Lymphatic Filariasis/Elephantiasis:Causative Agent/ EtiologyIt is caused by thread-like parasitic worms like Wuchereria

bancrofti, Brugia malayi, and B. Timori.

Mode of transmission/Epidemiology: Transmitted by mosquitoes' bites like Culex, Aedes, and

Anopheles species.Signs and Symptoms: enlargement of the arms, legs, or genitals to elephantoid size. kidney damage

Preventive measures:As with malaria, the most effective method of controlling the spread of W.bancrofti and B.malayi is to avoid mosquito bites.Sleep under a bed netWear long sleeves and trousersUse mosquitoes repellent, especially at night.Improved and proper sanitation and environmental management.

Treatment:Maintaining careful hygiene in the infected persons to reduce the incidence and spread of secondary infectionsAnti-filariasis medicines like Diethylcarbamazine (DEC)

reduces microfilariae concentrations kills adult worms

Albendazole kills adult worms

Ivermectin kills the microfilariae produced by adult worms

Hookworms and diseases- AmaemiaCausative Agent/ EtiologyIt is caused by roundworms - Necator americanus and A duodenale.Soil contaminated with human faeces.

Mode of transmission/EpidemiologyHookworm transmission occurs by skin contact with infective third-stage larvae that have the ability to penetrate through the skin, mainly via hands, feet, arms, or legs.Then larvae are carried through the veins to the heart and then to the lungs. They penetrate into the pulmonary alveoli, ascend the bronchial tree to the pharynx, and are swallowed. The larvae reach the small intestine, where they reside and mature into adults. Adult worms live in the lumen of the small intestine, where they attach to the intestinal wall with resultant blood loss by the host- Anemia.

Diseases cause by Hookworms:

Hookworm disease are primarily referred to the iron-deficiency

anaemia with reduced host haemoglobin.

In children, chronic hookworm infection has been shown to

impair physical and intellectual development, reduce school

performance and attendance, and adversely affect future

productivity and wage-earning potential.

Signs and symptoms:Easy fatigue and loss of energyUnusually rapid heart beat, particularly with exerciseShortness of breath and headache, particularly with exerciseDifficulty concentratingDizzinessPale skinLeg crampsInsomnia

Preventive measures:Educational campaigns about the proper use of latrinesSanitary disposal of human faecesWearing any footwear may also be useful and helpful

Treatment:Medications like albendazole, mebendazole, and pyrantel pamoate all are effective treatments anti-hookworm vaccine have also used to killed the larvae in infective larvae in stage three.

Pinworms and infection- Infection is Enterobiasis

Causative Agent/ EtiologyEnterobius vermicularis-roundworm.

Mode of transmission/Epidemiology

Egg transmission occurs by the fecal-oral route either directly

or indirectly via contaminated hands or fomites such as shared

toys, bedding, clothing, toilet seats, and baths.

Preventive measures:Good hygiene will help reduce the spread of the parasites. Hand washing after handling things with infective pinworm eggs.Cleaning under the fingernails and not biting the fingernails.Clothes, especially underwear, should be changed and washed daily to help prevent spreading the disease. Treating every infected in a household at the same time. .

Signs and symptoms:In minor cases: Itching around the anal area, Difficulty sleeping and irritability.In severe cases includes:Nervousness Restlessness Loss of appetite Weight loss Girls may experience vaginal itching and irritation (vaginitis), if

pinworms are near the vagina.

Treatment:

Usually a single tablet of mebendazole (Vermox) is used for treatment

Another effective medication is albendazole (Albenza)

Pyrantel pamoate (Pin-Rid, Pin-X) is available over-the-counter for pinworm infection has been confirmed

Liver fluke and diseases:The adult lives in the liver of hosts, feeding on blood and liver cells called liver-rotMainly infect liver, bladder and rectum

Causes and causative agentIt is cuased Fasciola Hepatica and disease is Fasciolosis

Fasciola hepatica is a parasitic fluke that lives mainly in the liver. In addition to humans it infects cows and sheep.

Mode of transmission/:EpidemiologyTwo hosts:1. Primary hosts are vertebrate- sheep, cattle and human2. Secondary hosts are non-vertebrate- snails. When a female lays eggs in the liver of an infected human.

Immature eggs are discharged in the biliary ducts and taken out in the faeces. If landed in water, the eggs become embryonated and develop larvae . That larvae invades an aquatic snail and develops a larva with a large tail capable of swimming. Then the particular larva exits and finds aquatic vegetation where it forms a cyst/metacercaria. A human eats the raw freshwater plant containing the cyst. The cyst/metacercaria enters in the first part of the small intestine, duodenum. It then penetrates the intestinal wall and gets into the peritoneal cavity. It finds the liver and starts eating liver cells. Then it relocates to the bile duct where it begins its final stage and becomes an adult.

Cont………The cattle and sheep are infected by eating faeces contaminated with grasses.

Preventive measures: Keeping sheep away from the snail contaminated areas where

ponds are dried up in high summer. Keeping the ducks away from snails in damp meadows as they

are useful predators. Avoid eating raw watercress and other water plants, especially

from endemic grazing areas.

Signs and symptoms:

In the chronic phase stage it causes:liver inflammation and obstruction of the biliary fluid. During the migration of the larvae - acute phase of the disease symptoms include:DiarrheaEosinophilia-high number of white blood cells.FeverNauseaStomach acheVomiting.

Treatment:Triclabendazole is the drug of choice. It is given by mouth, usually in

one or two doses.

The treatment recommended will depend on the nature of the disease.

Some of the available anthelmintics are not effective against

immature fluke and so are not recommended in acute fluke

outbreaks.

Types1. Acute fasciolosis.

May be due to seasonal and climatic conditions combined with a

lack of fluke control measures; typically, stock forced to graze in

heavily contaminated wet areas Animals suffering from acute

fasciolosis may not show any obvious symptoms. Some animals

may show abdominal pain and may become jaundiced. Death is

usually due to blood loss resulting from haemorrhage in the liver.

2. Subacute fasciolosis

Subacute fasciolosis is characterized by jaundice, some ill thrift

and anaemia. Fluke causes extensive tissue damage, leading to

hemorrhaging and liver damage.

3. Chronic fasciolosis.

The most common form of liver fluke infection . It occurs when

the parasites reach the bile ducts in the liver. The fluke ingests

blood, which produces severe anaemia and chronic inflammation

and enlargement of the bile ducts. The clinical signs develop

slowly. The animals become increasingly anaemic, appetite is

lowered, the mucous membranes of the mouth and eyes become

pale and some animals develop oedema under the jaw

Refereces

Boray, J.C. (March 2007).Liver fluke diseases . Retrieved 13th October 2011 from

(www.dpi.nsw.gov.au/__.../liver-fluke-disease-in-sheep-and-cattle.pdf

Liver Fluke – Fasciola Hepatica(n.d.) Retrieved 6th October 2011 from

en.wikipedia.org/wiki/Fasciola_hepatica.

 

Liver Flukes (n.d.). Retrieved 6th October 2011 from

http://www.unbc.ca/nlui/wildlife_diseases_bc/liver_flukes.htm 

ELEPHANTIASIS(n.d.) . Retrieved 6th October 2011 from

www.lfhk.cuni.cz/patfyz/edu/...9/ELEPHANTITIS[1].ppt

Cleeg,C.G. & Mackean, D.G.(2004). Advanced Biology- Principles and Applications

( 2nd ed.) London: Hodder Murray Headline group.