The Student Health Center provides comprehensive travel health services to those students traveling abroad, whether you are going for a short trip for a class, a full semester or as an individual traveler.
Malaria is a serious and sometimes fatal disease caused by a parasite that can infect a certain type of mosquito which feeds on humans. About 1,500 cases of malaria are diagnosed in the United States each year. Almost all are in travelers and immigrants returning from parts of the world where malaria transmission occurs, mainly sub-Saharan Africa and South Asia. All travelers who visit a country where malaria transmission occurs should take precautions against contracting malaria. First and second-generation immigrants are at very high risk of malaria infection because they may not realize that they have lost any partial protection that they had against malaria.
Malaria transmission occurs in many tropical and subtropical countries (see map). View the CDC's list of all the places in the world where malaria transmission occurs and the malaria drugs that are recommended for use in each place. If you are traveling to parts of the world where malaria transmission occurs, you could be at risk for malaria.
The cornerstone of malaria prevention is to avoid mosquito bites. Mosquitoes that transmit malaria, bite between dusk and dawn. Other measures to prevent mosquito bites include:
- Stay indoors between dusk and dawn.
- If outdoors, wear a long-sleeved shirt, long pants, and a hat.
- Apply insect repellent to exposed skin.
More Information on Insect Repellents
DEET (concentration of 20% or more) is the only insect repellent shown to be effective against ticks. Concentrations <10% active ingredient may offer only limited protection (1-2 hours). Concentrations above 50% show no additional protective benefit. Use repellents and reapply only as instructed. If sunscreen is also needed, apply sunscreen first and repellent second.
If you will not be staying in well-screened or air-conditioned rooms, take additional precautions, such as sleeping under an insecticide-treated bed net (mosquito netting). Bed nets sprayed with the insecticide permethrin are most effective. In the United States, you can buy permethrin as a spray or liquid to treat clothes and bed nets and you can also purchase bed nets that have already been treated with permethrin.
Visit the Student Health center 6-8 weeks before your trip for a travel evaluation if you are going to a developing country, particularly to Africa, South America, Central America or Asia. A prescription for an antimalarial drug based on your travel itinerary and medical history may be recommended. Antimalarial drugs are available in the United States by prescription only.
Some antimalarial drugs can be started the day before travel and so last-minute travelers can still benefit from a visit to the student health center or their health-care provider before traveling. Fill your prescription before you travel rather than at your destination because buying medications in a foreign country can be risky. The medication may be contaminated or counterfeit and therefore will not protect you from malaria.
All medicines may have some side effects. Minor side effects such as nausea, occasional vomiting, or diarrhea usually do not require stopping the antimalarial drug. If you have side effects that are too uncomfortable, see a health-care provider; other antimalarial drugs are available.
Travelers’ diarrhea (TD) is the most common travel-related illness experienced in people traveling abroad. Following simple recommendations such as “boil it, cook it, peel, it, or forget it,” may help reduce the incidence of (TD) but studies have found that people who follow these measures may still become ill. Poor hygiene practice in local restaurants is likely the largest contributor to the risk of TD.
(TD) is an illness that can result from a variety of intestinal pathogens. Bacterial pathogens are the predominant risk, thought to account for 80-90 percent of (TD). Intestinal viruses have been isolated in studies of (TD), but they usually account for only 5-8 percent of illnesses. Protozoal pathogens are slower to cause symptoms and are thought to account for approximately 10 percent of diagnoses in longer-term travelers.
The most important risk factor for contracting (TD) is the travel destination. There are regional differences in both the risk for and cause of diarrhea. The world is generally divided into 3 grades of risk: low, intermediate, and high.
- Low-risk countries include the United States, Canada, Australia, New Zealand, Japan, and countries in Northern and Western Europe.
- Intermediate-risk countries include those in Eastern Europe, South Africa, and some of the Caribbean islands.
- High-risk areas countries include those in most of Asia, the Middle East, Africa, Mexico, and Central/South America.
Bacterial diarrhea presents with the sudden onset of symptoms that can range from mild cramps and loose stools to severe abdominal pain, fever, vomiting, and bloody diarrhea. Viral caused diarrhea presents in a similar fashion to diarrheal illnesses caused by bacterial pathogens. Protozoal diarrhea, often has a more gradual onset, 1-2 weeks, with milder symptoms, usually 2-5 loose stools per day.
