A Guide to Fall and Winter Vaccinations: Protecting Vulnerable Populations from the Tripledemic

The fall and winter seasons pose significant healthcare threats annually, particularly for vulnerable populations and those with compromised immune systems. This issue has been further exacerbated by the emergence of what experts are calling the “tripledemic” this upcoming season, encompassing Respiratory Syncytial Virus (RSV), Influenza (Flu), and Coronavirus (COVID-19). Addressing the question of who should receive these vaccinations and when, let’s break it down.



While RSV typically leads to mild upper respiratory symptoms in healthy adults, it can cause severe illness in those with underlying medical conditions or certain risk factors. The following groups of adults aged 60 years and older are at a higher risk for severe RSV disease:

  • Lung diseases (e.g., COPD, asthma)
  • Cardiovascular diseases (e.g., congestive heart failure, coronary artery disease)
  • Neurological or neuromuscular conditions
  • Kidney disorders
  • Liver disorders
  • Hematologic disorders
  • Diabetes mellitus
  • Moderate or severe immune compromise (due to a medical condition or immunosuppressive medications)
  • Advanced age
  • Residing in nursing homes or long-term care facilities

There are two RSV vaccines licensed by the U.S. Food and Drug Administration for use in adults 60 and older in the United States:

  • Arexvy (GSK adjuvanted RSV vaccine)
  • Abrysvo (Pfizer RSV vaccine)

The CDC recommends RSV vaccination for adults aged 60 and older, with the decision to vaccinate based on shared clinical decision-making (SCDM). This approach involves healthcare providers engaging in discussions with eligible individuals to determine the appropriateness of RSV vaccination based on their individual health status and risk factors. Both vaccines work by causing an immune response that can protect you from respiratory disease if you are infected with RSV in the future.


Influenza (flu) is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. Some people, such as people 65 years and older, young children, and people with chronic health conditions, are at higher risk of serious flu complications. There are two main types of influenza (flu) viruses: types A and B. The influenza A and B viruses that routinely spread in people (human influenza viruses) are responsible for the seasonal flu epidemic each year.

The best way to reduce the risk of flu and its potentially serious complications is by getting vaccinated annually.

Routine annual influenza vaccination is recommended for all persons aged 6 months and older who do not have contraindications.

The 2023-2024 flu vaccine is quadrivalent, meaning that it protects against four different strains of the flu virus:

  • A/Victoria/4897/2022 (H1N1) pdm09-like virus
  • A/Darwin/9/2021 (H3N2)-like virus
  • B/Austria/1359417/2021-like virus (B/Victoria lineage)
  • B/Phuket/3073/2013-like virus (B/Yamagata lineage)

The specific strains of the flu virus that are included in the vaccine each year are selected by the World Health Organization (WHO) based on the strains that are most likely to circulate in the coming season.


Coronaviruses are a large family of viruses that can cause respiratory illness in humans and animals. They get their name from the “crown-like” spikes on their surface.

There are many different types of coronaviruses, but most of them only cause mild illness, similar to the common cold. However, some coronaviruses can cause more serious illnesses, such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS).

In December 2019, a new type of coronavirus was identified in Wuhan, China. This virus, called SARS-CoV-2, causes the disease COVID-19. COVID-19 can cause a range of symptoms, from mild to severe. Many people lose taste and smell senses along with typical viral prodromal symptoms including fever, chills, myalgias, and headache. Some people may experience no symptoms at all.

The CDC has compiled the following recommendations for the 2023-2024 season.

Recommendations for Children Aged 6 Months to 4 Years who are not vaccinated.

Children aged 6 months to 4 years should get two or three doses of the updated COVID-19 vaccine depending on which vaccine they receive.

Recommendations for Everyone Aged 5 Years and Older

Everyone aged 5 years and older should get 1 dose of an updated COVID-19 vaccine to protect against serious illness from COVID-19.

Children aged 5 years – 11 years who are not vaccinated or have gotten previous COVID-19 vaccine(s)

Children aged 5 years – 11 years who are unvaccinated or have previously gotten a COVID-19 vaccine before September 12, 2023, should get 1 updated Pfizer-BioNTech or Moderna COVID-19 vaccine.

People aged 12 years and older who are not vaccinated.

  • 1 updated Pfizer-BioNTech or updated Moderna COVID-19 vaccine, OR
  • 2 doses of updated Novavax COVID-19 vaccine.

It is strongly recommended to speak to your healthcare provider to evaluate options to ensure your child is up-to-date with the current guidelines and fully protected.


1. Melgar M, Britton A, Roper LE, et al. Use of Respiratory Syncytial Virus Vaccines in Older Adults: Recommendations of the Advisory Committee on Immunization Practices — United States, 2023. MMWR Morb Mortal Wkly Rep 2023;72:793–801. https://www.cdc.gov/mmwr/volumes/72/wr/mm7229a4.htm

2. Centers for Disease Control and Prevention. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices (ACIP)—United States, 2023-24, Summary of Recommendations. August 23, 2023. https://www.cdc.gov/mmwr/volumes/72/rr/rr7202a1.htm

3. National Center for Immunization and Respiratory Diseases (NCIRD), Division of Viral Diseases. August 30, 2023. https://www.cdc.gov/ncird/index.html

4. Centers for Disease Control and Prevention. Stay Up to Date with COVID-19 Vaccines. October 4, 2023. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/stay-up-to-date.html