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ADDENDUM UPDATE Dear Christos: I recently attended a hepatitis seminar with some world experts in liver diseases who managaed to convince me to alter my initial recommendations of the hepatitis A virus (HAV) vaccine to you and your family. They described a condition of fulminant hepatitis A (FHA), which you can think of "active explosive-lethal" HAV that can occur when you contract the HAV. This can lead to death if untreated, but if you're lucky to detect the disease early and happen to live near a big city you can be treated with chemotherapy and a liver transplant. The incidence of FHA is rare but real enough to warrant some serious consideration in giving the HAV vaccine when travelling abroad. Age (in years) Incidence of FHA If you already have some other viral hepatitis or other chronic liver disease, then this incidence increases accordingly. So, the recommendations are to definitely give the HAV vaccine to any traveler going to areas of endemic disease. These areas of the highest prevalence of HAV worldwide, which definietly require the HAV vaccine are (Central and South America, all of Africa, Middle-East, India, Indonesia, the Far-East, China, the Phillipines and Greenland). The areas of Intermediate HAV prevalence include: (all of the former Soviet Union, and Eastern Mediterranean Europe). The lowest prevalence areas are North America, Australia and Western Europe. So where does that leave us? Well these are the recommendations for travelers. If you're making a single trip of less than 2-3 months duration, then give either the active vaccine or the passive immune globulin. If your making multiple trips, then it's straight forward, you should be vaccinated with the active HAV. Ideally, the first dose would be given 1 month before the trip. If there is insufficient time, the vaccine can be given with immune globulin, but the immune globulin may reduce the effectiveness (immunogenicity) of the vaccine. Passive Immunization: Immune Globulin (IG) should be given to anyone who has contact with someone with the active HAV. It must be administered ASAP and no latter than 14 days. It has little or no effect if given after 2 weeks, which is the incubation period of the HAV. This offers the advantage of immediate protection but the duration of protection is variable from 2 to 6 months. The effectiveness of this vaccine is dependent on the amount of IG that you receive as well as the timing of administration. The recommended dose is 0.02 ml/kg. In Ontario IG is not readily available in regualr pharmacies. You have to go to certain hospital dispensing pharmacies or even the Red Cross Laboratory itself. Active Immunization: In North America this is really the way to go. There are 2 commercially available Hepatitis A vaccines available in Canada. One is called Havrix, made by SmithKline Beecham and the other is called Vaqta made by Merck Pharmaceutical. Both of these vaccines are very similar and virtually identical. There is no reason to choose one over the other. Both are made from formalin inactivated viral particles from infected fibroblast cell lines. Both are very well tolerated with the frequency of side effects very low, similar to the hepatitis B vaccine. Both formulations may contain residual amounts of formaldehyde, 2-phenoxyethanol and the antibiotic neomycin. Both involve 2 doses of 0.5ml each, the second dose given 6 - 12 months after the first. If the second dose is missed, then it can be given at any time without repeating the first dose. After the second dose of vaccine the duration of protection may persist for at least 20 years. This high response rate makes routine blood (serologic) testing after vaccination unnecessary. These vaccines must be stored between 2'C and 8'C and should not be frozen to preserve their effectiveness. Both vaccines must be given by needle injection (intramuscularlay) preferably in the shoulder (deltoid). Summary So, Christos, I hope you haven't yet left for Greece. If you have and do come in contact with an active HAV person, then by hook or by crook get some IG passive vaccine ASAP within the 14 day threshold time of contact. Otherwise you're out of luck and should just hope you're not unfortunate enough to develop FHA. Since Greece is considered an intermediate prevalence country of the HAV, then it's more of a judgement call whether you should or shouldn't get the vaccine. I would tend to recommend the vaccine in your situation. If you're about to embark on your summer trip, then get both the active vaccine and IG for the reasons stated above. If you're leaving later than a month from now, then get the full 2 doses of the active vaccine (either the Havrix or the Vaqta) once now, and repeated again in a months time. Remember, the major reason for giving the vaccine is not so much to prevent the occurrence of hepatitis A, which is not that big a deal, and usually tends to be a self-limiting illness as previously described. Rather, we're giving the vaccine to prevent that rare but real (and costly $300,000.00 cost per liver transplant) risk of developing that lethal fulminant hepatitis A if you do happen to get the HAV virus. The same recommendations and guidelines apply to your children, unless they're less than 1 year old in which case the safety of the active vaccine has not been established and should be avoided. In this instance it is safe to give the infant IG if warranted. Regardless of what you and your physician decide, do remember that prevention
is the key as I cannot overemphasize the importance of hygiene, paying
particular attention in rural areas to the quality of food and water.
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