Chickenpox is a common illness caused by the varicella-zoster virus. It is a painful infection that occurs in the skin, followed by blisters that spread on the face and neck, followed by painful itching. All of the classic symptoms include rash, high fever, and runny nose. An infected person usually needs to stay home from school or work for up to two weeks. And, if you get chickenpox and you are allergic to the virus, you can die from the infection.
But, you can also get chickenpox without any of these symptoms. If you experience fatigue, low fever, and a slight rash, you can get chickenpox.
Research on children in the U.S infected with varicella zoster virus
One study found that up to 15 percent of children in the U.S. are infected with varicella zoster virus, but less than one percent of them develop chickenpox. The reason that varicella-zoster virus is so common is because most people get the chickenpox vaccination. People older than 15 are usually given the varicella-zoster vaccine. The chickenpox vaccine is not as effective at preventing varicella-zoster virus infection as the measles vaccine, but it is still much safer than not getting the vaccine at all.
A team of researchers from Vanderbilt University Medical Center wanted to see if the measles vaccine could protect children with varicella-zoster virus infections from getting the chickenpox virus. In order to do this, they measured how much measles vaccine was needed to prevent an infection. They found that children vaccinated with a single dose of the measles vaccine needed eight times more measles vaccine to prevent a typical case of chickenpox. The researchers also found that children who did not get the measles vaccine had to receive 40 doses of the vaccine to prevent the illness. Children with very mild varicella-zoster virus infections who received four doses of the measles vaccine still experienced 40-fold higher average costs of the vaccination, compared to a child who did not receive a single dose of the measles vaccine.
The researchers also compared how much money each child needed to recover after they had the chickenpox vaccine and after they recovered from the disease. They found that, for children with moderate disease, the cost of recovering from the chickenpox vaccine was only three times as much as recovering from the disease without the vaccine.
“What we found was very surprising,” said Dr. Benjamin Green, study co-author and assistant professor of Pediatrics at Vanderbilt. “The cost of recovery from varicella-zoster vaccine was less than the cost of recovery from disease in children with moderate disease.”
“One reason this is happening may be that the vaccine has fewer side effects,” added Dr. Claire McCarthy, study co-author and associate professor of Pediatrics at Vanderbilt.
The researchers found that, after recovering from the disease, children had about one-third of the viral antibodies they would have if they had not received the vaccine. In addition, children who recovered from varicella-zoster virus infections needed fewer antibiotics and antiviral drugs than children who never recovered from the virus. The results suggest that the chickenpox vaccine can help children recover much more quickly from the infection.
“I’m happy to see the results of this study confirm what we know from decades of clinical experience, that the chickenpox vaccine is safe, it works well and it can save lives,” said Dr. William Schaffner, M.D., Director of the National Center for Immunization and Respiratory Diseases at the CDC.
The researchers analyzed data from 49 children (average age 4.9 years old) who were treated at Vanderbilt Pediatric Hospital. All the children had experienced a mild to moderate illness of chickenpox and were not vaccinated. They reported their symptoms and how long it took them to recover. They were tested for the varicella-zoster virus and sent to Vanderbilt for diagnostic tests to confirm that they had the virus.
The findings were consistent with other studies showing that the measles vaccine is more effective than not receiving the vaccine. The chickenpox vaccine, which used to be recommended only for children between 12 and 18 months old, is now recommended for children as young as 12 months old, depending on the age of the child’s mother. The chickenpox vaccine is also recommended for anyone born after 1957. In addition, people who have had a severe case of chickenpox are encouraged to receive the vaccine.
“We are happy to recommend this vaccine to adults,” said Dr. McCarthy. “We should be, as a country, just as happy to recommend the vaccine to adults as we are to recommend the vaccine to children. It saves lives and has fewer side effects.”
The authors note some limitations to the study, including that they did not determine the exact reason for the cost difference between recovering from the vaccine and recovering from the disease. The researchers note, however, that the cost data in their study are in line with the pricing of the vaccines, and there are likely several reasons why costs are lower in children who had the vaccine.
The study was funded by the Centers for Disease Control and Prevention (grants 5P50CH003909, P30-MR004831 and P30-MR004831-07-03).
About the Vanderbilt University School of Medicine
Vanderbilt University School of Medicine is one of the nation’s leading academic centers for biomedical research and graduate medical education. It is ranked No. 1 for primary research by U.S. News & World Report and among the top 10 most innovative research institutions as ranked by the journal Nature in its Nature Innovation Index.
The School of Medicine is affiliated with the Vanderbilt University Medical Center, which is ranked No. 16 in the nation by U.S. News and World Report and is among the top 25 most innovative medical centers in the country. The School of Medicine is a leader in medical education, research, patient care and community service. More information is available at www.medschool.vanderbilt.edu.