Friday, October 16, 2015

Hepatitis A: Are you protected?


Please see the updated recommendation February 2019
Parents have you gotten your Hepatitis A vaccine?

Hepatitis A is an inflammatory disease of the liver that is caused by a virus. Some people consider the Hep A shot a travel vaccine because it  is the most common vaccine-preventable illness that folks get infected with when traveling. We think that everyone over a year old should get it even if you aren't going anywhere. Hepatitis A is certainly more common in countries with lower standards of sanitation, but this virus doesn’t care about borders. There are plenty of cases right here in this country.

Transmission occurs  through direct person-to-person contact (fecal-oral transmission); contaminated water, ice, or shellfish harvested from sewage-contaminated water. You can also get it from contaminated raw, inadequately cooked, frozen fruits, vegetables, or other foods. Hepatitis A is quite hardy and can live outside the body for quite a while. It can  survive being frozen. This is a nasty virus. Hand washing is important and can stop you from spreading it, but won't protect you from catching it. It makes no sense not to get the vaccine if eligible.

Poor hand washing and then handling food is a common mode of transmission, but so is changing a diaper. Thus diaper age children, infected with the virus, are a large reservoir for spreading it. People are most infectious 1–2 weeks before the onset of clinical signs and symptoms, and can shed the virus in the stool for months and months. Dr. Schwanke had read somewhere that in some cases poop can remain contagious for up to a year!

The incubation period averages 28 days (range 15–50 days). Infection can be asymptomatic or range in severity from a mild illness lasting 1–2 weeks to a severely disabling disease lasting several months. Most common symptoms include the abrupt onset of fever, malaise, poor appetite, nausea, and abdominal discomfort, followed within a few days by jaundice. Urine may be very dark colored and stool is often clay colored or freakishly light. The likelihood of having symptoms with a Hep-A infection is related to the age of the infected person. Fortunately, although it is rarely fatal, adults with this can become quite SICK!

Here is one of the most important facts worth emphasizing: In children aged <6 years, most (70%) infections are asymptomatic. In the young children who are actually acting ill, jaundice is not a common symptom, so it might be awhile until someone figures out that they are dealing with a form of Hepatitis. Most of the time,young children don’t usually exhibit many symptoms at all, or appear too ill, but they pass the virus along to their caregivers who get walloped. We have seen it sweep through a daycare, with many of the caregivers and parents catching it.

The vaccine first became available in Europe back in 1993 and started getting phased in to our vaccine schedule in 1996. Interestingly, although it is recommended, it is not one of the vaccines that are required for school entry. It can be given as soon as a child reaches their first birthday and should be followed by a booster six to twelve months later. Protection against hepatitis A begins approximately two to four weeks after the initial vaccination. Protection is proven to last at least 15 years and is estimated to last at least 25 years if the full course is administered. There is currently no follow up booster suggested, but if the immunity looks like it is waning, I imagine that will get revisited. The vaccine comes only in preservative free form (no thimerosal concerns). I rarely see any side effects at all. Once in awhile a baby post vaccine might be extra fussy, but that is rare and not necessarily shot related.

This one requires little thought. You should make sure that Hepatitis A vaccine is included in your child’s immunization schedule. Our office routinely starts the series within the first 15 months. Parents, also please check your own health records and make sure that you are protected. Adults are often quite clueless about their own vaccination status!