Which is not transmitted through blood-
**Core Concept**
Hepatitis viruses are primarily transmitted through blood, but there are exceptions. The primary mode of transmission for some viruses is through other routes, such as fecal-oral, respiratory, or vector-borne transmission.
**Why the Correct Answer is Right**
Hepatitis A virus (HAV) is primarily transmitted through the fecal-oral route, where the virus is ingested through contaminated food or water. This mode of transmission is distinct from the blood-borne transmission seen with hepatitis B (HBV) and C (HCV) viruses. The hepatitis A virus is highly contagious and can be spread through direct contact with an infected person or through contaminated surfaces.
**Why Each Wrong Option is Incorrect**
**Option A:** Hepatitis B virus (HBV) is indeed transmitted through blood, where the virus can be found in the serum of infected individuals. HBV can cause acute and chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma.
**Option B:** Hepatitis C virus (HCV) is primarily transmitted through blood, where the virus can be found in the serum of infected individuals. HCV can cause acute and chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma.
**Option C:** Hepatitis E virus (HEV) can be transmitted through both blood and fecal-oral routes. However, the primary mode of transmission for HEV is through the fecal-oral route.
**Clinical Pearl / High-Yield Fact**
Hepatitis A is a vaccine-preventable disease, and vaccination is recommended for individuals traveling to high-risk areas, healthcare workers, and individuals with chronic liver disease.
**Correct Answer: A. Hepatitis A virus (HAV)**