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Infantile visceral leishmaniasis (IVL) is considered a rare and neglected disease in Egypt. An outbreak of the disease in El Agamy, Alexandria occurred in 1982 although the disease was previously reported 80 years before. Epidemiological and entomological studies were conducted ever since the 1982 outbreak to identify human cases, the parasite, reservoir host and the sand fly vector. Leishmania infantum MON-98, a new and unique zymodeme, was responsible of the disease. Stray dogs acted as the reservoir host and Phlebotomus langeroni was the proven vector. The parasite isolates from human cases were identical to the parasite isolates from the reservoir host and the sand fly vector. The El Agamy focus in 1982 was basically a rural Bedouin setting of recently built cement houses surrounded by lime stone fences. The numbers of human cases of IVL in this area have been declining, with the last reported case in 2005. This coincides with the completion of irregular urbanization of El Agamy which resulted in the disappearance of P. langeroni. In this review, we characterize the old focus of IVL in El Agamy based on published literature to identify factors underlying the appearance and disappearance of the disease., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Visceral leishmaniasis (VL) is a disease of chronic evolution which could be uniformly fatal, if left untreated. Human VL was first described in the Americas in 1913 and in 1936 in Brazil. The number of VL cases in Brazil is increasing steadily in the last three decades. Medical literature highlights this change in the disease epidemiology as a recent urbanization phenomenon, with most of the cases occurring in large cities since 1981, different to that observed previously, like a typical rural endemic. The aim of this study was to create a narrative review of the evolution of VL epidemiology since its first description in Brazil. To describe the process of urbanization of VL, timeframes were created historically consistent with the scientific and public health knowledge obtained about the VL and the demographics changes in Brazil, especially considering the extensive migratory movements in the country due to political or economic events. The first phase of VL was the decades of 30-50 when industrialization triggered internal migration process from countryside to the cities; during this period VL was studied for the first time and described as a rural endemic disease with no relevance to public health. Until the second phase, between the 50s and 80s of the 20th century, demography was characterized by expansion of immigration to the large cities and increase in population density in the suburbs with poor living standards. In this period, there was an advancement in the knowledge of the transmission of the disease being described as the first case acquired in the urban environment. The third phase was characterized by the explosion of cases in Brazilian cities and consolidation of urban endemic transmission. The possibility of urban transmission has been known since the 50s; however, the current phenomenon was due to the creation of ideal conditions for the establishment of transmission cycle in Brazilian cities.

Background: Visceral leishmaniasis has been targeted for elimination as a public health problem (less than 1 case per 10,000 people per year) in the Indian sub-continent by 2017. However, there is still a high degree of uncertainty about the natural history of the disease, in particular about the duration of asymptomatic infection and the proportion of asymptomatically infected individuals that develop clinical visceral leishmaniasis. Quantifying these aspects of the disease is key for guiding efforts to eliminate visceral leishmaniasis and maintaining elimination once it is reached., Methods: Data from a detailed epidemiological study in Bangladesh in 2002-2004 was analysed to estimate key epidemiological parameters. The role of diagnostics in determining the probability and rate of progression to clinical disease was estimated by fitting Cox proportional hazards models. A multi-state Markov model of the natural history of visceral leishmaniasis was fitted to the data to estimate the asymptomatic infection period and the proportion of asymptomatic individuals going on to develop clinical symptoms., Results: At the time of the study, individuals were taking several months to be diagnosed with visceral leishmaniasis, leading to many opportunities for ongoing transmission. The probability of progression to clinical disease was strongly associated with initial seropositivity and even more strongly with seroconversion, with most clinical symptoms developing within a year. The estimated average durations of asymptomatic infection and symptomatic infection for our model of the natural history are 147 days (95 % CI 130-166) and 140 days (95 % CI 123-160), respectively, and are significantly longer than previously reported estimates. We estimate from the data that 14.7 % (95 % CI 12.6-20.0 %) of asymptomatic individuals develop clinical symptoms-a greater proportion than previously estimated., Conclusions: Extended periods of asymptomatic infection could be important for visceral leishmaniasis transmission, but this depends critically on the relative infectivity of asymptomatic and symptomatic individuals to sandflies. These estimates could be informed by similar analysis of other datasets. Our results highlight the importance of reducing times from onset of symptoms to diagnosis and treatment to reduce opportunities for transmission.

