chickenpox rash

The itchy rash -- a sign of chickenpox -- is not the common springtime sight it once was, but it's far from disappeared in Lancaster County.

Prior to 1995, spring marked the arrival of “chickenpox season” in pediatrics. Since the vaccine became available, we have seen a 90 percent drop in cases of chickenpox in the United States, — however, each spring we still experience a small outbreak here in Lancaster County.

Chickenpox is an infection caused by varicella zoster virus and preferentially affects children under the age of 15. The virus can stay latent in the nervous system of the host and later in life reappear as a “shingles” infection.

The varicella vaccine may not totally prevent chickenpox, but it drastically reduces the severity, complications and duration of infection.

Quick facts

— Symptoms of chickenpox can vary, but often include one or two days of fever followed by rash outbreak. The rash typically first appears on the head and then spreads to the neck, chest and back. It is very itchy.

— Adults and immunocompromised people are at greater risk for the complications of varicella, including life-threatening pneumonia, toxic shock, necrotizing fasciitis and arthritis.

— The virus is very contagious and spreads through contact or inhalation. One study showed that susceptible people, when exposed, will contract varicella 90 percent of the time. People who have chickenpox are at their most contagious during the first few days of the rash’s appearance.

— According to the Centers for Disease Control, “Each year, more than 3.5 million cases of varicella, 9,000 hospitalizations and 100 deaths are prevented by varicella vaccination in the United States.”

— The vaccine is recommended to be given in the form of two doses, with the first one being between 9 months and 12 months, and the second between 4 years to 6 years.

pia fenimore

Dr. Pia Fenimore

— Children with chickenpox have been shown to be more susceptible to secondary infection with antibiotic-resistant staph aureus bacteria.

— Despite being vaccinated, some children will show signs of infection. This is is referred to as “breakthrough varicella.” It presents with low-grade fever and rash. The rash is typically only a few lesions, and the symptoms resolve quickly with a very minimal risk of complication.

There is debate as to how contagious a vaccinated person with the rash actually is, and it is certain they are significantly less contagious than if they were not vaccinated. Seclusion until the rash has resolved is still recommended.

— Congenital varicella syndrome is a rare disorder which affects infants whose mothers have varicella infection during the first 20 weeks of pregnancy. This disorder can include cataracts, skin abnormalities and brain malformations.

For this reason, it is recommended that all women be certain their varicella immunity is intact prior to getting pregnant.

— According to a January LNP article, 8.6 percent of Lancaster County school students are not adequately vaccinated. This is almost four times the state’s percentage. For this reason, Lancaster pediatricians remain very familiar with chickenpox and its complications.

— After age 50, it is recommended that adults receive the shingles or zoster vaccine to prevent illness from reactivation of the chickenpox virus. Reactivation is much less likely after vaccination, so the incidence of shingles is expected to decrease as vaccinated children begin to reach middle age.

Spring is here, but thanks to modern science, the former spring visits of chickenpox are rare. Yet the disease is common enough in Lancaster that keeping the above knowledge tucked away could come in handy.

  • Dr. Pia Fenimore, of Lancaster Pediatric Associates, answers questions about children's health. You can submit questions at