Travelers' diarrhea is the most common travel-related ailment. The cornerstone of prevention is food and water precautions, as outlined below. All travelers should bring along an antibiotic and an antidiarrheal drug to be started promptly if significant diarrhea occurs, 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. A quinolone antibiotic is usually prescribed: either ciprofloxacin (Cipro)(PDF) 500 mg twice daily or levofloxacin (Levaquin) (PDF) 500 mg once daily for a total of three days. Quinolones are generally well-tolerated, but occasionally cause sun sensitivity and should not be given to children, pregnant women, or anyone with a history of quinolone allergy. Alternative regimens include a three day course of rifaximin (Xifaxan) 200 mg three times daily or azithromycin (Zithromax) 500 mg once daily. Rifaximin should not be used by those with fever or bloody stools and is not approved for pregnant women or those under age 12. Azithromycin should be avoided in those allergic to erythromycin or related antibiotics. An antidiarrheal drug such as loperamide (Imodium) or diphenoxylate (Lomotil) should be taken as needed to slow the frequency of stools, but not enough to stop the bowel movements completely. Diphenoxylate (Lomotil) and loperamide (Imodium) should not be given to children under age two.

Most cases of travelers' diarrhea are mild and do not require either antibiotics or antidiarrheal drugs. Adequate fluid intake is essential.

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, medical attention should be sought.

Though effective, antibiotics are not recommended prophylactically (i.e. to prevent diarrhea before it occurs) because of the risk of adverse effects, though this approach may be warranted in special situations, such as immunocompromised travelers.

Malaria in Guyana: prophylaxis is recommended for all rural areas below 900 m (2953 ft). Risk is greatest in the northwest. Sporadic cases have also been reported from the coastal region. Either mefloquine (Lariam), atovaquone/proguanil (Malarone)(PDF), or doxycycline may be given. Mefloquine is taken once weekly in a dosage of 250 mg, starting one-to-two weeks before arrival and continuing through the trip and for four weeks after departure. Mefloquine may cause mild neuropsychiatric symptoms, including nausea, vomiting, dizziness, insomnia, and nightmares. Rarely, severe reactions occur, including depression, anxiety, psychosis, hallucinations, and seizures. Mefloquine should not be given to anyone with a history of seizures, psychiatric illness, cardiac conduction disorders, or allergy to quinine or quinidine. Those taking mefloquine (Lariam) should read the Lariam Medication Guide (PDF). Atovaquone/proguanil (Malarone) is a recently approved combination pill taken once daily with food starting two days before arrival and continuing through the trip and for seven days after departure. Side-effects, which are typically mild, may include abdominal pain, nausea, vomiting, headache, diarrhea, or dizziness. Serious adverse reactions are rare. Doxycycline is effective, but may cause an exaggerated sunburn reaction, which limits its usefulness in the tropics. Doxycycline has the advantage of also preventing leptospirosis (see "Recent outbreaks" below).

Long-term travelers who may not have access to medical care should bring along medications for emergency self-treatment should they develop symptoms suggestive of malaria, such as fever, chills, headaches, and muscle aches, and cannot obtain medical care within 24 hours. See malaria for details. Symptoms of malaria sometimes do not occur for months or even years after exposure.

Insect protection measures are essential.

The number of malaria cases has risen sharply in recent years due to increased gold mining and logging activities deep in the interior, in conjunction with underfinancing of malaria control programs over an extended period of time.

For further information about malaria in Guyana, go to the World Health Organization.

The following are the recommended vaccinations for Guyana.

Hepatitis A vaccine is recommended for all travelers over one year of age. It should be given at least two weeks (preferably four weeks or more) before departure. A booster should be given 6-12 months later to confer long-term immunity. Two vaccines are currently available in the United States: VAQTA (Merck and Co., Inc.) (PDF) and Havrix (GlaxoSmithKline) (PDF). Both are well-tolerated. Side-effects, which are generally mild, may include soreness at the injection site, headache, and malaise.

Older adults, immunocompromised persons, and those with chronic liver disease or other chronic medical conditions who have less than two weeks before departure should receive a single intramuscular dose of immune globulin (0.02 mL/kg) at a separate anatomic injection site in addition to the initial dose of vaccine. Travelers who are less than one year of age or allergic to a vaccine component should receive a single intramuscular dose of immune globulin (see hepatitis A for dosage) in the place of vaccine.

