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Visceral
Leishmaniasis
(Kalaazar)
Dr. Natalia Oli
(MD, MPH, PhD )
Department of Community Medicine
Leishmaniasis. Epidemiology
• 14 million people are currently infected with Leishmania
• 700,000 to 1 million new cases occurring annually
• Every year Leishmaniasis causes 26,000 to 65,000
deaths
• An estimated 50 000 to 90 000 new cases of Visceral
Leishmaniasis occur worldwide each year (only 25-45%
reported to WHO)
• An estimated 600 000 to 1 million new cases of
cutaneouse leishmaniasis occur worldwide annually.
Leishmaniasis. Epidemiology
• Was an endemic in 88 countries on every continent
(except Australia and Antarctica)
• In 2015, more than 90% of new cases of Kalaazar
reported to WHO occurred in 7 countries: Brazil, Ethiopia,
India, Kenya, Somalia, South Sudan and Sudan.
• >2/3 of new cutaneous leishmaniasis cases occur in 6
countries: Afghanistan, Algeria, Brazil, Colombia, Iran
and the Syria
• Over 90% of mucocutaneous leishmaniasis cases
occur in Bolivia (the Plurinational State), Brazil, Ethiopia
and Peru
•
Status of endemicity of Visceral Leishmaniasis
worldwide, 2016
Agent - Leishmania
• 20 species of Leishmania
cause Leishmaniasis
• L. donovani is the causative
agent of Kalaazar
• L. tropica – cutaneous leishmaniasis (oriental sore)
• L. braziliensis – muco-cutaneous leishmaniasis
• But visceral forms may produce cutaneous lesions and
cutaneous form may visceralize
• There is no cross immunity of one against the other
species of Leishmania
Vector - the Phlebotomine sandfly
500 known phlebotomine species
(30 vectors of the disease)
• A protozoa transmitted by the bite
of a tiny 2 to 3 mm female sandfly
P. argentipes – Kalaazar
P. papatasi and P. sergenti –
Cutaneous leishmaniasis
Sand fly bite
• large, red itchy bumps
• may turn into a rash
• several times as itchy as mosquito bites, last longer
Vector - the Phlebotomine sandfly
• Breeds in small cracks and holes
in the ground, animal burrows,
cracks in mud walls and masonry,
and among tree roots
• Do not breed in water
• Overcrowding, bad ventilation,
accumulation of organic matter
• Usually bites in the evening
and at night
Way of transmission of VL
• Zoonotic disease (dogs, rodents, wolves, foxes, jackals)
• Zoonotic VL (animal - vector - human)
found in areas of L. infantum transmission
• Anthroponotic VL (human- vector – human) found in
areas of L. donovani transmission
Major risk factors for Leishmaniasis
• Socioeconomic conditions
• Malnutrition
• Population mobility
• Environmental changes
• Climate change
Risk for increased human exposure
to the sandfly worldwide:
man-made environmental changes
- mining
- building dams
- widening areas under cultivation
- new irrigation schemes
- road construction
- fast urbanization
Social determinants of risk
Gender
• Clinical disease M > F:
- more frequent exposure of males than females
- under detection of disease in women in traditionally
male-dominated societies
• Case fatality rate F > M:
- higher rates of malnutrition
- anemia in women
- longer delays in seeking care
Morphology of Parasite
• intracellular parasite (within macrophages)
• dimorphic parasite
• It exists in two entirely different morphological
structures, parasitizing in two different hosts:
promastigotes stage in sandfly
amastigotes stage in vertebrate host
Promastigotes stage
• Promastigotes stage of Leishmania exists in
sandfly.
Amastigote stage
in macrophages of reticuloendothelial system of
vertebrates
(spleen, liver, bone-marrow and lymph node)
Leishmaniasis - four main clinical
syndromes :
• Visceral Leishmaniasis (VL) (Kala-azar)
• Post-kala-azar dermal Leishmaniasis (PKDL)
• Cutaneous Leishmaniasis (CL)
• Muco-cutaneous Leishmaniasis (MCL) (espundia)
Visceral Leishmaniasis (VL)
• by two leishmanial species, L. donovani or L. infantum
Depending on the geographical area:
L. donovani (infects all age groups)
- India, Nepal and Bangladesh (more than 2/3 of all cases
of VL in the world)
- The East African (second largest focus of visceral
leishmaniasis - Ethiopia and Sudan)
L. Infantum (infects mostly children and immunosuppressed
individuals)
- the Middle East and western Asia , predominantly in Brazil
Visceral Leishmaniasis
• It is the most severe among leishmaniasis
• VL estimated incidence of 500,000 new cases and
60,000 deaths each year
• "Kala-Azar" (Kala - Black & Azar - Fever)
hyperpigmention with fever
• Always fatal if untreated
• Even with treatment, case-fatality rates often exceed
10% in VL-endemic areas of Asia and Africa
VL (Kalaazar). Clinical features
• Fever (more than 2 weeks)
• Splenomegaly
• Hepatomegaly
• Anemia
• Weight loss
• Darkening of the skin of face,
hands, feet and abdomen
Marked enlargement of the spleen typical of
visceral leishmaniasis in a patient in Nepal.
