The risk of Hepatitis A for Travelers

The term hepatitis means inflammation of the liver. It is most commonly caused by a viral infection, however, there are other causes as well.

Hepatitis has been classified depending on the virus responsible for the infection. These include hepatitis A, B, C, D, and E.

Here we will discuss Hepatitis A, the most relevant type for international travelers.

The risk of contracting hepatitis A in the United States is very low.

Although recently there have been a few pockets where outbreaks have occurred, it is still rare and more of a risk factor for those who travel abroad where hepatitis A is prevalent.

With millions of people traveling abroad every year the chance of exposure to disease causing pathogens is very real.

Travel increases the chance of exposure to diseases that may or may not be present at your home country and puts you at increased risk of acquiring an infection.

One of the more common ailments that poses a risk to travelers is Hepatitis A (HAV) infection.

Hepatitis A virus (HAV) infection is prevalent in many developing countries and is among the most common preventable infections acquired by travelers.

Humans are the only known reservoir for HAV. That means this viral illness could potentially be eradicated with successful employment of widespread prevention strategies.

In fact, since the hepatitis A vaccine became available in the US in 1995, the incidence of HAV infection has gone down by about 95 percent.

What is HAV

Hepatitis A is a communicable disease of the liver caused by a virus. Transmission is from person-to-person through the fecal-oral route, contact with an infected person or consumption of contaminated food or water.

Treatment

HAV infection is usually self-limited, and treatment consists of supportive care.

Medications that might cause liver damage or are metabolized by the liver (such as Tylenol or alcohol) should be used with caution once an infection is confirmed.

Most will have a full recovery by about three months. The vast majority of those infected will have a complete recovery by six months.

Prevention

HAV can be prevented by vaccination prior to travel.

This is a vaccine preventable disease!

The Advisory Committee on Immunization Practices of the United States Centers for Disease Control and Prevention (CDC) recommends vaccination prior to potential hepatitis A exposure for the following individuals:

1. All children at age one year (ie, 12 to 23 months); children who have not been vaccinated by age two can be vaccinated at subsequent visits.

2. Children between ages 2 and 18 years who live in regions where routine hepatitis A vaccination has been implemented because of high disease incidence.

3. Those traveling to or working in countries with high or intermediate rates of HAV. Some advise that travelers outside the United States consider hepatitis A vaccination regardless of their destination.

4. For infants age 6 to 11 months who are traveling internationally, vaccination should be administered.

5. Men who have sex with men.

6. Illicit drug users

7. Those working with HAV infected primates or with HAV in a research laboratory.

8. Travelers with chronic liver disease. Patients with chronic hepatitis B and C virus are at risk for HAV superinfection and fulminant hepatic failure.

9. Individuals with clotting factor disorders.

10. Individuals with direct contact to others who have hepatitis A.

11. Homeless individuals aged ≥1 year.

12. Anyone wishing to obtain immunity.

I would add that if you are an adventurous eater and like to sample foods from street vendors, you may want to consider getting this vaccine.

The primary tool for protection against hepatitis A prior to travel is vaccination. This is the best way to get high enough antibody concentrations to have a durable immune response.

Ideally the vaccination should be completed two weeks prior to travel but really anytime prior to travel is better than leaving unvaccinated.

Available vaccines

Two single-antigen inactivated hepatitis A vaccines are licensed in the United States.

These are HAVRIX and VAQTA. A combination inactivated vaccine, TWINRIX, is also licensed in the United States; it contains both hepatitis A (HAVRIX) and hepatitis B (Engerix-B).

Combination HAV and typhoid vaccines (Hepatyrix and Vivaxim) are available in some areas outside the United States.

There is a live attenuated hepatitis A vaccine but it is not available in the United States.

Hepatitis A vaccine

As mentioned above, Hepatitis A is a vaccine preventable infection.

Depending on which vaccine you get, you will need two to three doses.

The single antigen inactivated vaccine (HAVRIX or VAQTA) consists of two doses for adults.

Immunization with the combination inactivated vaccine, TWINRIX, consists of three doses for adults.

The most common adverse events are fever, discomfort at the injection site, rash, and headache.

Serious adverse events (including Guillain-Barré syndrome, elevated liver tests, and immune thrombocytopenia) are exceedingly rare and without any definite link to the vaccine itself.

Hygiene

Other than getting vaccinated, there are other steps you can take to prevent HAV infection including:

1. Hand washing - this is self explanatory and just a good practice to get into.

2. Avoiding tap water and raw foods in areas with poor sanitation.

3. Heating foods appropriately (the virus can be inactivated by heating to >185°F (>85°C) for one minute). Cooked foods can transmit HAV if the temperature during food preparation is inadequate to kill the virus or if food is contaminated after cooking.

4. Chlorine, iodine, and disinfecting solutions are effective for inactivation of HAV.

Conclusion

Hepatitis A virus infection is prevalent in many developing countries and is among the most common preventable infections acquired by travelers.

Prevention of HAV infection includes vaccination and attention to hygienic practices.

Safe travels.

Please remember that medical information provided by us must be considered an educational service only. This blog should not be relied upon as medical judgement and does not replace your physician’s independent judgement. This is NOT medical advice. Please seek the advice of your physician.