The Hepatitis B vaccine series requires 3 shots and Hepatitis A vaccine requires 2 shots. The last dose in both vaccines takes place 6 months after the first dose, so some people don't get the last dose until after their travels. If you've only received a portion of the total doses required for the full series, do you get any protection? If so, to what degree?

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    This question appears to be off-topic because it is about medicine – Dirty-flow Jul 31 '13 at 20:02
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    These vaccines are recommended for travel to many countries. Lots of people only get them before travel but do not complete the series because they take 6 months. – imagineerThis Jul 31 '13 at 20:54
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    but how many shots do you need is not a travel question any more! – Dirty-flow Jul 31 '13 at 21:54
  • I beg to differ. If you knew you didn't get any protection from one dose of a vaccine in a series, could that potentially affect your decision to travel in a country that the vaccine is recommended for? – imagineerThis Jul 31 '13 at 23:36
  • that is like asking how often should you replace the timing belt of your car. You need the car to travel and if there is a risk to damage the engine, this may change your decision to travel but... how often to change your timing belt is NOT A TRAVEL QUESTION! – Dirty-flow Aug 1 '13 at 7:46

You could hardly be better.

According to Canadian public health agency, 95-100% of patients produce antibodies after 1 shot of Hepatitis A, nearly 100% after two shots.

Though, this does not mean you are nearly 100% immune after two shots


In serologic studies of HA vaccines, 95% to 100% of vaccinees developed protective concentrations of antibody against HA after a single dose of HA vaccine, and nearly 100% seroconverted after receiving two doses.

There is no reduction, and possibly even an increase, in seroprotection rates achieved by HAHB vaccine compared with monovalent HA and HB vaccines. Equivalent seroconversion rates are achieved by HA-Typh-I vaccine compared with typhoid and monovalent HA vaccines.

Source: http://www.phac-aspc.gc.ca/publicat/cig-gci/p04-hepa-eng.php#a3

Disclaimer: This is no medical advice and you should consult an authorized practitioner.

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