Cercarial dermatitis

Infectious diseases

Clinicals - History

Fact Explanation
Skin rash Cercarial dermatitis, also known as swimmer's itch, is an itchy allergic reaction caused by larvae of Schistosoma cercariae parasites in class trematoda that enter the skin. Swimmer's itch develops on exposed areas of the skin after contact with these larval forms when they mistakenly penetrate the person's skin rather than its usual host, a duck. The rash does not occur following the initial contact. Repetitive exposure develop a stronger hypersensitivity reaction. Initial itchy or tingling sensation usually settles quickly, leaving the infected individual with tiny red spots at the sites of larvae penetration. After several hours those red spots develop into papules (raised bumps) or hives (a rash of round, red , itchy weals). Within the next 1-2 days they blisters (a small bubble on the skinfilled with watery liquid) develop which may spontaneously resolves with time. Skin rash
Cercarial dermatitis, also known as swimmer's itch, is an itchy allergic reaction caused by larvae of Schistosoma cercariae parasites in class trematoda that enter the skin. Swimmer's itch develops on exposed areas of the skin after contact with these larval forms when they mistakenly penetrate the person's skin rather than its usual host, a duck. The rash does not occur following the initial contact. Repetitive exposure develop a stronger hypersensitivity reaction. Initial itchy or tingling sensation usually settles quickly, leaving the infected individual with tiny red spots at the sites of larvae penetration. After several hours those red spots develop into papules (raised bumps) or hives (a rash of round, red , itchy weals). Within the next 1-2 days they blisters (a small bubble on the skinfilled with watery liquid) develop which may spontaneously resolves with time.
Itching As the larvae of schistosoma enters the exposed skin a itchy or tingling sensation appears. But this settles within 1-2 hours. After few hours of asymptomatic period, an acute onset itching reappears in a more extensive form due to the allergic reaction. Abrasions caused by severe itching can predispose to secondary bacterial infections. Itching
As the larvae of schistosoma enters the exposed skin a itchy or tingling sensation appears. But this settles within 1-2 hours. After few hours of asymptomatic period, an acute onset itching reappears in a more extensive form due to the allergic reaction. Abrasions caused by severe itching can predispose to secondary bacterial infections.
Population at risk Individuals who go often for swimming in lakes and rivers where migrating aquatic birds inhibits have a risk of getting exposed. The infestation is more common in the hot summer weather. It is more common among children who does not wear swimming suits. Population at risk
Individuals who go often for swimming in lakes and rivers where migrating aquatic birds inhibits have a risk of getting exposed. The infestation is more common in the hot summer weather. It is more common among children who does not wear swimming suits.

Clinicals - Examination

Fact Explanation
Rash Tiny red spots at the sites of larvae penetration is an early sign. Monomorphic maculopapular eruptions in parts of the human skin that comes in contact with the infecting water can be inspected. Blister formation occurs a day after the exposure. Itching may results in secondary bacterial infections. Rash
Tiny red spots at the sites of larvae penetration is an early sign. Monomorphic maculopapular eruptions in parts of the human skin that comes in contact with the infecting water can be inspected. Blister formation occurs a day after the exposure. Itching may results in secondary bacterial infections.

Management - Supportive

Fact Explanation
Protective ointments Mild itching will be resolved spontaneously. If the itching is spread in a wide area, when the reaction begins, the skin should be lightly rinsed with isopropyl alcohol and then coated with calamine lotion. Protective ointments
Mild itching will be resolved spontaneously. If the itching is spread in a wide area, when the reaction begins, the skin should be lightly rinsed with isopropyl alcohol and then coated with calamine lotion.
Anti-inflammatory drugs Antihistamines and topical corticosteroids (1% hydrocortisone) may be beneficial to suppress the allergic reaction and thereby provides symptomatic relief for both itching and rash. If the reaction is severe, oral steroids (prednisone) may be appropriate. Anti-inflammatory drugs
Antihistamines and topical corticosteroids (1% hydrocortisone) may be beneficial to suppress the allergic reaction and thereby provides symptomatic relief for both itching and rash. If the reaction is severe, oral steroids (prednisone) may be appropriate.
Antibiotics Abrasions caused by severe itching can predispose to secondary bacterial infections. Topical antibiotic skin creams such as fucidin, mupirocin or oral cloxacillin can be used. Antibiotics
Abrasions caused by severe itching can predispose to secondary bacterial infections. Topical antibiotic skin creams such as fucidin, mupirocin or oral cloxacillin can be used.
Epsom salts Bathing in epsom salt (Magnesium sulfate) added water provides symptomatic relief for itching. Bath sprinkled with oatmeal is an alternative. Epsom salts
Bathing in epsom salt (Magnesium sulfate) added water provides symptomatic relief for itching. Bath sprinkled with oatmeal is an alternative.
Sodium bicarbonate Sodium bicarbonate (baking soda) has found to be one of the most effective treatments. Topical application as a paste or bathing sprinkled with sodium bicarbonate provides instant relief from itching. Sodium bicarbonate
Sodium bicarbonate (baking soda) has found to be one of the most effective treatments. Topical application as a paste or bathing sprinkled with sodium bicarbonate provides instant relief from itching.
Prevention Toweling immediately after leaving the water may be helpful as a primary preventive method before the larvae enter the exposed skin. Because the cercariae are present in greatest concentration in shallow, warmer water (where the snails are), swimmers should try to avoid these areas. Niclosamide is a antihelmintic drug. Water resistant sun cream with 0.1%-1% niclosamide has been shown to be highly effective. Treating waterfowl which includes ducks, geese and fowls (hosts for schistosma) in order to reduce transmission has been considered. [1.2,3,4,5] Prevention
Toweling immediately after leaving the water may be helpful as a primary preventive method before the larvae enter the exposed skin. Because the cercariae are present in greatest concentration in shallow, warmer water (where the snails are), swimmers should try to avoid these areas. Niclosamide is a antihelmintic drug. Water resistant sun cream with 0.1%-1% niclosamide has been shown to be highly effective. Treating waterfowl which includes ducks, geese and fowls (hosts for schistosma) in order to reduce transmission has been considered. [1.2,3,4,5]

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