A Yellow Fever vaccination certificate is required only for travellers coming from, or in transit through, infected countries. The vaccination requirement is imposed by this country for protection against the introduction of Yellow Fever since the vector Aëdes aegypti is present in its territory.
The following countries are considered infected:
AFRICA - Angola, Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Republic of the Congo, Democratic Republic of the Congo, Côte d'Ivoire, Equatorial Guinea, Ethiopia, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Liberia, Mali, Mauritania, Niger, Nigeria, Rwanda, São Tomé and Príncipe, Senegal, Sierra Leone, Somalia, Sudan, Tanzania, Togo, Uganda.
AMERICAS - Argentina, Bolivia, Brazil, Colombia, Ecuador, Guyana, French Guiana, Panama, Paraguay, Peru, Suriname, Trinidad and Tobago, Venezuela.
Note: A vaccination certificate is required for children over one year of age.
Your trip is a good occasion for a reminder to keep your routine immunizations updated; more than 80% of adults in industrialized countries have not maintained their immunization status. The following vaccinations are recommended for your protection and to prevent the spread of infectious diseases.
Tetanus, Diphtheria, Pertussis, Measles, Mumps, Rubella, Polio should be reviewed and updated if necessary. Note: Many of these vaccine preventable illnesses are making a resurgence due to non-vaccination, incomplete vaccination, and waning immunity. It is important to keep your routine immunizations up-to-date.
Seasonal influenza vaccination is recommended for all travellers over 6 months of age, especially for children, pregnant women, persons over 65, and those with chronic health conditions such as asthma, diabetes, lung disease, heart disease, immune-suppressive disorders, and organ transplant recipients. Note: In the northern hemisphere the flu season typically runs from November to April and from April to October in the southern hemisphere. If the flu vaccine is not available at the time of departure, contact your doctor or travel health clinic regarding influenza anti-viral protection.
Pneumococcal vaccine is recommended for persons over the age of 65 and persons of any age suffering from cardiovascular disease, diabetes, renal disorders, liver diseases, sickle cell disease, asplenia, or immuno-suppressive disorders.
Tonga has reported cases of Measles. Large numbers were reported in Nuku'alofa. For the latest information on Measles outbreaks please go to: ProMED-mail. Measles update (13). ProMED-mail 2014; March 30: 20140330.2367378. <www.promedmail.org>. Accessed March 31, 2014.
The Hepatitis A virus (HAV) is primarily transmitted from person to person via the fecal-oral route and through contaminated water and food - such as shellfish, and uncooked vegetables or fruit prepared by infected food handlers.
Risk: The virus is present worldwide, but the level of prevalence depends on local sanitary conditions. HAV circulates widely in populations living in areas with poor hygiene infrastructure. In these areas, persons usually acquire the virus during childhood when the illness is asymptomatic (but still infective to others) or mild, and end up developing full immunity. Large outbreaks in these countries are rare. In contrast, a large number of non-immune persons are found in highly industrialized countries where community wide outbreaks can occur when proper food handling or good sanitation practices are not maintained including in daycare centres, prisons, or mass gatherings.
Symptoms: In many cases, the infection is asymptomatic (persons do not exhibit symptoms). Those with symptoms will usually get ill between 15 to 50 days after becoming infected. Symptoms include malaise, sudden onset of fever, nausea, abdominal pain, and jaundice after a few days. The illness can range from mild to severe lasting from one to two weeks or for several months. Severe cases can be fatal especially in older persons. Most infections are asymptomatic in children under six years of age, but infants and children can continue to shed the virus for up to six months after being infected, spreading the infection to others. Many countries are now including vaccination against Hepatitis A in their childhood vaccination schedules.
Prevention: Practice good personal hygiene, including washing your hands frequently and thoroughly, drink boiled or bottled water, eat well cooked foods, and peel your own fruits.
All non-immune persons, especially travellers, should be vaccinated. Two vaccines are available for persons over one year of age. Two doses are needed for full protection (the second dose is given 6 to 12 months after the first dose (HAVRIX) or 6 to 18 months after the first dose (VAQTA). TWINRIX is a combined vaccine against Hepatitis A and B. It is available for persons over 18 years of age. Three doses are needed for full protection. The second dose is given 1 month after the first, and the third 6 months later. For an accelerated schedule four doses are needed at 0, 7, 21, 31 days and the last dose 12 months later.
