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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 acute mountain sickness (AMS) and periodic breathing (PB) are common upon reaching altitudes of 8,000 feet or more.  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 may be relieved by physical activity, only to return again upon relaxing or resting.  Acetazolamide (Diamox®) readily relieves the symptom of periodic breathing both during the daytime and nighttime.

AMS, commonly referred to as high altitude sickness, is a concern for travelers to mountainous regions.  It is likely to occur in "flatlanders" who fly into airports located at high elevation, such as La Paz, Bolivia which has the highest paved airport in the world, at 13,313 ft. (4063 m).  Even experienced climbers making rapid ascents in climbing expeditions may be troubled by AMS.  Susceptible persons may experience AMS when driving from their low altitude residence to moderately high elevations for vacation.

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

Travelers flying into any high altitude location like La Paz, Bolivia and Cuzco, Peru are at a disadvantage because they do not have time to acclimate like slow moving climbing expeditions.  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 may 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 in the Andes call AMS "soroche" and recommend a tea made from the leaves of the coca plant.  Coca leaves have a rich history in the Andes and the tea is offered at all hotels.  Also, it is prized by the locals for aiding digestion, used as part of religious ceremonies and appears to have a mild stimulant effect.

Soroche pills (also known as Sorojchi High Altitude pills) are sold in drugstores possibly more for commercial reasons than medical effect.  The Sorojchi brand medication has a highly visible advertisement campaign, with posters in the front of pharmacies, showing 4 trekkers smiling and the 5th vomiting, presumably because he didn't take Sorojchi pills. 

Mountain climbers may experience AMS in spite of resting at camps for acclimatization.  Climbers on Mount Kilimanjaro 19,330 ft, (5892 m) have a high rate of AMS because it does not require a high degree of technical skill to climb, thus, the summit may be reached without long rest periods for acclimatization.  For this reason, some experts recommend that all climbers on Mount Kilimanjaro use acetazolamide (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®) has a long history of use in the treatment of the common eye disease, glaucoma.  It has also been shown to be 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 small dose is usually effective and results in minimal side effects.  The most commonly reported side effects are the sensation of mild tingling of the finger tips and the causing of carbonated beverages to taste strangely flat. 

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

Treatment of AMS after the unset of symptoms may require acetazolamide 250 mg twice a day.  Higher dosages can cause lightheadedness and an uncomfortable pins and needle tingling around the mouth, fingers tips and toes.  Analgesics, such as acetaminophen, ibuprofen, or aspirin are helpful for headache.  Keeping properly hydrated is important. 

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

Acetazolamide is a very mild diuretic and 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.  It is not recommended in those with kidney failure.

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

Dexamethasone (Decadron®) is a potent steroid that can be used for AMS.  The dose is 4 mg every six hours.  It is usually used to treat AMS symptoms or the more serious conditions of high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE).  It can be used to prevent AMS symptoms when acetazolamide (Diamox®) is not tolerated.   Short term use is considered safe, but this medicine can cause significant blood sugar elevation in diabetics.

Ondansetron (Zofran®) though not a new drug, has recently been promoted in the field of AMS.  It does not prevent AMS like acetazolamide, but is particularly useful for treating the nausea and vomiting that may accompany AMS.  This drug is well tolerated and avoids the drowsiness and extra-pyramidal (neurologic) side effects that may occur with other anti-emetics (anti-nausea drugs). 

Climbing expeditions higher than routine tourist destinations should carry dexamethasone (Decadron®) 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 should be treated with immediate descent, oxygen and diuretics.

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

Questionable treatments for AMS:

  • Salmeterol (Advair®) comes as a dry powder to inhale by mouth using a specially designed inhaler for 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. 

  • Captopril (Capoten®) is being offered to tourist for treatment of AMS.  Both nifedipine and captopril are potent drugs for lowering blood pressure and may cause fainting.  Neither drug has studies that show them effective in AMS nor should they be relied upon. 

  • Ginkgo biloba

  • Tibetan ginseng also known as Hong Jin Tian, or the "red view of heaven" is a tea made from rhodiola, a common plant in cold mountainous regions. 

  • Sorojchi High Altitude pills are a combination of acetylsalicylic acid, salophen and caffeine.  Basically this would be similar to aspirin with caffeine.

  • Mate de Coca known as Infusion de Coca is a tea made from coca leaves and at best is a mild stimulant.  It is illegal to bring coca leaves into the US.  Use of coca leaves may result in a positive urine drug screen for cocaine. 

