What viruses cause Travellers diarrhoea?

The word “diarrhoea” often sounds gross and for those who have it for days will obviously say it is one of the very uncomfortable experiences. While diarrhoea in general may go away eventually even without specific medication, some may need medicine from doctors to get better. It is important to treat diarrhoea especially when it occurs in vulnerable groups such as children and elderly. In this DoctorOnCall’s article, we will be learning about one of the many kinds of diarrhoea known as Travelers diarrhoea (TD).

Traveler’s diarrhoea is a clinical syndrome as a result of infections such as bacteria, virus or parasites, sourced from contaminated food or water. Just as the name implies, it is one of the common illnesses among travellers who travel to destinations with low levels of hygiene and sanitation. There are 35 to 60% chances to get TD during a month-long trip to a lesser developed country. This means that the risk will always be related to the destination, level of accommodation and travel habits. Risk is also high in regions with lack of safe water and lack of refrigeration. High-risk areas include most of Asia, Africa and Central or South America which are always in warmer climates. TD can occur in both short and long term travellers. Hence, there is no immunity against future attacks of TD.

There are four principal bacterial microorganisms in most high-risk areas, which are Enterotoxigenic Escherichia coli (ETEC), Shigella species, Salmonella species and Campylobacter. Common viruses that cause TD are astrovirus, norovirus and rotavirus. Giardia intestinalis is the most common parasitic source while Cryptosporidium and Entamoeba histolytica can also cause TD. To answer the most common cause of TD, this will depend on the region as it varies by region although the source of infection is rarely identified in less severe cases.

Signs and symptoms of TD are loose or watery stools 4-5 times per day for 2-4 days, abdominal cramps, nausea, vomiting, fever, bloating and fatigue. Symptoms may continue for up to 10 days even after returning from the travelled destinations. Children tend to have more severe and longer diarrhoea than other travellers. Most cases are considered mild but it may be severe for some people. 60% of cases are watery diarrhoea with 3 to 5% of travellers with chronic diarrhoea or dysentery.

Symptoms in general do get better without needing specific treatments as most are mild cases. Mild cases are defined as episodes of diarrhoea that are infrequent and do not disrupt daily activities. For mild cases, getting enough rest and making sure to get hydrated throughout the day is sufficient. Rehydrating drinks must be prepared using safe water. Drinking oral rehydration salt (ORS) solutions can further help ensure hydration level is at optimal. If diarrhoea does disrupt a person’s day, they may want to consider taking antidiarrheal medicine that can be obtained from pharmacy or doctor’s visit. These medicines are not recommended for children below 12 and it is worth noting that it can cause constipation when taken in excess. Some medication may take 1 hour or more to work before diarrhoea can get better.

Self-treatment such as drinking plenty of clear fluid or ORS solution and taking antidiarrheal medication should only be done when there are no signs of severe or dangerous diarrhoea. Danger signs include high grade fever, severe stomach pain, continuous vomiting, unable to continue with normal daily life activities, more than 6 episodes of diarrhoea in the past 24 hours and presence of blood or slime in stool. When there are any of the danger signs presented, patients should not take anti-antidiarrheal medications and should get immediate medical advice.

No one want to travel and be back home with diarrhoea, right? Thus, it is best for travellers to take preventative measures to prevent TD. Below are what can be done to avoid TD:

Always wash hands with soap before eating, handling food and after using the toilet.
Boil any drinking water when in doubt of the cleanliness.
Drink bottled water and ensure the seal is in place before drinking it.
Avoid eating uncooked vegetables such as salads
Pell all fruits and clean with clean water before eating.
Do make sure meat, poultry, fish and seafood are thoroughly cooked and eaten hot whenever possible.
Try to eat early when served at a buffet.
Avoid ready-to-eat food from roadside vendors.
Bismuth subsalicylate (BBS) may be considered but may not be for everyone as it can interact with other medicines and cause blackened stool or tongue.

It can be concluded that Travelers diarrhoea is common among travellers, especially when going to certain places. This disease should not scare a person from going to places. Taking preventative measures can indeed help to reduce risk for Travelers diarrhoea and can be very helpful in preventing those at vulnerable of having the disease. While in most cases it is considered mild, warning signs should not be taken lightly.