The Hepatitis B virus (HBV) can cause acute and chronic liver infections. It is transmitted through infected blood products, unprotected sex, infected items such as needles, razor blades, dental or medical equipment, unscreened blood transfusions, or from mother to child at birth.
Risk: The virus is present worldwide, but some populations in sub-Saharan Africa, Southeast Asia, Eastern Europe, and the Middle East, as well as indigenous communities are chronic Hepatitis B carriers. Travellers getting tattoos or piercing abroad, using drugs intravenously, sharing needles and razor blades, undergoing dental or medical procedures, or having unprotected sex are at risk.
Symptoms: In many cases, the infection is asymptomatic (persons do not exhibit symptoms). Those with symptoms will usually get ill between 30 days and 6 months after becoming infected. Symptoms include fatigue, malaise, nausea, abdominal pain, dark urine, and jaundice. The illness can last several weeks and some adults can become chronic carriers after being infected. Hepatitis B can cause chronic liver infections, cirrhosis of the liver, or liver cancer. Most infections are asymptomatic in children under five years of age but they can become chronic carriers. Many countries are now including vaccination against Hepatitis B in their childhood vaccination schedules. Treatment includes supportive care of symptoms. Some cases of chronic Hepatitis B can be treated with antiretroviral drugs.
Prevention: Avoid getting new piercings or tattoos on your trip and do not share needles or razor blades. If you need medical or dental care abroad, ensure that it is done by a reputable facility. Always practice safe sex.
Vaccination is recommended for travellers on working assignments in the health care field such as physicians, nurses, laboratory technicians, dentists, or for those working in close contact with the local population such as teachers, aid workers, and missionaries.
Immunization against Hepatitis B consists of three doses. The second dose is given 1 month after the first and the third dose 6 months later (ENGERIX B or RECOMBIVAX). The ENGERIX B vaccine can be given in a 4 dose accelerated schedule at 0, 1, 2 months followed by the last dose after 12 months of the first dose. TWINRIX is a vaccine against Hepatitis A and B. It is available for persons over 18 years of age. Three doses are needed for full protection. The second dose is given 1 month after the first, and the third 6 months later. For an accelerated schedule four doses are needed at 0, 7, 21, 31 days and the last dose 12 months later.
The recommendations for vaccinations outlined above are intended as guidelines only. Your immunization needs depend on your health status, previous immunizations received, and your travel itinerary. Seek further advice from your doctor or travel health clinic.
Outdoor air pollution (a mix of chemicals, particulate matter, and biological materials that react with each other) contributes to breathing problems, chronic diseases, increased hospitalization, and premature mortality.
Risk: No matter where you travel, you will not be able to escape air pollution since cities and rural areas worldwide are affected by air pollution. Exposure and concentration of pollutants can adversely affect your health. When planning your trip, consider your health status, age, destination, length of trip and season to help you mitigate the effects of air pollution.
Symptoms: Short term symptoms resulting from exposure to air pollution include itchy eyes, nose and throat, wheezing, coughing, shortness of breath, chest pain, headaches, nausea, and upper respiratory infections (bronchitis and pneumonia). It also exacerbates asthma and emphysema. Long term effects include lung cancer, cardiovascular disease, chronic respiratory illness, and developing allergies. Air pollution is also associated with heart attacks and strokes.
Prevention: Comply with air pollution advisories (ask around and observe what locals are doing) and avoid strenuous activity. If you have asthma or chronic obstructive pulmonary disease (COPD), carry an inhaler, antibiotic, and oral steroid (consult your doctor to see what is best for you). It is recommended that older travellers get a physical exam that includes a stress and lung capacity test prior to departure. Newborns and young children should minimize exposure as much as possible or consider not travelling to areas with poor air quality. Ask your medical practitioner if a face mask is advisable for you.
>> For city and country air pollution levels, see the World Health Organization.
Chikungunya is a viral infection transmitted to humans through the bite of infected daytime biting female mosquitos. The Aëdes aegypti mosquito is the primary vector, but the Aëdes albopictus mosquito is also responsible for transmitting the CHIK virus belonging to the Togaviridae family.
Risk: Travellers going to parts of the Caribbean, sub-Saharan Africa, southeast Asia, and the Indian subcontinent are at risk, especially during the rainy season. The mosquitos usually bite early morning and late afternoon and are typically found in and around domestic dwellings. Some mosquitos carrying the Chikungunya virus in Africa also live in forested areas. Monkeys and other wild animals are also believed to be reservoirs for the virus. Isolated cases of imported Chikungunya have occurred in the Americas and Europe.
