A Single Dose of Chicken Pox Vaccine is Not Always Effective

Is your child completely safe from chicken pox once he/she has received a single dose of the chicken pox vaccine? Unfortunately, the answer is ‘No.’ Some children still get infected despite taking the vaccine, though the illness usually tends to be milder.  An article in the US Pharmacist highlighted some important facts about chicken pox, its treatment and prevention. Chicken pox usually affects children though it may also affect adults.  It spreads through secretions of the respiratory tract or through direct contact with the skin lesions of infected people.  Symptoms of chicken pox include low fever, headache and malaise.  A rash with small eruptions filled with fluid called vesicles develops on the whole body, especially the face, scalp, trunk and limbs.  

Healthy children with chicken pox usually recover on their own with minimal treatment to relieve their symptoms.  Itching is a main problem that makes the patient uncomfortable.  It may be treated with calamine lotion, lotions containing camphor and menthol, oatmeal baths, cool or wet compresses, and tepid baths.  Oral antihistamines also help to relieve the itching.  Fever may be treated with acetaminophen and not salicylates.  Fingernails should be cut short to avoid scratches and bursting of lesions.

Though an antiviral medication acyclovir is available for the treatment of chicken pox, its routine use in healthy children is not recommended.  It may, however, be considered in healthy individuals at a risk for moderate-to-severe disease or complications like individuals older than 12 years, some pregnant women, persons with skin or lung diseases, persons receiving steroids or children receiving salicylates over prolonged periods.  


Chicken pox usually does not cause complications.  In very rare cases, complications may be observed like bacterial infection, brain involvement, or pneumonia in adults.  Reye’s syndrome, a condition affecting the kidneys, may develop if the patient also receives aspirin for the fever.  The virus that remains dormant through childhood can get re-activated in the nerves during adulthood resulting in shingles.

Two vaccines are available for chicken pox in the United States, Varivax and ProQuad.   ProQuad is a combination vaccine that is effective against four diseases, measles, mumps, German measles and chicken pox.  In addition, one vaccine is available against shingles.

Though the vaccine against chicken pox has been found to be effective in reducing the number of cases, yet the vaccine has not proved to be 100% effective, with cases occurring in patients who have received the vaccine in the past.  Fortunately, most of the cases are mild and do not develop complications.

Advertisement

Side effects of the vaccine include rash, fever and local reactions like pain, soreness, redness and swelling at the injection site. Some serious reactions affecting the nervous system have also been reported like 12 cases of encephalitis, 5 cases of meningitis, and 5 cases of cerebellar ataxia (a condition where a part of the brain called the cerebellum is affected).

The Center for Disease Control, Atlanta now recommends two doses of chicken pox vaccine to increase the effectiveness of the vaccine.  The first dose should be administered between 12 to 15 months of age and the second dose between 4 and 6 years.  Individuals who have missed the second dose may be given a catch-up dose later, especially during epidemics.

Advertisement

The Indian Academy of Pediatrics currently recommends only one dose of chicken pox vaccine in children.  This is keeping in mind the high cost of the vaccine and that the vaccine has not yet been included in the National Immunization Schedule.  However, recommendations could change in the future depending on the performance of the vaccine.

Reference:

1. Itching Like Crazy: Understanding Chickenpox; Brice Labruzzo et al; US Pharmacist 2012

Source-Medindia