Unpasteurized milk, dairy products, mayonnaise, and pastry icing are associated with increased risk for TD, as are foods and beverages purchased from street vendors and other establishments where unhygienic conditions may be present. Water
Although safe bottled water is now widely available in most remote destinations, travelers can treat their own water if necessary, or as an extra precaution. Techniques include boiling, filtering, chemical treatment, and ultraviolet light; boiling is by far the most effective of these methods. Boiling rapidly kills all active bacteria, viruses, and protozoa. Prolonged boiling is usually unnecessary; most microorganisms are killed within seconds at water temperature above 55–70 °C (130–160 °F). The second-most effective method is to combine filtration and chemical disinfection. Filters eliminate most bacteria and protozoa, but not viruses. Chemical treatment with halogens—chlorine bleach, tincture of iodine, or commercial tablets—have low-to-moderate effectiveness against protozoa such as Giardia, but work well against bacteria and viruses. UV light is effective against both viruses and cellular organisms, but only works in clear water, and it is ineffective unless manufacturers instructions are carefully followed for maximum water depth/distance from UV source, and for dose/exposure time. Other claimed advantages include short treatment time, elimination of the need for boiling, no taste alteration, and decreased long-term cost compared with bottled water. The effectiveness of UV devices is reduced when water is muddy or turbid; as UV is a type of light, any suspended particles create shadows that hide microorganisms from UV exposure. Medications
Bismuth subsalicylate four times daily reduces rates of travelers diarrhea.
Iridodonesis () is the vibration or agitated motion of the iris with eye movement. This may be caused by lens subluxation, the incomplete or partial dislocation of the lens; or by aphakia, the absence of a lens. The term originated from irido- (Latin: iris) + doneo (Greek: δονεο, to shake to and fro). See also
Phacodonesis

References
External links
An example of iridodonesis on YouTube