**2. Epidemiology**

Leishmaniasis is the second most common parasitic disease in the world, with an estimat‐ ed 600,000 new cases per year [6]. It can also be considered an occupational disease, since it has affected workers in mining areas, geologists, scientific expeditions, military person‐ nel in training [2]. It has been documented in several countries, with an estimated preva‐ lence of 12 million worldwide [3]. More than 20 *Leishmania* species pathogenic to man have been described.

ment [15]. Risk factors for the development of mucosal Leishmaniasis are: the presence of lesions above the pelvis, large skin ulcers and inadequate treatment of cutaneous Leishma‐

For the diagnosis of mucosal Leishmaniasis, the clinical history and typical cutaneous scars have been considered as important clinical markers to corroborate the diagnosis of LM in

In the Americas, pre-Colombus pottery, made by the Indians of Peru, has been found, dating from 400 to 900 AD. These show mutilations of lips and noses, characteristics of espundia, today known as muco-cutaneous leishmaniosis. Subsequently, through studies in paleome‐ dicine, mummies with skin lesions and mucosas characteristic of Leishmaniasis were found [9]. Historical findings suggest that American Cutaneous Leishmaniasis (ACL) already affected the peoples of America before contact with Europeans and Africans. It is assumed that it may have originated in the western Amazon region during archeological times by means of human migrations and later ascended to the high jungle and then to the hot inter-Andean lands

In the Old World (Asia, Africa and Europe) written accounts of the disease date from the first century AD. About two thousand years later, in 1903, the agent of the disease is described for the first time and separately by LEISHMAN and DONOVAN. The disease was visceral

The first reference to American Tegumentary Leishmaniasis (ATL) in Brazil is in the document of the Religious Political-Geographical Pastoral 1827, quoted in Tello's book entitled "Anti‐ guidad de la Syfilis en el Peru", where he recounts the journey of Friar Don Hipólito Sanches de Fayas y Quiros de Tabatinga (AM) to Peru, which crossed the regions of the Amazon basin [9]. In 1911, GASPAR VIANNA gave the parasite found by Lindenberg the name *Leishmania* brasiliensis, because he considered it morphologically different from *Leishmania* tropica. This characterized, from then on, the etiological agent of the disease being referred to as "Bauru

In the 80s, the ATL was noted in 19 Federative Units (i.e. states), its geographical expansion being verified when, in 2003, autochthony was confirmed in all Brazilian states. It is seen to be widespread and, in some areas there is an intense concentration of cases, while in others, there are isolated cases [7]. The disease has been described in almost all American countries, from the extreme South of the United States to the North of Argentina, with the exception of Chile

Leishmaniasis is the second most common parasitic disease in the world, with an estimat‐ ed 600,000 new cases per year [6]. It can also be considered an occupational disease, since it has affected workers in mining areas, geologists, scientific expeditions, military person‐ nel in training [2]. It has been documented in several countries, with an estimated preva‐

Leishmaniasis and its agent, the species now known as *Leishmania donovani* [4].

patients with non-specific nasal/ oral granulomatous lesions [20].

46 Leishmaniasis - Trends in Epidemiology, Diagnosis and Treatment

across the frontiers of Bolivia and of Peru with Brazil [5].

ulcer", "angry angry" or "tapir-nose" [5].

and Uruguay [22].

**2. Epidemiology**

niasis [3].

Until the 1990s, the classification of these species was based primarily on clinical and geo‐ graphic criteria, taking into account on the one hand, the distinction between Old and New World, and, on the other, the clinical forms of the disease. This type of classification which has been progressively replaced by phylogenetic classification, is seen to be increasingly less tight and more superficial [4].

Leishmaniasis species are widely distributed and have been documented in Africa, Europe, Asia and America. In the Old World*, L. tropica, L. major* and *L. aethiopica*, which cause tegu‐ mentary Leishmaniasis, are identified as causal agents of the disease. In the Americas, several species of *Leishmania* are capable of causing tegumentary *Leishmania*sis, such as *L. braziliensis (LVB), L. amazonensis, L. guianensis, L. pananmensis* and *L. Mexicana.*

The characterization of *Leishmania* species that was initially made, considering the behavior of the parasite in the vector, today has biochemical and imminological and molecular biology techniques, by isoenzyme analysis, reactivity with monoclonal antibodies and analysis of the DNA of kinetoplast [3]. In the Americas, 11 dermotropic species of *Leishmania* causing human disease are currently recognized and 8 species desrcibed as being only in animals [8].