Symptoms: The initial symptoms of sudden fever and sever muscle and joint pain usually appear between 3 to 7 days and sometimes until 12 days after the bite. Not everyone exhibits symptoms and the infection may go undetected. Other symptoms include headache, fatigue nausea, vomiting, and a rash. Although most patients fully recover, chronic joint pain may last for several weeks or months. Other persistent problems may include eye, gastrointestinal, neurological, and heart complications. Sometimes Chikungunya is misdiagnosed in areas where Dengue also occurs.
Persons with chronic health conditions, compromised immune systems, newborns, the elderly are at risk of developing complications with this infection. Chikungunya is rarely fatal.
Prevention: Travellers should take measures to prevent mosquito bites both indoors and outdoors, especially during the daytime. Insect-bite prevention measures include applying a DEET-containing repellent to exposed skin, applying permethrin spray (or solution) to clothing and gear, wearing long sleeves and pants, getting rid of water containers around dwellings and ensuring that door and window screens work properly. There is no preventive vaccine against Chikungunya.
Tonga has reported cases of Chikungunya nationally. For the latest information on Chikungunya fever outbreaks please go to: ProMED-mail. Chikungunya (27): Tonga, New Caledonia ex Tonga. ProMED-mail 2014; April 17: 20140417.2409660. <www.promedmail.org>. Accessed April 21, 2014.
The health risks listed below are of interest to travellers who undertake special activities like adventure travel or ecotourism, long term travellers, visiting friends and family, or those on work assignments abroad. We update our travel health information daily with any new confirmed outbreaks so check back here before your trip for updates. Please note that some infectious diseases are not reported or under reported, preventing us from giving you the full picture of the health risk.
Parasitic worms are organisms that can live and replicate in the gastro-intestinal system. These soil-transmitted helminths (hookworms, roundworms, whipworms) are transmitted through the fecal-oral route as a result of poor sanitary practices. The most common infections that can affect travellers are Ascariasis, Hookworm, and Trichuriasis which are Neglected Tropical Diseases (NTDs)*.
Risk: Travellers can get ill when worm eggs are ingested by:
Ascariasis: The infection is caused by Ascaris lumbricoides roundworm and is typically found in tropical and sub-tropical areas. Persons with light infections may not exhibit any symptoms. Those who develop symptoms start with a persistent cough, wheezing, shortness within 1 week of getting infected as a result of larvae migrating to the lungs and throat. The second set of symptoms, including abdominal pain, nausea, vomiting, diarrhea, bloody or worm in stools, fatigue, weight loss appear a few weeks (up to 2 or 3 months) later as the roundworms become adults and the females lay eggs which are shed through feces. The parasite can live in humans for up to 2 years. Children are particularly affected by this illness because they tend to play in and eat dirt. Treatment includes taking anthelmintic drugs.
Hookworm | Ancyclostomiasis: This intestinal infection is primarily caused by Necator americanus, followed by Ancylostoma duodenale, and to a lesser extent by Ancylostoma ceylanicum nematodes typically found in tropical and sub-tropical areas. Persons with light infections may not exhibit any symptoms. Those who develop symptoms first get a skin rash where the larvae penetrate the skin. Abdominal pain, diarrhea, loss of appetite, weight loss, and fatigue occur as the migrated larvae grow into adults and mate in the gastro-intestinal system. The eggs produced by the females are shed through feces. Note that the Ancylostoma duodenale hookworm can also be acquired by ingesting soil or sand through dirty hands or unwashed fruits and vegetables.A typical sign of this infection is anemia (iron deficiency). Treatment includes taking anthelmintic drugs.
Trichuriasis: The infection in humans is caused by the Trichuris trichuria whipworm and occurs worldwide, especially in areas with no proper sewage disposal. Persons with light infections may not exhibit any symptoms. Those who exhibit symptoms have diarrhea, containing blood, mucous, and water as a result of the swallowed eggs hatching in the caecum, the pouch-like area of the large intestine, and the larvae migrate to the lining the colon to grow into adulthood and mate. The eggs produced by the females are shed through feces. Severe cases include abdominal pain, chronic diarrhea, and rectal prolapse. Whipworms can live in humans for years. Children are particularly affected by this illness because they tend to play in and eat dirt. Treatment includes taking anthelmintic drugs.
