This serious illness is caused by contaminated food or water and is characterized by severe diarrhea, often with blood or mucus in the stool.
There are two kinds of dysentery. Bacillary dysentery(shigellosis) is characterized by a high fever and rapid onset; headache, vomiting and stomach pains are also symptoms. It generally does not last longer than a week, but it is highly contagious.
Amebic dysentery is often more gradual in the onset of symptoms, with cramping abdominal pain and vomiting less likely; fever may not be present. It is not a self-limiting disease: it will persist until treated and can recur and cause long-term health problems. A stool test is necessary to diagnose which kind of dysentery you have, so you should seek medical help urgently. In case of an emergency the drugs norfloxacin or ciprofloxacin can be used as presumptive treatment for bacillary dysentery, and metronidazole (Flagyl) for amebic dysentery.
Typhoid fever is an acute bacterial disease caused by Salmonella typhi. Typhoid germs are passed in the feces and, to some extent, the urine of infected people. The germs are spread by eating or drinking water or food contaminated by feces (or urine) from the infected individual.
Symptoms generally appear one to three weeks after exposure. In its early stages typhoid resembles many other illnesses, and often sufferers may feel like they have a bad cold or flu on the way. The onset of typhoid fever is normally gradual, with fever, malaise, chills, headache, generalized aches in the muscles and joints, tiredness, loss of appetite, and sore throat. Abdominal pain and distension may occur. Vomiting, which may occur toward the end of the first week, is not usually severe. Diarrhea is infrequent; constipation occurs more often than diarrhea.
A fever develops which rises a little each day until it is around 104 degrees Fahrenheit or more. The person's pulse is often slow relative to the degree of fever present and gets slower as the fever rises, unlike a normal fever where the pulse increases.
In the second week, the high fever and slow pulse continue and a few pink spots may appear on the body. Trembling, delirium, weakness, weight loss and dehydration are other symptoms. "Pea soup" diarrhea may occur. Abdominal pain and distension may be increased. If there are no further complications, the fever and other symptoms will slowly diminish during the third week. However, typhoid is a very dangerous infection and an infected individual must get medical help as soon as possible, because pneumonia or peritonitis (perforated bowel) are common complications.
Diagnosis comes from isolation of Salmonella typhi from the blood or stool of an infected person.
The best protection is to avoid consuming food or water that may be contaminated. For foreign travelers, drinking only boiled water or carbonated beverages and eating only cooked food, lowers the risk of infection.
The fever should be treated by keeping the victim cool, and dehydration should also be watched for. Treatment is with ampicillin, chloramphenicol, Bactrim, or Cipro, depend ing upon the clinical circumstances. Chloramphenicol is the most effective drug for treatment of the acute illness, if the organism is not resistant. If hospital facilities are not close by, consider starting treatment with Cipro. Ampicillin and amoxicillin are effective alternatives.
Fatalities are less than 1 percent with antibiotic treatment. Even after effective treatment, you may continue to carry typhoid bacteria in your intestinal tract, which can be passed to close contacts such as family members. Follow-up testing is very important. Relapses are common, and the frequency of relapse does not appear to have been changed dramatically by antibiotic therapy.
Vaccines are available that afford significant protection. Currently available vaccines have been shown to protect 70% - 90% of the recipients. Therefore, even vaccinated travelers should be cautious in selecting their food and water.
The oral vaccine consists of 4 capsules containing live attenuated bacteria. They are taken every other day for seven days. The oral vaccine is effective for travelers to infected areas for five years. The entire 4 doses should be repeated every 5 years if the person is at continued risk. Reactions are rare and include nausea, vomiting, abdominal cramps, and skin rash.
The injectable vaccine consists of a primary series of two shots, spaced at least 4 weeks apart. A booster dose given every 3 years provides continued protection for repeated exposure. If there is insufficient time for two doses a month apart, an accelerated schedule of three shots a week apart may be administered. The accelerated schedule may be less effective.
CDC recommends a typhoid vaccination for those travelers who are going off the usual tourist itineraries, traveling to smaller cities and rural areas, or staying for six weeks or more. Typhoid vaccination is not required for international travel.
HIV / AIDS
Acquired Immune Deficiency Syndrome (AIDS) is caused by infection with the Human Immunodeficiency Virus (HIV). HIV destroys the body's immune system, which means that the body can no longer successfully fight against certain infections and some forms of cancer.
