Print Email. A sinkhole, also known as a sink-hole, sink, swallow hole, shakehole, swallet or doline, is a natural depression or hole in the Earth's surface which may have various causes. Some are caused by karst processesâfor example, the chemical dissolution of carbonate rocks or suffosion processes in sandstone.
MMR vaccine is recommended routinely for all children at age 12 through 15 months, with a second dose at age 4 through 6 years. The second dose of MMR can be given as early as 4 weeks (28 days) after the first dose and be counted as a valid dose if both doses were given after the child's first birthday.easles vaccine, given as MMR, may be effective if given within the first 3 days (72 hours) after exposure to measles. Immune globulin may be effective for as long as 6 days after exposure.
The academy recommends the first varicella dose be administered at age 12 to 15 months. However, Dr. Chaves and colleagues noted, No long-term data are available on the duration of immunity afforded by the second dose of vaccine..