Chart from Draft Guidance on Allocating & Targeting Pandemic Influenza Vaccine - Chart

Integrating Priorities for Pandemic Vaccination in Pandemics of Different Severity

Recognizing the need to address several important objectives for a pandemic vaccination program, vaccine should be allocated simultaneously to target groups across categories. To do so, target groups from different categories are integrated into tiers for vaccination.

The order in which target groups in Table 1 are vaccinated is defined separately for severe, moderate, and less severe pandemics (see Table 2). All groups designated for vaccination within a tier have equal priority for vaccination (see Figure 1 as an example of vaccination tiers for a severe pandemic). In general, vaccine allocation within a tier will be proportional to the populations of the targeted groups, though changes in this allocation scheme at the time of the pandemic may occur based on the impacts of the pandemic and the specific needs identified at that time.

Defining vaccination tiers differently by pandemic severity reflects differences in the threats more or less severe pandemics pose to society and individuals. Pandemics with higher case fatality rates are more likely to disrupt essential services, increase workplace absenteeism (due to illness, caring for family members, or to decrease risk of exposure), threaten public order and homeland security, and disrupt international and domestic supply chains compared with less severe pandemics. Thus, tailoring strategies to pandemic severity will best achieve national pandemic response goals and objectives. Pandemics are defined as “severe” (PSI categories 4 or 5), “moderate” (PSI category 3), and “less severe” (PSI categories 1 and 2).

It should be noted that members of occupational target groups are defined by the functions individuals within that target group are anticipated to perform over an extended period of time during the pandemic outbreak; it does not distinguish among staff performing these duties as part of their usual functions, those being reassigned to perform the function as a new response role, or those performing the function as a volunteer. It should also be noted that vaccine does not replace, but adds to other measures taken to protect the workforce and general population.