Teton Wilderness, Wyoming. Part of one of the largest contiguous wild areas in the United States, Teton Wilderness bridges the area between Grand Teton National Park and the especially remote southeast corner of Yellowstone, and is bordered by two other federal wilderness areas within Bridger-Teton National Forest.
Four doses of polio vaccine (IPV) are routinely recommended for U.S. children at ages 2 months, 4 months, 6-18 months, and 4-6 years. The first dose may be given as early as age 6 weeks.
OPV is usually provided in vials containing 10â20 doses of vaccine. A single dose of oral polio vaccine (usually two drops) contains 1,000,000 infectious units of Sabin 1 (effective against PV1), 100,000 infectious units of the Sabin 2 strain, and 600,000 infectious units of Sabin 3.