* Neglected Tropical Diseases are chronic infections that are typically endemic in low income countries. They prevent affected adults and children from going to school, working, or fully participating in community life, contributing to stigma and the cycle of poverty.
Lymphatic Filariasis, also known as Elephantiasis, is a parasitic infection caused by the Wuchereria bancrofti, Brugia malayi, and Brugia timori nematode worms transmitted to humans through the bite of infected Aedes, Culex, Anopheles, and Mansonia mosquitoes. The disease targets the body's lymphatic system. The infective microscopic larvae (microfilariae) develop in the vector mosquitoes and are injected into humans through a blood meal. In the human host, they reproduce and mature over a period of one year and live in the body for approximately 4 to 6 years. The larvae hatched in humans are ingested by feeding mosquitoes who pass the infection on to another person, continuing the infectious cycle. Lymphatic Filariasis is a Neglected Tropical Disease (NTD)*.
Risk: Lymphatic Filariasis is present in Africa, Central and South America, South Asia, and the Pacific Islands. There is a greater risk for long term travellers visiting endemic areas. Persons on long term work assignments like humanitarian workers, missionaries, and military personnel are also at risk.
Symptoms: The infection is typically characterized by extreme swelling of limbs or genitals. The majority of cases are asymptomatic (persons do not exhibit symptoms) although the worms can damage kidneys and lymph nodes over a long period of time without a person showing external symptoms. A severe infection, which may not show up for years, causes swelling in the genitals, breasts, arms and legs and may progress to lung disease. Treatment includes taking the anthelmintic drugs diethylcarbamazine (DEC) and albendazole.
Prevention: Travellers should take precautions against mosquito bites by wearing light coloured clothing, using DEET-containing repellent on exposed skin, applying a permethrin spray (or solution) to clothing and gear, and sleeping under a permethrin-treated bed net. There is no preventive medication or vaccine against Lymphatic Filariasis.
>> For Lymphatic Filariasis images, life cycle, and distribution maps, see Infection Landscapes.
* Neglected Tropical Diseases are chronic infections that are typically endemic in low income countries. They prevent affected adults and children from going to school, working, or fully participating in community life, contributing to stigma and the cycle of poverty.
Tuberculosis (TB) is an airbone bacterial infection caused by Mycobacterium tuberculosis. TB can be acquired by breathing contaminated air droplets coughed or sneezed by a person nearby who has active Tuberculosis. Humans can also get ill with TB by ingesting unpasteurized milk products contaminated with Mycobacterium bovis, also known as Bovine Tuberculosis. The most common form of the infection is pulmonary TB which affects the lungs. In some cases, the bacteria can also attack the lymphatic system, central nervous system, urogenital area, joints, and bones.
Risk: Tuberculosis occurs worldwide and commonly spreads in cramped, overcrowded conditions. There is no evidence that pulmonary TB is more easily transmitted in airplanes or other forms of public transportation. Travellers with a compromised immune system, long-term travellers, and those visiting friends and relatives (VFR travellers) in areas where Tuberculosis is endemic are at greater risk. Humanitarian and healthcare personnel working in communities with active TB are also at increased risk. Persons with active TB should not travel.
Symptoms: Persons with active TB have symptoms which include excessive coughing (sometimes with blood), chest pain, general weakness, lack of appetite, weight loss, swollen lymph glands, fever, chills, and night sweats. It can be misdiagnosed for bronchitis or pneumonia. If untreated, active TB can lead to fatalities.
The majority of persons with the illness (90% to 95%) have latent TB infection (LTBI) and do not exhibit any symptoms. The bacteria can remain inactive for many years and the chance of developing active TB diminishes over time.
Tuberculosis treatment involves taking antibiotics for a minimum of 6 months. Drug-resistant TB is a major concern as an increasing number of people are no longer able to be treated with previously effective drugs. Due to misuse of antibiotic therapies, patients can develop multi-drug resistant Tuberculosis (MDR TB). When a second line of antibiotics fail to cure the multi-drug resistant infection, it is known as extensively drug-resistant Tuberculosis (XDR TB).
Prevention: Avoid exposure to people known to who have active Tuberculosis and only consume pasteurized milk products. Travellers at higher risk should have a pre-departure tuberculin skin test (TST) and be re-tested upon their return home. Those at increased risk should also consult their healthcare provider to determine if the Bacillus Calmette-Guérin (BCG) vaccine is recommended.
