Favipiravir May be an Effective COVID-19 Treatment
November 25, 2020 09:00pm
By Sara Karlovitch, Assistant Editor
Pneumonia is a serious public-health issue both in the United States and globally.
Pneumonia is a serious public-health issue both in the United States and globally. Every year in the United States, approximately 1 million individuals seek hospital care and 50,000 die of pneumonia, and the majority of those affected are adults 65 years and older.1Pneumococcal bacteria comprise over 90 strains and are the most common cause of bacterial pneumonia.2Although all strains can cause illness, only 10 strains are responsible for 62% of invasive pneumococcal disease globally.3The disease is spread by droplets in the air and through direct contact with saliva or mucus. In addition to pneumonia, pneumococcal bacteria can also cause meningitis, bacteremia, otitis media, and sinusitis; the disease is responsible annually for the deaths of approximately 18,000 US adults ages 65 and older.2,4Pneumococcal pneumonia, specifically, is fatal for 1 of every 20 people, and pneumococcal meningitis and pneumococcal bacteremia are fatal for 1 of every 6 people.4
As health care providers, we are on the frontlines, where we can educate patients on the risks of pneumonia and the methods for preventing it. As cold and flu season begins to wind down, healthy patients may make more of an effort to inquire about recommended preventive vaccinations. Additionally, in the retail clinic setting, we may encounter patients who do not receive regular physicals and consistent primary and preventive care. It is our responsibility to educate our community and encourage risk reduction strategies to those who may benefit from it — primarily through vaccination.
As providers, how can we know how to provide the best protection possible for our patients and our community? Two vaccines exist to protect against pneumococcal pneumonia, which often causes confusion in both patients and providers: pneumococcal conjugate (PCV13 or Prevnar13) and pneumococcal polysaccharide (PPSV23 or Pneumovax23). Both are indicated for adults 65 and older, and one or more is recommended for adults aged 19 to 64 with certain risks; however, both vaccinations cannot be administered during the same office visit. In addition to pneumococcal vaccination, we can also lower a patient’s risk for pneumonia by encouraging vaccination against influenza, pertussis, varicella, measles, and Haemophilus influenzae type B.1
The first pneumococcal polysaccharide vaccine was licensed in the United States in 1977 and contained antigens from 14 different types of pneumococcal bacteria. PPSV23 was licensed in 1983 and replaced the previous polysaccharide vaccine.3It now protects against the 23 most common pneumococcal serotypes and is used in adults and select children older than 2 years.5According to the CDC, studies on PPSV23’s effectiveness have reported somewhat mixed results in evaluating for prevention of pneumococcal pneumonia in target populations. In immunocompetent older adults and adults with chronic illnesses, 50% to 80% effectiveness in prevention of pneumonia has been demonstrated, with somewhat lower effectiveness in immunosuppressed and very old populations.6Revaccination with PPCV23 has been shown to induce a “persistent functional antibody response in healthy middle-aged and older adults”5and therefore an additional dose is often indicated.
The first pneumococcal conjugate vaccine, called PCV7, was licensed in the United States in 2000 and protected against 7 different serotypes of pneumococcal bacteria.3In 2010, PCV13, which provided protection from an additional 6 serotypes, was licensed and replaced PCV7.3PCV13 is approved for infants, children, and select adult populations, for whom the Advisory Committee on Immunization Practices (ACIP) began recommending PCV13 in 2012.5The recommendation for routine vaccination for all adults 65 and older with PCV13 was made in November 2014, which is helpful to know when patients report that they received a pneumococcal vaccine before 2012 yet are unsure which one they received.3
Risks and Recommendations
The rate of pneumonia in the United States varies considerably among populations and can be divided into 3 different risk groups based on age and health status. Based on age alone, infants, young children, and older adults (65 and older) are most at risk. Additionally, adults aged 19 to 64 years with certain medical conditions are also at increased risk.
Adults aged 19 to 64 years with competent immune systems and no chronic medical conditions are at average risk. Neither PCV13 nor PPSV23 is recommended in this population.
