Fewer than half of teenagers in parts of England have been vaccinated against polio, official data suggests as health chiefs sound the alarm over a suspected outbreak of the disease that has been eradicated in Britain for 20 years.
Parents of unvaccinated children are to be contacted by the NHS as part of a targeted vaccine drive in London — where polio is thought to be spreading — amid fears the disease could take off for the first time in decades.
Children are routinely immunised…
