What are the advantages of the Oral Polio Vaccine (OPV)?

• A. It is orally applicable, inexpensive, and can be administered by volunteers without sterile equipment.
• B. It yields lifelong immunity after a single dose.
• C. It never requires cold chain.
• D. It is only effective in adults.

Answer: (A)

Oral administration, low cost, and field-friendly deployment are the big advantages of the Oral Polio Vaccine. Because it is given by mouth, it eliminates needles and syringes, so it can be provided by volunteers or lay health workers after minimal training, which makes mass campaigns much easier to organize. Its low cost per dose and simple logistics allow vaccination programs to reach hard‑to‑access or resource‑limited areas without the need for extensive medical infrastructure. In addition, OPV tends to induce mucosal immunity in the gut, helping to reduce person-to-person transmission, and the live vaccine virus can spread to contacts, providing indirect protection to others. All of these factors together—easy, inexpensive, and scalable delivery—make OPV especially useful in eradication efforts and large immunization drives.

It’s helpful to note why other statements aren’t as accurate: a single dose does not usually confer lifelong immunity—boosters are often needed; cold chain and proper storage remain important to preserve the vaccine’s potency; and OPV is widely used in children, not only in adults.