Travel Bugs: Sicknesses Abroad

When travelling abroad, you may be exposed to a range of diseases and infections that are uncommon in your home country. These can include insect-borne diseases like malaria, Zika, and dengue fever; food- and waterborne illnesses like travellers' diarrhoea; and infections spread through animal contact, such as rabies and herpes B. In some cases, symptoms may not appear until after your return home, so it's important to be vigilant about your health both during and after your trip.

Mosquito-borne diseases, e.g. malaria, dengue fever, yellow fever

Mosquito-borne diseases are a serious concern for travellers, with mosquitoes acting as vectors for several severe illnesses, including malaria, dengue fever, and yellow fever. These diseases are prevalent in tropical and subtropical regions, and travellers must be cautious to avoid contracting them.

Malaria is caused by a parasite transmitted to humans through the bites of infected mosquitoes. The parasite infects red blood cells, leading to symptoms such as fever, chills, and anaemia. In severe cases, malaria can cause organ failure and even death. It is recommended that travellers to malaria-endemic areas take antimalarial medications and use insect repellent to prevent mosquito bites.

Dengue fever is another mosquito-borne disease that has become a global health concern. The dengue virus, transmitted by the Aedes aegypti mosquito, can cause high fever, severe headaches, and joint pain. In some cases, dengue fever can lead to a potentially fatal complication called severe dengue, characterised by severe abdominal pain, persistent vomiting, and difficulty breathing. There is no specific treatment for dengue fever, and prevention through mosquito bite avoidance is crucial.

Yellow fever is an acute viral haemorrhagic disease transmitted by infected Aedes and Haemagogus mosquitoes. The disease is endemic in 34 countries in Africa and 13 countries in Central and South America. Symptoms of yellow fever include fever, muscle pain, headache, nausea, and vomiting. In some cases, a small percentage of patients enter a second, more toxic phase, leading to jaundice, dark urine, and abdominal pain. Yellow fever can be prevented by a safe and affordable vaccine that provides life-long protection with a single dose.

It is essential for travellers to be aware of the risks associated with mosquito-borne diseases and to take the necessary precautions. This includes using insect repellent, wearing long-sleeved clothing, and sleeping under mosquito nets. Additionally, travellers should consult a healthcare professional before their trip to determine if any vaccinations or medications are recommended or required for their destination.

Food and water-borne infections, e.g. cholera, hepatitis A, traveller's diarrhoea

Food and water-borne infections are a common issue for travellers, with one in three travellers falling ill due to contaminated food and water. The most common food and water-borne infection is travellers' diarrhoea (TD). However, travellers may also contract cholera, hepatitis A, typhoid, giardia, E. coli, dysentery, salmonella, shigellosis, or amoebiasis.

Cholera

Cholera is a bacterial disease usually spread through contaminated water. It causes severe diarrhoea and dehydration, which can be fatal within hours if left untreated. The risk of cholera is higher in areas with poor sanitation, such as refugee camps, impoverished countries, and areas affected by famine, war, or natural disasters.

To prevent cholera, travellers should:

• Wash their hands with soap and water frequently, especially after using the toilet and before handling food.
• Drink only safe water, including bottled water or water that has been boiled or disinfected.
• Avoid ice in drinks unless it is made from safe water.
• Eat food that is completely cooked and hot, avoiding street food if possible.
• Stick to fruits and vegetables that can be peeled, such as bananas, oranges, and avocados.
• Avoid raw or undercooked seafood, shellfish, meat, and eggs.

An oral cholera vaccine is available for travellers, but most travellers do not require it as the risk of illness is very low.

Hepatitis A

Hepatitis A is a subtype of the hepatitis virus transmitted through contaminated water and food. It causes jaundice and liver inflammation, affecting liver function temporarily. Hepatitis A is not fatal and usually goes away on its own.

To prevent hepatitis A, travellers should:

• Get vaccinated, especially if travelling to high-risk areas.
• Wash hands frequently, especially after using the bathroom and before handling food.
• Drink only pasteurised milk.
• Wash raw fruits and vegetables thoroughly.
• Avoid eating food at room temperature; consume hot foods instead.
• Avoid raw or undercooked meat, rare meat, and runny eggs.
• Stay away from street food.

