All Travelers read this

Bob Young MD

119 North Milpas Street

Santa Barbara, CA 93103

Office (805) 963-1824 Fax (805) 963-1826 Web address www.bobyoungmd.com

The information that follows is important for anyone traveling to underdeveloped regions of the world. These health problems exist in all of these areas and will not be going away. Therefore, the information that follows is important for all travlers to these regions, irrespective of 'style', duration, or season of travel. They should be given serious consideration by all travelers.

Hepatitis A: Hepatitis A is pretty much an issue in all parts of the underdeveloped world. Even in more developed countries such as the United States Hepatitis A is a significant problem. More and more it is being included in immunizations unrelated to travel. The infection is contracted from impure water and, indirectly, through contaminated food. In regions of the world where the water sanitation and purification systems are suboptimal Hepatitis A becomes a more common and greater risk. Since about 1995 an effective vaccine protecting against Hepatitis A has been available. Prior to that, travelers were confronted with the unpleasant experience of a large, relatively painful injection of immune globulin (gammaglobulin) in the buttock. To make matters worse, this injection was only effective for about three to six months and needed to be repeated whenever a person commenced a new journey into a hepatitis risk region of the world. The current Hepatitis A vaccine is vastly superior to the immunoglobulin injection. For complete protection the series consists of two injections spaced six to 12 months apart. Since it is very seldom that a traveler will see a physician more than six months prior to a journey generally all they receive for this initial visit is the first dose of the vaccine. This single injection provides a good deal of protection, probably in the range of about 80%. In an optimal situation the traveler would return for the second injection six to 12 months after the first. Frequently, however, the second injection is given before the next journey takes place. This might be several years later. The current medical thinking is that after completion of the two shot series immunity from Hepatitis A is lifetime. In fact, there is a high incidence of immunity to hepatitis A that exists in the US if he population even without the vaccine. It is estimated, based on laboratory testing, that approximately 50% of Americans over the age of 50 have been previously exposed to this infection. The test for hepatitis antibody costs about as much as the vaccine itself so many travelers just opt to receive the Hepatitis A vaccine without testing for prior exposure. The severity of Hepatitis A can range from a very mild condition where a person may not even necessarily feel very sick all the way through fulminating disease which can result in death. In any event, protection against Hepatitis A is important for any travelers to underdeveloped parts of the world.

Tetanus: Tetanus is a serious, potentially fatal infection that can occur when the skin is broken and the infecting organism develops in the underlying tissue. Vaccination against Tetanus affords virtually 100% protection. The standard recommendation, if not traveling, is a tetanus booster once every 10 years if there are no wounds or injuries occur. If a skin penetrating injury occurs a tetanus booster will be administered if it has been more than five years since the last vaccination. For travel purposes, a tetanus booster is recommended if it has been greater than five years since the last vaccination. The reason for the five-year, as opposed to a ten year, interval is because of the probable lack of availability or safety of a tetanus vaccine in the less developed parts of the world. Obtaining a tetanus booster shortly before travel the question of "when was your last tetanus shot?" becomes moot. Most of the time, when I ask travelers ‘when was your last tetanus shot?’, they can't remember. Getting a tetanus booster in conjunction with a trip makes it much easier to remember the next time that question is asked. Additionally, it is important to ask that the diphtheria vaccine be given in conjunction with the tetanus booster. Generally the two are combined together (diphtheria-tetanus, abbreviated ‘DT’). There have been outbreaks of diphtheria that occur occasionally in less developed regions of the world. Although unusual, the added protection of the diphtheria component of the vaccine protects against this serious infection. Recently a new form of tetanus vaccine has become available which includes immunization against Pertussis. Adults are often the carrier of Pertussis which is the organism responsible for whooping cough and children. This can also present as a serious infection and in adults and if the DPT (Tetanus-Diphtheria-Pertussis) vaccine is available this is the recommended form.

Hepatitis B: As described above, Hepatitis A is the strain of hepatitis which presents the greatest risk to travelers. The word "hepatitis" means inflammation of the liver. There are a number of viruses which can cause hepatitis, the most prevalent being hepatitis A. Hepatitis B also exists more commonly in less developed regions of the world. In contrast to Hepatitis A, however, Hepatitis B is not transmitted primarily by ingestion of contaminated food or water. Hepatitis B transmission occurs by transfer of body fluids which can include blood transfusions, sexual contact, or injections of any form (including contaminated needles or drug use). For the most part, this type of hepatitis is more associated with lifestyle than region of travel. A higher incidence of hepatitis B in many underdeveloped areas probably correlates with the close living conditions and less opportunity for personal hygiene. Hepatitis B vaccination has been the general standard for many years in the United States. Younger travelers should check their childhood and school immunization records as they very likely have received a complete series of hepatitis B vaccinations (three separate immunizations). As a general safety precaution the hepatitis B vaccine is a good idea for people traveling to less developed parts of the world. The risk of the disease, however, is significantly less than hepatitis A. Whereas hepatitis A is a "don't leave home without it" recommendation, the relative risk of acquiring hepatitis B is significantly less than hepatitis A. The Hepatitis B vaccine series consists of three injections and takes six months to complete but, even if incomplete, can be started before travel. Even a partial series affords a good amount of protection but should be completed upon return. There is a combined form of the hepatitis vaccine which protects against both Hepatitis A and Hepatitis B. The complete of combined Hepatitis A & B series also takes six months. There are occasional questions about another form of hepatitis, hepatitis C. Hepatitis C is a serious infection which is associated with blood transfusion or intravenous drug use. There is no vaccine for hepatitis C.

