How is Chickenpox Diagnosed?


The rash caused by the chickenpox virus is generally recognized immediately by a doctor or nurse when examining a patient. The rash, along with a few questions about additional symptoms, is usually all that is needed to diagnose chickenpox in children.

The chickenpox rash with begin slowly and will spread from the face and trunk to the outer areas of the body. It will often come with a fever and tiredness at the same time. The rash, or bumps, will appear gradually over a period of a few days. They will blister and eventually scab over in the order in which they arrived. This can take a week or more.

It is important to know whether or not the chickenpox virus is causing a rash. For this reason, a healthcare professional must check any unexplained rash, especially one accompanied by flu-like symptoms.

How is Chickenpox Treated?


A virus causes chickenpox and therefore cannot be treated by antibiotics. Antiviral medication might be used in cases where patients are at greatly increased risk of complications, but this is generally not necessary. It will usually run its course on its own, making the best treatment for chickenpox one that makes the patient the most comfortable. 

The following can help to relieve the major discomforts of chickenpox:

  • Lukewarm baths or cool, wet compresses every 3 to 4 hours
  • Oatmeal bath products
  • Patting skin dry instead of rubbing the skin
  • Calamine lotion on itchy skin (being careful to avoid the eye area)
  • Pain relieving creams for sores on sensitive and genital area skin
  • Over-the-counter anti-itch medications taken by mouth
  • Mittens or gloves to avoid scratching while sleeping
  • Keeping fingernails trimmed short and clean to avoid blister infections
  • Over-the-counter fever reducer/pain reliever (aspirin free for children)



Chickenpox is very contagious. Someone with chickenpox can spread the virus through coughing or sneezing (by putting droplets into the air). It can also be spread through contact with mucus, saliva, and blister fluid from an infected person.

A vaccine for chickenpox is available and is effective in preventing chickenpox in over 90% of the people who receive it. The vaccination is administered in two doses, beginning at the age of 12 to 15 months, with a booster between 4 and 6 years old. Older children and adults can receive the vaccine, with doses 1 month apart.

Someone with chickenpox is contagious beginning one to two days before developing the characteristic chickenpox rash. Once infected, someone with chickenpox is contagious until all blisters have scabbed over.

Chickenpox generally runs its course in 1 to 2 weeks.

Chickenpox is extremely contagious. Up to 90% of people close to an infected person who are not immune or vaccinated will become infected.

Chickenpox begins with flu-like symptoms such as tiredness, headache, fever, and sometimes stomachache and/or lack of appetite. It often goes undiagnosed at this stage, until the telltale chickenpox rash develops 2 to 5 days after infections.

It is believed that the varicella-zoster virus, the cause of chickenpox, was brought to the Americas in the 15th century by European explorers and settlers.

To be fully protected from the chickenpox virus two doses of the vaccine are recommended. One dose of the varicella vaccine is 82% effective at preventing any form of the virus. Two doses provide over 90% effectiveness.

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Trust NewYork-Presbyterian for Chickenpox Treatment

A healthcare professional, such as a primary care physician, should evaluate any flu-like symptoms accompanied by a skin rash. NewYork-Presbyterian is here for you with same-day critical-needs appointments and early, late, and weekend hours to allow for easy scheduling.

We accept most insurance. Knowing your symptoms is important when visiting your NewYork-Presbyterian medical provider as this will help your doctor make the correct diagnosis.