Can Vaccines Cause Brain Injuries Like Encephalitis or Encephalopathy?

Vaccines save millions of lives each year, but in rare cases, they can lead to serious side effects—including brain injuries. Children are most at risk for vaccine-related neurological injuries such as encephalopathy or encephalitis, both of which involve brain inflammation and can result in long-term complications.

What is the Difference Between Encephalitis and Encephalopathy?

While both conditions affect the brain, they are distinct:

• Encephalitis is inflammation of the brain, often caused by a viral infection like West Nile virus or herpes simplex.

• Encephalopathy refers to temporary or permanent brain dysfunction, damage, or disease. Severe or prolonged encephalitis can lead to encephalopathy.

Can Vaccines Cause Brain Damage?

Yes, although rare, certain vaccines have been associated with brain injuries. The U.S. government’s Vaccine Injury Compensation Program (VICP) recognizes this risk and offers compensation for qualifying cases of vaccine-induced encephalopathy.

The Vaccine Injury Table lists the following vaccines as potential causes:

• Pertussis-containing vaccines (DTaP, TDaP, DTP-Hib)

• MMR vaccines (MMR, MMRV, MM)

Even if your injury isn’t linked to one of these vaccines, you can still file a VICP claim—with medical evidence showing the vaccine caused the injury.

Symptoms of Vaccine-Induced Encephalitis

Symptoms typically develop within two weeks of vaccination. Watch for:

• Fever and flu-like symptoms

• Muscle weakness or pain

• Loss of coordination

• Fatigue and confusion

• Seizures

• Changes in consciousness

Timing matters:

• Following a pertussis vaccine, encephalitis symptoms usually appear within 72 hours.

• Following an MMR vaccine, encephalitis symptoms typically appear within 5–15 days.

Signs of Vaccine-Induced Encephalopathy

In children under 18 months:

• Reduced consciousness lasting over 24 hours (with or without seizure)

• Persistent irritability (3+ hours)

• Limpness, poor muscle tone

• Difficulty waking up

• Lack of responsiveness or blank stare

In individuals over 18 months:

• Significant mental status changes (lasting 24+ hours)

• Memory loss, confusion, personality changes

• Seizures with loss of consciousness

How Are Encephalitis and Encephalopathy Diagnosed?

Doctors may use several tests, including:

• Brain imaging (MRI or CT scan)

• Lumbar puncture (spinal tap)

• EEG (electroencephalogram)

• Blood tests

• Brain biopsy (in rare cases)

Treatment Options for Brain Inflammation After Vaccination

Treatment depends on severity. Mild cases may require:

• Rest

• Anti-inflammatory medications

• Hydration

Severe cases may involve:

• Seizure medications

• IV fluids

• Breathing support

• Physical, speech, and occupational therapy

• Psychotherapy

Can You Receive Compensation for Vaccine-Related Brain Injuries? 

If encephalitis symptoms persist longer than six months, they may result in chronic encephalopathy, marked by long-term cognitive, behavioral, or neurological impairments.

The National Vaccine Injury Compensation Program allows victims to recover damages without suing healthcare providers or pharmaceutical companies. You may be eligible for:

• Medical expenses (past and future)

• Pain and suffering

• Lost income and earning potential

• Legal fees (paid separately by the program)

Let Our Vaccine Injury Attorneys Help You Seek Justice

Winning a VICP claim takes experience and commitment. Our vaccine injury attorneys at Shannon Law Group will gather evidence, build a compelling case, and advocate for your family every step of the way.

Call us today at (312) 578-9501 or fill out the online form below to schedule your free, no-obligation consultation.