Adults aged 19 to 64 years with chronic heart disease, chronic lung disease, diabetes, alcoholism, and chronic liver disease (Online Figure 1) are at increased risk. Cigarette smokers in this age group are also at increased risk, which is a fairly new recommendation; in 2008, the ACIP found information to suggest that smokers are at increased risk for pneumococcal disease.3This is important for pharmacists and clinicians to consider because adult smokers who do not receive regular preventive care often present with acute illnesses, so we have a unique opportunity to educate and vaccinate these patients. It is worth noting that this recommendation does not apply to users of smokeless tobacco or to former smokers without lung disease, as these factors are not found to increase the risk of contracting pneumococcal disease.3
In this increased risk category, only PPSV23 is recommended before age 65. ACIP recommends that, upon turning 65, patients in this population receive PCV13 followed by PPSV23 1 year later. The 2 doses of PPSV23 should be given at least 5 years apart.
The highest risk category arguably comes with the most questions regarding vaccination schedule. It includes all adults 65 years and older and adults 19 to 64 years who have compromised immune systems. Both PCV13 and PPSV23 are recommended for this population. In immunocompetent adults aged 65 and older who are vaccine naïve, PCV13 is recommended first, followed by PPSV23 at least 1 year later.8If the patient is younger than 65 years, a second dose of PPSV23 should be given 5 years after the initial dose of PPSV23, and a final dose should be given after the patient turns 65 (again, 5 years after the most recent dose of PPCV23). Adults with immune-compromising conditions should still receive PCV13 first, but PPSV23 should be given 8 weeks later.8Any additional doses of PPSV23 in immunocompromised patients should be given at the routine 5-year interval. If PPSV23 was given first, PCV13 should be given at least 1 year later regardless of immune status.
Online Figure 1 presents pneumococcal vaccine timing for adults 65 years and older, for both immunocompetent and immunocompromised adults. Online Figure 2 presents the vaccination schedule for adults aged 19 to 64 years at increased risk who require 1 dose of PPSV23. Online Figure 3 presents the vaccination timing for adults aged 19 to 64 years who have the highest risk and require both PCV13 and at least 1 dose of PPSV23.9
When administering a vaccination, among the most common questions we receive as providers is what adverse effects the patient can expect. The most common adverse effects associated with PCV13 are redness, pain, and swelling at the injection site and mild, systemic symptoms such as low-grade fever, chills, fatigue, and headache.4The most common adverse effects associated with PPSV23 are redness and pain at the injection site, occurring in about 50% of patients.4Systemic symptoms such as fever are rare and occur in <1% of patients.4Life-threatening allergic reactions from both PCV13 and PPSV23 are very rare.
Immunization Contraindications and Other Considerations
PCV13 is contraindicated in anyone who has had a serious, life-threatening reaction to a dose of PCV7 or PCV13, or with a serious allergy to any ingredient in the vaccine.4Additionally, anyone with a history of serious reactions to diphtheria-containing vaccines (such as Tdap or Dtap) should not receive PCV13 because it is conjugated to a diphtheria-toxoid.2Similarly, PPSV23 should not be given to anyone who has a history of a serious, life-threatening reaction to the vaccine or a serious allergy to any ingredient in the vaccine.4No contraindication exists to PPSV23 in patients with a history of reaction to diphtheria-containing vaccine. It is important to note that the ACIP does not recommend against simultaneous administration of PPSV23 and Zostavax, despite Merck’s recommendation in the Zostavax package insert.3They can be given on the same day, or separated by any time interval between the 2.