In the 19(th) century, a devastating epidemic of visceral leishmaniasis (kala-azar) swept through northeast India. After identification of the pathogenic agent, Leishmania donovani, in 1903, the question of its transmission remained to be resolved. In 1904, thanks to work by L. Rogers on cultures of this parasite it became probable that a haematophagous arthropod was responsible for transmission. J.A. Sinton suggested, in 1925, the distribution of the sand fly Phlebotomus argentipes was similar to that of the disease and, thereafter, two independent teams led by H.E. Shortt in Assam and R. Knowles and L. Napier in Calcutta concentrated on this potential vector. Parallel work was in progress in China, directed by E. Hindle and W. S. Patton for the Royal Society Kala-azar Commission, on another species of sand fly. In 1942 the Assam workers transmitted L. donovani to five human volunteers by the bites of colonised P. argentipes and the race was over.

In the second part of their review the authors focus on palaeopathological studies, performed in mummified tissues, with reference to infectious diseases. The analysis of samples obtained from both natural and artificial mummies may provide, in some favourable events, a more complete knowledge of these findings in comparison to information obtained from only comprehensive examination of the skeleton. The acquired data enable us to understand not only the diseases which afflicted mankind, but also dietary and hygiene conditions of ancient populations. We report knowledge acquired regarding some palaeopathological conditions, including schistosomiasis, smallpox, cisticercosis, trichinosis, ascaridiasis, echinococcosis, filariasis, hepatitis E virus, condylomatosis, pulmonary tubercolosis, pediculosis, visceral leishmaniasis as well as Diphyllobotrium sp., Dicrocoelium dendriticum and Fasciola hepatica infestations. In addition some interesting findings concerning the relationship between dietary and food intake colonized by streptomyces are described. This review reports the discovery of human remains from different geographic areas: while most of these studies describe findings in two Mediterranean countries (Italy and Egypt), some refer to Britain and German-speaking countries (Austria and Germany) as well as the area in Africa known as Nubia, along the Nile. Both histological and biomolecular diagnosis are useful not only to identify a specific disease in a subject from the remote past, but also to achieve information concerning its frequency and evolution. Such knowledge may thus allow us to understand the intensity of cultural exchanges and links among different populations and the role of these relationships in transmitting and spreading infectious diseases in a certain geographic area.

Kala-azar was a lethal disease in colonial India. Charles Donovan of the Indian Medical Service (IMS) in Madras discovered the parasite independently in 1903 while William Boog Leishman was carrying out his research in Great Britain. Donovan's discovery ended the confusion prevalent over the anomalous and puzzling cases of malarial fevers in India and proved they were not related to malaria. This added to the promotion of medical knowledge, initiated further research and created enthusiasm among medical scientists throughout the world. Donovan was the first person to see the kala-azar parasite in the peripheral blood and thus provided a clue to the carriage and transmission of the kala-azar parasite by the insect through peripheral blood. Donovan's research on kala-azar also convinced the government of its utility and the need for further investigation; he fell victim to professional rivalry.