Typhoid vaccine is recommended for all travelers, with the exception of short-term visitors who restrict their meals to major restaurants and hotels, such as business travelers. It is generally given in an oral form (Vivotif Berna) consisting of four capsules taken on alternate days until completed. The capsules should be kept refrigerated and taken with cool liquid. Side-effects are uncommon and may include abdominal discomfort, nausea, rash or hives. The alternative is an injectable polysaccharide vaccine (Typhim Vi; Aventis Pasteur Inc.) (PDF), given as a single dose. Adverse reactions, which are uncommon, may include discomfort at the injection site, fever and headache. The oral vaccine is approved for travelers at least six years old, whereas the injectable vaccine is approved for those over age two. There are no data concerning the safety of typhoid vaccine during pregnancy. The injectable vaccine (Typhim Vi) is probably preferable to the oral vaccine in pregnant and immunocompromised travelers.

Yellow fever vaccine is recommended for all travelers greater than 9 months of age. The vaccine is required for travelers arriving from a yellow-fever-infected country in Africa or the Americas or from any of the following countries:

Africa: Angola, Benin, Burkina Faso, Burundi, Cameroon, Central African Republic, Chad, Congo, Cote d'Ivoire, Democratic Republic of the Congo, Gabon, The Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Liberia, Mali, Niger, Nigeria, Rwanda, Sao Tome and Principe, Senegal, Sierra Leone, Somalia, Tanzania (United Republic of), Togo, and Uganda.

Americas: Belize, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Guatemala, Honduras, Nicaragua, Panama, Peru, Suriname, and Venezuela.

Yellow fever vaccine (YF-VAX; Aventis Pasteur Inc.) (PDF) must be administered at an approved yellow fever vaccination center, which will give each vaccinee a fully validated International Certificate of Vaccination. The vaccine should not in general be given to anyone who is younger than nine months old, pregnant, immunocompromised, or allergic to eggs (since the vaccine is produced in chick embryos). Reactions to the vaccine, which are generally mild, include headaches, muscle aches, and low-grade fevers. Serious allergic reactions, such as hives or asthma, are rare and generally occur in those with a history of egg allergy.

Hepatitis B vaccine is recommended for travelers who will have intimate contact with local residents or potentially need blood transfusions or injections while abroad, especially if visiting for more than six months. It is also recommended for all health care personnel. Two vaccines are currently licensed in the United States: Recombivax HB (Merck and Co., Inc.) (PDF) and Engerix-B (GlaxoSmithKline) (PDF). A full series consists of three intramuscular doses given at 0, 1 and 6 months. Engerix-B is also approved for administration at 0, 1, 2, and 12 months, which may be appropriate for travelers departing in less than 6 months. Side-effects are generally mild and may include discomfort at the injection site and low-grade fever. Severe allergic reactions (anaphylaxis) occur rarely.

Rabies vaccine is recommended only for those at high risk for animal bites, such as veterinarians and animal handlers, and for long-term travelers who may have contact with animals and may not have access to medical care. In Guyana, bats are the leading source of infection. A complete preexposure series consists of three doses of vaccine injected into the deltoid muscle on days 0, 7, and 21 or 28. Side-effects may include pain at the injection site, headache, nausea, abdominal pain, muscle aches, dizziness, or allergic reactions.

Any animal bite or scratch should be thoroughly cleaned with large amounts of soap and water and local health authorities should be contacted immediately for possible post-exposure treatment, whether or not the person has been immunized against rabies.

Tetanus-diphtheria vaccine is recommended for all travelers who have not received a tetanus-diphtheria immunization within the last 10 years.

Measles-mumps-rubella vaccine: two doses are recommended (if not previously given) for all travelers born after 1956, unless blood tests show immunity. Many adults born after 1956 and before 1970 received only one vaccination against measles, mumps, and rubella as children and should be given a second dose before travel. MMR vaccine should not be given to pregnant or severely immunocompromised individuals.

Cholera vaccine is not recommended. Cholera is not being reported from Guyana at this time.

Polio vaccine is not recommended for any adult traveler who completed the recommended childhood immunizations. Polio has been eradicated from the Americas, except for a small outbreak of vaccine-related poliomyelitis in the Dominican Republic and Haiti in late 2000.

An outbreak of dengue fever, a flu-like illness sometimes complicated by hemorrhage or shock, was reported from Guyana in September 2008, causing approximately 300 cases. In May 2008, a small number of cases were reported from Lethem, near the border with Brazil, at the same time that Brazil was experiencing a major dengue outbreak. Dengue fever is transmitted by Aedes mosquitoes, which bite primarily in the daytime and favor densely populated areas, though they also inhabit rural environments. No vaccine is available at this time. The cornerstone of prevention is insect protection measures, described below.