AIDS is a global problem. It is estimated that more than six to eight million people are now infected with the HIV virus. Sex workers are frequently infected: the proportion infected exceeds 80% in many parts of the world, and the current stated average population infection rate in Africa is one in 40.
Human immunodeficiency virus (HIV) which causes acquired immunodeficiency syndrome or AIDS is found primarily in blood, semen, and vaginal secretions of an infected person. HIV is spread by sexual contact with an infected person, by needle-sharing among injecting drug users, and through transfusions of infected blood and blood clotting factors. Babies born to HIV-infected mothers may have the disease.
In the United States blood is screened for HIV antibodies, but this screening may not take place in all countries. Scientific studies have revealed no evidence that HIV is transmitted by air, food, water, insects, inanimate objects, or casual contact. Even though HIV antibodies are normally detected on a test within 6 months after infection, the period between infection and development of disease symptoms (incubation period) may be 10 years or longer. Treatment has prolonged the survival of some HIV infected persons, but there is no known cure or vaccine available.
AIDS is found throughout the world. The risk to a traveler depends on whether the traveler will be involved in sexual or needle-sharing contact with a person who is infected with HIV. Receipt of unscreened blood for transfusion poses a risk for HIV infection.
Most everyday activities pose no risk of HIV transmission. Normal social contact, swimming in public pools, eating in restaurants and using public toilets are not dangerous. There is no scientific evidence to suggest that mosquitoes transmit HIV.
Avoiding casual unprotected sexual contacts is the best solution. Other than this, condoms are a reasonable barrier. However, if petroleum lubricants are used, condoms are liable to break as petroleum products attack latex. Also, locally produced condoms can often be poor quality and are not recommended.
Never use needles or syringes that have been used by others. When receiving medical attention, always insist that unused, disposable equipment or fully sterilized material is used. If you do need an injection, ask to see the syringe unwrapped in front of you, or better still take a needle and syringe pack with you overseas - it is a cheap insurance package against infection with HIV. Never use another person's razor or toothbrush. Don't have parts of your body pierced, or allow yourself to be tattooed.
HIV/AIDS can be spread through infected blood transfusions. Most developing countries cannot afford to screen blood for transfusions.
No effective vaccine has been developed for HIV.
Cholera is an acute intestinal diarrheal disease caused by a bacterium -- Vibrio cholerae, which is found in water contaminated by sewage. Cholera occurs both sporadically and in large, abrupt epidemics.
An epidemic of cholera started in South America in 1991, and has swept through Central and South America since then. Cholera cases were first recognized in Peru in the last week of January 1991. The majority of cases have been reported from Peru, Ecuador, Colombia, Guatemala, and Mexico. Cholera has been reported in coastal cities and inland areas of most of these countries. Cholera has also been reported in Cuzco in Peru and in the Galapagos Islands of Ecuador. Other countries to report cases include Argentina, Belize, Bolivia, Brazil, Chile, Costa Rica, El Salvador, French Guiana, Guyana, Honduras, Nicaragua, Panama, Suriname, and Venezuela. Bolivia has reported cases as well. Cholera has been reported from five states in Brazil. Several municipalities near the mouth of the Amazon River have been affected. Cholera has been reported in a small number of US residents traveling to Peru and Ecuador.
The risk of infection to the US traveler is very low, especially those that are following the usual tourist itineraries and staying in standard accommodations. Cholera germs account for only a small percentage of all cases of travelers' diarrhea. Very few Western travelers ever get seriously ill from cholera. In fact, the disease is reported in only 1 in 500,000 returning travelers. Most illness occurs in native people who are malnourished and who ingest large amounts of bacteria from heavily contaminated water. Travelers should consider the vaccine if they have any problems with their stomach, such as anti-acid therapy, ulcers, or if they will be living in less than sanitary conditions in areas of high cholera activity.
Predicting how long the epidemic in Latin America will last is difficult. The cholera epidemic in Africa has lasted more than 20 years. In areas with inadequate sanitation, a cholera epidemic cannot be stopped immediately, and there are no signs that the epidemic in the Americas will end soon.
Latin American countries that have not yet reported cases are still at risk for cholera in the coming months and years. Major improvements in sewage and water treatment systems are needed in many of these countries to prevent future epidemic cholera.
The clinical picture of cholera varies widely. The illness in healthy tourists is usually very mild because they rarely ingest the heavily contaminated water necessary to trigger the disease. Severe cases usually strike only the indigenous population. 1 in 20 infected persons gets severe disease. The cholera germs grow in the small intestine and produce an intestinal toxin that can cause a massive outpouring of water and salt into the gut. The toxin does not cause physical damage to the intestinal wall.
