Where It Comes From

Chickenpox (Varicella): Where It Comes From, Who It Affects, Treatment, Future Issues, and the Link to Shingles

***Medical Disclaimer***

This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. I am not at MD, RN, or LVN. This is not a substitute for care from a licensed healthcare professional. If you suspect chickenpox—especially in a newborn, during pregnancy, or in someone with a weakened immune system—contact a clinician promptly. Seek urgent care for trouble breathing, severe headache, confusion, persistent high fever, dehydration, widespread redness/warmth of the skin (possible bacterial infection), or rash involving the eyes.***

Introduction

Chickenpox—also called varicella—is a highly contagious viral illness best known for its itchy, blister-like rash. For many people, chickenpox is a childhood illness that resolves without lasting problems. However, chickenpox can be more severe in infants, adolescents, adults, pregnant people, and immunocompromised individuals. It also has an important long-term connection: after chickenpox resolves, the virus can remain dormant in the body and later reactivate as shingles (herpes zoster).

Because vaccination has dramatically reduced chickenpox cases in many countries, some adults today may be less familiar with what chickenpox looks like, how it spreads, and when it becomes medically urgent. This article explains where chickenpox comes from, which age groups are most affected, how it’s treated, potential future issues, and how it relates to shingles.

Where Chickenpox Comes From (Cause and Virus Basics)

Chickenpox is caused by the varicella-zoster virus (VZV), a member of the herpesvirus family. VZV spreads easily from person to person and can cause outbreaks in households, schools, and other close-contact settings.

How it spreads

VZV is transmitted primarily through:

- Respiratory droplets/aerosols (breathing, coughing, sneezing)

- Direct contact with fluid from chickenpox blisters

A person with chickenpox is typically contagious from 1–2 days before the rash appears until all lesions have crusted over.

Incubation period

After exposure, symptoms usually develop in about 10–21 days (often around 14–16 days).

Age Groups and Who Is Most at Risk

Children

Historically, chickenpox was most common in young children, and many cases were mild. Typical childhood chickenpox includes fever, fatigue, and an itchy rash that resolves over about a week.

Adolescents and adults

Chickenpox tends to be more severe in adolescents and adults, with:

- Higher fever

- More extensive rash

- Greater risk of complications (including pneumonia)

Infants and newborns

Newborns and young infants can be at higher risk, especially if:

- The mother develops chickenpox near the time of delivery

- The infant is premature or has underlying health issues

Pregnancy

Chickenpox during pregnancy can be serious for the pregnant person and may pose risks to the fetus/newborn depending on timing. Any suspected chickenpox in pregnancy warrants prompt medical evaluation.

Immunocompromised individuals

People with weakened immune systems (from certain medications, cancer treatment, transplant medications, advanced HIV, etc.) are at higher risk for severe disease and complications and should seek medical care quickly if exposed or symptomatic.

Signs and Symptoms

Chickenpox often begins with general “viral” symptoms, followed by the rash.

Early symptoms (may occur 1–2 days before rash)

- Fever

- Fatigue

- Headache

- Reduced appetite

- General malaise

Rash characteristics

The chickenpox rash is classically described as appearing in “crops,” meaning new lesions continue to appear over several days. Lesions typically progress through stages:

1. Red spots (macules/papules)

2. Fluid-filled blisters (vesicles) — often very itchy

3. Crusting/scabbing

A hallmark is seeing lesions in different stages at the same time.

Common distribution

The rash often starts on the trunk (chest/back) and spreads to the face and extremities, though patterns vary.

Diagnosis

Clinicians often diagnose chickenpox based on:

- The characteristic rash pattern

- Exposure history

- Symptoms and timing

If the presentation is atypical, laboratory testing (such as PCR testing of lesion samples) may be used.

Treatment: What Helps and What to Avoid

Treatment depends on age, health status, and severity.

Supportive care (common for otherwise healthy children)

- Fluids to prevent dehydration

- Rest

- Fever management with appropriate medications as advised by a clinician

- Itch relief (e.g., soothing baths, topical preparations, antihistamines when appropriate)

Important: Avoid giving aspirin to children or teenagers with viral illnesses due to the risk of Reye’s syndrome.

Antiviral therapy (selected cases)

Antiviral medication (such as acyclovir) may be considered, especially for:

- Adolescents and adults

- People at higher risk of complications

- Immunocompromised individuals

- Certain cases where treatment can be started early

Because antiviral decisions depend on timing and medical history, this should be guided by a clinician.

Preventing skin infection

Scratching can break the skin and increase the risk of bacterial infection. Helpful strategies include:

- Keeping nails short

- Using itch-control measures

- Keeping skin clean

- Watching for signs of infection (increasing redness, warmth, swelling, pus)

Potential Complications and “Future Issues”

Most healthy children recover fully, but complications can occur.

Short-term complications

- Bacterial skin infections (from scratching)

- Dehydration

- Pneumonia (more common/severe in adults and high-risk groups)

- Neurologic complications (rare, but can include cerebellar ataxia or encephalitis)

Long-term issue: the virus stays in the body

After chickenpox resolves, VZV can remain dormant in nerve tissue. Later in life, it can reactivate as shingles.

Chickenpox and Shingles: The Connection

What shingles is

Shingles (herpes zoster) is caused by reactivation of VZV years or decades after chickenpox. It typically causes:

- Localized burning/tingling pain

- A one-sided blistering rash following a nerve pathway

- Risk of persistent nerve pain (postherpetic neuralgia), especially in older adults

Why shingles happens later

Reactivation becomes more likely with:

- Older age (especially 50+)

- Immune suppression

- Certain medical conditions or treatments

Can you “catch” shingles from someone with chickenpox?

