Why COVID-19 causes loss of smell and how the virus can reach the brain

Mechanisms of anosmia and brain infection in a genetic mouse model of COVID-19

NIH-funded research Icahn School of Medicine at Mount Sinai · NIH-11238999

Researchers are using a new genetically modified mouse to learn how SARS‑CoV‑2 leads to long-lasting loss of smell and spreads from the nose to the brain for people affected by COVID‑19.

Quick facts

Grant typeR01 grant
Study typeNIH-funded research
Funding institutionIcahn School of Medicine at Mount Sinai NIH-funded
Lab location1 site (New York, United States)
Project IDNIH-11238999 on NIH RePORTER

What this research studies

The team made mice that carry the human ACE2 protein in specific cell types so the virus can infect the nose in a way that mirrors people. They put virus into the nose and follow which cells in the olfactory lining and brain get infected and which changes coincide with loss of smell. The researchers turn ACE2 on or off in particular cell types, chemically remove the olfactory lining in some mice, and use imaging and sequencing to map infected cells and pathways. This approach aims to reveal the routes and cell types that let the virus reach the brain and cause long-term smell problems.

Who could benefit from this research

Good fit: People with persistent loss of smell after COVID-19 or those interested in future therapies to prevent nasal-to-brain viral spread would be the most relevant group for follow-up studies.

Not a fit: Patients without COVID-related smell loss or those needing immediate clinical treatments are unlikely to get direct benefit from this preclinical mouse research.

Why it matters

Potential benefit: If successful, this work could identify targets and strategies to prevent or treat COVID-related smell loss and stop viral spread to the brain.

How similar studies have performed: Previous animal models have shown nasal infection and anosmia, but this conditional human ACE2 mouse model is newer and allows more precise testing of which cell types drive disease.

Where this research is happening

New York, United States

Researchers

About this research

  1. This is an active NIH-funded research project — typically early-stage science, not a clinical trial accepting patient enrollment.
  2. Some NIH-funded labs run parallel clinical studies or seek volunteers for related work. To check, contact the principal investigator or institution listed above.
  3. For full project details, budget, and progress reports, visit the official NIH RePORTER page below.
Last reviewed 2026-06-10 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.