Navigating pneumococcal vaccination in adults
ABSTRACTWith two nonequivalent vaccines available and different recommendations for different patient populations, vaccination against Streptococcus pneumoniae can be confusing. Here we try to clarify the situation.
KEY POINTS
- At highest risk of invasive pneumococcal disease are people who are immunocompromised, very young, or very old.
- Pneumococcal polysaccharide vaccine-23 (PPSV23) covers more serotypes of S pneumoniae than pneumococcal conjugate vaccine-13 (PCV13), but the latter induces a stronger antibody response.
- The combination of both vaccines in sequence produces a better antibody response than either vaccine alone.
- The Advisory Committee on Immunization Practices now recommends that immunocompromised and asplenic adults who need pneumococcal vaccination receive both vaccines, preferably PCV13 first, followed by PPSV23 8 weeks later. Those who have already received PPSV23 can receive PCV13 after at least 1 year has passed.
- People with asplenia or immunocompromising conditions should receive a second dose of PPSV23 at least 5 years after the first dose.
- Vaccination schedules and information are available from the US Centers for Disease Control and Prevention at www.cdc.gov.
AT-RISK PATIENT POPULATIONS
Since both PPSV23 and PCV13 are approved for use in adults, it is important to understand appropriate indications for their use. The ACIP recommends pneumococcal vaccination in adults at an increased risk of invasive pneumococcal disease: ie, people age 65 and older, at-risk people ages 19 to 64, and people who are immunocompromised or asplenic.
A more robust antibody response has been shown with PCV13 compared to PPSV23 in healthy people.5 Of note, when PPSV23 is given before PCV13, there is a diminished immune response to PCV13.11,12 Therefore, unvaccinated people who will receive both PCV13 and PPSV23 should be given the conjugate vaccine PCV13 first. (See Commonly asked questions.)
ADULTS AGE 65 AND OLDER: ONE DOSE EACH OF PCV13 AND PPSV23
Before September 2014, the ACIP recommended one dose of PPSV23 for adults age 65 and older to prevent invasive pneumococcal disease.13 With evidence that PCV13 also produces an antibody response and is clinically effective against pneumococcal pneumonia in older people, the ACIP now recommends that all adults age 65 and older receive one dose of PCV13 and one dose of PPSV23.3, 14
Based on antibody studies, the ACIP recommends giving PCV13 first and PPSV23 12 months after.11,12 Patients who received PPSV23 at age 65 or older should receive PCV13 at least 1 year after PPSV23 (Figure 2).3,14 Patients who had previously received one dose of PPSV23 before age 65 who are now age 65 or older should receive one dose of PCV13 at least 1 year after PPSV23 and an additional dose of PPSV23 at least 5 years after the first dose of PPSV23 and at least 1 year after the dose of PCV13.3 Patients who received a dose of PCV13 before age 65 do not need an additional dose after age 65.
The Centers for Medicare and Medicaid Services have updated the reimbursement for pneumococcal vaccines to include both PCV13 and PPSV23. Patients can receive one dose of pneumococcal vaccine followed by a different, second pneumococcal vaccine at least 11 full months after the month in which the first pneumococcal vaccine was administered.15
AT-RISK PATIENTS AGES 19 TO 64
Before 2012, the ACIP recommended that patients at risk, including immunocompromised patients and those without a spleen, with cerebrospinal fluid leaks, or with cochlear implants, receive only PPSV23 before age 65.13 In 2010, 50% of cases of invasive pneumococcal disease in immunocompromised adults were due to serotypes contained in PCV13.16 Additionally, according to CDC data from 2013, in adults ages 19 to 64 at risk of pneumococcal disease, only 21.2% had received pneumococcal vaccine.17 With information on epidemiology, safety, and efficacy, as well as expanded FDA approval of PCV13 for adults in 2011, the ACIP updated its guidelines for pneumococcal immunization of adults with immunocompromising conditions in October 2012.16 The updated guidelines now include giving PCV13 to adults at increased risk of invasive pneumococcal disease.16
Adults under age 65 at risk of invasive pneumococcal disease can be further divided into those who are immunocompetent with comorbid conditions, and those with cochlear implants or cerebrospinal fluid leak. (Table 1).16
Patients with cochlear implants or cerebrospinal fluid leaks should receive one dose of PCV13 followed by one dose of PPSV23 8 weeks later. If PPSV23 is given first in this group, PCV13 can be given 1 year later.
Immunocompetent patients with comorbid conditions, including cigarette smoking, chronic heart, liver, or lung disease, asthma, cirrhosis, and diabetes mellitus, should receive one dose of PPSV23 before age 65 (Table 1).16
IMMUNOCOMPROMISED AND ASPLENIC PATIENTS
Immunocompromised patients at risk for invasive pneumococcal disease include patients with functional or anatomic asplenia or immunocompromising conditions such as HIV infection, chronic renal failure, generalized malignancy, solid organ transplant, iatrogenic immunosuppression (eg, due to corticosteroid therapy), and other immunocompromising conditions.16 Patients on corticosteroid therapy are considered immunosuppressed if they take 20 mg or more of prednisone daily (or an equivalent corticosteroid dose) for at least 14 days.16 These immunocompromised patients should receive one dose of PCV13, followed by a PPSV23 dose 8 weeks later and a second PPSV23 dose 5 years after the first.16
The time between vaccinations is also important. If PCV13 is given first, PPSV23 can be given after at least 8 weeks. If PPSV23 is given first, PCV13 should be given after 12 months. The time between PPSV23 doses is 5 years (Figure 3).16
ADDRESSING BARRIERS TO PNEUMOCOCCAL VACCINATION
In 2013, only 59.7% of adults age 65 and older and 21.1% of younger, at-risk adults with immunocompromising conditions had received pneumococcal vaccination.17 Healthcare providers have the opportunity to improve pneumococcal vaccination rates. The National Foundation for Infectious Diseases (www.nfid.org) summarized challenges in vaccinating at-risk patients and recommended strategies to overcome barriers.18
Challenges include the cost of vaccine coverage, limited time (with competing priorities during office appointments or hospitalizations), patient refusal, and knowledge gaps.
Strategies to overcome barriers include incorporating vaccination into protocols and procedures; educating healthcare providers and patients about pneumococcal disease, vaccines, costs, and reimbursement; engaging nonclinical staff members; and monitoring local vaccination rates. However, the most important factor affecting whether adults are vaccinated is whether the healthcare provider recommends it.
AN OPPORTUNITY TO IMPROVE
In the last 30 years, great strides have been made in recognizing and preventing pneumococcal disease, but challenges remain. Adherence to the new ACIP guidelines for pneumococcal vaccination in immunocompromised, at risk and elderly patients is important in reducing invasive pneumococcal disease.
Healthcare providers have the opportunity to improve pneumococcal vaccination rates at outpatient appointments to decrease the burden of invasive pneumococcal disease in at-risk populations. A comprehensive understanding of the guideline recommendations for pneumococcal vaccination can aid the provider in identifying patients who are eligible for vaccination.
Adult pneumococcal immunization rates are low due to missed opportunities. Healthcare providers can improve these rates by viewing every patient encounter as a chance to provide vaccination.
