Key points
- Most cases of zoonotic hookworm infection resolve without treatment.
- Medication may be required for severe cases or to control symptoms and resolve secondary bacterial infections.
- Treatment with albendazole or ivermectin are curative.
Treatment options
Since the zoonotic hookworm larvae usually will die after 5 – 6 weeks in the human host, the course of CLM is considered self-limiting. However, some reports have described delayed onset and persistent clinical diseases.
Treatment may be indicated to help control symptoms and to resolve secondary bacterial infections. Various treatment modalities have been proposed, including cryotherapy and topical anthelminthic therapy. However, these treatments require localization of the larvae for effect, which is usually not possible.
Repeated application of topical anthelminthics over large areas of skin has been shown to be effective in some cases, but this may be impractical.
Treatment recommendations
Treatment with albendazole or ivermectin are curative. In severe or relapsing cases, especially with folliculitis, additional doses may be necessary. Children younger than 2 years of age or under 15 kg body weight may be treated with topical preparations.
Oral albendazole is available for human use in the United States. Oral ivermectin is available for human use in the United States.
Drug
Adult Dose
Pediatric Dose
Albendazole
400 mg per day by mouth for 3 to 7 days
Children aged > 2 years: 400 mg per day by mouth for 3 days
This drug is contraindicated in children younger than 2 years age.
Ivermectin
200 mcg/kg by mouth as a single dose
Children over 15 kg weight: 200 mcg/kg by mouth as a single dose
Care Precautions
Note on Treatment in Pregnancy
Albendazole is pregnancy category C. Data on the use of albendazole in pregnant women are limited, though the available evidence suggests no difference in congenital abnormalities in the children of women who were accidentally treated with albendazole during mass prevention campaigns compared with those who were not. In mass prevention campaigns for which the World Health Organization (WHO) has determined that the benefit of treatment outweighs the risk, WHO allows use of albendazole in the 2nd and 3rd trimesters of pregnancy. However, the risk of treatment in pregnant women who are known to have an infection needs to be balanced with the risk of disease progression in the absence of treatment.
Pregnancy Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the fetus.
Note on Treatment During Lactation
It is not known whether albendazole is excreted in human milk. Albendazole should be used with caution in breastfeeding women.
Note on Treatment in Pediatric Patients
The safety of albendazole in children less than 6 years old is not certain. Studies of the use of albendazole in children as young as one year old suggest that its use is safe. According to WHO guidelines for mass prevention campaigns, albendazole can be used in children as young as 1 year old. Many children less than 6 years old have been treated in these campaigns with albendazole, albeit at a reduced dose.
Note on Treatment in Pregnancy
Ivermectin is pregnancy category C. Data on the use of ivermectin in pregnant women are limited, though the available evidence suggests no difference in congenital abnormalities in the children of women who were accidentally treated during mass prevention campaigns with ivermectin compared with those who were not. The World Health Organization (WHO) excludes pregnant women from mass prevention campaigns that use ivermectin. However, the risk of treatment in pregnant women who are known to have an infection needs to be balanced with the risk of disease progre ssion in the absence of treatment.
Pregnancy Category C: Either studies in animals have revealed adverse effects on the fetus (teratogenic or embryocidal, or other) and there are no controlled studies in women or studies in women and animals are not available. Drugs should be given only if the potential benefit justifies the potential risk to the fetus.
Note on Treatment during Lactation
Ivermectin is excreted in low concentrations in human milk. Ivermectin should be used in breast-feeding women only when the risk to the infant is outweighed by the risk of disease progress in the mother in the absence of treatment.
Note on Treatment in Pediatric Patients
The safety of ivermectin in children who weigh less than 15kg has not been demonstrated. According to the WHO guidelines for mass prevention campaigns, children who are at least 90 cm tall can be treated safely with ivermectin. The WHO growth standard curves show that this height is reached by 50% of boys by the time they are 28 months old and by 50% of girls by the time they are 30 months old, many children less than 3 years old been safely treated with ivermectin in mass prevention campaigns, albeit at a reduced dose.