Japan The infection occurs without any age, gender, racial or ethnic bias Individuals in the United States typically do not develop Heterophyiasis, unless the infection sets in from travel to the endemic regions What are the Risk Factors for Heterophyiasis? Predisposing Factors The risk factors for Heterophyiasis may include: Eating undercooked or raw fish that contains encysted encased in a shell H. This stage of larvae is called the metacercaria stage Not washing hands after handling infected raw fish Not cleaning cooking utensils after preparing a meal containing infected fish Individuals with occupations, such as fishing, which can result in exposure to infected fish Living in areas of the world where H. Some risk factors are more important than others. Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.
|Published (Last):||3 February 2017|
|PDF File Size:||11.67 Mb|
|ePub File Size:||3.52 Mb|
|Price:||Free* [*Free Regsitration Required]|
The trematode Heterophyes heterophyes, a minute intestinal fluke. The miracidia undergo several developmental stages in the snail, i. Many cercariae are produced from each redia. The definitive host becomes infected by ingesting undercooked or salted fish containing metacercariae.
After ingestion, the metacercariae excyst, attach to the mucosa of the small intestine and mature into adults measuring 1. In addition to humans, various fish-eating mammals e.
Egypt, the Middle East, and Far East. Clinical Presentation The main symptoms are diarrhea and colicky abdominal pain. Migration of the eggs to the heart, resulting in potentially fatal myocardial and valvular damage, has been reported from the Philippines. Migration to other organs e. Adult of Heterophyes heterophyes. Adults of Heterophyes heterophyes are minute flukes, measuring mm in length.
The tests are large and paired, and are situated near a small ovary. The surface of the worm is covered with minute spines. Adults reside in the small intestine of the definitive host.
Figure A: Adult of H. Like all trematodes, Heterophyes heterophyes requires a snail as an intermediate host.
Cerithideopsilla cingulata is the main first intermediate host for H. Figure A: Cerithideopsilla cingulata, an intermediate host for H. Image courtesy of Conchology, Inc, Mactan Island, Philippines Laboratory Diagnosis The diagnosis is based on the microscopic identification of eggs in the stool. However, the eggs are indistinguishable from those of Metagonimus yokogawai and resemble those of Clonorchis and Opisthorchis.
DPDx is an educational resource designed for health professionals and laboratory scientists. For an overview including prevention, control, and treatment visit www. Page last reviewed: January 3,
In Egypt, after looking at twelve populations of Cerithideopsilla conica , which is mud snail and carrier of Heterophyes heterophyes, it was found that the most infected snails were found in the Nile Delta compared to the Red sea coast and inland waters of the Delta. The eggs are hard to tell apart from other related species so there is no accurate estimate of human infection. Their sucker mouth is covered with spikes and its covering the genital opening. This means, they share one hole for eating and reproduction.