Throughout the world, pentavalent antimonial compounds (Sb(v)) have been the mainstay of antileishmanial therapy for more than 50 years. Sb(v) has been highly effective in the treatment of Indian visceral leishmaniasis (VL: kala-azar) at a low dose (10 mg/kg) for short durations (6-10 days). But in the early 1980s reports of its ineffectiveness emerged, and the dose of Sb(v) was eventually raised to 20 mg/kg for 30-40 days. This regimen cures most patients with VL except in India, where the proportion of patients unresponsive to Sb(v) has steadily increased. In hyperendemic districts of north Bihar, 50-65% patients fail treatment with Sb(v). Important reasons are rampant use of subtherapeutic doses, incomplete duration of treatment and substandard drugs. In vitro experiments have established emergence of Sb(v) resistant strains of Leishmania donovani, as isolates from unresponsive patients require 3-5 times more Sb(v) to reach similarly effectiveness against the parasite as in Sb(v) responders. Anthroponotic transmission in India has been an important factor in rapid increase in the Sb(v) refractoriness. Pentamidine was the first drug to be used and cured 99% of these refractory patients, but over time even with double the amount of initial doses, it cures only 69-78% patients now and its use has largely been abandoned in India. Despite several disadvantages, amphotericin B is the only drug available for use in these areas and should be used as first-line drug instead of Sb(v). The new oral antileishmanial drug miltefosine is likely to be the first-line drug in future. Unfortunately, development of newer antileishmanial drugs is rare; two promising drugs, aminosidine and sitamaquine, may be developed for use in the treatment of VL. Lipid associated amphotericin B has an excellent safety and efficacy profile, but remains out of reach for most patients because of its high cost.

The leishmaniases comprise several diseases of wide diversity of manifestations caused by different species of the genus Leishmania. They are grouped under three main headings: Cutaneous leishmaniasis, visceral leishmaniasis and mucocutaneous leishmaniasis. Leishmania donovani complex which visceralize in man with a predilection for infecting cells in the viscera, particularly in the spleen and the main vectors are Phlebotomus of the "major" group. These include L.d. donovani (Asia, mainly India and China), Ld. infantum (Mediterranean countries) infects mainly children and L.d. chagasi (South America) infects adults and children. In this paper, the historical background of L. donovani and L. infantum with special reference to Egypt is given. Not all the previous references were included, but many of them were cited. Comment was given whenever indicated.

This paper reviews the evidence of a link between flood control and vector-borne disease in Bengal/Bangladesh. Malaria is historically associated with reduced flooding and embankment construction in the flood plains of Bengal. The land west and south of the Jamuna river was highly malarious in 1916 but is not so today. The lands east of the Jamuna now have a higher, though still small, risk. The reduction in health risk can be attributed to the intensification of land use and human population density. Although there are many mosquito species, the abundance of the former malaria vector appears to have declined as environmental change removed its breeding sites. Visceral leishmaniasis (kala-azar) is a serious disease which is fatal if left untreated. It occurs in irregular, periodic epidemics and is currently increasing in Bangladesh. In the past, malaria and kala-azar were confused and the prevalence of both may have been increased by embankment programmes. Both diseases are unstable and there is insufficient historical information to predict, with certainty, the consequences of environmental change. Reduced flooding accompanied by increased pollution will probably control the malaria vector. More information is needed about the response of the kala-azar vector to flooding. Bancroftian filariasis is non-fatal but causes chronic morbidity. It has had a widespread but usually low prevalence in Bangladesh, with both rural and urban foci. There are few recent data. Increasing organic pollution and drainage obstruction are expected to favour the vector and increase transmission.

A bibliographic-historical review of leishmaniasis in Spain during the period 1912-1985 is carried out. The bibliographical prospecting has allowed to collect a total of 402 works; out of them only 79 are included in this review. From reading them, it can be deduced that, starting from its discovery in the coast of Levante in 1912, leishmaniasis has been a very well known disease in Spain, during the first third of our century, period in which a remarkable prevalence took place, as it follows from the works published basically by Pittaluga and colleagues. In them, plentiful clinical and epidemiologic data are collected, many of them having laid the foundations of this disease knowledge in our country. Nevertheless, the extrapolation of data from other geographical regions introduced confusions, which have continued till recent time, basically on what refers to the existing relation between the aetiological agent and the clinical case. On the other hand, nowadays, current important matters such as the part of person's immune response in the appearance of a visceral or cutaneous case of leishmaniasis, independently from the parasites specific identity or the presence of asymptomatic leishmaniasis, are already found in pioneer works. In the course of the work, a review is made of the information, obtained form the Spanish bibliography, on the leishmaniasis aetiological agent in Spain, the vector and the host as well as the various clinical cases of human and canine leishmaniasis, their epidemiology, diagnostic and treatment.