An outbreak of leptospirosis was reported from Guyana in February 2005, following widespread flooding. Leptospirosis is transmitted to humans by exposure to water contaminated by the urine of infected animals. Outbreaks often occur at times of flooding, when sewage overflow may contaminate water sources. Initial symptoms may include fever, chills, headache, muscle aches, conjunctivitis (pink eye), photophobia (light sensitivity), and rash. Complications may include meningitis, kidney failure, liver failure, and bleeding into the lungs or gastrointestinal tract. Travelers can minimize their risk by avoiding exposure to bodies of fresh water that may be contaminated by animal urine. Those exposed to potentially contaminated water should take doxycycline 200 mg once weekly as prophylaxis. For further information, go to Health Canada and ProMED-mail.

Cutaneous and mucocutaneous leishmaniasis are reported, chiefly from the interior forests and savannah areas.

Lymphatic filariasis is reported.

There are sporadic cases of mosquito-borne encephalitis, including Eastern, Western, and St. Louis encephalitis, as well as Mayaro virus.

HIV (human immunodeficiency virus) infection is reported, but travelers are not at risk unless they have unprotected sexual contacts or receive injections or blood transfusions.

For in-depth public health information, go to the Pan-American Health Organization country profile and the Pan-American Health Organization regional office in Guyana.

Do not drink tap water unless it has been boiled, filtered, or chemically disinfected. Do not drink unbottled beverages or drinks with ice. Do not eat fruits or vegetables unless they have been peeled or cooked. Avoid cooked foods that are no longer piping hot. Cooked foods that have been left at room temperature are particularly hazardous. Avoid unpasteurized milk and any products that might have been made from unpasteurized milk, such as ice cream. Avoid food and beverages obtained from street vendors. Do not eat raw or undercooked meat or fish, including ceviche. Some types of fish may contain poisonous biotoxins even when cooked. Barracuda in particular should never be eaten. Other fish that may contain toxins include red snapper, grouper, amberjack, and sea bass.

All travelers should bring along an antibiotic and an antidiarrheal drug to be started promptly if significant diarrhea occurs, 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 accompanied by nausea, vomiting, cramps, fever or blood in the stool. Antibiotics which have been shown to be effective include ciprofloxacin (Cipro), levofloxacin (Levaquin), rifaximin (Xifaxan), or azithromycin (Zithromax). Either loperamide (Imodium) or diphenoxylate (Lomotil) should be taken in addition to the antibiotic to reduce diarrhea and prevent dehydration.

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, medical attention should be sought.

Wear long sleeves, long pants, hats and shoes (rather than sandals). Apply insect repellents containing 25-50% DEET (N,N-diethyl-3-methylbenzamide) or 20% picaridin (Bayrepel) to exposed skin (but not to the eyes, mouth, or open wounds). DEET may also be applied to clothing. Products with a lower concentration of either repellent need to be repplied more frequently. Products with a higher concentration of DEET carry an increased risk of neurologic toxicity, especially in children, without any additional benefit. Do not use either DEET or picaridin on children less than two years of age. For additional protection, apply permethrin-containing compounds to clothing, shoes, and bed nets. Permethrin-treated clothing appears to have little toxicity. Don't sleep with the window open unless there is a screen. If sleeping outdoors or in an accomodation that allows entry of mosquitoes, use a bed net, preferably impregnated with insect repellent, with edges tucked in under the mattress. The mesh size should be less than 1.5 mm. If the sleeping area is not otherwise protected, use a mosquito coil, which fills the room with insecticide through the night.

Bring adequate supplies of all medications in their original containers, clearly labeled. Carry a signed, dated letter from the primary physician describing all medical conditions and listing all medications, including generic names. If carrying syringes or needles, be sure to carry a physician's letter documenting their medical necessity.Pack all medications in hand luggage. Carry a duplicate supply in the checked luggage. If you wear glasses or contacts, bring an extra pair. If you have significant allergies or chronic medical problems, wear a medical alert bracelet.

Make sure your health insurance covers you for medical expenses abroad. If not, supplemental insurance for overseas coverage, including possible evacuation, should be seriously considered. If illness occurs while abroad, medical expenses including evacuation may run to tens of thousands of dollars. For a list of travel insurance and air ambulance companies, go to Medical Information for Americans Traveling Abroad on the U.S. State Department website. Bring your insurance card, claim forms, and any other relevant insurance documents. Before departure, determine whether your insurance plan will make payments directly to providers or reimburse you later for overseas health expenditures. The Medicare and Medicaid programs do not pay for medical services outside the United States.

