How much blood would it take to contract hep b? like one drop if it mixes?

Hepatitis B. Transmission via needlestick or exposure to body fluids (blood or semen) can occur with small volumes of exposure. If you have been exposed, you should be tested for immunity and if not immune followed for seroconversion. If possible, the person from whom the exposure occurred should be tested. Thanks for trusting HealthTap!