Drinking water is chlorinated and has no ill effect on the local population. However, some strains of E. coli (naturally occurring bacteria found in your gastro-intestinal system) may be present in very small concentrations in the local water supply. Some local strains are different than those that you may be used to, and may cause diarrhea in travellers since immunity is not developed as a result of short-term exposure. Using bottled water for the first few weeks will help you adjust and decrease the chance of traveller's diarrhea.
Milk is pasteurized and safe to drink. Butter, cheese, yoghurt, and ice cream are safe.
Local meat, poultry, seafood, vegetables, and fruits are safe to eat.
Globalized food production and shipping are making it harder for consumers to know if their food and water is safe. Travellers should be aware that food and water contamination not only occurs through improper food handling or poor hygiene practices. Air, soil, and water pollution resulting from heavy metals, dioxins, pesticides, agro-chemicals, and drugs given to food-production animals, occurs worldwide. IAMAT recommends eating locally sourced foods from reputable growers as much as possible. We will post any new information on outbreaks resulting from environmental contamination on this page. Don’t forget to consult our website before your trip!
Being prepared is important to preventing allergic reactions or anaphylactic shock during your trip.
The term Traveller's Diarrhea is used to describe gastro-intestinal infections affecting travellers caused by ingesting bacteria, viruses, and protozoa. These micro-organisms are found worldwide and are typically transmitted from person to person via the fecal-oral route – an infected person who does not practice proper hand or body hygiene passes on the infection to another person when handling food and water. Traveller's Diarrhea is the most common illness among travellers.
Risk: Traveller’s Diarrhea can happen when:
Prevention: The golden rule to prevent gastro-intestinal infections is: Boil it, Cook it, Peel it, or Forget it! However, it’s not just about what you eat, it’s also important to consider where you eat. It’s not always easy to know if a restaurant or food vendor follows proper food handling and hygienic practices (properly cleaning cutting boards, utensils, sink to wash hands, refrigeration). Be cautious of food that has been stored uncovered, has been improperly refrigerated, or has been standing out for a long time, such as buffets.
More information on Food and Water Safety:
>> How To Prevent Traveller's Diarrhea [PDF]
>> How To Prevent Food and Water Illnesses [PDF]
>> How To Prevent Illness by Washing Your Hands [PDF]
>> 24 World Food and Climate Charts
>> Guide to Healthy Travel
Approximately 85% of Traveller’s Diarrhea is caused by bacteria. Symptoms involving bacterial infections generally appear within hours of eating contaminated food or water and can last 3 to 7 days. Typical symptoms include diarrhea, abdominal pain, nausea, general weakness, headache, low fever, and possible vomiting. Severe cases can cause dehydration.
The following are common bacteria causing food and water illnesses in travellers:
Enterotoxigenic Escherichia coli (ETEC) – Commonly known as ‘E. coli’ and responsible for the majority of Traveller’s Diarrhea cases. The illness is associated with contaminated food and water. Symptoms appear 1 to 3 days after infection. Treatment includes supportive care of symptoms and in severe cases antibiotics are prescribed.
Campylobacter jejuni– Associated with contaminated water, undercooked poultry, unpasteurized milk. Symptoms appear 1 to 7 days after being infected and can last 2 to 3 weeks without treatment. Some patients also have bloody diarrhea. Post-infection complications can lead to Guillain-Barré Syndrome, where the immune system attacks the nerves and causes paralysis, or irritable bowel syndrome. Treatment includes antibiotics.
Salmonella enteritidis – Associated with eggs, poultry, meat, raw fruits and vegetables. Symptoms usually appear 1 to 3 days after infection and can last up to 7 to 14 days. Infected persons can become asymptomatic carriers and shed the bacteria for weeks or months, becoming the source of infection for others through poor hygiene practices. Treatment includes supportive care of symptoms. Salmonella typhi is the cause of Typhoid Fever.
Shigellosis – Associated with contaminated food and water and caused by one of four Shigella species that spreads as a result of unsanitary conditions, contaminated food and water, and overcrowded living conditions. Symptoms usually last 4 to 7 days. The illness may progress to bloody diarrhea with mucous and the constant urge to pass stools. Shigella bacteria can be shed from your gastro-intestinal system for up to 3 months after symptoms disappear. Treatment includes antibiotics.
