Most people think of chickenpox as a childhood illness — and, for the most part, they’re right.
In the early to mid-1990s, just before vaccination against chickenpox became widespread, the infection predominantly affected children, according to the Centers for Disease Control and Prevention (CDC). (1)
But vaccination has dramatically changed how chickenpox affects the entire population. By 2016, the CDC says, 90 percent of children had received at least the first dose of the two recommended doses of the chickenpox vaccine by age 2. (5)
And among teenagers ages 13 to 17, at least 85 percent had received both recommended doses of the vaccine as of 2016. (6) Overall, since the national chickenpox vaccine program started in 1995, the rate of new cases of chickenpox has decreased about 97 percent. (6).
This new disease landscape means that unlike in the past, when nearly everyone got chickenpox before they reached adulthood, most young adults now haven’t had the disease, and most have been vaccinated.
Yet as the numbers above show, a small but significant amount of younger adults haven’t been vaccinated and haven’t had the disease — in numbers far greater than seen in the past.
This means that even as the risk of catching chickenpox is as low as it has ever been, the number of potentially at-risk adults in the population may be growing larger. This is not considered to be a significant public health concern, but it may be an individual concern for you or someone you know.
Here’s what you should know about how chickenpox affects adults, and what you can do to limit your risk of infection and possible complications.
Which Adults Are at Risk for Chickenpox?
While chickenpox was never common in adults, it’s become even less common since widespread vaccination began in 1995, according to Deborah S. Clements, MD, the chair of the department of family and community medicine at Northwestern University’s Feinberg School of Medicine in Chicago.
“Where we see it is in people who were not vaccinated after 1995, and in those who are immunocompromised,” says Dr. Clements. This second group potentially includes people with cancer, autoimmune diseases, HIV/AIDS, and other conditions.
In some cases, a disease itself may weaken your immune system, such as in HIV/AIDS and certain types of cancer. In other cases, a treatment for your disease can have this effect — such as chemotherapy for cancer or immunosuppressive drugs for an autoimmune disease like rheumatoid arthritis.
The following groups of adults are considered at elevated risk for chickenpox and its complications:
- People with a weakened immune system (due to a health condition or medical treatment)
- People who take steroid medications, such as for asthma
- Pregnant women who haven’t had chickenpox (2)
Chickenpox is highly contagious, and you can get it just by being in the same room as someone who has it. (3)
The disease is “spread by respiratory droplets,” Clements notes. This means you’re more likely to get chickenpox from someone who is coughing or sneezing, but it’s possible that even talking could spread the disease.
You’re more likely to get chickenpox if you’re in sustained contact with someone with the disease, or with groups that are more likely to carry it, such as unvaccinated children. (3)
Because you can’t get the chickenpox vaccine while you’re pregnant, it’s especially important for pregnant women who haven’t been vaccinated or had the disease to limit their exposure risk.
“Anyone who is pregnant should avoid contact with people who have chickenpox or a shingles outbreak,” Clements emphasizes.
Shingles is a reactivation of the chickenpox virus that occurs later in life. A person with shingles cannot pass shingles to another person but can pass the varicella zoster virus — the virus that causes both chickenpox and shingles — to a person who has not had chickenpox or been vaccinated against it. The risk is low: A person would need to be in prolonged contact with another’s shingles lesions (sores) to get the virus.
Chickenpox Symptoms in Adults
When adults get chickenpox, it tends to cause symptoms in the same way as when the disease affects children — up to a point.
This means that in the beginning, a fever and some upper respiratory symptoms (such as a runny nose) typically develop before a chickenpox rash sets in, according to Clements. These symptoms usually begin 10 to 21 days after you’re exposed to the chickenpox virus.
The rash that develops next is usually the telltale sign of chickenpox. It typically starts as small red bumps, which then progress to small blisters over large areas of your skin. (2,3)
A typical chickenpox blister is sometimes described as resembling “‘a dewdrop on a rose petal,’ because it’s a small, clear blister on a red surface on the skin,” says Clements. “That helps differentiate it from lots of other kinds of rashes.”
Within 5 to 7 days, the blisters usually break and develop a crust that turns into a scab. These scabs fall off when the skin under them has healed, usually within 20 days of the first appearance of your rash. (4)
Potential Chickenpox Complications in Adults
Adults who get chickenpox are at greater risk for complications, especially pneumonia (lung infection).
Chickenpox pneumonia “can be very, very serious,” says Clements. “It’s a viral pneumonia that is not easily treated because of how the virus behaves. We can use an antiviral to a certain extent, but it’s not really very effective.”
This type of pneumonia tends to develop and worsen rapidly. The good news, says Clements, is that “we hardly see it anymore.”
Another major concern, says Clements, is that a pregnant woman can pass problems on to her child by catching chickenpox.
Getting chickenpox in the earlier part of your pregnancy can cause low birth weight or birth defects in your newborn, such as limb abnormalities.
And if you get chickenpox right before or after giving birth, this can be passed on as a life-threatening infection in your newborn. (2)
Prevention and Treatment
The best way to prevent chickenpox, for most people, is to get vaccinated.
You can even gain protection by getting the vaccine within 3 to 5 days after being exposed to the chickenpox virus. At this stage, the vaccine may prevent an infection, or it may result in less severe symptoms and a lower risk of complications. (2)
If you do develop chickenpox symptoms as an adult, it’s important to recognize them early so that you can get treated with an antiviral drug, says Clements. This is done so that you don’t go on to develop more complicated symptoms, she says.
Be sure to call ahead to your doctor’s office about your symptoms, since you may be asked to use a different entrance at your appointment to avoid exposing others to chickenpox.
As far as self-care is concerned, Clements recommends taking ibuprofen (Advil) or acetaminophen (Tylenol) for discomfort as needed, as well as taking an oatmeal or colloid bath to help reduce itching.
You’ll pose an infection risk to others from shortly before you develop your rash until all your blisters have crusted over, for a total of about 7 to 10 days. During this time, Clements says, you should stay home from work and keep other outings to a bare minimum.
If you have to be around other people for a sustained period while you’re contagious, Clements recommends wearing a face mask.
When it comes to chickenpox prevention, the best news is that because of widespread vaccination, you’re unlikely to get it.
During earlier periods of her career, Clements says, “It was not at all uncommon to have residents work in the pediatric wards and come down with chickenpox.” But now, thanks to the vaccine, “it’s very, very rare to see it anymore.”