Microbiology
Summary
Hepatitis A virus (HAV) is a naked, positive-sense RNA virus in the Picornaviridae family. A notable feature of HAV is its acid-stable nature, allowing it to withstand stomach acidity and facilitating fecal-oral transmission through contaminated food, water, or close contact, including sexual contact. Individuals who inject drugs are also at a higher risk of contracting the virus.
While many developed countries have effective water purification systems, HAV can still be acquired from uncooked shellfish sourced from contaminated water or private wells used for drinking. This risk extends to travelers visiting endemic areas, particularly in the Southern hemisphere.
Symptoms of hepatitis A often go unnoticed, but can present as acute viral hepatitis, accompanied by fever, hepatomegaly, and jaundice, especially in adults. The disease is typically self-limiting, lasting less than two months with no chronic state. Interestingly, infected smokers may develop an aversion to tobacco.
For prevention, an inactivated vaccine is available, recommended for high-risk individuals such as those in endemic areas, individuals with chronic liver disease, people experiencing homelessness, men who have sex with men, and those who inject drugs.
Lesson Outline
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FAQs
The hepatitis A virus (HAV) is a virus that causes hepatitis A, an infectious disease primarily affecting the liver. HAV is a member of Picornaviridae, a family of positive-sense RNA viruses.
Symptoms of hepatitis A may include fever, fatigue, loss of appetite, nausea, vomiting, abdominal pain, dark urine, clay-colored stools, joint pain, and jaundice (a yellowing of the skin or eyes).
Hepatitis A is usually transmitted by the fecal-oral route, either through person-to-person contact or consumption of contaminated food or water. It can also be transmitted through certain sexual practices and recreational drug use.
The most effective method for preventing hepatitis A is through vaccination. Good personal hygiene and proper handwashing can also help stop the spread of the virus. Additionally, avoid eating undercooked or raw shellfish and unpasteurized foods when traveling to areas with higher rates of hepatitis A.
Currently, there is no specific antiviral therapy for hepatitis A. Treatment is mostly supportive, focusing on maintaining comfort and adequate nutritional balance, including replacement of fluids lost from vomiting and diarrhea. In more severe cases hospitalization may be necessary. The hepatitis A vaccine can prevent the infection, but it must be administered before or within two weeks of exposure to be effective.