Pack a personal medical kit, customized for your trip (see description). Take appropriate measures to prevent motion sickness and jet lag, discussed elsewhere. On long flights, be sure to walk around the cabin, contract your leg muscles periodically, and drink plenty of fluids to prevent blood clots in the legs. For those at high risk for blood clots, consider wearing compression stockings.

Avoid contact with stray dogs and other animals. If an animal bites or scratches you, clean the wound with large amounts of soap and water and contact local health authorities immediately. Wear sun block regularly when needed. Use condoms for all sexual encounters. Ride only in motor vehicles with seat belts. Do not ride on motorcycles.

For an ambulance in Guyana, call 913, but ambulances may not be fully equipped and may not always be available.

Medical facilities in Guyana are extremely limited. Specialists may not be fully trained, hospitals may not be adequately staffed or equipped, and sanitation may be poor. St. Joseph's Mercy Hospital is a private facility located next to the U.S. Embassy at 130-132 Parade St., Kingston, Georgetown (tel. 592-227-2072/5; website http://www.mercy.hospital.org.gy/). Equipment is basic, but it has 124 beds, a 24-hour emergency room, and an intensive care unit with four beds. Another option is Davis Memorial Hospital (121 Durban Backlands Lodge, Georgetown; tel. 592-227-2041, 2042), which is run by the Seventh-Day Adventist Church.

For a guide to other medical resources in Guyana, including various medical specialists, go to the U.S. Embassy website at http://georgetown.usembassy.gov/guyana/citizen_services/medical_info.html. Most doctors and hospitals will expect payment in cash, regardless of whether you have travel health insurance. Serious medical problems will require air evacuation to a country with state-of-the-art medical facilities.

Supplies of certain pharmaceuticals may be limited. Travelers should be sure to bring along an adequate supply of all prescription medications. There are pharmacies at St. Joseph's Mercy Hospital (130-132 Parade St., Kingston, Georgetown; tel. 592-227-2072/5) and Davis Memorial Hospital (121 Durban Backlands Lodge, Georgetown; tel. 592-227-2041, 2042).

Make sure you have the names and contact information for qualified medical personnel before you go abroad (see the U.S. Embassy website).

In general, the recommendations for infants and young children are the same as those for adults, except that certain vaccines and medications should not be administered to this age group. Most importantly, yellow fever vaccine is not approved for use in those under age nine months. Unless there is an extraordinary need to do so, children less than nine months of age should not be brought to Guyana.

The recommendations for malaria prophylaxis are the same for young children as for adults, except that (1) dosages are lower; (2) Malarone is not recommended for children weighing less than 25 pounds; and (3) doxycycline should be avoided. DEET-containing insect repellents are not advised for children under age two, so it's particularly important to keep children in this age group well-covered to protect them from mosquito bites.

Food and water precautions, which are recommended for all travelers, must be strictly followed at all times, because diarrhea is especially dangerous in this age group and because the vaccines for hepatitis A and typhoid fever are not approved for children less than two years of age.

All children should be up-to-date on routine childhood immunizations, as recommended by the American Academy of Pediatrics. Children who are 12 months or older should receive a total of 2 doses of MMR (measles-mumps-rubella) vaccine, separated by at least 28 days, before international travel. Children between the ages of 6 and 11 months should be given a single dose of measles vaccine. MMR vaccine may be given if measles vaccine is not available, though immunization against mumps and rubella is not necessary before age one unless visiting a country where an outbreak is in progress. Children less than one year of age may also need to receive other immunizations ahead of schedule (see the accelerated immunization schedule).

Pregnant women should not in general travel to Guyana, because yellow fever vaccine, which is strongly recommended for all parts of the country, is not recommended for use during pregnancy.

Helpful maps are available in the University of Texas Perry-Castaneda Map Collection and the United Nations map library. If you have the name of the town or city you'll be visiting and need to know which state or province it's in, you might find your answer in the Getty Thesaurus of Geographic Names.

Americans living in or visiting Guyana are encouraged to register at the Consular Section of the U.S. Embassy in Georgetown and obtain updated information on travel and security within Guyana. The U.S. Embassy is located at 100 Young and Duke Streets, telephone 011-592-225-4900 through 54909, fax 011-592-225-8497. Hours of operation are Monday-Friday, 7:30 am to 4:00 pm, except local and U.S. holidays. For emergencies after hours, on weekends and on holidays, U.S. citizens are requested to call the U.S. Embassy duty officer at 011-592-226-2614 or 226-8298 or 227-7868 and to leave a message for pager number 6516.

For information on safety and security, go to the U.S. Department of State, United Kingdom Foreign and Commonwealth Office, Foreign Affairs Canada, and the Australian Department of Foreign Affairs and Trade.