  • Coramina glucosa is called the Peruvian favorite for AMS.
     

Research studies showing effectiveness of the above mentioned herbs and medications is lacking at this time.

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 analgesics, such as acetaminophen, ibuprofen or aspirin for headache.

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

  7. Use acetazolamide (Diamox®) until acclimatized.

Bedbugs
Bedbug bites are not a disease but are the result of an infestation of sleeping quarters and beds.  A resurgence of bedbugs has been reported in North America, Europe and Australia possibly related to the dramatic increase in traveling world wide.  Bedbugs may be found in a wide variety of locations in the urban environment, including single-family dwellings, apartments, hospitals, rooming houses and shelters.  These creatures have various names (and spellings) 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. 

There is little data to support bed bugs as vectors for transmission of human disease agents. After feeding on an infectious blood meal, bed bugs excrete hepatitis B surface antigen in their feces and could be a possible source of HBV infection by contamination of skin lesions or mucosal surfaces, or by inhalation of dust. However, their transmission of a human disease is yet to be firmly established. 
From "Bed Bugs (Cimex lectularius) and Clinical Consequences of Their Bites" by Goddard J, deShazo, RD. JAMA, April 1, 2009 - Vol 301, No. 13, pg. 1365.

These wingless creatures are 5-7 mm (1/4 inch) long, reddish brown, blood sucking, true bugs that pierce the skin of sleeping victims to feed.  They may resemble an unfed tick or a small cockroach to the untrained eye.  Bedbug infestation can be determined by looking for specks of brown or black fecal smears under mattress covers and along seams, along the bed frame and along box springs seams. 

Sometime after feeding on their victims, small raised inflamed bite sites appear that itch intensely.  These are usually treated with topical steroid creams and antihistamines.  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.  Once established, bedbugs may be difficult to eradicate.  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 the inside of luggage with an appropriate aerosol insecticide.  For a good review of the subject with photos see:
http://lancaster.unl.edu/pest/Resources/BedBug263.shtml

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.  Avoid 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 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, though they are infectious to anyone in intimate contact and may contaminated the food and water of others. 

Older children, adolescence and adults have a significant and prolonged illness of 3-4 weeks with fever, jaundice (yellow skin and eyes), right upper abdominal pain, nausea and vomiting, fatigue, and dark or tea colored urine. Symptoms do not appear until 4-6 weeks after exposure.  A person becomes infectious to others several weeks before symptoms appear.  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 in those with chronic liver disease.

Hepatitis A is usually contracted by ingestion of contaminated food and water in restaurants.  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 may occur during standard vacation itineraries, and at "five star hotels" in developing countries.  Hepatitis A is virtually 100% preventable by vaccination or by an 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.

On February 25, 2009, the Advisory Committee on Immunizations Practice (ACIP) recommended routine hepatitis A vaccination for all household members and other close personal contacts (e.g., regular baby-sitters) of adopted children newly arriving from countries with high or intermediate hepatitis A infection rates.  This is based on numerous episodes of hepatitis A infections occurring in family members and close contacts of adopted children brought to the US.
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5836a4.htm

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 for both pediatric and adult patients after 6 to 12 months.  The frequency of or need for further boosters has not been determined.  Experts believe there is life time protection after a single booster.

In regard to immunocompromised persons from cancer, immune disorders, or immunosuppressive therapy no special precautions are needed. However, the response to vaccination may be less than desired, in which case, immune globulin (IG) may be considered.

The safety of hepatitis A vaccine during pregnancy has not been determined.  Because hepatitis A vaccine is produced from inactivated hepatitis A virus, the theoretical risk to the developing fetus is expected to be low.  As an alternative, immune globulin (IG) is a safe and effective means of preventing hepatitis A.  Travel & Routine Immunizations 2009-2010, 18th ed, pg 68, Shoreland, Inc. 

Hepatitis A vaccine may be given to anyone wanting travel protection in any country.  The following countries are very low risk and vaccination is not generally recommended:

  • USA

  • Western Europe

  • New Zealand

  • Australia

  • Canada

  • Japan

A combination vaccine containing both hepatitis A and B vaccines is very effective and convenient when both hepatitis A and B vaccination is desirable.  See Twinrix® below.

Hepatitis B
Hepatitis B was called "serum hepatitis" because it was associated with blood transfusions.  It is now known that this virus has been transmitted in many different types of 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 of exposure 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 develop cancer of the liver. 

Hepatitis B infection is vaccine preventable.  Any person who performs tasks involving contact with blood, blood-contaminated body fluids, needles or other 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.

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