within the subspecies.  L .  brasiliensis   guyanensis (Floch, iv.   L.  peruviana   (Velez, 1913) — 1913) — 1954);  L.  braziliensi braziliensiss peruviana   (Pessfla, 1961). Reservoir host: the domestic dog; sm all nodules o r ulcers of skin, in particular of the nose and lips; often no apparent lesions and parasites scattered scattered through areas of apparently normal skin. Sandfly vectors: uncertain;   Lutzomyia verrucarum  and  Lutzomyia peruensis strongl stronglyy suspected. Geographical area: Pe ru; o n western western slopes of the Andes, up to an altitude of nearly 3000 metres; the only known form of New World cutaneous leishmaniasis unassociated with forested areas. Behaviour in hamster: surprisingly little information; but presumably infections are of mild nature or difficult to maintain, judging from the non-availability of this parasite in the laboratory; the few existing NNN cultures appear to have lost their infectivity

hostmetastatic no cellular response cellular spread inand skin. containing scanty scanty numbers of parasites; Behaviour in N N N m edia: moderate to poor g rowth; often diff diffic icul ultt to maintain. Clinical features: most destructive form of cutaneous leishmaniasis; lesions single single or ffew ew in num ber, b ut frequent frequently ly very large, persistent and disfiguring; violent tissue reaction, usually with very few parasites; metastases to nasopharyngeal tissues a common sequel (espundia).

for hamsters. Behaviour in NNN media: presumably growth and maintenance offer few problems as this parasite has been used to produce antibody for serological tests and is maintained in culture in some Leishmania   reference centres. Clinical features: causative agent of uta; in immunologically competent individuals produces single or limited lesions which are self-healing; no nasopharyngeal involvement.

ii.  ii.   L. braziliensis guyanensis  (Floc h, 1954) -  L. brasiliensis  (Floch & Sureau, 1953);  L.  tropica guyanensis  (Floch, 1954). Reservoir host: unknown. Sandfly vector: based on demonstration of promastigotes in dissected sandflies in endemic areas:  L u.  anduzei   in Surinam. Geographical area: Guyana, French Guyana, Surinam; certainly extending extendi ng into north Brazil iinn the Territories Territories of Amapa and Roraim a, and the States of Para and Am azonas; probably into east Venezuela. Venezuela. Behaviour in hamster: slow development of small, fleshy swelling

7

Garn h am (1 9 6 6 ), i n d i scu ssi n g p ro b l em s i n t h e t ax o n o m y o f t h e m al ari a p arasi t es, wro t e: A large body of opinion, although recognizing the need for reclassification, has advised delay in order to collect more data. It seems . . . that this attitude can be maintained too long . . . it is probably better to possess a list of names which can be sunk when proof of synonymy is forthcoming than to struggle with circumlocutions lithe ke non-committal the long-te rm  "Plasmodium relapse form sof or m ake do with like p .  P. vhax"

at of inoculation in nose or foot: numbers of inparasites andsite marked host cellular response; no scanty metastatic spread skin. 7

Vol. 28 N o. 1

Conclusions

 o  w n  o  a   e    r   o m    t   t   p  : 

m  .  o x  o r   o  u n r   a   s   .  o r   g    a   t  n  v  e  r   s   t   y  o    a 

 o r  n  a   ,  a  n

r   a  n  c   s   c   o  o n  e  r   u  a  r   y  , 1

 

LEISHMANIASIS  OF THE NEW WO RLD: TAXONOMIC PROBLEMS PROBLEMS  R. Lainson  Lainson   &J. J.  Shaw These sentiments apply equally well in considering the leishmaniae, which have suffer suffered ed too long l ong from such terms as   the New World variety of  L. donovani ,  kala-azar of the Mediterranean Mediterrane an ty type pe and  L. braziliensis  sensu sensu la to . During a lifetime devoted to the study of these parasites, Adler (1947 (1947)) consistently stressed the great need for . . . som some e system of nomenclature nomenclatur e because the differe difference nces s betwe between en them are real, constant and of the greatest importance.

ADDENDUM Since this paper was written, we have noted that workers in Panama have discovered another  Leishmania,  similar mexicana icana ,  in the rodents of that country (Herrer, to  L. mex 1970). 197 0). Whether Whether or not this parasite is the same as L. mexicana amazonensis of amazonensis  of Brazilian rodents remains to be seen but, from the brief description given, it is clearly a member of the  L. mexicana complex. mexicana  complex.

