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Call to Action: the Dangers of Influenza and COVID-19 in Adults

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Call to Action: the Dangers of Influenza and COVID-19 in Adults Call to Action The Dangers of Influenza and COVID-19 in Adults with Chronic Health Conditions October 2020 Experts urge all healthcare professionals to prioritize influenza vaccination to help protect adults with chronic health conditions during the COVID-19 pandemic The recommendations in this Call to Action are based on discussions from an Call to Action August 2020 Roundtable convened by the National Foundation for Infectious The Dangers of Influenza Diseases (NFID). The multidisciplinary and COVID-19 in Adults with group of subject matter experts Chronic Health Conditions explored the risks of co-circulation and co-infection with influenza and SARS-CoV-2 viruses in adults with chronic Overview health conditions from the perspective While every influenza (flu) season is unpredictable, of their specialized areas of medicine the 2020-2021 season is characterized by an and discussed strategies to protect unprecedented dual threat: co-circulation of these vulnerable populations. influenza and the novel coronavirus (SARS-CoV-2) that causes COVID-19. Moreover, there is concern Experts agreed that higher levels of that co-circulation and co-infection with influenza influenza vaccination coverage during and COVID-19 viruses could be especially harmful, the 2020-2021 influenza season could particularly among adults at increased risk of reduce the number of influenza-related influenza-related complications. hospitalizations, helping to avoid Influenza poses serious health risks to adults unnecessary strain on the US healthcare with certain chronic health conditions including system during the COVID-19 pandemic, heart disease, lung disease, and diabetes. The so that healthcare facilities have the increased risk of influenza-related complications capacity to provide care to patients includes the potential exacerbation of underlying with COVID-19. health condition(s), as a result of influenza-related inflammation that may persist long after the acute infection. Of particular concern, adults with chronic health conditions have an increased risk 1 of long term complications, such as heart attacks Annual influenza vaccination during the 2020-2021 and strokes, after experiencing acute influenza influenza season is more important than ever due or COVID-19. to the simultaneous threat posed by the COVID-19 pandemic. Vaccination against influenza will have Annual influenza vaccination is essential to help added benefits—not only will it help to prevent prevent infection, mitigate severe disease and influenza, reduce disease severity, and prevent related complications, and alleviate additional strain serious influenza-related complications, but it will on an overburdened US healthcare system. While also help to reduce strain on the US healthcare recommended in the US for all individuals age six system, due to the COVID-19 pandemic. months and older, annual vaccination is especially important for adults with chronic health conditions, Burden of Influenza in US Adults older adults, and underserved minority populations with Chronic Health Conditions to avoid exacerbation of chronic health conditions, permanent physical decline, or death. Even in Influenza is a contagious viral infection associated cases when influenza vaccination does not prevent with a significant disease burden. Each year in the infection, it can reduce the severity of disease and US, influenza is responsible for millions of illnesses, prevent serious influenza-related complications, hundreds of thousands of hospitalizations, and tens such as heart attacks or strokes. During the 2018- of thousands of deaths.2 2019 influenza season, it is estimated that influenza Although all individuals can be impacted by vaccination prevented 4.4 million illnesses, 58,000 influenza, the burden is greatest in adults with hospitalizations, and 3,500 deaths (Figure 1).1 certain chronic health conditions including heart Figure 1: Benefits of Influenza Vaccination1 Approximately 49% of the US population chose to get an influenza vaccine during the 2018-2019 influenza season, and this prevented an estimated: 4.4 million 58,000 3,500 influenza illnesses influenza hospitalizations influenza deaths More than the population About the number Equivalent to saving of Los Angeles of students at Ohio about 10 lives per day over State University the course of the year 10 LIVES A DAY 2 disease, lung disease, and diabetes, as well as adults several weeks past the acute infection stage. age 65 years and older and underrepresented This inflammation often worsens an individual’s minority populations, who often have underlying underlying disease and can lead to heart attack health conditions. It is important to note