Travellers' Diarrhoea (TD)

TD is a common illness for travellers, affecting up to 50% of travellers to developing countries. It is usually caused by consuming contaminated food and water.

To prevent TD, travellers should:

• Take antibiotics or other chemical preparations preventatively if travelling to high-risk destinations.
• Consume products containing probiotics.
• Sleep well and eat healthily before travelling.
• Wash hands frequently with boiled or safe water before eating.
• Drink water from sealed containers, preferably carbonated.
• Treat water with a filtering system or disinfectant agent if its safety is uncertain.
• Avoid ice in drinks.
• Avoid buying food from street vendors or outlets with poor hygiene practices.
• Boil unpasteurised milk before consumption.
• Eat only thoroughly cooked food that has not been kept at room temperature for several hours.
• Peel all fruit and raw vegetables, and avoid fruit with damaged skins.
• Avoid salads, raw or undercooked shellfish, and dishes containing raw or undercooked eggs, poultry, or meat.

Tick-borne illnesses, e.g. Lyme disease, tick-borne encephalitis

When travelling abroad, it is important to be aware of the potential health risks, especially when it comes to tick-borne illnesses such as Lyme disease and tick-borne encephalitis (TBE). Ticks are small arachnids that feed on the blood of animals and occasionally bite humans. While ticks themselves do not cause disease, they can carry and transmit pathogens, such as viruses and bacteria, that can lead to serious illnesses.

Lyme disease is a well-known tick-borne illness caused by the bacterium Borrelia burgdorferi. It is transmitted to humans through the bite of infected ticks, particularly the Ixodes ricinus tick in Europe. Lyme disease is prevalent in many parts of the world, including North America, Europe, and Asia. The symptoms of Lyme disease can include a characteristic bull's-eye rash, fever, headache, fatigue, and muscle and joint pain. If left untreated, Lyme disease can lead to more severe complications, including neurological problems and heart issues.

Tick-borne encephalitis (TBE) is another serious tick-borne illness caused by a virus that infects the brain. TBE is transmitted through the bite of infected ticks, mainly in Europe and Asia. The highest number of cases are reported in Eastern Europe and Russia. Similar to Lyme disease, TBE can cause initial symptoms such as fever, headache, fatigue, and nausea. In more severe cases, TBE can lead to encephalitis (brain inflammation), meningitis, myelitis, and cranial neuritis. The death rate for TBE is about 1%, and many patients experience long-term complications, primarily neuropsychiatric issues.

To protect yourself from tick-borne illnesses while travelling, it is important to take preventive measures. This includes wearing protective clothing, using insect repellents, and avoiding areas with high grass and leaf litter where ticks are commonly found. Additionally, it is crucial to check your body for ticks regularly and remove them as soon as possible. If you develop any symptoms or notice a bull's-eye rash, seek medical attention promptly.

For travellers at high risk of exposure to TBE, vaccination is recommended. The TBE vaccine is safe and effective in preventing infection. Consulting with a healthcare professional or local immunisation services before travelling to TBE-endemic areas can provide personalised advice and recommendations.

Viral infections, e.g. avian flu, Zika virus, COVID-19

Viral infections are a common concern for travellers, and it is important to be aware of the risks and how to prevent them. Avian flu, Zika virus, and COVID-19 are all viral infections that have been associated with travel and can be brought back from abroad. Here is some detailed information about each:

Avian Flu

Avian influenza, or bird flu, is a family of avian viruses that are contagious among birds. Some strains of avian flu viruses have been known to infect humans as well. The risk of human infection is higher in certain regions, particularly those with close contact between people and poultry, such as in live bird markets or areas with poor sanitation. Symptoms of avian flu in humans can include fever, cough, sore throat, muscle aches, conjunctivitis, and in more severe cases, pneumonia and multi-organ failure. The incubation period is usually 2 to 8 days, and the virus can be transmitted through respiratory droplets or contact with infected surfaces.

To prevent avian flu when travelling, it is important to avoid close contact with live poultry or birds, especially in areas with known outbreaks. Cooking poultry and eggs thoroughly can also reduce the risk of infection. Good hygiene practices, such as frequent handwashing, can further lower the chances of infection.