Vibrio cholera, Vibrio parahaemolyliticus, Vibrio vulnificus – Associated with contaminated water, raw or undercooked fish and shellfish and causes Cholera, an acute gastro-intestinal infection. Risk to travellers is low and vaccination is advised only for medical and rescue personnel working in endemic areas. The infection can lead to severe dehydration and death in undernourished persons or those with compromised immune systems or kidneys. Vibrio vulnificus has caused septicemia (blood poisoning) in persons with liver disorders.
Approximately 5% of Traveller’s Diarrhea is caused by viruses. A person can become ill when touching contaminated surfaces with the virus (railings, door knobs), shaking hands, or coming into close contact with an infected person and then touching your mouth and eyes.
The most common viruses causing food and water illnesses in travellers are:
Norovirus – Associated with outbreaks at large gatherings or on cruise ships. The illness is also caused by contaminated water and foods like salads, clams, and oysters. Symptoms can appear 10 hours to 2 days after infection and include nausea, vomiting, abdominal pain, diarrhea, and sometimes fever and dehydration. The illness usually last 1 to 4 days and treatment includes supportive care of symptoms.
Rotavirus – Particularly affects children less than 5 years old and is also associated with contaminated food and water. Symptoms appear 1 to 3 days after being infected and include vomiting, diarrhea, fever, abdominal pain, and headache. Dehydration and body limpness are characteristics of this illness which typically lasts 4 to 8 days. Vaccination is recommended for children. Treatment includes supportive care of symptoms for both children and adults.
Approximately 10% of Traveller’s Diarrhea is caused by protozoa. In addition to contaminated food and water, these one-celled microscopic organisms are also transmitted to humans by swallowing contaminated water from lakes, rivers, fountains, ponds, and other bodies of water or accidentally swallowing soil or sand containing protozoa eggs. Typical symptoms include abdominal pain and cramps, diarrhea, bloating, nausea, lack of appetite, fatigue, headache, and light fever. Prolonged infection causes dehydration and weight loss.
The most common protozoa causing food and water illnesses in travellers are:
Amoebiasis – Caused by Entamoeba histolytica protozoa. The majority of cases are asymptomatic (persons do not exhibit symptoms). Those who do exhibit symptoms usually develop them 2 to 4 weeks after being infected. Amoebic Dysentery is the more severe form of the illness where patients develop fever and blood in their stools. In rare cases, the protozoa can cause lesions in the liver. Treatment includes taking medication belonging to the nitroimidazole family of drugs.
Cryptosporidiosis –The infection, commonly referred to as ‘Crypto’, is primarily caused by Cryptosporidium hominis protozoa. The illness is associated with contaminated food or water, including swimming pools and other water bodies. Some people are asymptomatic (do not exhibit symptoms). Those who do exhibit symptoms usually develop them 2 to 10 days after being infected. Some patients may also have a cough, recurring headache, dizziness, eye pain, and joint pain. The illness can trigger irritable bowel syndrome and inflammatory bowel diseases. Symptoms usually disappear after 1 to 2 weeks as the protozoa are shed through feces. Treatment includes anti-protozoal medication or antibiotics.
Cyclosporiasis – Caused by the Cyclospora cayetanensis protozoa and associated with fresh produce like berries and lettuce. Symptoms usually appear 2 to 7 days after infection. Some patients may develop fever after a few days. The diarrhea may come and go throughout the duration of the illness which can last from 2 to 12 weeks if untreated. The infection tends to be seasonal for reasons yet unknown and disinfecting agents like chlorine do not seem to kill the protozoa. Treatment includes taking antibiotics.
Giardiasis–Caused by Giardia intestinalis protozoa and associated with contaminated food and water. Symptoms usually appear 1-2 weeks after infection. The symptoms usually disappear 2-4 weeks later as the protozoa are shed through feces. Treatment includes taking medication belonging to the nitroimidazole family of drugs. Treatment includes taking medication belonging to the nitroimidazole family of drugs.
Another source of gastro-intestinal illness are foodborne toxins produced by bacterial spores that germinate on food – particularly meat, poultry, salads, baked goods, and dairy products – that is improperly stored or refrigerated, usually standing at room temperature for a prolonged period of time.Symptoms can appear within hours of ingesting contaminated food and include abdominal pain, diarrhea, nausea, and vomiting. The infection usually lasts 1 or 2 days and treatment includes supportive care of symptoms. Antibiotics are not recommended.
