COVID-19 and its impact on high-risk groups

There have been a few COVID-19 updates in the news in the last month. It is important for people who are at high-risk of serious illness to be aware of these changes, including adults aged 65 years and older, pregnant people, children aged 5 years and under, and people with weakened immune systems due to medical conditions or immunosuppressive treatments.

CDC updates respiratory illness guidance

CDC has issued updated guidance on how to manage exposure to respiratory viruses, including COVID-19, flu, and respiratory syncytial virus (RSV).¹ The goal of the update is to establish one set of simple guidelines to follow when you get sick with any of these illnesses.

The most significant change is the removal of the recommended 5-day isolation period for COVID-19 infection. The new recommendations state that you should stay home while you are sick with any respiratory illness, and that if your symptoms are mild and improving and it has been 24 hours since you have had a fever, you can return to work and to regular activities. The removal of the 5-day isolation period could be a safety concern if you are at high risk as it increases the risk of exposure to COVID-19.

If you are in a high-risk group, preventing infection is crucial. The CDC update emphasized the importance of following well-known core prevention strategies, including staying up to date with immunizations and wearing a mask to reduce exposure. CDC recently announced that people aged 65 and older should get an additional dose of updated COVID-19 vaccine this spring.²

High-risk individuals should also consider being prepared before getting sick.³ This includes talking with your healthcare provider about whether you may have any health conditions that could prevent you from taking medication to treat COVID-19. It is crucial to consult your physician for testing and treatment as soon as you develop symptoms, as treatments that reduce the risk of severe illness from COVID-19 must be taken within 5 days after symptoms begin to be effective.

FDA authorizes drug to prevent COVID-19 infection

For people who are immunocompromised and over 12 years of age, the FDA recently granted an emergency use authorization for a monoclonal antibody drug called Pemgarda™ to prevent COVID-19 infection.⁴ It is intended to be used prior to exposure to the virus and cannot be administered if a person has an active COVID-19 infection. Pemgarda™ attaches to the spike protein of SARS-CoV-2, the virus that causes COVID-19, and prevents the virus from entering the body’s cells. It is given as an infusion in a medical setting and takes about an hour to complete. Immunocompromised people can get a dose of the medication as often as every three months.

Long COVID may lead to cognitive decline

Some people who have been infected with the virus that causes COVID-19 can experience long-term effects from their infection, known as Long COVID. Long COVID is defined as signs, symptoms, and conditions that continue or develop after acute COVID-19 infection. A recent study published in the New England Journal of Medicine presented some worrying findings about COVID-19 infection and declining cognitive performance, often referred to as “COVID brain fog.”⁵ This large study involved 800,000 people in England who had COVID-19 between March 2020 and March 2022.

Some of the findings were expected based on previous studies — people who had long-term COVID symptoms, lasting for 12 weeks or more, had a loss of cognitive ability that was equal to six IQ points, compared with people who never had COVID. Common difficulties included trouble with reasoning, thinking, and memory. Unexpectedly, the study showed that even people who had quickly recovered from COVID still had a loss of cognitive ability equivalent to three IQ points.

They also found that people who were admitted to intensive care had the most significant loss (nine IQ points) and that getting reinfected with COVID-19 decreased cognition by two more IQ points. Importantly, the results showed that COVID-19 vaccination provided some protection against cognitive loss.

There are still many questions about COVID-19 and cognitive decline, including the precise causes of cognitive defects, how to best prevent these losses from occurring, and the identification of effective treatments for those with persistent cognitive issues.

References

1. CDC Newsroom. CDC https://www.cdc.gov/media/releases/2024/p0301-respiratory-virus.html (2024).
2. Clinical Guidance for COVID-19 Vaccination | CDC. https://www.cdc.gov/vaccines/covid-19/clinical-considerations/interim-considerations-us.html (2023).
3. Respiratory Virus Guidance. https://www.cdc.gov/respiratory-viruses/guidance/respiratory-virus-guidance.html (2024).
4. Research, C. for D. E. and. Emergency Use Authorizations for Drugs and Non-Vaccine Biological Products. FDA https://www.fda.gov/drugs/emergency-preparedness-drugs/emergency-use-authorizations-drugs-and-non-vaccine-biological-products (2024).
5. Hampshire, A. et al. Cognition and Memory after Covid-19 in a Large Community Sample. New England Journal of Medicine 390, 806–818 (2024).