Sand fly Phlebotomus spp Leishmania Infection and Treatment

Sand fly : Phlebotomus spp Leishmania: Infection and Treatment by Mahmoud Lubbad

classification of Leishmania • The leishmaniases include a complex of vector-borne diseases, caused by more than 20 species of the protozoan genus Leishmania, and ranging from localized skin ulcers to lethal systemic disease. Leishmaniasis is classified as one of the "most neglected diseases, " based on the limited resources invested in diagnosis, treatment and control, and its strong association with poverty.

Phlebotomine Sand Flies… Order: Diptera Family: Psychodidae Genera: ● New World ● Lutzomyia ● Brumptomyia ● Warileia ● Old World ● Phlebotomus ● Sergentomyia (Aranasy et al. , 1999 and Martin-Sanchez et al. , 2000)

Morphology • Adults - small (less than 5 mm long) with conspicuous black eyes, long narrowly obovate wings that form a V-shaped out line above thorax, wing veins are parallel to each other , slender with piercing mouthparts and long antennae; There are fine hairs on body, wings and legs.

C. L by year 1995 to 2011 G ﺍﻟﻌﺎﻡ ﺑﺸﻜﻞ ﻋﺎﻡ ﻋﺪﺩ . 2011 ﻋﺪﺩ ﺍﻟﺤﺎﻻﺕ ﺍﻟﺠﻨﺴﻴﺔ ﺳﻌﻮﺩﻱ ﻏﻴﺮ ﺳﻌﻮﺩﻱ 1995 ﻡ 6383 3229 3154 1996 ﻡ 5402 3081 2321 1997 ﻡ 6009 3725 2284 1998 ﻡ 5351 3432 1919 1999 ﻡ 5687 3596 2091 2000 ﻡ 4753 3010 1743 2001 ﻡ 2002 ﻡ 2003 ﻡ 2004 ﻡ 2005 2006 2007 2008 2009 2010 2011 3953 4454 3842 4132 3883 3602 3286 2321 2549 4131 1951 2269 2654 2023 2145 2003 1846 1609 1286 1232 2177 1015 1684 1800 1819 1987 1880 1756 1677 1035 1317 1954 936 ﺍﻹﺻﺎﺑﺔ ﻟﻠﺴﻌﻮﺩﻳﻴﻦ ﺃﻌﻠﻲ ﻣﻦ ﻏﻴﺮ ﺍﻟﺴﻌﻮﺩﻳﻴﻦ ﻭﺃﻘﻞ ﻋﺪﺩ ﻟﻠﺤﺎﻻﺕ ﻛﺎﻥ ﻋﺎﻡ

Habits • Only female sandflies are blood sucker and they are nocturnal feeders. • They are poor flier and fly in a characteristic hopping, 30 -1000 m, not over 200 m. • Prevalent from May to September. Larvae survive through the winter.

Hematophagous diptera(flies) are of two basic types : Capillary feeders : mouth parts are inserted into the skin and blood is withdrawn directly (solenophages). Pool feeders : mouthparts short and are used to lacerate the skin the blood flow and ingested by the fly (temophages).

Female feed on blood at night. Sand flies are pool feeder ( telmophages ) which suck blood from a small wound they make in the skin. Their bite is therefore relatively painful.

- Sand flies do not produce a buzzing or whining noise before biting which again reduces the perceived nuisance to man. -Color of sand flies are brownish in day light , but their bodies are densely covered in oily hairs which give them whitish appearance when illuminated

ﺫﻛﺮ ﺃﻨﺜﻰ Adult male and female sandfly

Pharynx Maxillary palp ﺫﻛﺮ ﺃﻨﺜﻰ Mouth parts of sandfly

Phlebotomus A- Maxilla B- Mandible A ﺃﻨﺜﻰ B

Life cycle (stages) • • • Eggs are laid in dark humid animal burrows, cracks or crevices, or under dead leaves (Egg laid on moist dark place containing organic debris ( under leaves on the ground , in damp mossy place , in rank vegetation or on hallow tree trunks ). There are 4 larval instars, the larval stage lasting a total of 4 -6 weeks The pupa requires 10 days for development LC requires 40 -50 days Only adult females suck blood Adult life span 2 -3 weeks, 30 -50 eggs/female.

- Sand fly bite: The bite in indudurated, inflamed with a wheal of 1 -2 cm. and accompanied by pruritus lasting for hours or weeks and sometime with systemic allergic reaction (fever, nausea, malaise swelling of the bitten member). - Treatment: Topical application of phenolated camphor in mineral oil or anesthetic ointment.

1. Leishmaniasis is transmitted by the bite of female phlebotomine sandflies. The sandflies inject the infective stage, promastigotes, during blood meals. 2. Promastigotes that reach the puncture wound are phagocytized by macrophages. 3. They transform into amastigotes. 4. Amastigotes multiply in infected cells and affect different tissues. 5. Sandflies become infected during blood meals on an infected host when they ingest macrophages infected with amastigotes. 6. In the sandfly's midgut, the parasites differentiate into promastigotes. 7. They multiply and migrate to the proboscis.

AMASTIGOTES PROMASTIGOTES

LIFE CYCLE

Leishmania fact sheet What are Leishmania parasites? ·Protozoan parasites (proto = first; zoan = animal) ·Small (usually microscopic) single-celled organisms ·Life cycle can be divided into 2 stages depending on the host: · Sand fly vector = Leishmania promastigotes · Human or other vertebrate = Leishmania amastigotes Life cycle of Leishmania parasites Multiplication Release from macrophages Transformation Sand fly Promastigotes ingestion inoculation Vertebrate host Amastigotes Multiplication and reinfection Attachment and phagocytosis Transformation Leishmania amastigotes Leishmania promastigotes Flagellum Form of Leishmania within human or other vertebrate host’s cells (have resorbed their flagellum) • Size: 2 -6 mm • Shape: ovoid • Characteristics: central nucleus Form of Leishmania within sand fly vector: • Can move in the direction of their flagellum • Can be cultured Different parasites cause different forms of the disease Cutaneous lesihmaniasis Visceral lesihmaniasis

EARLY DIAGNOSIS • L. D BODIES (SPLEEN, BONE MARROW, LYMPH NODE) • ALDEHYDE TEST • ELISA & Polymerize chain reaction (PCR)

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