Hepatosplenomegaly (Visceral Leishmaniasis)
Cutaneous Leishmaniasis
• Skin ulcers on the exposed parts of the body such
as the face, arms and legs
• Large number of lesions (up to 200 )
- serious disability
- permanently scarred
Typical cutaneous leishmaniasis
ulcer (Guatemala)
Mucocutaneous Leishmaniasis
• Lesions can lead to partial or total destruction of the
mucous membranes of the nose, mouth and throat
cavities and surrounding tissues
• Almost 90% of mucocutaneous leishmaniasis cases
occurs:
- Bolivia
- Brazil
- Peru
Post-kala-azar dermal leishmaniasis (PKDL)
• Macular, maculo-papular or nodular rash
(nodular lesions contain many parasites)
• Cause by L. donovani, complication of VL (common
in Sudan and rarely in the Indian sub-continent)
• However, there are cases without any previous
known history of VL
• Can also occur in immunosupressed individuals in
L. infantum endemic areas
Leishmania-HIV co-infection
• VL accelerates HIV replication and progression to AIDS
• Cause severe forms of visceral and cutaneous
leishmaniasis that are more difficult to manage
• Antiretroviral treatment reduces the development of the
disease, delays relapses and increases the survival of the
co-infected patients.
• High leishmania-HIV coinfection rates are reported from
Brazil, Ethiopia and the state of Bihar in India.
Global distribution of reported cases of
Leishmania/HIV co-infection,1990-1998 (WHO)
Visceral Leishmaniasis:
National situation and responds
Nepal
• 12 endemic districts, and 2 regions:
6 - Eastern Development Region (EDR)
6 - Central Development Region (CDR)
• Approximately 7.5-8 million populations at
risk
• There are few PKDL cases identified.
Elimination of Kalaazar. National response
• Nepal, India, Bangaldesh – elimination of Kalaazar by
2015 (memorandum of understanding World Health
Assembly 2005)
• In 2005, Epidemiology and Disease Control Division
(EDCD) of Department of Health Services - National
Plan for the Elimination of Kala-azar
• Three phases:
Preparatory Phase: 2005-2008
Attack Phase: 2008-2015
Consolidation Phase: 2015 onwards
National Plan for the Elimination of Kala-azar
Goal
• Reduce incidence of Kala-azar to less than 1 case per
10,000 populations at district level by 2015.
Objectives
• Reduce the incidence of Kala-azar in endemic
communities with special emphasis on poor, vulnerable
and unreached populations.
• Reduce case fatality rates from Kala-azar to ZERO.
• Detect and treat Post-Kala-azar dermal leishmaniasis
(PKDL) to reduce the parasite reservoir.
• Prevent and manage Kala-azar HIV–TB co-infections.
National Plan for the Elimination of Kala-azar
Strategies
• Improve Program Management
• Early Diagnosis and Complete Treatment
• Integrated Vector Management
• Effective Disease and Vector Surveillance
• Social Mobilization and Partnerships
• Clinical, Implementation and Operational Research
Elimination of Kalaazar. National response
• The national plan was revised in 2010 as National
Strategic Guideline on Kala-Azar Elimination in Nepal
• Recommended rK39 as a rapid diagnostic test kit:
- high sensitivity and specificity
- available up to PHC centre level
• Liposomal Amphotericin B (L-AmB) as the first line
regimen during the attack phase in the Indian subcontinent
(introduced in Nepal in December 2015)
• Miltefosine
The rK39 dipstick test
Major activities: Case Detection and Treatment
• Diagnostic and treatment services are provided at primary
health care centre (PHC)
• RDT scaling up
• Identification and referral of suspected cases are also
offered at HP
• Active case detection activity in 5 most endemic VDCs
each of Morang, Saptari and Sarlahi districts (camp)
• House to house search (by the FCHVs )
• Disease surveillance
Major activities: Reservoir and Vector Control
Indoor Residual Spraying
• Two rounds per year in prioritised Kala-azar affected
areas of 12 districts
• Repeated at regular interval to keep down the density of
sandflies
Combined with sanitation measures:
- elimination of breeding places
- location of cattle sheds at the distance from houses
Insecticide- impregnated materials
Trend of Kala-azar cases and deaths (Source: EDCD)
Trend of kala-azar cases
2015/16 2016/17
2017-18
Native Foreign Native Foreign Native Foreign
Programme
Districts
181 17 151 6 122 0
Other districts 69 0 74 0 117 0
Total 250 17 225 6 239 0
The incidence trend of Kala-azar (Nepal)
2007/08 2008/09 2009/10 2014/15 2015/16 2016/17
Incidence
per
10,000
1.71
1.33
0.95
0.25
0.12
0.11
Kala‐azar cases and incidence: 2016- 2018
Thank you
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