>

Travel Diseases & Vaccines
Page One

Page 1
Acute Mountain Sickness & Periodic Breathing
Bedbugs
Dengue Fever
Hepatitis A & B
Page 2
Japanese Encephalitis
Malaria
Meningococcal Meningitis
Polio
Rabies
Page 3
Tick-Borne Encephalitis
Travelers' Diarrhea
Typhoid Fever
Whooping Cough (Pertussis)
Yellow Fever

Acute Mountain Sickness (AMS) & Periodic Breathing (PB)
Both AMS and PB are common illnesses upon reaching altitudes of 8,000 feet or more. 

The symptoms of AMS are mild to severe headache, lethargy, nausea, restlessness at night with difficulty sleeping.  About 20% to 40% of travelers experience AMS to some degree.

AMS, sometimes called high altitude sickness, occurs by flying into airports located at very high elevation, making rapid ascents in climbing expeditions and sometimes by simply driving to moderate elevations. Travelers flying into La Paz, Bolivia which has the highest paved airport in the world, (13313 ft, 4063 m) often suffer from AMS. 

Travelers flying into La Paz, Bolivia and Cuzco, Peru are at a disadvantage because they do not have time to acclimate nor can they easily go back down to a lower altitude for relief of symptoms.  Administering oxygen or descending 1000 feet can bring significant and rapid improvement in symptoms.   Consequently, some hotels in the Andes or other high altitude tourist locations have oxygen bottles for patrons to use.

Ravenhill first described AMS in 1913 in Chile, calling it "puna."

It is a curious fact that the symptoms of puna do not usually evince themselves at once.  The majority of newcomers have expressed themselves as being quite well on first arrival.  As a rule, towards the evening, the patient begins to feel rather slack and disinclined for exertion.  He goes to bed but has a restless and troubled night and wakes up next morning with a severe frontal headache.  (Ravenhill TH.  Some experiences of mountain sickness in the Andes.  Journal of Tropical Medicine & Hygiene 1913;20:313-22)

The locals call AMS "soroche" and highly recommend a tea made from the leaves of the coca plant.  This tea is offered at all hotels and is particularly prized by the locals for aiding digestion. Coca leaves have a rich history in the Andes and are also used as part of religious ceremonies.  It appears to be a rather mild stimulant.

Soroche pills are sold in drugstores possibly more for commercial reasons than medical effect.  The soroche brand medication has a highly visibility advertisement campaign with posters in the front of pharmacies showing 4 trekkers smiling and the 5th throwing up.  Soroche pills contain caffeine among other ingredients.

There are no studies on the use of coca leaves, coca tea or soroche pills for prevention or treatment of AMS.  It is illegal to bring coca leaves into the US and use of them may result in a positive urine drug screen for cocaine. 

Mountain climbers may experience AMS in spite of resting at camps for acclimatization.  Climbers on Mount Kilimanjaro (19,330 ft, 5892 m) have a very high rate of AMS.  Kilimanjaro does not require a high degree of technical skill to climb, thus, the summit can be reached without long rest periods and acclimatization.  For this reason, some experts recommend that all climbers on Mount Kilimanjaro use Diamox to prevent AMS. 

In three different studies, children were noted to experience AMS at the same rate as adults. 

Under 3 years of age, travel to any new environment may result in alterations of sleep, appetite, activity, and mood. Differentiating behavioral changes caused by travel alone from changes caused by altitude illness can be difficult.  Because of variability in the developmental level of perception and expression in young children, they are not reliable reporters of symptoms of altitude illness even when they can talk.

Symptoms may appear as nonspecific behavioral changes, rather than specific complaints of headache or nausea. The typical symptoms of acute mountain sickness in very young children include increased fussiness, decreased appetite and possibly vomiting, decreased playfulness, and difficulty sleeping. These symptoms usually begin 4 to 12 hours after ascent to altitude. 
www.ismmed.org/ISMM_Children_at_Altitude.htm

Acetazolamide (Diamox®) is very effective in preventing or lessening symptoms of AMS.  The newer dosing recommendation is 3-5 mg/kg/day in two divided doses, about 125 mg twice a day for adults.  Start the night before reaching altitude.  This smaller dose is usually effective and results in less side effects.  A mild numb feeling of the finger tips is not usual and carbonated beverages will taste strangely flat. 

