Who produces hepatitis A virus?

From the Guidelines

Hepatitis A virus is produced by infected human liver cells, specifically hepatocytes, where the virus replicates and is then shed in feces, allowing for transmission to other individuals. The virus enters the bloodstream and travels to the liver, invading hepatocytes and using the cell's machinery to produce new viral particles 1. These newly formed viruses are then released from the infected liver cells and can be shed in feces, allowing for transmission to other individuals. Unlike hepatitis B or C, hepatitis A does not cause chronic infection and is typically cleared by the immune system within a few weeks to months. The virus is primarily transmitted through the fecal-oral route, often via contaminated food or water, or through close personal contact with an infected individual.

Some key points to consider about hepatitis A transmission include:

• The virus can be shed in high concentrations in feces from 2–3 weeks before to 1 week after the onset of clinical illness 1
• Transmission of HAV during sexual activity probably results from fecal-oral contact 1
• Bloodborne transmission of HAV is uncommon, although viremia occurs early during infection and can persist for weeks after symptom onset 1
• Prevention is possible through vaccination and good hygiene practices, particularly handwashing after using the bathroom and before handling food.

It's worth noting that the risk for symptomatic infection is directly related to age, with approximately 70% of adults having symptoms compatible with acute viral hepatitis and the majority of children having either asymptomatic or unrecognized infection 1. Antibody produced in response to HAV infection persists for life and confers protection against reinfection 1.

From the FDA Drug Label

The virus (strain HM175) is propagated in MRC-5 human diploid cells.

The hepatitis A virus is produced in MRC-5 human diploid cells 2.

• The virus is propagated in these cells.
• The cells are then lysed to form a suspension.
• This suspension is purified and used to create the hepatitis A vaccine.

From the Research

Hepatitis A Virus Production

The hepatitis A virus (HAV) is produced by an infected person, typically through the fecal-oral route of transmission. Key points to consider:

• The virus is shed in the stool of infected individuals, and can be transmitted through close contact with an infected person or by ingestion of contaminated food or water 3, 4.
• Food handlers with hepatitis A can frequently be identified as the source of outbreaks, highlighting the importance of proper hygiene and sanitation practices 3.
• The virus can also be transmitted through other routes, such as drug use or homelessness, as well as through sexual contact among men who have sex with men (MSM) 4.

Transmission and Risk Factors

Transmission of HAV can occur through various means, including:

• Direct contact with an infected person
• Ingestion of contaminated food or water
• Close contact with an infected person, such as through sexual contact or sharing of personal items
• Poor sanitation and hygiene practices
• Certain high-risk behaviors, such as drug use or homelessness 4, 5.

Vaccine Prevention

The hepatitis A vaccine is an effective means of preventing infection, and is recommended for:

• Children 12 to 23 months of age
• Individuals at high risk of contracting the infection, such as those who use illegal drugs, travel to areas endemic for hepatitis A, or are incarcerated
• Persons at high risk of complications from hepatitis A, such as those with chronic liver disease or HIV infection 5, 6.