INFECTIOUS AGENT

  • Strongyloides stercoralis, a nematode

  • larvae penetrate skin, enter blood vessels, travel to lungs, migrate up respiratory tree to the pharynx, where they enter the gastrointestinal tract (where the female lays eggs)

MODE OF TRANSMISSION

  • penetration of skin or mucous membrane by infective larvae (usually from fecally contaminated soil)

  • free-living form of the parasite can be maintained in the environment (soil) for years

  • transmission also occurs via oral-anal sexual activities

DISTRIBUTION

  • worldwide; most common in tropical and subtropical areas

INCUBATION PERIOD AND COMMUNICABILITY

  • larvae can be found in stool 2 to 3 weeks after exposure

  • infection is potentially communicable as long as living worms remain in the intestine

TREATMENT

  • antiparasitic agents: thiabendazole, albendazole, ivermectin

PREVENTION AND CONTROL

  • disposal of feces in a sanitary manner

  • avoidance of skin-soil contact in endemic areas

FACTORS FACILITATING EMERGENCE

  • international travel

  • immunosuppression

Toxoplasma gondii

DISEASE(S) AND SYMPTOMS

Toxoplasmosis

  • a systemic protozoan disease, frequently present as an acute mononucleosis-like disease (malaise, myalgias, fever)

  • immunocompromised persons tend to have severe primary infection with pneumonitis, myocarditis, meningoencephalitis, hepatitis, chorioretinitis, or some combination of these



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