It is in Brazil that the largest prevalence in the whole American continent is found, this being estimated as 65,000 new cases per year [6]. The coexistence is observed of a double epidemiological profile, expressed by the maintenance of cases coming from old foci or areas near them, and by the appearance of epidemic outbreaks associated with factors arising from the emergence of economic activities, such as mining, expansion of agricultural frontiers and extractivism, in environmental conditions that are highly favorable to the transmission of the disease [8].

A great number of the houses in recent population settlements are built very close to the edge of the forest and individuals are affected by the radius of action of these vectors that reach houses and are also attracted by several factors such as lighting, the presence of sinantropic animals such as Didelphis marsupialis, domestic animals and man himself [1]. Some species of rodents, marsupials, edentates and wild canids have already been recorded as hosts and possible natural reservoirs. The reservoir-parasite intersection is considered a complex system, insofar as it is multifactorial, unpredictable and dynamic, and forms a biological unit which can be in constant change as a result of the changes in the environment [8].

The disease occurs, more habitually, in the form of epidemic outbreaks. Thus, the degree of exposure of the individuals affected is related directly to agricultural population settlements which were planned or more often arise from occupation processes on the outskirts of a city, most of which are disorganized [1].

Initially, the reservoirs of the mosquito transmitter were in the wild or in rural areas, but the environmental transformations, provoked by the migratory process and by the increasing urbanization have been modifying this profile. The adaptation of the vectors to the new conditions enabled the disease to spread in the domiciliary and peri- domiciliary settings [5]. In several regions of the country, such as in the South and Southeast, intense environmental changes occurred due to anthropic action and agricultural and pastoral activities, which led to the near disappearance of cutaneous Leishmaniasis in the late 40s. However, from the 70s and 80s Leishmaniasis has reappeared in these regions, with a significant increase in the number of new cases arising from endemic areas [1]. Transmission classically was due to the bite of an insect, the so-called insect vector. This insect, also called a sandfly, belongs in the Old World to the genus Phlebotomus, and in the New World, to the genus Lutzomyia [4].

The first cases of ATL in America date from 1885 and in Brazil, the first report was in 1909. In the period 1985-1999, there were 388,155 auctothon cases in Brazil of ALT; from 1999 to 2003, 33,872 cases of ATL a year were registered [1]. In the period from 2000 to 2009, an average of 24,684 confirmed cases of Leishmaniasis was registered in Brazil the Information System for Notifiable Diseases (SINAN) [14]. In 2003, the regions with the highest prevalence of LTA were the North (14,200 cases) and the Northeast (8,005 cases) [5].

In Brazil, 23,399 confirmed cases of ATL were notified in 2009, of which 94.1% were new cases and 4.6% relapses. With respect to clinical manifestations, 93.7% of patients had the cutaneous clinical form and 6.2%, clinical mucosa. Of all patients, in 2009, only 73.5% [17, 23] were cured, 16 patients died due to ATL, and 122 died from other causes, noting that 21.2% there was no information on the evolution of 21.2% of the cases [14].

It is estimated that every year there are new cases in Brazil and the growth of this number is due in part to the emergence and growth of AIDS and deforestation areas [2]. It mostly affects young and adult males [16]. The greater number of cases of American Tegumentary Leish‐ maniasis among men and adults suggests extra-domiciliary transmission in the economically active population, while this occurrence among women, children and people with nonagricultural occupations suggests intra- and or peridomiciliary transmission.

The transmission of ATL in the Amazon presents a clear seasonal variation, it being more intense in the rainy season, when the temperature, solar radiation and evaporation are lower and humidity higher, thus favoring an increase in the density of the phlebotominae, including the species involved in the cycle of the disease [1]. In endemic areas, there may be significant percentages of children with the disease [16].