There is an abrupt onset of voluminous watery diarrhea, dehydration, vomiting, and muscle cramps. The onset of the diarrhea is painless and explosive, and several liters of fluid may be lost every hour. The rapid loss of salt and water in the stools can cause severe, life-threatening dehydration. The frequent, watery stools soon lose all fecal appearance and odor ("rice water stools"). The diarrhea is not bloody and there is no fever. Vomiting generally occurs but is not associated with nausea.Without treatment, death can occur within hours. Death from dehydration can occur in up to 50% of untreated cases.Cholera must be distinguished from other causes of travelers' diarrhea caused by E. coli, Shigella, Salmonella, viruses, and parasites. The lack of blood, mucus, or pus in the stools of cholera victims is a distinguishing feature.
Managing the effects of dehydration is the mainstay of treatment. If you can drink sufficient fluids, you can prevent serious dehydration. Oral rehydration solutions are essential, and their prompt use has saved many lives. (The World Health Organization rehydration formula is prepared by adding one packet to one liter of safe drinking water. Individuals should drink 6 to 8 ounces, or more, after every loose stool.) If the diarrhea is very profuse and exceeds what individuals can drink, or if they are vomiting and can't drink, hospitalization and intravenous therapy will be necessary.
If there is an appreciable delay in getting to a hospital, then tetracycline should be taken. The adult dose is 250 mg four times daily. It is not recommended for children aged eight years or under, nor for pregnant women, because tetracycline stains the developing teeth of fetuses and children. An alternative drug is Ampicillin. While antibiotics might kill the bacteria, it is the toxin produced by the bacteria which causes the massive fluid loss. Fluid replacement is by far the most important aspect of treatment. In the hospital, antibiotics such as Furoxone, tetracycline, Cipro, or Bactrim will shorten the duration of illness and are important adjuncts to hydration therapy.
Travelers to cholera infected areas should follow the standard food and water precautions of eating only thoroughly cooked food, peeling their own fruit, and drinking either boiled water, bottled carbonated water, or bottled carbonated soft drinks.
Following these simple rules, will help you avoid most food and water borne diseases:
*Drink only water that you have boiled or treated with chlorine or iodine.
Other safe beverages include tea and coffee made with boiled water and
carbonated, bottled beverages with no ice.
*Eat only foods that have been thoroughly cooked and are still hot, or fruit
that you have peeled yourself.
*Avoid undercooked or raw fish or shellfish, including ceviche.
*Make sure all vegetables are cooked.
*Avoid all salads.
*Avoid foods and beverages from street vendors.
*A simple rule of thumb -- Boil it, cook it, peel it, or forget it.
The available vaccine is only 50% effective in reducing the illness, and is not recommended routinely for travelers. The primary series is normally two injections with booster doses given every 6 months for persons who remain at high risk. Cholera vaccine is not recommended for infants under 6 months old, or for pregnant women.
If you are exposed, the vast majority of cholera germs that you ingest will be destroyed in your stomach by gastric acid. The cholera vaccine offers little protection and is no longer officially recommended by the World Health Organization. The antibodies produced by the vaccine have little effect upon the germs in your intestine. Marginal benefit from vaccination may occur in those travelers with (1) low-protective gastric acid levels (e.g., people taking anti-ulcer drugs) and (2) those on long-term assignment in high-risk areas where there is poor sanitation and the possibility of exposure to heavily contaminated water. Otherwise, the only indication for the vaccine is to satisfy the entry requirements of certain countries.
Poliomyelitis is a highly contagious infection caused by poliovirus, which is transmitted from person to person through exposure to fecal material or respiratory secretions containing the virus. The incubation period ranges from nine to twelve days. Most poliovirus infections are asymptomatic.
Initial symptoms, when they occur, are similar to those of other viral infections and may include fever, headache, muscle aches, malaise, nausea, vomiting, and sore throat. In roughly one in a thousand cases, poliovirus attacks the spinal cord or brainstem, leading to paralysis in various parts of the body, most often the legs.
Polio mainly affects children under three years of age.
All children should receive four doses of inactivated polio vaccine at ages 2 months, 4 months, 6-18 months, and 4-6 years. An accelerated immunization schedule is recommended for children who have not completed their polio immunizations and who may be traveling to places where polio still occurs.