Zika Virus

Zika virus is primarily spread through the bite of infected Aedes aegypti mosquitoes. These mosquitoes are most commonly found in tropical and subtropical regions, including parts of the Americas, Asia, and the Pacific. Symptoms of Zika virus infection are often mild and may include fever, rash, joint pain, conjunctivitis, and headache. However, Zika virus infection during pregnancy can cause severe birth defects, such as microcephaly.

To prevent Zika virus infection when travelling, it is crucial to take measures to avoid mosquito bites. This includes using insect repellent, wearing long-sleeved shirts and long pants, and staying in places with air conditioning or window and door screens. Using mosquito nets while sleeping and removing potential mosquito breeding sites, such as standing water, can also help reduce the risk of infection.

COVID-19

COVID-19 is a respiratory illness caused by the SARS-CoV-2 virus. It has been a major concern for travellers in recent years due to its highly contagious nature and global impact. COVID-19 can be spread through respiratory droplets produced when an infected person coughs, sneezes, or talks. It can also be transmitted by touching surfaces contaminated with the virus and then touching one's mouth, nose, or eyes. Symptoms of COVID-19 can range from mild to severe and include fever, cough, shortness of breath, loss of taste or smell, fatigue, and headache.

To prevent COVID-19 infection when travelling, it is essential to follow local guidelines and public health measures. This includes wearing masks, maintaining physical distance from others, and practising good hand hygiene. Staying informed about the COVID-19 situation in your destination and following any travel advisories or restrictions is also crucial. Getting vaccinated and boosted against COVID-19 is one of the best ways to protect yourself and reduce the risk of severe illness.

Sexually transmitted infections, e.g. HIV, other STIs

Sexually transmitted infections (STIs) are a major cause of acute illness, infertility, long-term disability, and death, with severe medical and psychological consequences for millions of men, women, and children. STIs are spread from person to person through sexual activity, including anal, vaginal, or oral sex. They are caused by bacteria, parasites, and viruses.

Chlamydia is a common STI that can cause infection in both women and men. It is easily treated and cured, but if left untreated, it can make it difficult for women to get pregnant. Untreated chlamydia may also increase a person's chances of getting or transmitting HIV.

Genital herpes is another common STI, but most people who have it don't know they are infected. There is currently no cure for genital herpes, but there are treatments available to manage the symptoms.

Gonorrhea is a common and treatable STI that can cause infection in the genitals, rectum, mouth, and throat. Untreated gonorrhea can increase a person's chance of getting or transmitting HIV.

Human papillomavirus (HPV) is the most common STI in the United States, but most people with HPV have no symptoms. HPV can cause serious health effects, such as cervical cancer and anal cancer, and there is a higher prevalence of both among people with HIV. A vaccine is available to prevent HPV infection.

Syphilis is an STI that can have very serious health consequences when left untreated. However, it is simple to cure with the right treatment.

Hepatitis A, hepatitis B, and hepatitis C can also be transmitted through sexual contact and pose health risks to people with HIV. Vaccines are available for hepatitis A and hepatitis B, but not for hepatitis C.

HIV (Human Immunodeficiency Virus) is a serious STI that can lead to AIDS (Acquired Immunodeficiency Syndrome). HIV can be prevented and managed through medication, such as antiretroviral therapy (ART) and pre-exposure prophylaxis (PrEP).

To protect yourself from STIs when traveling abroad, it is important to practice safe sex. This includes using condoms consistently and correctly during vaginal, anal, and oral sex. It is also recommended to get vaccinated for hepatitis A and hepatitis B before traveling, as these viruses can be spread through sexual contact. If you are concerned about HIV, consult your healthcare provider about PrEP or post-exposure prophylaxis (PEP).

Additionally, it is important to be aware of the signs and symptoms of STIs, as many of them may not cause any noticeable symptoms. Some possible symptoms include pain when urinating or having sex, discharge from the vagina, penis, or anus, unexplained rashes, sores, or ulcers on the skin, genitals, or throat, and jaundice (yellowing of the skin and eyes). If you experience any of these symptoms or engage in risky behaviors, seek medical attention promptly and get tested for STIs.

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