Source of Infection For Humans and Transmission
Human F. hepatica infection is determined by the presence of the intermediate snail hosts, domestic herbivorous animals, climatic conditions and the dietary habits of man. Sheep, goats and cattle are considered the predominant animal reservoirs. While other animals can be infected, they are usually not very important for human disease transmission. On the other hand, some authors have observed that donkeys and pigs contribute to disease transmission in Bolivia. Among wild animals, it has been demonstrated that the peridomestic rat (Rattus rattus) may play an important role in the spread as well as in the transmission of the parasite in Corsica. In France, nutria (Myocastor coypus) was confirmed as a wild reservoir host of F. hepatica. Humans are infected by ingestion of aquatic plants that contain the infectious cercariae. Several species of aquatic vegetables are known as a vehicle of human infection. In Europe, Nasturtium officinale (common watercress), Nasturtium silvestris, Rorippa amphibia (wild watercress), Taraxacum dens leonis (dandelion leaves), Valerianella olitoria (lamb's lettuce), and Mentha viridis (spearmint) were reported as a source of human infections. In the Northern Bolivian Altiplano, some authors suggested that several aquatic plants such as bero-bero (watercress), algas (algae), kjosco and tortora could act as a source of infection for humans. Because F. hepatica cercariae also encyst on water surface, humans can be infected by drinking of fresh untreated water containing cercariae. In addition, an experimental study suggested that humans consuming raw liver dishes from fresh livers infected with juvenile flukes could become infected.
Read more about this topic: Fasciolosis
Famous quotes containing the words source of infection, source of, source, infection and/or humans:
“Anti-Semitism is a horrible disease from which nobody is immune, and it has a kind of evil fascination that makes an enlightened person draw near the source of infection, supposedly in a scientific spirit, but really to sniff the vapors and dally with the possibility.”
—Mary McCarthy (1912–1989)
“The dream of reason produces monsters. Imagination deserted by reason creates impossible, useless thoughts. United with reason, imagination is the mother of all art and the source of all its beauty.”
—Francisco José De Goya Y Lucientes (1746–1828)
“Dear sensibility! source inexhausted of all that’s precious in our joys, or costly in our sorrows!... eternal fountain of our feelings!—’tis here I trace thee—and this is thy divinity which stirs within me ...—all comes from thee, great—great SENSORIUM of the world!”
—Laurence Sterne (1713–1768)
“What, then, was war? No mere discord of flags
But an infection of the common sky
That sagged ominously upon the earth”
—Robert Graves (1895–1985)
“The worst condition of humans is when they lose knowledge and control of themselves.”
—Michel de Montaigne (1533–1592)