This dosage may be less than enough for larger patients and a third dose can be taken mid day or during the night if headache or other symptoms appear.  Most people acclimate within three to four days, though symptoms may reappear on the next trip to that altitude. 

Treatment of AMS after the unset of symptoms may require 250 mg twice a day.  Anti-inflammatory drugs are also helpful. Keeping properly hydrated is important.  Higher dosages can cause lightheadedness and an uncomfortable pins and needle tingling around the mouth, fingers tips and toes.

Acetazolamide appears to be safe in children of all ages at 3 mg/kg/day in two divided doses.

Acetazolamide increases urine output.  If you are on a diuretic, such as, furosemide (Lasix®) or HCTZ (hydrochlorothiazide) do not decrease or stop them, as the diuretic effect of acetazolamide is small.

Traditionally, the use of acetazolamide has been discouraged in people with known allergy to sulfa antibiotics.  Recent literature indicates that there may be no increased allergic risk with non-antibiotic sulfa drugs, such as acetazolamide.  ("Absence of Cross-reactivity Between Sulfonamide Antibiotics and Sulfonamide Nonantibiotics." NEJM 2003; 349(17):1628-1635.)  It is a category C drug and not recommended in pregnancy or breast feeding due to lack of safety studies.

Periodic breathing (PB) is considered to be a normal phenomena at high altitude.  This is a cyclic pattern of increasingly rapid breathing, followed by a slowing of the cycle to near stopping.  The cycles continue  repeatedly.  PB can disrupt sleep at night and be annoying during the day.  Daytime symptoms are relieved by any physical activity, only to return again upon relaxing or resting.  Acetazolamide readily relieves the symptom of periodic breathing both during the daytime and nighttime.

Local guides and pharmacies often encourage only coca leaves and soroche pills.  You may have difficulty finding acetazolamide in Cuzco or other cities of the Andes. 

Steroids have been shown to be very effective in prevention and treatment of AMS. Adults are usually given dexamethasone 4 mg (Decadron®) every six hours.  Children will respond to lower doses.  Short term use is considered safe, but this medicine can cause significant blood sugar elevation in diabetics.  As a preventative, this medication is prescribed for those that can not take acetazolamide.

Climbing expeditions higher than routine tourist destinations should carry dexamethasone to treat severe AMS, high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE).

AMS is not the same as high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE).  These are two serious and life threatening conditions that require urgent medical attention.

HAPE is fluid build up in the lungs marked by increasing shortness of breath and associated with persistent cough, severe headache, confusion and finally collapse.  It is treated with immediate descent, oxygen and diuretics.

HACE is swelling of the brain whose hallmark is difficulty thinking, causing disorientation, confusion and collapse.  It is treated with immediate descent, oxygen, diuretics and steroids.

Salmeterol in an inhaled bronchodilator that is used in the treatment of asthma and COPD.  It has shown some effect in HAPE in only one study.  It has not been studied in AMS and should not be relied upon. 

Nifedipine (Procardia®) is used chiefly for treatment of angina and hypertension but has shown slight effect in HAPE, as have Cialis® and Viagra® which are used to treat erectile dysfunction.  There are no studies that show these drugs effective in AMS nor should they be relied upon.

Ginkgo biloba extract has never been studied in AMS and should not be relied upon.

Summary tips for moderate high altitude trips, such as, Cuzco:

  1. Don't drink alcohol for 1 to 2 days.

  2. Refrain from or minimize smoking.

  3. Don't over exert yourself.

  4. Plan on relaxing in Cuzco several days before excursions.

  5. Use an anti-inflammatory, such as, ibuprofen for headache.

  6. Ask your hotel manager for oxygen if needed.  (NEVER smoke around oxygen)

  7. Use acetazolamide (Diamox®) until acclimatized.

Bedbugs
Bedbugs are not a disease but an infestation  A resurgence of bedbugs has been reported in North America and Europe possibly related to the dramatic increase in traveling world wide. Bedbugs are found in a wide variety of locations in the urban environment, including single-family dwellings, apartments, rooming houses and shelters.  These creatures have various names including:  bed bugs, bedbugs, wall-lice, redcoats, mahogany flats, chinches and the chinch bug. Cimex lectularius is the common bedbug and Cimex hemipterus is the tropical bedbug.