that adults or stroke, even after the acute illness has been with chronic health conditions are at increased risk resolved—adding to the risk of mortality (Figure 3). of influenza-related complications, hospitalization, exacerbation of underlying disease, and death, Figure 3: Potential Effects of Influenza even when health conditions are well-controlled, Infection on Adults with Chronic due to the effects of influenza-related inflammation Health Conditions INCREASED that may occur long after acute influenza infection. MORTALITY As the dual threat of influenza and COVID-19 INCREASED FRAILTY converge, experts urge all healthcare professionals to prioritize influenza INCREASED vaccination for adults with chronic health HOSPITALIZATION conditions and other vulnerable patients. EXACERBATED CHRONIC DISEASE During the 2019-2020 influenza season, 92.6 percent of adults hospitalized with influenza-related complications had at least one underlying medical CHRONIC INFLUENZA 3 DISEASE condition. The most commonly reported underlying INFECTION medical conditions in patients hospitalized for influenza include heart disease, diabetes, obesity, and chronic lung disease (Figure 2). While adults with chronic health conditions are at increased risk of severe illness and influenza- Figure 2: Selected Underlying Medical related complications every year, the COVID-19 Conditions of Laboratory Confirmed pandemic may further increase the risk of adverse Influenza Hospitalizations for the outcomes. Many of the underlying health conditions 4 2019-2020 Influenza Season that make adults vulnerable to influenza are also Asthma 23% linked to increased vulnerability to SARS-CoV-2 infection, severe disease outcomes, increased Chronic lung disease 36% hospitalization, and mortality. During the 2020-2021 Heart disease 47% influenza season, the possibility of co-infection with influenza and SARS-CoV-2 is an even greater cause Metabolic disorder (diabetes) 43% for concern particularly for adults with chronic Obesity 40% health conditions, despite the limited data currently available on interactions between the two viruses 5 An often-overlooked effect of influenza infection and the potential consequences. is the inflammatory reaction that can last for 3 Annual influenza vaccination is a key prevention While every year presents a challenge to increase strategy to protect all adults, and especially influenza vaccination coverage, the 2020-2021 those with chronic health conditions. Although season will have additional unprecedented influenza vaccination has been shown to prevent obstacles due to the COVID-19 pandemic. Innovative hospitalization and influenza-related mortality, strategies are necessary to ensure influenza vaccination rates remain suboptimal and have vaccines are safely administered during the stagnated around 50 percent among US adults.6 COVID-19 pandemic. Less than half of adults age 50 to 64 years receive an annual influenza vaccine, and this pattern Preparing for an Influenza Season has been consistent for the past decade.7 While During the COVID-19 Pandemic influenza vaccination rates are higher among adults age 65 years and older, approximately one-third Anticipated Burden of Influenza and COVID-19 still remain unvaccinated each year—well below During the 2020-2021 Season US public health goals.8 According to a recent NFID COVID-19 has had an adverse impact on routine survey, nearly one-quarter of individuals at high risk vaccinations. Due to COVID-19-related stay-at-home for influenza-related complications said they did orders, adult vaccination rates in the US as of May not intend to get vaccinated against influenza.9 2020 had declined by 12 to 63 percent (varying by state) in comparison to the previous year, with nearly half of adults age 50 years and older not receiving recommended vaccinations.10 Influenza Key Challenges for the vaccination rates may also suffer during the 2020- 2020–2021 Influenza Season 2021 season. ▪ Increasing vaccine coverage among As of September 2020, more than 200,000 adults with chronic health conditions in individuals in the US died from COVID-19, the presence of a dual threat of influenza with new cases being reported daily.11,12 The and COVID-19 trajectory of the COVID-19 pandemic is uncertain ▪ Reducing strain on the US healthcare system and partly depends on personal protection, that adults with chronic health conditions infection control, and social distancing often rely upon measures. The pattern bears resemblance ▪ Addressing logistical concerns, including to the novel H1N1 influenza A virus that limited emergency room/hospital capacity, emerged in the spring of 2009, where cases issues with access to traditional vaccination increased until summer, decreased somewhat sites, and limited opportunities to vaccinate during the summer, and spiked before the start adults with chronic health
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