Most Recover Fully: NIMHANS Study on Rare Post-COVID and Vaccine Brain Issues

A NIMHANS study has found rare but treatable neurological issues after Covid infection and vaccination. Most patients recovered well. Experts urge healthy lifestyles and continued research, reinforcing that vaccines remain safe and essential.

A detailed study by the National Institute of Mental Health and Neurosciences (NIMHANS) in Bengaluru has found rare neurological effects linked to COVID infection and COVID vaccination. The findings are based on real hospital data from the pandemic and the vaccination period.

These findings do not suggest vaccines are unsafe, but highlight the need for long-term monitoring, better public awareness, and more research into brain-related symptoms post-COVID.

COVID infection and neurological symptoms

Between March and September 2020, NIMHANS reviewed records of 3,200 patients admitted with neurological issues. Among them, 120 patients (3.75%) were also infected with COVID.

The common symptoms in these patients included:

• Altered consciousness (47%)
• Seizures (21%)
• Loss of smell (anosmia) (14.2%)
• Fever before symptoms (49%)

Doctors explained that COVID may affect the brain and nerves through:

• Direct viral attack on the nervous system
• Lack of oxygen (hypoxia)
• Blood clots (thrombosis)
• Overactive immune response (autoimmune effects)

Crucially, many symptoms appeared not only during active COVID but also after recovery, showing the need for long-term follow-up care.

Pre-existing neurological conditions worsened with COVID-19 

Among the 120 COVID-positive patients identified with neurological complications during the first study, 20 individuals had already been diagnosed with neurological disorders before contracting the virus. According to the NIMHANS researchers, these patients experienced a noticeable worsening of their existing neurological conditions after getting infected with COVID-19. This suggests that people with prior neurological issues may require closer monitoring during and after COVID illness.

Specific neurological conditions identified in COVID patients 

The study also recorded the exact neurological issues observed among the 120 patients. Stroke was the most common condition, affecting 43 individuals. This was followed by encephalopathy, or brain dysfunction, in 23 cases. Additionally, seven patients reported headaches, five were diagnosed with meningoencephalitis (inflammation of the brain and surrounding tissues), and three were found to have critical illness neuropathy, a condition affecting the peripheral nerves during severe infections.

What happened after vaccination?

From May to December 2021, NIMHANS tracked 116 patients who developed neurological symptoms within 42 days of getting a COVID vaccine. Among them, 29 cases (25%) were diagnosed with demyelination, a condition where the immune system damages the protective covering of nerves.

Key facts:

• 27 of the 29 cases were reported after receiving Covishield
• 2 cases were after Covaxin

Most symptoms appeared after the first dose, usually around 16 days later. The common conditions were:

• Myelopathy (spinal cord problems) – 37.9%
• Optic neuritis (eye nerve swelling) – 20.7%
• Acute Disseminated Encephalomyelitis (ADEM) – 17.2%

Important observations:

1. Most patients recovered with proper treatment
2. Those who later took a different vaccine brand or second dose under supervision did not experience major issues

Doctors believe these rare events may be triggered by individual immune responses, and because NIMHANS is a specialized hospital, detection rates may be higher than in the general population.

What the study recommends

Based on these findings, NIMHANS shared key recommendations:

• Create a national registry to track long-term neurological effects of COVID and vaccination
• Promote brain health by improving sleep, exercise, and reducing screen time
• Recognize that many Long-Covid symptoms are functional and molecular, needing tailored support
• Launch long-term studies to track effects across different organs
• Use stored biological samples to support future research

Important note: Vaccines are safe and necessary

Doctors and researchers agree that COVID vaccines save lives. They protect against severe illness, hospitalization, and death. The reported neurological effects are very rare, and most people recover completely.

The benefits of vaccination far outweigh the risks. The findings help doctors stay alert and offer better care to rare cases, not to discourage vaccination.

What The Lancet says about vaccine side effects

A trusted medical journal, The Lancet Regional Health, Western Pacific, published a study from Hong Kong about vaccine-related carditis (inflammation of the heart).

In a study of over 15 million vaccine doses, researchers found:

• A small increase in carditis cases after mRNA vaccines (Pfizer-BioNTech)
• Higher risk in young males under 30
• No increased risk with the CoronaVac (inactivated) vaccine

The researchers used a self-controlled case series (SCCS) method, which is especially useful for rare events like carditis. This means individuals acted as their own control, making the study more accurate and reliable.

The study found no evidence of increased risk from CoronaVac and emphasized the need for monitoring, not panic.

The NIMHANS and international studies help us understand how COVID and vaccines can rarely affect the nervous system. But they also prove that most people recover, and that vaccines are still safe and essential.

Being informed and careful is good but trusting science is better.