Travel advice (prevention of traveller's diarrhoea)

• dietary advice
• the following foods and beverages should be avoided
  • raw or undercooked fish, meat and seafood, unpasteurised milk, cheese, ice cream and other dairy products, tap water and iced cubes, cold sauces and toppings, ground grown leafy greens, vegetables and fruits, cooked food s that have stood at room temperature in warm environments, food from street vendors
• hygiene measures
• render water potable by
  • bringing it to a rolling boil (may not always be convenient)
  • Chemical treatments –
    • Chlorine preparations are usually effective, but protozoan parasites such as Cryptosporidium and Giardia are not always inactivated by these agents (chlorine dioxide to be more effective at inactivating parasites )
    • using a water filter that has a filter size of ≤0.2 µm to 1.0 µm before using a chemical disinfectant is helpful remove suspended matter and parasites
    • iodine is no longer sold or supplied for use in disinfecting drinking water from October, 2009
• washing hands after visiting the toilet, and always before preparing or eating food (alcohol gel can be helpful when hand-washing facilities are not available)
• recreational water
• travellers should avoid ingesting water when participating in recreational activities such as swimming, wading
• should avoid swimming when travellers have open cuts, abrasions, or other wounds that could serve as entry points for pathogens
• should not enter the water if suffering from TD to avoid contamination
• travelers should avoid pools and interactive fountains if the water is cloudy.
• chemoprophylaxis
• non-antibiotic products
  • bismuth subsalicylate (BSS)–
    • studies have shown that BSS taken daily as either 2 oz of liquid or 2 chewable tablets 4 times per day reduces the incidence of TD by approximately 50%
    • may cause blackening of the tongue and stool and may cause nausea, constipation, and rarely tinnitus.
    • not recommended for children aged <3 years and should be avoided in patients with aspirin allergy, renal insufficiency, and gout and by those taking anticoagulants, probenecid, or methotrexate.
  • probiotics - may reduce the likelihood of travellers’ diarrhoea,
• antibiotics
  • not recommended for most travelers
  • useful in cases where a trip is vitally important or the consequences of watery diarrhoea would be difficult to manage (for example, after colostomy or ileostomy).
  • refer prophylaxis and treatment for traveller’s diarrhoea link for antibiotic regimes
• vaccines
• cholera vaccine may provide some limited cross protection against diarrhoea caused by Escherichia coli producing a heat-labile enterotoxin (unlicensed in the UK for this use)
• medication - there is an increased incidence of intestinal infection if a patient is taking H2-antagonist or PPI medication. The risk of infection can be minimised by taking reducing doses (if possible) and taking medication at night (when the risk of infection is lower) (1,2,3).

Travellers can get more information about dietary advice from the guidelines on food and water hygiene but should keep in mind that these measures do not offer full protection against TD (3)

Reference:

• (1) Centers for Disease Control and Prevention (CDC) 2013. Yellow Book. Chapter 2 - For the Record: A History of the Definition & Management of Travelers’ Diarrhea
• (2) Hill DR, Ryan ET. Management of travellers' diarrhoea. BMJ. 2008;337:a1746.
• (3) National Travel Health Network and Centre (NaThNaC). Travel health information sheet. Traveller’s diarrhoea