Common foodborne toxins affecting travellers include:
Clostridium perfringens – Associated with meat and poultry and is the most important agent causing food poisoning in industrialized countries. Symptoms appear within 6 to 24 hours after ingestion.
Staphylococcus aureus – Associated with creamy desserts, custards, meats, and baked goods. Enterotoxins are transmitted via unsanitary practices by infected persons. Symptoms appear within 30 minutes to 8 hours after ingestion.
Clostridium botulinum – Associated with improperly canned food, lightly preserved vegetables, salted fish, and meats. Symptoms usually appear within 12 to 48 hours and include nausea, vomiting, blurred and double vision, paralysis of respiratory and motor muscles that may progress rapidly.
Seafood and shellfish poisoning occurs as a result of eating marine food products contaminated with naturally occurring toxins in sea water. Travellers are at risk in any country as a result of the availability of these products (fresh or frozen) around the world.
The most common seafood and shellfish related illnesses in travellers are:
Ciguatera Fish Poisoning – Occurs when toxins created by dinoflagellate micro-organisms are passed up the marine food chain and bio-accumulate in large fish like barracuda, grouper, red snapper, moray eel, amberjack, parrotfish, hogfish, sturgeonfish, kingfish, coral trout, and sea bass. The toxins are not destroyed through cooking, smoking, or freezing, they are odorless and tasteless, and do not alter the appearance of the fish. For information on symptoms and prevention, see Ciguatera Fish Poisoning.
Scombroid Poisoning – Results from improper handling and refrigeration of fish containing high levels of natural occurring histidine (amino acid in protein). Contamination with bacteria will convert histidine to histamine causing symptoms similar to allergic reactions, which occur very rapidly and include headache, abdominal cramps, diarrhea, itching, flushed face, dry mouth, heart palpitations, difficulty breathing. Symptoms rarely last over 8 to 12 hours. Scombroid poisoning affects fish from the Scombridae family: Tuna, mackerel, skipjack, and bonito. It can also affect other species such as herring, bluefish, sardine, anchovy, amberjack, and mahi-mahi. Treatment includes taking anti-histamines and supportive care of symptoms. Treatment in severe cases may include anti-inflammatory steroids and epinephrine related medication.
Shellfish Poisoning – Associated with the algal blooms (red tides) occurring in temperate and tropical areas. Oysters, clams, cockles, mussels, scallops, crabs, and lobsters filter or ingest toxins produced by dinoflagellates micro-organisms. There are four different illnesses associated with shellfish poisoning:
Puffer (Fugu) Fish Poisoning – Caused by a tetrodotoxin accumulating mainly in the liver, intestines and ovaries of puffer fish, ocean sunfish, globe fish, and porcupine fish. Symptoms appear between 6 and 20 hours and include nausea, abdominal pain, diarrhea, vomiting, profuse sweating, salivation, headache, hypothermia, heart palpitation. Neurological symptoms include numbness, loss of coordination, tremors, and paralysis. The illness can also cause respiratory failure and approximately 60% of patients die. Treatment involves supportive care of symptoms and may include cholinesterase inhibitors (anti-poisoning agents).
Travel is enjoyable, but there is no doubt that it can be stressful. Even if you don't have a prior history of mental illness, travel stress, mood changes, anxiety and other mental health concerns can unexpectedly affect you and potentially disrupt your trip. Studies show that psychiatric emergencies are the leading cause for air evacuations along with injuries and cardiovascular disease.
Your mental and physical health prior to, and during, a trip determines how well you will cope with travel stress. Consider the following:
Mental illness is an under recognized public health concern and travellers often have difficulty accessing adequate emergency psychiatric care abroad. While some countries are leading the way in mental healthcare and treatment, 30% of countries do not have a budget dedicated to mental health and 64% do not have any mental health legislation or it's outdated.
Accessibility to a psychiatrist varies from more than 10 per 100,000 to fewer than 1 per 300,000 people. Almost 70% of psychiatric beds are in mental hospitals rather than general hospitals or in integrated community care facilities.*
Persons with mental health concerns have the additional burden of dealing with stigma ? negative attitudes and behaviour towards their illness. Prejudice and discrimination towards mental illness may determine the type of medical care you will receive abroad.
* World Health Organization: Mental Health, Human Rights and Legislation Framework.
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