Bedbugs are usually not found on their victims except when feeding at night.  They hide in crevices of bedding, mattresses, beds, flooring and furniture or behind peeling paint and wall paper.  Some experts believe that Chagas disease and hepatitis B may be transmitted by bedbugs.

These creatures are 5-7 mm long, reddish brown, blood sucking, true bugs that pierce the skin of sleeping victims to feed.  Small raised inflamed bite sites appear that itch intensely.  If no victims are available, they may live for up to one year without feeding.

Bedbugs may be imported home with you in luggage, clothes or any purchased items.  On returning home, launder all clothes or dry clean.  Check luggage or other items for these creatures hiding in crevices.  Vacuum out and lightly fog inside of luggage with house & garden insecticide and then close up.

Dengue Fever (DF)
DF is the most common arboviral disease (mosquito transmitted viral disease) in the world. It is caused by a virus similar to the West Nile Virus (WNV).  DF is only transmitted by the Aedes aegpyti mosquito and it's close relative the Aedes albopictus known also as the Asian tiger mosquito because of it's aggressive biting habits. 

These mosquitoes are found along the southern USA, down through Mexico, Central America, South America, the Caribbean and Pacific, Asia, India, Torres Strait of Australia and parts of Africa.  DF is only occasionally reported in the USA in Texas, and last reported in Maui, Hawaii in 2002.

The Aedes aegpyti mosquito is a day time bitter and highly domesticated.  It prefers residential areas.  Breeding occurs around homes where it lays eggs in any standing water, such as, in flower pots on outside porches, water buckets, discarded tin cans and tires, and roof gutters.  Biting may occur in any residential,  rural or urban area.

In the tropics, cases of DF have been rising steadily for years.  Epidemics of thousands can occur in certain areas, depending on rainfall and other factors.  DF is usually an adult disease whereas, Dengue Hemorrhagic Fever (DHF) is more common in children and can be fatal.  In many areas of the tropics, the risk of contracting DF is much higher than malaria.   Dengue fever maps.

DF has the common name of "break-bone fever" causing severe headache, pain behind the eyes, muscle and joint pain and fever.  A faint rash is often present in DF.  Symptoms last 7 to 10 days.  For mild cases, treatment is symptomatic with Tylenol or other pain relieving agents, fluids and rest.  Avoiding aspirin or aspirin like products such as ibuprofen (Advil) and naproxen (Aleve).  Symptoms can easily be confused with malaria.  Protect yourself with DEET or picaridin mosquito repellants.  There is no licensed vaccine.

Hepatitis A & B
Hepatitis A and hepatitis B infections (and influenza) are the most common vaccine preventable diseases in the world. 

Hepatitis A
Hepatitis A was commonly called “infectious hepatitis,” a word coined in 1912 to describe the epidemic form of the disease.  This is an infection of the liver that is usually very mild in young children and may go unnoticed.  Symptoms do not appear until 4-6 weeks after exposure.  A person becomes infectious several weeks before symptoms appear. 

Older children, adolescence and adults have a more significant and prolonged illness (3-4 weeks) with fever, jaundice (yellow skin and eyes), abdominal pain under the ribs on the right side, nausea and vomiting, fatigue, dark or tea colored urine.  Complete recovery may take one month or more.  Full recovery is usually the case.  There is a fatality rate of 1 to 2 percent in persons over the age of 60 years, in those immunocompromised by other illnesses or those with chronic liver disease.

Hepatitis A is contracted by ingestion of fecally contaminated food and water.  However, it can be acquired by close contact with infected persons in day care centers, schools, and homes.  Large outbreaks occasionally occur in the US from contaminated produce, as in March 1997, when a total of 153 cases of hepatitis A were reported in Calhoun County, Michigan.  

Travelers may contract hepatitis A when infected food handlers contaminate food, water and ice through poor hand washing and hygiene.  Infections can occur during standard vacation itineraries in developing countries.  Hepatitis A is preventable by vaccination or by immunoglobulin (IG) injection prior to travel.

On October 19, 2007 the CDC updated the ACIP recommendations regarding the use of hepatitis A vaccine and IG for prevention of hepatitis A, after exposure to hepatitis A virus and in international travelers.

