Information about a disease caused by nematode which is ascariasis also known as filariasis or elephantiasis.

1. FILARIASIS
AKSHMALA SHARMA

2. INTRODUCTION
Filariasis is mainly caused by the parasite Wuchereria bancrofti carried by the mosquito
• variant parasites: Brugia malayi & B. timori
• affects >90 million people worldwide: 2/3rd in China, India & Indonesia
• WHO: 2nd most common cause, after leprosy, of long-term disability

3. PATHOGENESIS
Once bitten by the
mosquito, the matured
eggs enter the human
circulation and grow to
hatch into adult worms;
the process of maturation
takes about one year. The
adult worms mainly
colonise the lymphatic
system.

4. CLINICAL FEATURES
• episodic attack of fever
• lymhadenitis
• lymphangitis…recurrent-> fibrosis of lymphatic
channels
• massive lower limb deem
skin thickening (obstruction of cutaneous lymphatics)
secondary streptococcal infection
B/L lower limb filariasis often associated with scrotal &
penile elephantiasis
chyluria
chylous ascites
mild respiratory symptoms: dry cough *tropical pulmonary
eosinophilia

6. INVESTIGATION
• eosinophilia
• nocturnal peripheral blood smear: microfilariae
(immature forms)
• urine, ascites, hydrocele fluid: parasite

7. TREATMENT
• diethylcarbamazine 2mg/kg TID for 12 days or as a single
dose or albendazole 400mg with ivermectin
200microgram/kg in a single dose with or without DEC
(early stage-before gross deformities)
• intermittent pneumatic compression (early stage of limb
swelling)
• hydrocoele: excision & eversion of the sac with if
necessary excision of redundant skin

8. Other animals
Filariasis can also affect domesticated animals, such as cattle, sheep, and dogs.
Cattle
Verminous hemorrhagic dermatitis is a clinical disease in cattle due to Parafilaria bovicola.
Intradermal onchocerciasis of cattle results in losses in leather due to Onchocerca dermata, O.
ochengi, and O. dukei. O. ochengi is closely related to human O. volvulus (river blindness),
sharing the same vector, and could be useful in human medicine research.
Stenofilaria assamensis and others cause different diseases in Asia, in cattle and zebu.
Horses
"Summer bleeding" is hemorrhagic subcutaneous nodules in the head and upper forelimbs,
caused by Parafilaria multipapillosa (North Africa, Southern and Eastern Europe, Asia and South
America)
Dogs
Heart filariasis is caused by Dirofilaria immitis.

9. Prevention & Control
The best way to prevent lymphatic filariasis is to avoid
mosquito bites. The mosquitoes that carry the microscopic
worms usually bite between the hours of dusk and dawn . If
you live in an area with lymphatic filariasis:
•At night
• Sleep in an air-conditioned room or
• Sleep under a mosquito net
•Between dusk and dawn
• Wear long sleeves and trousers and
• Use mosquito repellent on exposed skin