‘We saw significant declines in prices of varicella following the one-dosage vaccine was recommended in 1995 in the U.S., and we’re continuing to discover extra declines in varicella after two dosages were recommended in 2006,’ she added. The largest reduction in chickenpox occurred among children and teens aged 1 to 19, a group targeted for vaccination against the condition. But there have been also significant drops in outpatient visits and hospitalizations among children younger than 12 weeks – – for whom the vaccine isn’t suggested – – and among adults, who tend not to get vaccinated. The possibility is suggested by These findings of something called herd immunity. ‘The surrounding population which can be vaccinated are not getting sick, and therefore the data claim that these infants are also being protected,’ Leung said.