Many patients will ask prior to administration if the vaccine will be covered by their insurance. Always instruct the patient to check with their insurance provider on potential out-of-pocket costs and in-network providers. Medicare Part B fully covers the cost of both vaccines when administered 12 months apart.4
Pneumococcal Vaccination Pearls
• When both vaccines are indicated, PCV13 should be given first.9
• PCV13 is recommended first because studies have found the immune response to be stronger when administered in this order.3
• PCV13 should be given 1 year prior to PPSV23 in immunocompetent adults, but 8 weeks prior in adults with certain medical conditions (defined as immunocompromised, CSF leaks, or having cochlear implants).9A complete table of recommendations based on specific medical conditions is available on the CDC website.7
• If either vaccine is given earlier than recommended, it should not be repeated.7
• “Unknown” vaccination history should be treated as “No” vaccination history.5Extra doses will not cause harm to the patient.3
• If indicated, it is safe to give either PCV13 or PPSV23 with inactivated influenza vaccine.2
• If a second PPSV23 dose is indicated, it should be given at least 5 years after the first.7
• Only 1 dose of PPSV23 should be administered to a patient 65 years or older.7
• Both pneumococcal vaccines are safe to give during pregnancy.3
Test Your Understanding
1. Marilyn is 68 years old, has no chronic medical conditions, and has never received a pneumonia vaccine before.
2. Michael is 66 years old and has a history of diabetes, hypertension, and hyperlipidemia. He received PPSV23 at age 60.
3. Katherine is 72 years old and is presenting for her annual influenza vaccine. She received PPSV23 at her annual checkup 6 months ago, but has not yet received PCV13.
4. Joseph is 67 years old and has a history of a kidney transplant at age 60. He was vaccinated with both Prevnar13 and PPSV23 after his transplant at age 61.
5. Dennis is 70 years old and believes he received PPSV23 from his primary care provider (PCP) “about 10 years ago because he was a smoker.” His PCP also gave him PCV13 when he turned 65.
6. Daniel is 68 years old with a history of COPD and received PCV13 at age 60, but forgot to return 1 year later for his PPCV23. He finally received a dose of PPSV23 at age 65.
7. Elizabeth is 70 years old. She states she received PCV13 at age 65 and PPCV23 at age 66. She is asking if she needs a “booster” dose of PPCV23 now that it has been 5 years.
8. Ryan is 26 years old and presents to the clinic for a preemployment physical. He has no chronic medical problems, but reports a history of “childhood asthma.” He also smokes half a pack of cigarettes per day.
9. Mattie is 55 years old and recently started taking adalimumab (Humira) for rheumatoid arthritis. She has never had a pneumonia vaccine before.
10. James is 60 years old and has no chronic medical problems. He is a former smoker and states he quit 5 years ago. He presents to the clinic for the influenza and Tdap vaccination because he is about to become a grandfather in a few weeks. He wants to do whatever he can to protect his grandchild and asks when he should receive a pneumonia vaccination.
1. Administer PCV13 to Marilyn today and instruct her to return for PPSV23 in 1 year or less.
2. Give Michael PCV13 today, and instruct him to return for PPSV23 in 1 year or less.
3. Instruct Katherine to return in 6 months for PCV13.
4. Joseph needs 1 additional dose of PPSV23, which can be given today since it has been longer than 5 years.
5. Dennis needs a dose of PPSV23 today.
6. No vaccine is needed for Daniel.
7. No booster needed for Elizabeth— her vaccination is complete.
8. Ryan needs PPCV23.
9. Mattie should receive PCV13 today and PSV23 in 8 weeks. She will need another PPSV23 5 years after her first PPSV23, and another after she turns 65, with a 5-year interval between the 2nd and 3rd dose.
10. James falls into the average risk category and therefore vaccination is not indicated until he turns 65.
Pneumococcal pneumonia remains an important source of illness, hospitalization, and fatality in the United States, especially in adults 65 years and older. Providers in retail clinics and pharmacists play an important role in educating the community and offering vaccination when it is indicated, especially to those at increased risk. We also have the unique opportunity of educating at-risk adults who are not established with a PCP and may otherwise not receive these important vaccinations. With thorough understanding and application of the principles of pneumococcal vaccination, we can make a significant contribution to the health and well-being of our community.
Anna Butcher is a practicing Family Nurse Practitioner for Minute Clinic in Chalfont, Pennsylvania. She has been a Family Nurse Practitioner for 4 years and has worked in primary care and as a RN, pediatric cardiology and nephrology. She received her BSN from Drexel University in Philadelphia and her MSN from George Washington University in Washington, DC.