Adults who will be traveling to an area where polio is reported and who have never been immunized or whose immunization status is unknown should be given a total of three doses of inactivated polio vaccine separated by at least 4 weeks from each other. Adults who completed the full childhood series of polio immunizations but never had a booster as an adult may be given a single dose of inactivated polio vaccine before entering a polio-endemic area.
Inactivated polio vaccine has essentially replaced oral polio vaccine in the United States because the latter may cause paralytic poliomyelitis, though this is rare. Oral polio vaccine is recommended only for unvaccinated children who will be traveling in less than four weeks to an area where polio is endemic and for mass vaccination campaigns to control polio outbreaks.
In 2000, there were fewer than 3500 reported polio cases worldwide. Tens of thousands more children are infected with the virus; while they do not suffer paralysis, they can infect other children.
Polio has been eradicated in the Americas, except for a small outbreak in the Dominican Republic and Haiti in late 2000 which appears to have been controlled. In October 2000, the World Health Organization certified that the Western Pacific region, which includes large parts of Southeast Asia as well as the Pacific Islands, was polio-free. In Europe, only Turkey continues to report a small number of cases. Poliovirus transmission continues to occur in the Indian subcontinent and sub-Saharan Africa, as well as certain countries in the Middle East.Travelers to countries where poliomyelitis is epidemic or endemic are considered to be at increased risk of poliomyelitis and should be fully immunized.
In general, travelers to developing countries (excluding countries in Latin America) should be considered to be at increased risk of exposure to wild poliovirus.
Unvaccinated, or partially vaccinated travelers should complete a primary series with the vaccine that is appropriate to their age and previous immunization status.
Persons who have previously received a primary series may need additional doses of a polio vaccine before traveling to areas with an increased risk of exposure to wild poliovirus.
Malaria is a serious parasitic infection that is transmitted to humans through the bite of an infected Anopheles mosquito. These mosquitoes are present in almost all countries in the tropics and subtropics. Anopheles mosquitoes bite during evening and nighttime hours, from dusk to dawn. Both personal protection measures and anti malarial drugs are recommended for travelers who have exposure during evening and nighttime hours in malaria risk areas.
Symptoms of malaria include fever, chills, headache, muscle ache, and malaise. Early stages of malaria may resemble the onset of flu. Travelers who become ill with a fever during or after travel in a malaria risk area should seek prompt medical attention and should inform their physician of their recent travel history. Neither the traveler nor the physician should assume that the traveler has the flu or some other disease without doing a laboratory test to determine if the symptoms are caused by malaria.
Travelers can still get malaria despite the use of preventive measure. Malaria symptoms can develop as early as 7 days after being bitten by an infected mosquito or as late as several months after departure from a malarious area, after anti malarial drugs have been discontinued. Malaria can be treated effectively in its early stages, but delaying treatment can have serious consequences. If left untreated, malaria can cause anemia, kidney failure, coma, and death. In spite of all protective measures, travelers occasionally develop malaria. Therefore, while traveling and up to one year after returning home, travelers should seek medical evaluation for any flu-like symptoms.
Malaria transmission occurs primarily between dusk and dawn. The risk of malaria depends on the traveler's itinerary, the duration of travel, and the place where the traveler will spend the evenings and nights. Protective measures include remaining in well-screened areas, using mosquito nets, and wearing protective clothes that cover most of the body. Insect repellent should be used on exposed skin. The most effective repellents contain DEET. The effect should last for about 4 hours. Travelers should use pyrethroid-containing flying insect spray in living and sleeping areas during evening and nighttime hours. Permethrin (Permanone) may be sprayed on clothing for protection against mosquitoes. When used according to directions, Permethrin will repel insects from clothing for several weeks.
Travelers at risk for malaria should take Mefloquine tablets to prevent the disease. Mefloquine should be taken one week before leaving, weekly while in the malarious area, and weekly for 4 weeks after leaving the malarious area. Chemoprophylaxis may also include Fansidar drugs depending on the area to be visited and the absence or existence of resistant strains of malaria.
Malaria occurs in large areas of Central and South America, Hispaniola, sub -Saharan Africa, the Indian subcontinent, Southeast Asia, the Middle East, and Oceana. The risk of exposure is less in urban areas and during the daytime, and greater in rural areas and during the evening and nighttime hours. The risk of acquiring malaria is greater in Africa since travelers to Africa tend to spend considerable time, including evening and nighttime hours, in rural areas where malaria risk is highest.
Chloroquine/mefloquine-sensitive malaria occurs in: Mexico, Central America, far north Argentina, Paraguay, Egypt, Turkey, Syria, Lebanon, Iraq, Saudi Arabia, Kuwait, United Arab Emirates, Quatar, Bahrain.
