What Is the Difference Between IPV and OPV for Immigration?
Quick Answer
IPV (inactivated polio vaccine) is the only polio vaccine used in the United States and is required for immigration. OPV (oral polio vaccine) is a live vaccine used in many other countries. Foreign OPV records are generally accepted, but additional IPV doses may be required depending on your vaccination history.
Two Types of Polio Vaccine
There are two types of polio vaccine: inactivated polio vaccine (IPV), which is given as an injection, and oral polio vaccine (OPV), which is given as drops by mouth. The United States switched exclusively to IPV in 2000 due to the rare risk of vaccine-associated paralytic polio (VAPP) associated with OPV. Many other countries continue to use OPV as part of their national immunization programs.
IPV Is Required in the United States
For immigration purposes, USCIS requires polio vaccination in accordance with ACIP recommendations, which specify IPV. The standard IPV series consists of 4 doses: at 2 months, 4 months, 6–18 months, and 4–6 years of age. Adults who were never vaccinated against polio need 3 doses of IPV. Adults who received a complete polio series as children generally do not need a booster unless they are at increased risk.
How Foreign OPV Records Are Handled
If you received OPV in another country, your vaccination records will generally be accepted and credited toward the polio requirement. The civil surgeon will assess your OPV vaccination history and determine whether additional IPV doses are needed. In many cases, individuals who received a complete OPV series are considered adequately protected against polio, and no additional IPV doses are required. However, this depends on the number of OPV doses received and your age.
Catch-Up IPV for Adults
Adults who have never been vaccinated against polio need 3 doses of IPV: dose 1 at any time, dose 2 at least 4 weeks after dose 1, and dose 3 at least 6 months after dose 2. Adults who received only 1 or 2 doses of polio vaccine (IPV or OPV) should complete the series. Adults who received a complete series of IPV or OPV do not need additional doses unless they are traveling to a polio-endemic area or are at increased risk.
Polio Vaccine Safety
IPV is an inactivated vaccine and is safe for all individuals, including pregnant women and immunocompromised patients. It cannot cause polio. OPV, being a live vaccine, is no longer used in the United States due to the rare risk of VAPP. If you received OPV in the past, you do not need to be concerned — OPV provides excellent protection against polio.
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