Travel Immunization

Yellow fever vaccine in Nepal is a requirement for travelers arriving from countries with a risk of yellow fever transmission, or for those who have transited through an infected area for more than 12 hours. The vaccination requirement is imposed by this country for protection against Yellow Fever since the principal mosquito vector Aedes aegypti is present in its territory. A Yellow Fever certificate is valid starting 10 days after vaccination.

Risk of Yellow Fever transmission exists in these countries:
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, Senegal, Sierra Leone, South Sudan, Sudan, Togo, Uganda.

AMERICAS – Argentina, Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Panama, Paraguay, Peru, Suriname, Trinidad and Tobago, Venezuela.

ASIA – India, Nepal.

Children: A vaccination certificate is required for children of all ages. However, Yellow Fever vaccination is not recommended for children under 9 months of age. If travel is unavoidable and the child’s physician considers vaccination unwise, ask for a letter on the physician’s own stationary explaining the reason for not vaccinating the child. Note that some countries may not honour this and the infant may be refused entry or be put under surveillance upon arrival.

Note: If your medical practitioner has advised you against the Yellow Fever vaccine for medical reasons, a vaccination waiver should be issued. Be aware that problems may arise when crossing borders and your vaccination waiver may not be honoured.

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.

Vaccination: Recommended for all travellers over 1 year of age.
There are two inactivated vaccines available in Canada and the USA, including a combined Hepatitis A and Hepatitis B vaccine. A combined Hepatitis A and Typhoid Fever vaccine is also available in Canada and Europe. Hepatitis A vaccines confer long term protection and can be given in accelerated schedules. Discuss your options with your healthcare provider if you cannot finish the series prior to your departure. Immune Globulin may be recommended for some last-minute travellers.

Typhoid Fever is a gastro-intestinal infection caused by Salmonella enterica typhi bacteria. It is transmitted from person to person – humans being the only reservoir – via the fecal-oral route where an infected or asymptomatic individual (does not exhibit symptoms) with poor hand or body hygiene passes the infection to another person when handling food and water. The bacteria multiply in the intestinal tract and can spread to the bloodstream. Paratyphoid fever, a similar illness, is caused by Salmonella enterica paratyphi A, B, and C.

Risk: The infection is endemic in many Southeast Asian countries as well as in Central and South America, the Caribbean, and Africa where there is poor water and sewage sanitation. Floods in these regions can also quickly spread the bacteria. All travellers going to endemic areas are at risk, especially long term travellers, adventure travellers, and those visiting friends or relatives in areas of poor sanitation. Note that original infection does not provide immunity to subsequent infections.

Symptoms: Usually appear 1 to 3 weeks after exposure. Depending on the virulence of the infection symptoms can range from mild to severe. The illness is characterized by extreme fatigue and increasing fever. Other symptoms include headache, lack of appetite, malaise, and an enlarged liver. Sometimes patients have diarrhea, constipation, or a rash on their trunk. Severe symptoms may appear 2 to 3 weeks after onset illness and may include intestinal hemorrhage or perforation. Some people who recover from Typhoid or Paratyphoid Fever continue to be carriers of the bacteria and can potentially infect others. Treatment includes antibiotics and supportive care of symptoms. Unfortunately, S. typhii resistance to antibiotics is increasing worldwide.

Prevention: Wash your hands frequently and thoroughly, and practice proper body hygiene. Drink purified water (boiled or untampered bottled water) and only eat well cooked foods. Use the mantra Boil it, Cook it, Peel it, or Forget it!

Vaccination: Recommended for travellers going to endemic areas.

There are two types of vaccines available; the inactivated injectable vaccine (lasting 2-3 years) and the live attenuated oral vaccine (lasting 5-7 years). Discuss your best options with your healthcare provider, including revaccination recommendations which differ in the USA and Canada. A combined Hepatitis A and Typhoid Fever vaccine is also available in Canada and Europe. Although typhoid vaccines do not provide 100% protection, they will reduce the severity of the illness. There is no vaccine available against Paratyphoid Fever.