Polio: Although virtually everyone has received the initial polio vaccination series in childhood, a standard recommendation for travelers to Africa or Asia is a final polio vaccine given as an adult. Polio has been virtually eliminated from the Americas (North and South), Europe, and most developed regions of the world. The disease is still present, however, in the Asian subcontinent and in Africa. Although it is extremely unlikely that a case of polio might develop in someone who has received initial childhood series of vaccines, it can and does rarely occur. I personally received a letter some years ago from a woman who had been traveling in Asia and developed a paralytic form of polio. From her wheelchair she wrote me a letter asking me to please remind travelers to areas where polio still exists to receive a final adult polio booster. This final vaccination provides lifetime immunity. The form of vaccine used is a killed strain and poses no risk of any polio-like complications.

TB Skin test: I recommend that all travelers to underdeveloped parts of the world obtain a TB skin test if they haven't done this in the past five years. There are several reasons for this recommendation. The incidence of tuberculosis is increasing worldwide including the United States. The recently publicized travels of an American with a drug-resistant strain of tuberculosis accentuate the importance of the problem. The TB skin test is not a vaccine but rather serves to identify whether or not a person has been previously exposed to tuberculosis. In most situations this test will be negative. If a person returns from foreign travels and the test has converted to positive this provides valuable information in terms of diagnosis and treatment.

Rabies vaccine – something to know about

Rabies is a condition that most people don't associate with travel. In fact, the reality is, that a person is no more likely, perhaps less likely, to be bitten by a dog in a foreign country than they are at home. Besides that, just because a dog bites a person is still extremely unlikely that that dog did so because it was rabid. Dogs bite people all the time and it is generally because an individual has unknowingly ventured into the territorial space of the animal or that puppies are nearby. Therefore, when considering the importance of rabies pre-exposure vaccination one needs to obviously consider the fact that the real likelihood of being bitten by a rabid animal is extremely low. Nevertheless, there are a number of factors that need to be considered. The real issue is that in most underdeveloped regions of the world, dogs do not have licenses and therefore have not received rabies vaccination. The unfortunate reality is that many of these countries don't have enough funds to vaccinate their own population against common illnesses, much less have vaccines for animals. The reason that it's important to consider pre-exposure rabies vaccination is that, of all the infectious diseases that humans can contract, rabies is perhaps the most devastating. If the virus spreads from the region of the bite to the central nervous system the associated death rate is virtually 100%. For this reason, even though the actual likelihood of acquiring this illness is extremely low, the potentially devastating consequences make it important to at least give consideration.

Although rabies can be transmitted by the bite of any mammal the real issue is dogs. Most animals are fearful of humans and are not aggressive. Dogs represent an exception to this.

Although dog bites are uncommon they are not rare. Furthermore, a dog bite almost

always occurs by accident. Virtually never is somebody bitten because, for example, they were trying to take a puppy away from a mother dog. Usually it is a situation where unknowingly a person has entered the territorial space of a dog or there are puppies nearby. If a person should be bitten by a dog while traveling it is the ultimate rupture of all travel plans. It is essential that a person immediately go to a facility that can provide adequate and proper post-exposure treatment for rabies. In many parts of the world this is virtually impossible. For example, in most parts of equatorial Africa this would involve returning to Europe. In Asia only the largest cities such as Bangkok would be able to provide proper post-exposure treatment. If a person will be traveling in remote locations it can take days to get back to a source of even basic medical attention. Even then, adequate post-exposure treatment might not be available and continued travel could be necessary to obtain proper care. Obviously this represents almost the ‘worst possible case’ but nevertheless it should be given consideration.

If one reads the official literature on recommendations for rabies pre-exposure vaccine (from publications like the Center for Disease Control or World Health Organization) it basically states that if one anticipates being in an endemic area for a month or longer that rabies pre-exposure immunization series should be obtained. In fact, there is nothing special about one month. It's just that the likelihood of a dog bite, much less the bite from a rabies infected animal, is still extremely low that at some point it becomes a mathematical improbability that would justify the expense and trouble of obtaining a pre-exposure vaccine series. For example, if someone were going to Nairobi to deliver a speech at a major hotel and then turn around and leave the country the likelihood of a dog bite occurring in disarray similar type of situation is virtually nil. If this is the lowest risk type of situation the likelihood to go up from this point. There are two groups that are particularly vulnerable to dog bites. These are young children and persons riding bicycles. In general, the more adventurous the trip and the longer the period of time spent in a area of potential risks, the greater the importance of the rabies pre-exposure vaccine series. A situation that applies to younger travelers in general is that, during their lifetime, they will very likely be numerous trips into underdeveloped regions of the world where rabies presents a potential risk. Whereas it used to be that young people would go to somewhere like Fort Lauderdale for Easter vacation now it is not unusual for them to travel to a much more remote location such as Africa or Asia. Prior to the introduction of long distance high-speed air travel it was unlikely that people would spend a significant amount of time in areas of the underdeveloped world and increased risk of infection such as rabies. This is no longer the case. With increased tourism and business travel people will increasingly be venturing into regions of the world where rabies presents a real risk. Furthermore, the situation in a come up repeatedly with the questions about the need for rabies preexposure vaccine being consider each time. In many respects it is probably better to go ahead and get the vaccine series out of the way so that the question doesn't need to be raised every time a trip into an underdeveloped part of the world is planned.

The negative aspect of rabies pre-exposure vaccination, in most cases, is the cost. The vaccine is made in France and must be imported through especially licensed suppliers in the US.

This represents the basic information related to rabies vaccination. Ultimately the decision must be made by each individual traveler. If you have further questions regarding the above material please ask Dr. Young.