REFERENCES

Adler,  S. (1940)  (1940)  Mems Inst. Oswaldo Cruz, 3 5,  173  trop. Med. Hyg.  40,  70 701 1 Adler,   S. (1947)  (1947)  Trans. R. Soc. trop.   2, 143 Adler,  S. (1962)  Sclent. Rep. 1st. sup. Sanitd, 2, Adler,  S. (1963)  Revta Inst. Salubr. Enferm. trop., Mix.  2 3,  139 Adler,  S. & Theodor,  O. (1957)  (1957) A.  Rev.  Ent. 2,  2,  203 Biagi,  F. F. (1953)  (1953) Medicina, Mix.  33, 401 Chagas,  E., Marques  da Cunha,  A., Castro Ferreira, L., Deane, L., Deane,   G., Guimaraes,  Guimaraes, F. N., Paumgartten,  Paumgartten, M. J. von & Sa, B . (1938) (1938)  Mems Inst. Oswaldo Cruz, 3 3 ,  89 Chagas,   E.,  Marques  da  Cunha,  A.,  Oliveira Castro,  G. de, Castro Ferreira,  L. &   & Romafia,  C. (1937)  (1937) Mems Inst. Oswaldo Cruz,  32, 321 Deane,  L. M. &  & Dean e, M. P. (1954)  Hospital, RiodeJ.  AS ,  419 Escomel, E. (1913)  Bull. Soc. Path. exot.  6, 237   237 [Letter] Floch, H. (1954)  Archs Inst. Pasteur Guyanefi.  Publ. 328, p. 1 Floch,  H. & Sureau,  P. (1953)  (1953)  Annls Parastt. Parastt. hum. comp. 2 8, 1  14 4 Garn h am , P. C. C. (1962)  (1962)  Sclent. Rep. 1st. sup. Sanitd,  2, 76 parasites and other HaemoGarnham,   P. C. C. (1966)   (1966)  Malaria parasites sporidia,   p. 64. Blackwell Scienti Scientific fic Publications, Oxford Herrer, A. (1970) /.  Parasit. 56, no. 4, sect.  sect. H, p. 144

Lainson,  K., Shaw,  Shaw, J. J. &   & Ii n s, Z. C  (1969) Trans. R. Soc. trop. Med. Hyg.   63, 741 Laveran,  A. & Nattan-Larrier, [L.] (1912)  Bull. Soc. Path. exot. 5,  176 Marques   da Cunha,  A. & Chagas, E. (1937)  Hospital, Rio de J. 11,148 Medina,  R. &  Romero,  J.  (1959)  Archos venez.  Med.  trop. Parasit.  mid. 3,  3, 298 Medina,  R. &  Romero,  J.  (1962)  Archos venez.  Med.  trop. Parasit.  mid. 4, 349 Migone,  L. E. (1913)  (1913) Bull. Soc. Path. exot.  6, 118 Muniz,  J. & Medina, H. (1948) Hospital, Rio deJ.  33 ,  7 Nery-Guimaraes,  F.,  Azevedo,  M. &  D a m a s c e n e  R.  (1966) Hospital,  RiodeJ.  70 ,  387 Nery-Guimaraes, F. & Costa, O.  R. da (1966) Hospital,  RiodeJ. 69,161 Nicolle,  C. (1908)  (1908) Archs Inst. Pasteur Tunis, 3 , 3 Noguchi,  H.  (1924)  In: Proc. int. Conf.  Hlth Probl. trop. Am., Kingston, Jamaica, July 22-August   1,  1924,  p. 455.  United Fruit Company, Boston, Mass.

Lainson,  (1966) T rans. *.. Sac. irup. Med. Hyg. 60,533 R. & Shaw, J. J. (1966) Lainson,  R. & Shaw, J. J. (1968)   (1968) Trans. R. Soc.  trop. Med. Hyg. 62,385 Lainson,  R. & Shaw, J. J. (1969)   (1969)  Trans. R. Soc.  trop. Med. Hyg. 63,408 [Letter] Lainson,  R. & Shaw, J. J. (1970)   (1970)  Trans. R. Soc.  trop. Med. Hyg. 64,654 Lainson, R. & Shaw, J. J. (197 (1971) 1) In : Fallis, A. M ., ed. Ecology and physiology of parasites: a symposium he ld at U niversity of Toronto, 19-20 February 1970,  p. 21 . University  University ofToronto Press, Toronto

 A. de M. 1,305 & Silva, P. D. da (1910)  Archos Soc. Med. Pedroso, Cirurg.   S  Paulo,  Hig. Saude  Hig.  Saude  publ.  2 Pessda, S. B. (1961) Archos 2 6, 41   Caracas,  48 ,  11 116 6 Pifano  G, F. (1940)  (1940)  Gac. mid. Caracas, 638 Schneider, C. R. (1968)   (1968) /. ParasU.  54 ,  638 Schneider, C. R. &  & H erti ertig, g, M. (1966) Expl Parasit.  18, 18, 25 Shaw, J. J. &   & Lainson, R. (1968)  (1968)  Trans. R. Soc. trop. Med. Hyg. 62,396 Ent.. 2, 171 Theodor,  O. (1965)  (1965) /.  med. Ent Velez, [L.] (1913) Bull. Soc. Path. exot. 6, 545 [Letter] 411 1 Vianna, G. (1911) Braz.-mid.  25 ,  41

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Br .  med Bull.  1972

D  o  w n l    o  a   d   e   d  f   r   o m  h   t    t    p  :   /    /    b  m  b   .  o x f    o r   d   j    o  u n r   a  l    s   .  o r   g  /      a   t    U n i    v  e  r   s  i    t    y  o f    C   a  l   i   f    o r  n i    a   ,  S   a  n F  r   a  n  c  i    s   c   o  o n F   e   b  r   u  a  r   y 2   3   , 2   0  1   5