Invasive pneumococcal disease (IPD) is a serious, but preventable, disease that causes significant morbidity and mortality. “Vaccines against Streptococcus pneumoniae have been recommended for adults for decades, but uptake of these vaccinations is suboptimal,” says Ashley M. Wilde, PharmD, BCPS-AQ ID. Studies show that vaccination rates are well below national goals despite many opportunities to vaccinate patients who meet ACIP and CDC criteria for vaccination against S pneumoniae.

For a study published in Open Forum Infectious Diseases, Dr. Wilde and colleagues identified and highlighted specific healthcare settings where most patients with IPD could have been vaccinated to prevent disease. “Our health system has a robust inpatient and outpatient presence within our community,” Dr. Wilde explains. “We serve many patients with comorbidities or conditions that place them at increased risk for IPD. Our study assessed if patients with IPD had an opportunity to be vaccinated within our health system prior to getting sick.”

The retrospective analysis examined the percentage of adults with IPD who received recommended pneumococcal vaccinations, the frequency of missed opportunities for vaccination by setting, and the rate of in-hospital mortality. A missed opportunity for vaccination was defined as a visit to an outpatient office, immediate care center, ED, or hospital admission before developing IPD where no ACIP-recommended pneumococcal vaccination was administered. Patients who had not visited a facility prior to developing IPD were considered to have no missed vaccination opportunities.

More Than Half of Patients With IPD Had Missed Vaccine Opportunities

The study team identified 229 cases of IPD, 219 of which met at least one pneumococcal vaccination criteria while 10 met none of the criteria. “More than half of patients with IPD had a missed opportunity to be vaccinated within our healthcare system prior to developing IPD,” says Dr. Wilde. “Only 14% of patients with IPD were documented as being up to date with recommended pneumococcal vaccines.”

Smoking, chronic heart disease, chronic lung disease, and age older than 65 were the most common IPD risk factors, according to the study. Roughly 78% of patients had multiple risk factors for IPD, highlighting the likelihood that rising numbers of risk factors correlates with a higher risk for developing IPD (Table). Of note, none of the study patients with six or more risk factors for IPD were vaccinated.

“Recent discussions on vaccines nationwide have focused on the politics of COVID-19 vaccine mandates and the safety of products available through emergency use authorization,” Dr. Wilde says. “However, despite the long history of safety and efficacy of pneumococcal vaccines, the low percentage of fully vaccinated patients seen in our study was especially discouraging given that the observed mortality rate was approximately 20%.”

Efforts Needed to Reinforce Uptake of Pneumococcal Vaccinations

According to Dr. Wilde, there is now a diffusion of responsibility for offering vaccines to at-risk individuals. “In areas where pneumococcal vaccines are widely available, clinicians may assume that another healthcare setting will take responsibility for offering vaccines,” she says. “In our study, half of patients with IPD visited an outpatient office or had an inpatient admission prior to developing IPD. As such, pneumococcal vaccination efforts should be reinforced with updated and streamlined recommendations in both outpatient and inpatient settings.”

A better understanding of the downstream consequences and missed opportunities may help reinforce the importance of vaccinations. Additional investments in adult vaccination services may help foster a culture in which every eligible patient is educated on the importance of pneumococcal vaccinations at every point of contact. “The entire healthcare community needs access to simplified vaccine registry data and a reimbursement model that eliminates logistical barriers to providing vaccines to adults,” Dr. Wilde says. “Effective interventions and strategies are needed to overcome these barriers. Future studies should explore ways to improve confidence in the efficacy and safety of pneumococcal vaccines in adults because the consequences of IPD can be severe.”