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Dysentery

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

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

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.