The Centers for Disease Control and Prevention has recommended that children should get two shots of chicken pox vaccine instead of one because new research shows that the vaccine stops its effects over time. Many children who were given shots as a chicken pox vaccine in their young age are still seen to get infected by the chicken pox disease suggesting the vaccine can wear off with time.

However, this highly contagious disease has nearly became rarer with the advent of a new vaccine in 1995. According to a new study, only around 11,300 cases of chicken pox were detected over 10 years. Nearly 90 percent of the people who were victim to the disease had not been vaccinated.

Since the disease is more advent in children as they grow up, there are chances that the child who got the vaccine many years ago were more likely to become ill than those who had been vaccinated recently. Experts believe that doubling the vaccine reduces the odds that the effects will wear off.

Chicken pox is the common name for Varicella zoster, classically one of the childhood infectious diseases caught and survived by most children. It starts with conjunctival and catarrhal symptoms, moderate fever and then characteristic spots appearing in two or three waves, mainly on the body and head rather than the hands and becoming itchy raw pox (pocks), small open sores which heal mostly without scarring.

Chickenpox has a 10-14 day incubation period and is highly contagious by air transmission two days before symptoms appear. Following primary infection there is usually lifelong protective immunity from further episodes of chickenpox. Recurrent chickenpox is fairly rare but more likely in people with compromised immune systems.