Typhoid fever has been reported in the Saptari district.

Cholera is an acute gastro-intestinal infection caused by Vibrio cholerae bacteria. It is primarily associated with contaminated water, food, especially raw or undercooked fish and shellfish. The bacteria 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 the infection to another person when handling food and water.

Risk:  Travellers going to, or living and working in, places with inadequate sanitary conditions such as refugee camps are at greater risk. Persons with compromised immune systems, including those who have had surgery for duodenal or gastric ulcers or are on antacid therapy, and users of cannabis – smoking marijuana reduces acid secretion of the stomach – are more susceptible to cholera infection.

Symptoms: Most cases are asymptomatic (persons do not exhibit symptoms). Some have gastro-enteritis – diarrhea, vomiting, stomach cramps. Severe symptoms include watery diarrhea, vomiting, nausea, stomach pain, dehydration, dry skin and mucous membranes. If untreated, the infection can lead to severe dehydration and death in undernourished persons or those with compromised immune systems. Treatment includes taking an oral rehydration solution to rebalance electrolytes and antibiotics.

Prevention: The best protection is to avoid potentially contaminated water and food. Drink purified water and eat well cooked foods only. Use the mantra Boil it, Cook it, Peel it, or Forget it! Also wash your hands frequently and thoroughly, and practice good body hygiene.

Note that the World Health Organization announced in 1991 that Cholera vaccination certificates are no longer required by any country or territory.

Vaccination: Recommended for long term travellers, healthcare and humanitarian workers, and immunosuppressed travellers going to endemic areas, as well as travellers with reduced stomach acid production.

An inactivated oral vaccine is available in Canada and countries where Cholera may be endemic. It is not available in the USA. The vaccine does not provide 100% protection against Cholera and rapidly wanes over time so take food and water precautions, and practice good hand hygiene.

The vaccine is also licensed in Canada for protection against Enterotoxigenic E. coli (ETEC) bacteria. However, ETEC causes less than 50% Traveller’s Diarrhea cases and the vaccine does not work against other pathogens causing Traveller’s Diarrhea. Talk to your healthcare provider regarding your best prevention options.

Cholera has been reported in Kathmandu and the Rautahat district.

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. 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.

Risk: 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 provider. Always practice safe sex.

Vaccination: Hepatitis B vaccination is a routine immunization. If you haven’t been vaccinated, it 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.

There are two inactivated vaccines available in the Canada and the USA, including a combined Hepatitis A and Hepatitis B vaccine. Both types of vaccines confer long term protection and can be given in accelerated schedules. Discuss your options with your healthcare provider if you cannot finish the series prior to your departure.

Japanese Encephalitis is a viral infection caused by RNA viruses belonging to the Flavivirus genus. It is a zoonosis (an animal disease that can spread to humans) primarily transmitted by Culex mosquitoes that bite infected birds, pigs and other mammals passing the infection to humans living and working in rural areas around rice paddies and irrigation systems.

Risk: Travellers to endemic areas are at risk, especially those visiting rural areas, farms, rice fields and irrigation areas, including persons involved in outdoor recreational activities or on working assignments. Children under 15 years of age seem to particularly susceptible to the infection. Outbreaks typically occur during or shortly after the rainy season in temperate regions and year-round, with peak transmission during summer months, in tropical regions. Japanese Encephalitis is endemic in Southeast Asia.

Symptoms: The majority of cases are asymptomatic (persons do not exhibit symptoms). If a person exhibits symptoms, they usually appear between 5 to 15 days after being infected. They include fever, severe headache, vomiting, diarrhea, and general weakness. Some patients will develop neurological symptoms such as tremors, seizures (especially children), expressionless face, and sudden paralysis which can affect the respiratory system and cause bladder retention problems. Patients may also experience behavioural changes which can be misdiagnosed as psychiatric illness. Japanese Encephalitis can be fatal in 20% to 30% percent of cases and many survivors continue to have long term neurologic, psychiatric, or cognitive problems. Treatment includes supportive care of symptoms.

