Fall season is upon us in the US – changing of the color of the leaves, cooling temperatures, and the standard respiratory viral illness season.  While the changing of seasons is a joyous occasion, it needs to be addressed with the proper precautions. This year, the season’s risk of viral infections have expanded significance – not only is infection with influenza virus a risk, but cases of COVID-19 are rising, and respiratory syncytial virus (RSV) is spreading. Additionally, Streptococcus pneumoniae is a bacteria that can cause pneumonia, for which there is a vaccine to prevent infection from some types. Vaccinations for these four potential respiratory infections are available, are effective, are safe and are recommended by the ATS and other professional healthcare societies to protect you and our population overall from getting sick from these potentially serious respiratory infections. November 5th-11th is the PAR week for Practical Aspects of Vaccination. We invite you to participate in the webinars scheduled and browse the resources provided. Our goal is to provide you with up-to-date and factually correct information about vaccines. 

Vaccines have been a potent asset in the medical armament against disease.  With the first successful vaccination created in 1796 against smallpox, these vaccines leverage the human immune system to protect the body from diseases.  In fact, vaccines have saved more human lives than any other medical invention in history.[WHO]  This week we are highlighting the vaccines that have been instrumental in preventing respiratory infections.  These vaccines are marvels of science by their common approach to ignite the immune system to be prepared to fight infection but tackle this role using different characteristics of the virus and different mechanisms of action to stimulate host immunity.

Influenza vaccines are formulated annually to protect against four main groups of influenza Type A and Type B viruses, based on circulating virus and epidemiologic trends of how the viruses are spreading. Influenza vaccines are inactivated (killed) virus, live attenuated (weakened) virus, or recombinant synthetic vaccines.  While initial formulations were egg-based injections, subsequent preparations have included non-egg derivatives and nasal sprays.

Pneumococcal vaccines target multiple (but not all) serotypes of Streptococcal pneumoniae infection. The available pneumococcal vaccines are categorized as polysaccharide (T-cell independent) and conjugate protein-bound (T-cell dependent) vaccines.

COVID-19 vaccines were developed during the early stages of the pandemic using existing technology to target this novel coronavirus. There were three vaccines available in the United States – two mRNA vaccines that replicated viral antigens in the host patient and one viral vector vaccine.  With further study of the efficacy of the vaccines, the mRNA vaccines for COVID-19 have been updated to target multiple variants of the virus with the bivalent formulation for booster protection for this third winter season since the COVID-19 vaccines have been introduced.

Most recently, the respiratory syncytial virus (RSV) vaccination has been approved for adults. RSV is a virus that can cause respiratory illness and often displays the same seasonality as influenza season.  This RSV vaccine combines a specific RSV protein with an adjuvant carrier protein to maximize immune response to the RSV protein. 

While these vaccines are available and have been shown to save lives through the immunologic protection that they elicit, these vaccines have still not reached every eligible person for a number of reasons.  For some patients, medical contraindications, such as serious allergies to a vaccine, may exclude some people from getting some vaccinations.  For others, skepticism behind the science that led to the vaccination production or hesitancy with exposing themselves to newer vaccines can be the reasons that some invoke when declining vaccines.  Yet others are affected by limited access to vaccines and limited access to health education to be able to understand the vital role of vaccines to promote health.   This PAR week will provide valuable resources for providers and patients to inform on the practical aspects of vaccination. 

[WHO] World Health Organization. 2023. Accessed 10/16/2023

[CDC] Centers for Disease Control and Prevention.  2021.  Accessed 10/17/2023.  

Vidya Krishnan, MD MHS

Professor of Medicine, Case Western Reserve University

Pulmonary, Critical Care and Sleep Medicine

CWRU / The MetroHealth System