2. B. malayi from blood smear
using Giemsa stain.
• Scientific classification
Kingdom:Animalia
Phylum:Nematoda
Class:Chromadorea
Order:Rhabditida
Family:Onchocercidae
Genus:Brugia
3. Burgia
Brugia is a genus for a group of small roundworms. They are among
roundworms that cause the parasitic disease filariasis. Specifically, of the three
species known, Brugia malayi and Brugia timori cause lymphatic filariasis in
humans; and Brugia pahangi and Brugia patei infect domestic cats, dogs and
other animals.They are transmitted by the bite of mosquitos.
Species
Brugia malayi
Brugia timori
Brugia pahangi
4. History
• Steffen Burg discover B. malayi in malaya ( Southeast Asia ) 1927.
• Burgia timori was firstly described in 1965 in Timor.
5. Geographical distribution
• B. Malayi infects 13 million people in south and
southeast Asia and is responsible for nearly 10% of
the worlds total cases of lymphatic filariasis.
6. Morphology
• Female adult worms measure between 43 – 55
mm in length by 130 – 170 um in width.
• Male adult worms measure between 13 – 23
mm in length by 70 – 80 um in width.
7. Life cycle
Brugia roundworms complete their life cycle in two different hosts. Mosquitos are the
intermediate host in which the young larvae develop, and thus they are also the vectors of
filariasis. Different species of Mansonia and Aedes act as the intermediate hosts. Humans
(for B. malayi and B. timori), and animals (for B. pahangi and B. patei) acts as the definitive
hosts in which the adult worms cause filariasis. The infective larvae called L3 (third stage)
larvae are transmitted by an infected mosquito onto the skin of the definitive host. Once
reaching the blood stream, they grow into adult roundworms. Male and female worms
reproduce to release the young worms called microfilariae. These microfilariae move to
peripheral blood stream from where they are picked up by another mosquito. Inside the
mosquito, they became larvae, first L1 and then L3. The L3 larvae are stored in the
proboscis from where they are ejected into the host during biting.
10. • Lymphedema (elephantiasis):
Lymphedema is a build-up of lymph fluid in the fatty tissues just under
your skin. This build-up might cause swelling and discomfort. It often
happens in the arms or legs, but can also happen in the face, neck,
abdomen
12. Diagnosis
• Examination of thick blood smear.
• Serological test (e.g ELIZA).
• PCR (Polymerase chain reaction)
• Microfilariae can be detected in urine in case of chyluria.
14. Prevention and control
The best way to prevent lymphatic filariasis is to avoid mosquito bites.
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.
