Nematode disease

1. Wuchereria bancrofti
K.Kamatchi
Assistant Professor
Department of Zoology
Vivekananda College
Tiruvedakam West

2. INTRODUCTION
Phylum : Aschelminthes
Endoparasite – Lymph node
Commonly called – Filarial
Worm
Viviparous – Microfilaria

3. Sexual Dimorphism

4. Hosts of Wuchereria – Digenic
Parasite
Primary Host – Man Secondary Host – Culex Mosquito

5. Development is Indirect

6. Life Cycle
Adult lymphatic system of man
Microfilariae
Blood
Stomach of Culex
Thoracic Muscle of Culex
First stage larva

7. Second stage larva
Third stage larva
Proboscis of culex
Human body
Elephantiasis

8. Pathogenesis
• 6-12 months incubation period
• There are 3 phases of infections:
• Asymptomatic
• inflammatory (acute)
• and obstructive.

9. Pathogenesis Continued…
• Asymptomatic Phase:
– High levels of microfilaria in the blood
– No symptoms present
• Inflammatory (Acute) Phase:
– Inflammatory responses happen in response to antigens
from adult worms
• Lymphedema—swelling due to blockage of lymph
vessels
• Orchitis—inflammation of the testes
• Epididymitis — inflammation of the spermatic cord

10. • Obstructive Phase:
– Lymph varices—enlarged
lymph vessels
– Lymph scrotum
– Chyluria—lymph in urine
(milky and sometimes
bloody urine)
– Elephantiasis—
enlargement of limbs and
thickening of the skin due
to repeated inflammatory.

11. Filariasis
• Endemic in 83 countries
• 1.2 billion at risk
• More than 120 million people infected
• More than 25 million men suffer from
genital symptoms
• More than 15 million people suffer from
lymphoedema or elephantiasis of the leg

12. Diagnosis
• Thick blood smear
– Juveniles must be present in peripheral blood
• Ultrasonography
– Detects vigorous movement of adults known as “filaria dance sign”
• X-rays
– Detects dead, calcified worms

13. Control Measures
• Elimination of common
mosquito breeding
grounds
– Fallen coconuts
– Any small container
– filled with waterUnder
ground drainage
system.
• Spraying Insecticides
• Mosquito nets
• Propellants

14. Treatment
• Consumption of
• Diethylcarbamazine
(DEC)
– reduces microfilariae
concentrations
– kills adult worms
• Albendazole
– kills adult worms
• Ivermectin
– kills the microfilariae
produced by adult worms

15. Thank you