leishmaniasis

introduction

leishmaniasis is a disease caused by protozoan parasites that belong to the genus Leishmania and is transmitted by the bite of certain species of sand fly.
human infection is caused by about 21 of 30 species that infect mammals.
affects as many as 12 million people worldwide:
- 30,000 new VL cases of and more than 1 million new CL cases each year
- > 90% of annual VL incidences occur in six countries: Bangladesh, Sudan, India, Nepal, Ethiopia, Brazil and South Sudan
- East Africa is the second largest center of VL after the Indian continent and annually adds 30,000–40,000 new cases per year
visceral form is the second-largest parasitic killer in the world (after malaria), responsible for an estimated 500,000 cases each year worldwide
a disease characterized by high epidemiological dynamism related to constantly changing transmission conditions depending on the environment, demography, human behavior, socio-economic status and the human immune system ¹⁾

found in tropics and sub-tropics, in rainforests to deserts
mainly in the developing world
more than 90% of the world's cases of visceral leishmaniasis are in India, Bangladesh, Nepal, Sudan, and Brazil
found across much of Asia, though not Southeast Asia
found in Middle East including Saudi Arabia, Iraq, and Afghanistan (esp. Kabul due to poor sanitation)
cases in Africa, particularly east and north, and spreading to southern Europe
- historically, Catania in Sicily has been an urban focus for this disease as over 80% of the urban area has the sand flies (highest numbers in Sept) of which over 10% are infected, however there seem to be only around 10 reported human infections there each year.²⁾ The far majority of human cases in Sicily actually occur in the NW provinces of Palermo and Agrigento. Infection rates of dogs in Sicily seem to be 25-34% whilst that of cats is 12%. Rates of canine infection are 50% less in Ragusa compared to most other provinces of Sicily.
found through much of the Americas from northern Argentina to southern Texas, though not in Uruguay or Chile.
- aka papalomoyo, papa lo moyo and ulcero de los chicleros in Latin America
NOT found in Australia or Oceania

clinical leishmaniasis is prevalently a disease of poverty and malnutrition although immunocompromise by HIV / AIDS is an increasing factor for severe disease

skin sores which erupt weeks to months after the person affected is bitten by sand flies
heals in a few months to a year, leaving an unpleasant-looking scar
can progress to the other 3 forms.

severe form in which paraistes have migrated to vital organs
potentially fatal if untreated
aka kala-azar, black fever, and Dumdum fever
delayed onset of fever, weight loss, mucosal ulcers, fatigue, marked hepatosplenomegaly and anaemia
the blackening of the skin that gave the disease its common name in India does not appear in most strains of the disease, and the other symptoms are very easy to mistake for those of malaria.
increasing issues with co-infection with HIV / AIDS
some time after successful treatment, generally a few months with African kala-azar, or as much as several years with the Indian strain, a secondary form of the disease may set in, called post kala-azar dermal leishmaniasis, or PKDL

widespread skin lesions which resemble leprosy, and is particularly difficult to treat.

starts as skin ulcers then spreads to cause tissue damage especially to mouth and nose

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