Hepatitis A Vaccine
This highly effective vaccine was licensed in the US in 1995.  A single dose given even after exposure is protective in most cases, so that vaccination of a traveler the day of departure should be done if necessary.  The Canadian National Advisory Committee on Immunization states that a single dose of hepatitis A vaccine may provide protection for travelers who are immunized shortly before departure.

In 2006, the minimum recommended age for vaccination was lowered from age 2 years to age 1 year old.  Adult doses are given from age 19 years on.  A booster is given after 6 to 12 months for long term protection.  The frequency of or need for further boosters has not been determined.  Experts believe there is life time protection after a single booster.

Hepatitis A vaccine may be given to anyone wanting protection, though the following countries are low risk:

  • USA

  • Western Europe

  • New Zealand

  • Australia

  • Canada

  • Japan

A combination vaccine containing both hepatitis A and B vaccines is very useful and convenient.  See Twinrix® below.

Hepatitis B
Hepatitis B was called "serum hepatitis" because it was sometimes associated with blood transfusions.  It is now known that this virus is transmitted in blood products and in body fluids or by items contaminated with them.  Thus, hepatitis B can be transmitted through sharing contaminated needles, pierced earrings, shaving razors, and toothbrushes, tattoos, needle sticks, acupuncture,  body piercing, dental work,  and sexual intercourse.  In up to 40% of  cases, the exact source may be unknown.

Hepatitis B virus is not transmitted casually and cannot be spread through sneezing, coughing, hugging or by food or water.  It is 50-100 times more infectious than the AIDS virus.

Symptoms of infection are the same as with hepatitis A but often less dramatic.  Infection may not become apparent until two months after exposure due a prolonged incubation time.  Unlike hepatitis A, hepatitis B can result in a chronic carrier state in which one remains infectious for life. Also, unlike hepatitis A, 10% of hepatitis B chronic carriers will develop cirrhosis of the liver and 10% of those will develope cancer of the liver. 

Hepatitis B infection is vaccine preventable.  Any person who performs tasks involving contact with blood, blood-contaminated body fluids, or sharps should be vaccinated against hepatitis B.  All health care workers are routinely immunized in the US and other developed countries.

Travelers should be vaccination if they frequently travel to, or spend more than one month in, countries that have intermediate to high rates of hepatitis B infections.  These areas include Asia, India, Africa, the Middle East, Eastern Europe, the Pacific, South America and Alaska. 

When possible, adopting parents should learn the hepatitis B status of the child and vaccinate household contacts, as needed, prior to adoption.

International travelers to areas of intermediate or high rates of hepatitis B or engaging in any of the below activities should be vaccinated for hepatitis B:

  • Travelers engaging in tattooing, body piercing, and acupuncture.

  • Travelers engaging in sexual activity or daily physical contact with local populations, or who are likely to seek medical, dental, or other treatment from local facilities.

  • Travelers with direct exposure to blood in medical, dental, laboratory or blood transfusions where blood has not been tested. 

  • Travelers with exposure to needles that have not been properly sterilized or who are injecting drugs.

  • Travelers with direct exposure to body wounds, such as, adults and children with impetigo, scabies, scratched insect bites in less developed countries.

Vaccination should be considered for all young people regardless of travel plans, as a matter of good health maintenance.  In adults this vaccine is usually given as three doses over six months, but an hyper-accelerated schedule over 21 days with a final booster after 12 months can be used. 

Twinrix® is a well accepted combination vaccine for the prevention of hepatitis A and hepatitis B.  It  is normally given on the same schedule as hepatitis B.  In May of 2007, the US  approved the use of Twinrix® in an accelerated dosing schedule of days 0, 7, and 21 with a final booster in one year.  This schedule is very useful for travelers leaving in less than a month because they complete the series in 21 days instead of six months.  To ensure lifelong protection a booster at 1 year is recommended.

Page 1
Acute Mountain Sickness
Bedbugs
Dengue Fever
Hepatitis A & B
Page 2
Japanese Encephalitis
Malaria
Meningococcal Meningitis
Polio
Rabies
Page 3
Tick-Borne Encephalitis
Travelers' Diarrhea
Typhoid Fever
Whooping Cough (Pertussis)
Yellow Fever

Back to top