|More On Hepatitis Viruses- New Kid on the Block
We have all heard of various hepatitis viruses: A, B, C (formerly known as non-A non-B; see earlier blog entry) hepatitis. Hepatitis A is often spread through fecal-oral contamination of foods and water and other items. Both Hepatitis B and C viruses are transmitted by the blood borne route. Vaccines for Hepatitis A and B are available and are extremely effective and safe. I have written previously about hepatitis C. I would now like to introduce a “new” virus to add to our vocabulary.
Hepatitis E virus was first described in 1955 in New Delhi, India. It presents with a similar mode of transmission as Hepatitis A, with fecally contaminated water the most common vehicle. Unlike Hepatitis A Virus, however, blood borne transmission of Hepatitis E Virus has been described. The reason to bring this up today is that Hepatitis E virus has now been found for the first time in farmed rabbits living in the US. This virus was found in rabbits in China in 2009, in pigs in 1997 and in many other animals species, thereafter, including, deer, wild boar, and rats, Interestingly, Hepatitis E Virus in both pigs and rabbits can be transmitted to people.
Hepatitis E infection in pregnant woman is a very serious illness and fatal infections in pregnant women are not uncommon. Otherwise it is similar to hepatitis A, in that there is no chronic carrier infection established after the acute infection resolves. The acute infection can be more severe though than that seen in Hepatitis A Virus infection. In the US, patients with Hepatitis E have usually been out of the country, visiting or living in endemic regions (Asia, Africa, the Middle East, and Central America). When traveling to these areas, it is particularly important to do as much as you can to avoid exposure to this and other viruses and pathogenic bacteria, such as avoiding drinking water of unknown purity, and uncooked fruits or vegetables or shell fish.
In case you were wondering, there is a hepatitis D virus. It actually is called hepatitis delta virus and it is a defective virus in that it can only grow in the presence of active infection with the hepatitis B virus. If Hepatitis B Virus is not present, neither is the delta virus.
Posted by DrSugar on 11/29/2011 at 11:01 AM