A person with shingles can transmit VZV to someone who is not immune, causing chickenpox in that person (not shingles). Similarly, a person with chickenpox can transmit VZV to a non-immune person.

Prevention

Varicella (chickenpox) vaccination

Vaccination has significantly reduced chickenpox cases and complications in many settings. Vaccination recommendations vary by country and individual medical circumstances, so readers should consult local public health guidance and their clinician.

Post-exposure steps (high-level)

If someone is exposed to chickenpox and is at high risk (pregnancy, immunocompromised, newborns), clinicians may consider specific preventive measures. Because timing is critical, medical advice should be sought promptly after exposure.

Shingles vaccination (later-life prevention)

For eligible adults, shingles vaccination reduces the risk of shingles and complications such as postherpetic neuralgia. This is separate from childhood varicella vaccination and is typically discussed for older adults and certain higher-risk groups.

When to See a Doctor

Seek medical advice promptly if chickenpox is suspected in:

- Adults

- Pregnant people

- Newborns/infants

- Immunocompromised individuals

- Anyone with chronic lung disease or significant underlying illness

Seek urgent care if there are signs of severe illness or complications, such as:

- Difficulty breathing or chest pain

- Confusion, severe headache, stiff neck

- Persistent high fever

- Severe dehydration (very low urine output, lethargy)

- Rapidly worsening redness, warmth, swelling, or pus around lesions

- Rash involving the eyes

Here are adult chickenpox (varicella) complications

Chickenpox complications in adults (more detail)

Chickenpox is often mild in children, but adults are more likely to have severe disease and complications. Risk is higher in people who are pregnant, smoke, have chronic lung disease, or have weakened immune systems (for example from steroids, chemotherapy, transplant medications, or advanced HIV).

1) Varicella pneumonia (most important adult complication)

Varicella pneumonia is one of the most serious complications in adults and can be life‑threatening.

- Symptoms: worsening cough, shortness of breath, chest pain, rapid breathing, low oxygen, high fever, and feeling very ill—often developing a few days after the rash starts.

- Who’s at higher risk: adults (especially smokers), pregnant people, and immunocompromised individuals.

- Why it matters: it can progress quickly and may require hospitalization and antiviral treatment.

2) Secondary bacterial skin and soft‑tissue infections

Scratching can break the skin and allow bacteria (commonly Staphylococcus aureus or Streptococcus pyogenes) to cause infection.

- Signs: increasing redness, warmth, swelling, pus, worsening pain, or fever after initial improvement.

- Potential severity: can range from mild impetigo to cellulitis; rarely can become invasive (serious bloodstream infection).

3) Neurologic complications (uncommon but serious)

Adults can rarely develop nervous system involvement, including:

- Encephalitis (brain inflammation): severe headache, confusion, drowsiness, seizures.

- Cerebellitis/ataxia (coordination problems): unsteady gait, dizziness.

- Meningitis (lining around brain/spinal cord): severe headache, stiff neck, light sensitivity.

These require urgent evaluation.

4) Hepatitis and other organ involvement (rare)

Varicella can occasionally cause inflammation of organs such as the liver (hepatitis) or other systemic complications, particularly in immunocompromised patients.

- Clues: severe abdominal pain, jaundice, unusual bleeding/bruising, marked fatigue.

5) Dehydration and severe systemic illness

Adults may have higher fever and more extensive rash, leading to:

- Dehydration (especially if oral intake drops)

- Severe fatigue and inability to maintain normal activities

This can be dangerous in older adults or those with other medical conditions.

6) Complications in pregnancy (adult-specific concern)

Chickenpox during pregnancy can be serious for the pregnant person (including pneumonia). Depending on timing, it can also pose risks to the fetus/newborn, so suspected varicella in pregnancy should be evaluated promptly.

7) Higher likelihood of scarring

Adults often have more intense inflammation and scratching, increasing the chance of permanent scars or pigment changes.

8) Long-term issue: shingles later in life

After recovery, VZV remains dormant and can reactivate later as shingles, with possible long-lasting nerve pain (postherpetic neuralgia), especially with older age.

“When to seek urgent care” (adults)

Seek urgent care if an adult with chickenpox develops shortness of breath, chest pain, persistent high fever, confusion, severe headache, stiff neck, trouble walking, dehydration, or rapidly worsening redness/pus around lesions.

Sincerely,

-Coach James

JHenderson Training & Consulting

References (Peer-Reviewed and Major Clinical Guidance)

1. Gershon AA, Breuer J, Cohen JI, et al. Varicella zoster virus infection. Nature Reviews Disease Primers. 2015;1:15016.

2. Arvin AM. Varicella-zoster virus. Clinical Microbiology Reviews. 1996;9(3):361–381.

3. Heininger U, Seward JF. Varicella. The Lancet. 2006;368(9544):1365–1376.

4. Kawai K, Gebremeskel BG, Acosta CJ. Systematic review of incidence and complications of herpes zoster: towards a global perspective. BMJ Open. 2014;4:e004833.

5. Oxman MN, Levin MJ, Johnson GR, et al. A vaccine to prevent herpes zoster and postherpetic neuralgia in older adults. New England Journal of Medicine. 2005;352(22):2271–2284.

6. Lal H, Cunningham AL, Godeaux O, et al. Efficacy of an adjuvanted herpes zoster subunit vaccine in older adults. New England Journal of Medicine. 2015;372(22):2087–2096.

7. Centers for Disease Control and Prevention (CDC). Varicella (Chickenpox): Clinical Overview / Prevention guidance. (Clinical guidance; not peer-reviewed, included as a widely used public health reference.)