Untreated bacterial diarrhea usually lasts 3-5 days while untreated viral diarrhea lasts 2-3 days. Protozoal diarrhea can persist for weeks to months without treatment.
To avoid illness, travelers should select food with care. Raw or undercooked meat, fish, and shellfish can carry various intestinal pathogens. Particularly in areas where hygiene and sanitation are inadequate, travelers should avoid salads, uncooked vegetables, unpasteurized fruit juices, and unpasteurized milk and milk products, such as cheese and yogurt. Eat only food that is fully cooked and served hot and fruit that has been washed in clean water and then peeled by the traveler. Raw fruits that are eaten unpeeled (such as strawberries) or cut should be avoided, and fruits that are eaten peeled (such as bananas) should be peeled by the person who eats them. Always refrigerate perishable cooked food within 2 hours (1 hour at temperatures >90 F. Cooked food that has been stored should be thoroughly reheated before serving. These recommendations also apply to eggs, which should be thoroughly cooked, whether they are served alone or used in sauces. Food and beverages obtained from street vendors have been associated with an increased risk of illness.
Travelers should wash their hands with soap and water before eating and after using the bathroom If soap and water are not available, use an alcohol-based hand sanitizer (with >60% alcohol).
In many parts of the world, tap water contains disease-causing contaminants, including viruses, bacteria, and parasites. As a result, tap water in some places may be unsafe for drinking, preparing food and beverages, making ice, cooking, and brushing teeth.
Avoid drinking tap water unless there is reasonable certainty it is not contaminated. Some people choose to disinfect or filter their water when traveling to destinations where safe tap water may not be available. Water contaminated with fuels or toxic chemicals, however, will not be made safe by boiling or disinfection; travelers should use a different source of water if they suspect this type of contamination.
In areas where tap water may be contaminated, commercially bottled water from an unopened, factory-sealed container or water that has been adequately disinfected should be used for brushing teeth and other oral hygiene.
Beverages made with boiled water and served steaming hot (such as tea and coffee) are generally safe to drink. When served in unopened, factory-sealed cans or bottles, carbonated beverages, commercially prepared fruit drinks, water, alcoholic beverages, and pasteurized drinks generally can be considered safe. Because water on the outside of cans and bottles may be contaminated, they should be wiped clean and dried before opening or drinking directly from the container.
Beverages that may not be safe for consumption include fountain drinks, fruit drinks made with tap water, iced tea, and iced coffee. Because ice may be made from contaminated water, travelers in areas with unsafe tap water should request that beverages be served without ice.
The primary medication used for prevention of (TD) is bismuth subsalicylate (BSS), which is the active ingredient in Pepto-Bismol. Studies from Mexico have shown this agent (taken daily as either 2 oz of liquid or 2 chewable tablets 4 times per day) reduces the incidence of (TD) by approximately 50%. BSS commonly causes blackening of the tongue and stool and may cause nausea, constipation, and rarely ringing in the ears. BSS should be avoided by travelers with aspirin allergy, renal insufficiency, and gout and by those taking blood thinners, probenecid, or methotrexate. Studies have not established the safety of BSS use for periods >3 weeks.
Since bacterial causes of (TD) far outnumber other microbial causes, antibiotics are often used in the treatment for (TD). Travelers to low and intermediate risk countries should bring along an antibiotic, prescribed by a provider, to be started promptly if significant diarrhea occurs. Significant diarrhea is defined as three or more loose stools in an 8-hour period or five or more loose stools in a 24-hour period, especially if associated with nausea, vomiting, cramps, fever or blood in the stool. Seek medical attention if diarrhea is severe or bloody, or if fever occurs with shaking chills, or if abdominal pain becomes marked, or if diarrhea persists for more than 72 hours. Though effective for treating (TD), antibiotics are not recommended as a preventive measure.
* Most cases of travelers' diarrhea are mild and do not require either antibiotics or antidiarrheal drugs. Adequate fluid intake is essential.
Antimotility agents provide symptomatic relief in (TD). An agent such as loperamide can reduce the frequency of loose stools while awaiting the effects of antibiotics. The safety of loperamide, when used along with an antibiotic, has been well established. although antimotility agents such as Loperamide are not recommended for people experiencing bloody diarrhea or those who have diarrhea and fever.
