Viral hepatitis is transmitted by food or water contaminated by fecal material. It is a serious inflammatory disease of the liver that is associated with poor sanitation and is common in developing countries. Two different viruses are commonly associated with fecal-borne hepatitis: hepatitis A virus (HAV) and hepatitis E virus (HEV).

HAV infections have an incubation period of 14–45 days, with an average of 28 days. During this time, some patients who smoke may develop distaste for cigarettes. Most children with HAV infections are asymptomatic, whereas only a small number of adults are asymptomatic. Most symptomatic patients with HAV infection have jaundice.

The initial symptoms of HAV include fever (about 39°C), malaise, fatigue, headache, anorexia, nausea and vomiting, pain in the right upper quadrant, and hepatosplenomegaly. Classic symptoms of hepatitis may develop later; symptoms include cholestasis (dark urine and clay-colored stools) followed within 1–5 days by clinical jaundice (yellowing of skin and whites of eyes). The liver is enlarged and tender. Liver damage causes increased blood levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and bilirubin. Groups or settings where people are at higher risk of acquiring an HAV infection are listed in Table HEP-1.

Pathogenesis

After ingestion, HAV and HEV can withstand the harsh conditions in the stomach and intestines. These viruses replicate in the oropharynx and epithelial lining of the intestines, where they initiate a transient viremia and infect the liver. HAV and HEV bind to and replicate primarily within liver parenchymal cells. The viruses are released into bile and eventually into stool. HAV and HEV may be shed in feces for 10 days before clinical symptoms appear.

Taking a Closer Look

HEPATITIS E:  hepatitis E is a virus that infects your liver. It can cause your liver to swell up.

Most people with hepatitis E get better within a few months. Usually it doesn’t lead to long-term illness or liver damage like some other forms of hepatitis do. But hepatitis E can be dangerous for pregnant women or anyone with weak immune systems, including the elderly or people who are ill.

Causes

The hepatitis E virus spreads through poop. You can catch it if you drink or eat something that has been in contact with the stool of someone who has the virus. Hepatitis E is more common in parts of the world with poor hand washing habits and lack of clean water. It happens less often in the U.S., where water and sewage plants kill the virus before it gets into the drinking supply.

You also can get hepatitis E if you eat undercooked meat from infected animals, such as pigs or deer. Less often, you can get the virus from raw shellfish that comes from tainted water.

Symptoms

You might not have any. If you do have symptoms, they may start anywhere from 2 to 6 weeks after your infection. They may include:

• Mild fever
• Feeling very tired
• Less hunger
• Feeling sick to your stomach
• Throwing up
• Belly pain
• Dark pee
• Light-colored poop
• Skin rash or Itching
• Joint Pain
• Yellowish Skin or eyes

HEPATITIS A: Hepatitis A is a liver disease caused by the hepatitis A virus (HAV). The virus is primarily spread when an uninfected (and unvaccinated) person ingests food or water that is contaminated with the faeces of an infected person. The disease is closely associated with unsafe water or food, inadequate sanitation, poor personal hygiene and oral-anal sex.

Unlike hepatitis B and C, hepatitis A does not cause chronic liver disease and is rarely fatal, but it can cause debilitating symptoms and fulminant hepatitis (acute liver failure), which is often fatal. Overall, WHO estimated that in 2016, 7 134 persons died from hepatitis A worldwide (accounting for 0.5% of the mortality due to viral hepatitis).

Hepatitis A occurs sporadically and in epidemics worldwide, with a tendency for cyclic recurrences. The hepatitis A virus is one of the most frequent causes of foodborne infection. Epidemics related to contaminated food or water can erupt explosively, such as the epidemic in Shanghai in 1988 that affected about 300 000 people¹. They can be also prolonged, affecting communities for months through person-to-person transmission. Hepatitis A viruses persist in the environment and can withstand food-production processes routinely used to inactivate and/or control bacterial pathogens.

The disease can lead to significant economic and social consequences in communities. It can take weeks or months for people recovering from the illness to return to work, school, or daily life. The impact on food establishments identified with the virus, and local productivity in general, can be substantial.

Symptoms

The incubation period of hepatitis A is usually 14–28 days.

Symptoms of hepatitis A range from mild to severe, and can include fever, malaise, loss of appetite, diarrhea, nausea, abdominal discomfort, dark-coloured urine and jaundice (a yellowing of the skin and whites of the eyes). Not everyone who is infected will have all of the symptoms.

Adults have signs and symptoms of illness more often than children. The severity of disease and fatal outcomes are higher in older age groups. Infected children under 6 years of age do not usually experience noticeable symptoms, and only 10% develop jaundice. Among older children and adults, infection usually causes more severe symptoms, with jaundice occurring in more than 70% of cases. Hepatitis A sometimes relapses. The person who just recovered falls sick again with another acute episode. This is, however, followed by recovery.

Who is at risk?

Anyone who has not been vaccinated or previously infected can get infected with hepatitis A virus. In areas where the virus is widespread (high endemicity), most hepatitis A infections occur during early childhood. Risk factors include:

• poor sanitation;
• lack of safe water;
• living in a household with an infected person;
• being a sexual partner of someone with acute hepatitis A infection;
• use of recreational drugs;
• sex between men;
• Travelling to areas of high endemicity without being immunized.