Page 99 - Medical Parasitology_ A Textbook ( PDFDrive )

92 10 Nematodes: Roundworms

Treatment
Albendazole (400 mg orally once) or mebendazole (100 mg orally twice/day for 3
days or 500 mg orally once). Pyrantel pamoate (11 mg/kg (up to a maximum of 1 g)
orally daily for 3 days) is also effective and can be used in pregnancy. Iron supple-
ment is given to correct anaemia. In severe cases, blood transfusion may be needed.
When the haemoglobin level is very low, antihelminthic drugs should not be given
before correcting the anaemia.

Prevention and Control
Same as for Strongyloides

Animal Nematodes That Can Infect Human

Animal nematodes can infect human causing cutaneous larva migrans (CLM) and
visceral larva migrans (VLM).

Cutaneous Larva Migrans (CLM)

This condition also known as creeping eruption is caused by animal nematode lar-
vae that penetrate skin of human. The most common cause is dog and cat hookworm
(Ancylostoma braziliense) and dog hookworm (Ancylostoma caninum). Since
human is an abnormal host, the parasite cannot develop into adults. The larva will
migrate in the human skin till it dies.

Pathogenesis and Clinical Features
Hookworm eggs are passed in the faeces of infected animals into the soil, where the
eggs hatch and release larvae. On coming into contact with human skin, the infec-
tive larvae penetrate the skin to cause infection. Since human is an abnormal host,
the larvae remain confined to the outer layer of the skin. The larvae produce itching
papules, which develop into serpigenous tracks in the epidermis. Itchiness causes
scratching which may lead to secondary bacterial infection.

Diagnosis
Diagnosis is based mainly on history and clinical manifestations.

Treatment
Albendazole, 400 mg orally once/day for 3–7 days. Thiabendazole ointment is use-
ful in treatment. When the lesions are few, freezing the advancing part of the lesion
with ethyl chloride is effective. Symptomatic relief can be given for pruritus.

Prevention and Control
1. Deworming of dogs and cats
2. Wearing shoes when going outdoor