By: Rebecca Samuel, PharmD Candidate c/o 2022 and Pallak Sharma, PharmD Candidate c/o 2022
It is flu shot season! That’s a phrase that causes almost every pharmacy staff member to take a deep breath. Amid the pandemic, flu shot season is busier than ever and it is directly affecting pharmacies across the country. In order to prepare for an expected increase in demand, hospitals and community pharmacies are stockpiling more flu vaccines than ever. Community pharmacies like Rite Aid and Walgreens have purchased more flu vaccines this year in comparison to previous years to meet the demand. Rite Aid purchased 40% more vaccines and Walgreens reports it expects a 30% to 50% jump in demand for flu shots and other immunizations. ¹
The flu vaccines are manufactured by multiple pharmaceutical companies and they prepared for this increase in demand as well. It is projected that vaccine manufacturers will prepare 194 to 198 million doses of the influenza vaccine throughout the 2020-2021 flu season. However, these projections are subject to change throughout the season. There are a variety of vaccines that will be prepared throughout the season. Ninety-nine percent of the vaccines prepared will be quadrivalent which means they have four different antigens present in the vaccine (the same three that are in the trivalent vaccines, plus one more). Approximately 87% of the vaccines will be thimerosal-free or thimerosal-reduced, or in other words, preservative free, and approximately 20% will be egg free. ²
So why the spike in demand? An annual flu vaccine is recommended for almost everyone 6 months and older. It is one of the best ways to reduce flu illnesses, hospitalizations and death from flu. The coming months are especially known as flu season, but COVID-19 adds another layer of uncertainty. For this reason, getting a flu shot is more important than ever so that people can stay healthy, out of the hospital, and help ease the burden on our health care system. The flu is a contagious illness that affects the nose, throat, lungs, and other parts of the body. It can spread quickly from one person to another and can cause mild to severe illness, and at times can lead to death. The respiratory symptoms of the flu can seem similar to the coronavirus as well, which can definitely be cause for concern. ³ A severe case of either the flu or COVID-19 can lead to hospitalization. Doctors are also worried about the potential impact of having both the flu and coronavirus since there is such an overlap in symptoms. However, with the flu vaccine available, we are able to reduce this risk and reduce the strain on hospitals in this pandemic.
But even without the stress of a pandemic, flu season has still affected millions of people in previous years. Between 9 million and 45 million people are infected with the flu each year, and between 140,000 and 810,000 are hospitalized, according to Center for Disease Control and Prevention (CDC) estimates. In 2018, the U.S. recorded its highest death toll from the flu in recent history, with 80,000 deaths. ⁴ The seasonal flu vaccine protects against the influenza viruses that research indicates will be most common during the upcoming season. Most flu vaccines in the United States protect against four different flu viruses (“quadrivalent”); an influenza A (H1N1) virus, an influenza A (H3N2)virus, and two influenza B viruses. For the senior population, those that are 65 years of age or older, a different set of vaccines are offered.
There is a quadrivalent flu shot with an adjuvant available for seniors. The adjuvant in this particular combination provides an immune-boosting response for this specific population. ⁵ Another version of the quadrivalent flu shot is also available for seniors which is provided as a higher dose. This means that the high-dose quadrivalent vaccine contains four times the antigen than the standard quadrivalent flu shot given for those under the age of 65. Both the adjuvant and high-dose versions of the vaccine are beneficial to people who are 65 years and older because this population tends to have weaker immune systems compared to those who are younger and are therefore more at risk for infection and flu-related deaths. Those who are 65 years and older account for approximately 70-85% of flu-related deaths and approximately 50-70% of flu-related hospitalizations each flu season. Since older adults have lower immune responses, this can contribute to lower vaccine effectiveness. Research has gone into developing these flu vaccines specifically for this age group to provide better immunity. The CDC states the first step to preventing the flu is receiving the vaccine and therefore the CDC does not suggest one vaccine above another. ⁶
Vaccines help develop immunity by imitating an infection that almost never causes illness. The purpose of this is to stimulate production of T-lymphocytes and antibodies. Sometimes, after getting a vaccine, the body is trying to build immunity, so minor symptoms such as fever can occur; this is normal and can be expected. Once the imitation infection goes away, the body is left with a supply of “memory” T-lymphocytes, as well as B-lymphocytes that will remember how to fight that disease in the future. However, it typically takes a few weeks for the body to produce T-lymphocytes and B-lymphocytes after vaccination. Therefore, it is possible that a person infected with a disease just before or just after vaccination could develop symptoms and get a disease, because the vaccine has not had enough time to provide protection. ⁷
This is why getting the flu shot is so important at this time of year. Even if you receive the flu shot right now, it will take almost two weeks to be effective, leaving people susceptible to infection. The CDC recommends that the public get vaccinated in early fall, and ideally by the end of October to provide protection through the bulk of flu season. The CDC says getting vaccinated too soon, in July or August, for example, is associated with less protection later in flu season. This information has not stopped the influx of patients. Patients were seen coming in for flu shots as soon as they became available, as early as August.
The stress of the COVID-19 pandemic does not stop at the patient-level. Manufacturers have increased their projected supplies, pharmacies have increased their inventories, and hospitals must be prepared for the possibility of individuals that have COVID-19 and the flu at the same time. It is essential to receive the flu vaccine as soon as possible in order to optimize the health of the public and ease the burden on our healthcare workers. By getting a flu shot an individual not only protects themselves, but the people they are around as well. ¹
- Runwal P. Pharmacies are Bracing for a Surge in Demand for Flu Shots Amid the Covid-19 Pandemic. Stat News. https://www.statnews.com/2020/09/25/flu-shots-covid-19-pandemic-demand/. Published 9/25/2020.
- Centers for Disease Control and Prevention. Seasonal Influenza Vaccine Supply for the U.S. 2020-2021 Influenza Season https://www.cdc.gov/flu/prevent/vaxsupply.htm. Published 10/15/2020
- NYS Department of Health. What You Should Know About the Flu https://www.health.ny.gov/diseases/communicable/influenza/seasonal/. Published 9/01/2020.
- Centers for Disease Control and Prevention. Disease Burden of Influenza. https://www.cdc.gov/flu/about/burden/index.html. Published 10/05/2020.
- Centers for Disease Control and Prevention. Key Facts About Seasonal Flu Vaccine. https://www.cdc.gov/flu/prevent/keyfacts.htm. Published 9/11/2020
- Centers for Disease Control and Prevention. Fluzone High-Dose Seasonal Influenza Vaccine.https://www.cdc.gov/flu/prevent/qa_fluzone.htm. Published 9/03/2020
- Centers for Disease Control and Prevention. Understanding How Vaccines Work. https://www.cdc.gov/vaccines/hcp/conversations/understanding-vacc-work.html. Published 8/17/2018