Prevention: Travellers should take measures to prevent mosquito bites both indoors and outdoors, especially during the evening and night time. 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.

Vaccination: Recommended for persons travelling extensively in rural areas, long term travellers, and persons on working assignments in endemic areas.

The inactivated Vero cell vaccine is available in Canada, the USA and select countries. Booster vaccination is recommended 1-2 years if you are at continued risk of exposure. Live attenuated vaccines are available in Japanese Encephalitis endemic countries where they are given as part of the childhood routine immunization schedule. Discuss your options with a healthcare provider if you can’t finish the vaccination series before departure.

The infection is endemic in the southern plains bordering India (Terai Districts). Cases have also been reported from the highlands, including the Kathmandu valley. Transmission occurs from June to October.

Rabies is a viral infection caused by viruses belonging to the Lyssavirus genus. It is a zoonosis (an animal disease that can spread to humans) transmitted through the saliva of infected mammals bites. The infection primarily circulates among domestic and wild animals such as dogs, cats, monkeys, foxes, bats, raccoons, and skunks, although all mammals are at risk. The virus attacks the Central Nervous System targeting the brain and the spinal cord, and if untreated is fatal.

Risk: Rabies is present on all continents except Antarctica. The majority of human infections occur in Asia and Africa. Travellers coming into close contact with domestic animals or wildlife on ecotourism trips, or those undertaking outdoor activities like cave exploring, camping, trekking, and visiting farms or rural areas are at higher risk. Rabies is also an occupational hazard for veterinarians and wildlife researchers. Children are especially vulnerable since they may not report scratches or bites. They should be cautioned not to pet dogs, cats, monkeys, or other mammals. Any animal bite or scratch must be washed repeatedly with copious amounts of soap and water. Seek medical attention immediately.

Symptoms: Usually appear 1 to 3 months or later, although they can appear as early as a few days after being infected. The illness is characterized by fever and pain or a tingling sensation at the wound site. As a result of inflammation to the brain and spinal cord, some patients present with anxiety, hyperactivity, convulsions, delirium, and have a fear of swallowing or drinking liquids, as well as a fear of moving air or drafts. In other patients, muscles become paralysed followed by a coma. Once symptoms are present, most patients die within 1 or 2 weeks.

Prevention: Avoid contact with feral animals or wildlife. Try to anticipate an animal’s actions and always be careful not to make sudden moves or surprise them. If you’ve been bitten by a mammal, wash the wound repeatedly and thoroughly with soap and water. Seek medical attention immediately.

Vaccination: A series of 3 pre-exposure rabies vaccination shots is advised for persons planning an extended stay or on working assignments in remote and rural areas, particularly in Africa, Asia, Central and South America. The pre-exposure series simplifies medical care if you have been bitten by a rabid animal and gives you enough time to travel back from a remote area to seek medical attention. Although this provides adequate initial protection, you will require 2 additional post-exposure doses if you are exposed to rabies. The preferred vaccines for rabies pre-exposure vaccination and post-exposure therapy are HDCV (Human Diploid Cell Rabies vaccine) and PCEC (Purified Chick Embryo Cell vaccine). These two vaccines are interchangeable.

Travellers who have not received the pre-exposure shots need 4 injections (those with compromised immune systems need 5 injections) and the Human Rabies Immune Globulin (HRIG) which is calculated as 20 IU (International Units) per kilo of body weight. HRIG must be injected around the bite site and intramuscularly. In some countries purified Equine Rabies Immune Globulin (ERIG) is used for post-exposure therapy when HRIG is not available. HRIG is in short supply worldwide and is often not available in rural and remote areas.

Note: If you are in a remote area and offered daily rabies injections lasting 14 to 21 days, it may be one of the older animal brain-derived vaccines. We recommend that you do not take them due to serious side effects.