Chloroquine/melfoquine-resistant P. falciparum malaria occurs in: Brazil, Peru, Equador, Columbia, Venezuela, Guyana, Surinam, French Guiana, Bolivia, throughout sub-Saharan, West, Central, East, and southern Africa, including Madagascar, in Yemen, Oman, Iran, Afghanistan, all of South Asia, all of Southeast Asia including Indonesia, Philippines, and southern China.
Resistance to both chloroquine and Fansidar is widespread in Thailand, Burma, Cambodia, and the Amazon basin area of South America, and resistance has also been reported in sub-Saharan Africa. Resistance to mefloquine has been confirmed in Thailand along the borders with Cambodia and Burma.
Worms are parasites common in rural, tropical areas.
They can be present on unwashed vegetables or in undercooked meat and you can pick them up through your skin by walking in bare feet. Infestations may not show up for some time, and although they are generally not serious, if left untreated they can cause severe health problems.A stool test is necessary to pinpoint the problem and medication is often available over the counter.
Tetanus, also known as lockjaw, is an infection caused by wounds contaminated by Clostridia bacteria, a germ which lives in the feces of animals and people. It occurs worldwide.
It is important to clean all cuts, punctures or animal bites.
The first symptom of the disease may be discomfort in swallowing or stiffening of the jaw and neck; this is followed by painful convulsions of the jaw and whole body, and death.
The disease is preventable with a vaccination, and then a booster given every 10 years.
Hepatitis A is an enterically transmitted viral disease, highly endemic throughout the developing world, where standards of sanitation are poor. In developing countries, hepatitis A virus (HAV) is usually acquired during childhood. Most frequently the children either are asymptomatic or they develop mild infections, resulting in the development of life-long immunity.
Transmission may occur by direct person-to-person contact, from contaminated water, ice, or shellfish harvested from sewage-contaminated water, or from fruits, vegetables or other foods which are eaten uncooked, but which may become contaminated during handling.
Symptoms include fatigue, fever, loss of appetite, nausea, dark urine, jaundice, vomiting, aches and pains, and light stools. No specific therapy is available.
For travelers to developing countries, risk of infection increases with the duration of travel, and is highest for those who live in or visit rural areas, trek in back country, or frequently eat or drink in settings of poor sanitation.
Travelers are at high risk for Hepatitis A, especially if travel plans include visiting rural areas and extensive travel in the countryside, frequent close contact with local persons, or eating in settings of poor sanitation.
A study has shown that many cases of travel-related hepatitis A occur in travelers to developing countries with "standard" itineraries, accommodations, and food consumption behaviors.
In developing countries, travelers should minimize their exposure to hepatitis A and other enteric diseases by avoiding potentially contaminated water or food. Travelers should avoid drinking water (or beverages with ice) of unknown purity and eating uncooked shellfish or uncooked fruits or vegetables that are not peeled or prepared by the traveler.
Hepatitis A virus is inactivated by boiling or cooking to 185°F or 85° C for 1 minute, therefore eating thoroughly cooked foods and drinking only treated water serve as general precautions. Cooked foods may serve as vehicles for disease if they are contaminated after cooking. Adequate chlorination of water as recommended in the U.S. will inactivate HAV.
This is a very infectious virus, so if there is risk of exposure, injection with gammaglobulin (IG) or vaccination with Havrix -- the hepatitis A vaccine currently licensed for use in the US -- is recommended. Gammaglobulin is an injection of antibodies to hepatitis A, providing immunity for a limited time. Havrix is a vaccine which causes the traveler to develop his or her own antibodies, giving long-lasting immunity.
Hepatitis A vaccine is recommended for persons who plan to travel repeatedly or reside for long periods of time in intermediate or high risk areas. Immune globulin should be used for travelers under 2 years of age, and is recommended for any person who desires only short term protection.
CDC recommends hepatitis A vaccine or IG for protection against hepatitis A. For travelers over 18 years of age, hepatitis A vaccine should be given in a two dose series with the second dose administered 6-12 months after the first. For children and adolescents (2-18 years), a three dose series of hepatitis A vaccine is recommended; the second dose is given 1 month after the first dose and the third dose 6-12 months after the first dose.
Travelers can be considered to be protected four weeks after receiving the initial vaccine dose. IG should also be given if vaccine is administered less than four weeks before travel. The vaccine series must be completed for long-term protection.