Oral Rehydration Therapy
Fluids and electrolytes are depleted with TD, and replenishment is important. Replacement of fluid helps the traveler feel better more quickly. Travelers should remember to use only beverages that are sealed, treated with chlorine, boiled, or are otherwise known to be purified. For severe fluid loss, replacement is best accomplished with oral rehydration solution (ORS), prepared from packaged oral rehydration salts, such as those provided by the World Health Organization, which are widely available at stores and pharmacies in most developing countries. ORS is prepared by adding 1 packet to the indicated volume of boiled or treated water. In mild cases of (TD), rehydration can be maintained with any palatable liquid (including sports drinks), although overly sweet drinks, such as soda, can make diarrhea worse if consumed in large volumes.
Inadequate time to acclimate may lead to Acute Mountain Sickness (AMS) in any traveler ascending to 8,000 ft (2,500 meters) or higher. Susceptibility and resistance to altitude illness are genetic traits, and no simple screening tests are available to predict who will experience the symptoms. The risk is not affected by training or physical fitness. How a traveler has responded to high altitudes in the past is the most reliable guide for predicting symptoms of Acute Mountain Sickness in future trips. The risk is largely influenced by the rate of ascent and exertion and can be categorized by low, moderate and high risk. See full table 2-07 at the CDC website.
- People with no prior history of altitude illness and ascending to <9,000 ft (2,750 meters).
- People taking >2 days to arrive at 8,000-9,000 ft (2,500-3000 meters), with subsequent increases in sleeping elevation <1,600 ft (500 m) per day, and an extra day for acclimatization every 3,200 ft (1,000 meters).
- People with prior history of AMS and ascending to 8,000-9,000 ft (2,500-2,750 meters) in 1 day.
- No history of AMS and ascending to >9,000 ft (2,750 m) in 1 day.
- All people ascending >1,600 ft (500 meters) per day (increase in sleeping elevation) at altitudes above 9,000 ft (2,750 meters), but with an extra day for acclimatization every 3,200 ft (1,000 m).
- History of Acute Mountain Sickness and ascending to >9,000 ft (2,750 meters) in 1 day.
- All people with a prior history of high-altitude cerebral edema (HACE), and high-altitude pulmonary edema (HAPE).
- All people ascending to >11,400 ft (3,500 meters) in 1 day.
- All people ascending >1,600 ft (500 meters) per day (increase in sleeping elevation) above 9,000 ft (2,750 meters), without extra days for acclimatization.
- Very rapid ascents (such as <7-day ascents of Mount Kilimanjaro).
Symptoms of Acute Mountain Sickness
To have an idea of the extent of the problem, approximately 25% of all travelers sleeping above 8,000 ft (2,500 meters) in Colorado experience Acute Mountain Sickness. Symptoms are similar to those of an alcohol hangover. A headache is the primary symptom, sometimes accompanied by fatigue, loss of appetite, nausea, and occasionally vomiting. The onset of a headache is usually 2-12 hours after arrival at a higher altitude and often is experienced during or after the first night. Symptoms of Acute Mountain Sickness generally resolve with 24-72 hours of acclimatization.
Tips for acclimatization
- Ascend gradually, if possible. Try not to go directly from low altitude to >9,000 ft (2,750 meters) sleeping altitude in 1 day. Once at >9,000 ft (2,750 meters), move sleeping altitude no higher than 1,600 ft (500 meters) per day, and plan an extra day for acclimatization every 3,300 ft (1,000 meters).
- Discuss with your health care providers medication such as acetazolamide to speed acclimatization, if abrupt ascent is unavoidable.
- Avoid alcohol for the first 48 hours.
- Participate in only mild exercise for the first 48 hours.
- Having a high-altitude exposure at >9,000 ft (2,750 meters) for 2 nights or more, within 30 days before the trip, is useful.
* One severe and rare consequence of altitude illness is swelling of the brain (high-altitude cerebral edema (HACE). Symptoms include extreme fatigue, drowsiness, confusion, and loss of coordination. HACE is rare, but it can be fatal. If it develops, the person must immediately descend to a lower altitude.
Swelling of the lungs, (high-altitude pulmonary edema (HAPE) is also a rare consequence of acute mountain illness. Symptoms include being out of breath, weakness, and cough. A person with HAPE should also descend and may need oxygen.
All student information held at the Health and Wellness Center is strictly confidential, and will not be released without written or phone consent by the student. This includes inquiries from parents, private health care providers, professors, and other students. Students under 18 year of age must have parental permission to be seen and treated at the Health and Wellness Center, with the exception of emergency situations, emancipated minors, or reproductive health issues.