FILARIASIS

By Micaela Yanez

OUTLINE

Introduction of Filariasis History Transmission Epidemiology Progress of Lymphatic Filariasis The Disease Symptoms and Treatments

WHAT IS FILARIASIS

A disease that affects humans and animals and iscaused by nematode parasites of the order Filariidae.

Of the 100 described filarial parasites only 8 speciescause infection in humans.

The 8 filarial parasites are classified by the location theyinhabit in host

CLASSIFICATION OF FILARIALPARASITES

1st group- Cutaneous (of the skin) Loa loa Onchocerca volvulus Mansonella streptocerca

2nd group- Lymphatic (Lymphatic system) Wuchereria bancrofti Brugia malayi Brugia timori

3rd group- Body Cavity Mansonella perstans Mansonella Ozzardi

LYMPHATIC FILARIASIS

"a parasitic disease caused by threadlike worms livingin the human lymphatic system."

The "threadlike worm" that can cause lymphaticfilariasis is a blood-dwelling filarial nematode, from theaschelminth phyla

3 known species: Wuchereria bancrofti Brugia malayi Brugia timori

WHAT ARE THE DIFFERENCE?

Differences between W. bancrofti,B. malayi and B. timori reside inepidemiology, vectors, reservoirs,symptoms, but mainly speciesmorphology.

WUCHERERIA BANCROFTI

well-documented most widespread cause of lymphatic

filariasis morphologically significantly different

from the other species

Wuchereria bancrofti in a bloodsmear

BRUGIA MALAYI

Vector and reservoir Transmitted by Mansonia mosquitos Animal reservoirs Morphology differences

BRUGIA TIMORI

Least common Least studied More similar to W. bancrofti that to B. malayi Vector Anopheles barbirostris No known animal reservoirs Symptoms and morphology resembles B. malayi Larger then B. malayi

HISTORY OF LYMPHATIC FILARIASIS

Timeline of discovery 2000BC Pharaoh Mentuhotep II 500 AD Nok civilization in West Africa Greek and Roman civilization 1588-1592 symptoms 1849- symptoms 1863 and 1866- microfilariae 1876- adult worm 1877- life cycle 1900- transmission

TRANSMISSION

A wide range of mosquitoes can transmitthe parasite, depending on thegeographic area.

In Africa, the most common vector isAnopheles

In the Americas, it is Culexquinquefasciatus, and Aedes

Mansonia can transmit the infection inthe Pacific and in Asia. Anopheles

AedesCulex quinquefasciatusMansonia titillans

TRANSMISSION

EPIDEMIOLOGY

Endemic in approx. 80 countries 120 million infected 40 million seriously incapacitated or disfigured India, Indonesia, Nigeria, & Bangladesh =70% 1/3 of infected live in India 1/3 of infected live in Africa Remainder are in South Asia, the Pacific and South

America

Most of the infections worldwideare caused by Wuchereriabancrofti.

In Asia, the disease can also becaused by Brugia malayi andBrugia timori.

Microfilaria of Wuchereria bancrofti,top image.

Microfilaria of Brugia malayi, bottomimage. (CDC Photos; DPDx)

EPIDEMIOLOGY

PROGRESSION OF LYMPHATIC FILARIASIS

Adult W. bancrofti worms with the smaller male on the leftand larger female on the right

3 STAGES OF PROGRESSION

* Prepatent Period* Incubation Period* Chronic Stage of Lymphatic Filariasis

THE DISEASE Elephantiasis

The individuals above are all infected with W. bancrofti.

DIAGNOSIS

ICT Test X-Ray Detection Blood Test

PREVENTION AND TREATMENT

there is no known vaccine or cure forlymphatic filariasis

Diethylcarbamazine (DEC) is apopular microfilaricide, and has beenused in Mass Drug Treatmentprograms.

symptoms are often treated withantihistamines, and antibiotics

ERADICATION

Lymphatic filariasis is one of sevendiseases worldwide that the WHO hastargeted for eradication

Global Alliance to Eliminate LymphaticFilariasis

REVIEW

What is filariasis How its transmitted Where its found The disease Treatment, Prevention, and Eradication

REFERENCES Center for Disease Control and Prevention. 2007. Lymphatic Filariasis. Accessed online at

http://www.cdc.gov/ncidod/dpd/parasites/lymphaticfilariasis/

Dreyer, G., Noroes, J., Figueredo-Silva, J., and Piessens, W.F. 2000. Pathogenesis of LymphaticDisease in Bancroftian Filariasis: A clinical Perspective. Parasitology Today. 16:545-550.

John, David T. and William A. Petri Jr. "Brugia malayi." Medical Parasitology. 9th ed. St. Louis,Missouri: Saunders Elsevier, 2006. 285-289.

John, David T. and William A. Petri Jr. "Wuchereria bancrofti ." Medical Parasitology. 9th ed. St.Louis, Missouri: Saunders Elsevier, 2006. 274-285.

John, David T. and William A. Petri Jr. "Wuchereria bancrofti ." Medical Parasitology. 9th ed. St.Louis, Missouri: Saunders Elsevier, 2006. 274-285.

John, David T. and William A. Petri Jr. "Brugia timori." Medical Parasitology. 9th ed. St. Louis,Missouri: Saunders Elsevier, 2006. 287-289.

Melrose, Wayne D. 2002. Lymphatic filariasis: new insights into an old disease. InternationalJournal of Parasitology. 32:947/960.

The Global Alliance to Eliminate Lymphatic Filariasis. Accessed April 2009 at http://www.filariasis.org/.