Which virus is mainly spread through sharing needles by intravenous drug users?

Which virus is mainly spread through sharing needles by intravenous drug users?

• A. Human immunodeficiency virus
• B. Hepatitis B virus
• C. Hepatitis C virus
• D. Influenza virus

Answer: (A)

Sharing needles introduces infected blood directly into another person’s bloodstream, so the virus most efficiently transmitted this way is the one with the highest blood‑to‑blood transmission risk and high prevalence in IV drug–using networks. Hepatitis C virus fits that description best here: it is highly efficiently transmitted through percutaneous exposure and is very common among people who share needles. Vaccination against Hepatitis B reduces its risk, and while HIV can also be spread by needle sharing, its per‑exposure transmission rate is lower than that of Hepatitis C. Influenza spreads mainly through respiratory droplets, not blood exposure. So, Hepatitis C virus is the virus most characteristically spread by sharing needles among intravenous drug users.

Sharing needles introduces infected blood directly into another person’s bloodstream, so the virus most efficiently transmitted this way is the one with the highest blood‑to‑blood transmission risk and high prevalence in IV drug–using networks. Hepatitis C virus fits that description best here: it is highly efficiently transmitted through percutaneous exposure and is very common among people who share needles. Vaccination against Hepatitis B reduces its risk, and while HIV can also be spread by needle sharing, its per‑exposure transmission rate is lower than that of Hepatitis C. Influenza spreads mainly through respiratory droplets, not blood exposure. So, Hepatitis C virus is the virus most characteristically spread by sharing needles among intravenous drug users.