Nepedia
Back to Discover
Advanced Reader
🧬

Hepatitis E

life science Maturity 11-13 Next article →

Hepatitis E is a viral infection that causes inflammation of the liver. It is caused by the hepatitis E virus, or HEV. This virus is one of five known human hepatitis viruses. The others are types A, B, C, and D. HEV is a positive-sense, single-stranded, nonenveloped, RNA icosahedral virus. This means it has a specific geometric shape and a type of genetic material called RNA. While many people recover from this illness, it can be very dangerous for specific groups of people.

Hepatitis E Virus in Pork Liver Sausage
Hepatitis E Virus in Pork Liver Sausage

Transmission of the virus happens through different routes depending on the genotype. Genotypes 1 and 2 mostly use a fecal-oral route. This means the virus spreads when contaminated food or water enters a person's mouth. This often happens after heavy rainfall or monsoons. Flooding can wash sewage into the water supplies used by communities. In contrast, genotypes 3 and 4 are zoonotic. This means they spread from animals to humans. People can catch these types by eating undercooked meat or having direct contact with animals like pigs or deer.

Geldanamycin
Geldanamycin

The virus goes through several stages during an infection. The incubation period, or the time between catching the virus and feeling sick, averages 40 days. This period can range from 2 to 8 weeks. During this time, viral RNA can be detected in a person's stool and blood serum. As the illness begins, a person might experience a prodromal phase. Symptoms during the symptomatic phase include fatigue, nausea, and jaundice, which is yellowing of the skin. Doctors can see elevated hepatic aminotransferase levels in the blood during this time. As the body recovers, IgM antibodies disappear and IgG antibodies increase.

LocationNamibia
LocationNamibia

HEV can present in different clinical forms. Most cases are acute, meaning the illness is temporary and the person recovers. However, some people develop chronic hepatitis E. This is a persistent infection that lasts for at least three months of continuous viremia. This is most common in people with weakened immune systems, such as organ transplant recipients. Another severe form is fulminant liver failure. This is a rapid and life-threatening condition where the liver stops working. This is particularly dangerous for pregnant women, especially during their third trimester. In these cases, death rates can reach 20% to 25%.

Hepatitis E Virus in Pork Liver Sausage
Hepatitis E Virus in Pork Liver Sausage

Scientists have a long history of studying this virus. The virus was discovered in 1983 by researchers studying Soviet soldiers in Afghanistan. A Russian virologist named Mikhail S. Balayan identified the virus. He did this after ingesting fecal samples from nine soldiers that were mixed with kefir. Even before the virus was identified, large outbreaks were recorded. In 1955, an epidemic in New Delhi affected tens of thousands of people. Scientists later identified the virus as the cause by testing stored samples from that time.

Hepatitis E Virus in Pork Liver Sausage
Hepatitis E Virus in Pork Liver Sausage

The virus is classified into different groups based on its genetics. It belongs to the family Hepeviridae. This family includes two genera: Orthohepevirus, which affects mammals and birds, and Piscihepevirus, which affects cutthroat trout. There are eight known genotypes of the human virus. Genotype 1 has five subtypes, and genotype 2 has two subtypes. Genotypes 3 and 4 are more complex, with 10 and seven subtypes respectively. In 2017, it was estimated that more than 19 million people were affected by hepatitis E.

Hepatitis E Virus in Pork Liver Sausage
Hepatitis E Virus in Pork Liver Sausage

HEV is a significant global health concern with many connections to animal health and sanitation. In the United Kingdom, studies showed that 10% of pork sausages contained the virus. This highlights the importance of cooking meat to the correct temperature. Some research suggests food must reach a specific temperature for 20 minutes to kill the virus. Beyond the liver, the virus can affect other systems. It has been linked to neurological complications like Guillain-Barré syndrome and acute pancreatitis. Understanding these connections helps doctors manage the complex ways the virus affects the human body.

638 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (3)
File:Hepatitis E Virus in Pork Liver Sausage.jpg
Hepatitis E Virus in Pork Liver Sausage.jpg
File:Geldanamycin.svg
Geldanamycin.svg
File:LocationNamibia.svg
LocationNamibia.svg
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.