Why Vaccine Administration Isn’t Working

The world is in the midst of a terrible health crisis due to the COVID-19 pandemic. The United States has, for various reasons, allowed the virus to get out of control, but multiple new vaccines, developed and certified in very short time, have the capability to quickly stem the spread. The federal government promised 20 million inoculations by the end of 2020 but only 3 million or so were actually effected. Why? This is not a distribution problem – those doses were distributed to states and then to administration sites in rapid fashion.

This is an administration problem – failure to connect professional inoculators with people needing inoculations in a timely fashion. I want to address two important contributors to that failure – scheduling and stove piping – and propose very simple changes to Centers for Disease Control and Prevention (CDC) guidance to correct the deficiencies. 

Scheduling

In order to respond to the priorities established by the CDC to inoculate healthcare workers, first responders and essential workers, most vaccination centers use a reservation system, one supplied by CDC for general use. 

Why are reservations systems needed? The primary purpose of requiring reservations is to reduce patient waiting time. In the case of the segments of the population that include essential healthcare workers, wait time is very important: they have very critical duties and need to minimize work interruptions.

There is no other reason to require reservations. However, that is not well understood, as evidenced by this (mis)guidance from a healthcare provider [1]:

“Once a vial of vaccine is thawed out and opened, we have a limited amount of time in which to administer the vaccine. Because of this, we will vaccinate by appointment. When your phase arrives, we will send you a ‘ticket’ that will allow you to schedule your vaccine appointment.” 

This is not rational. To make sure all vaccine is administered after opening is to have an unlimited supply of patients, not one limited by strict reservations.

How do reservation systems work? First, time slots are established based on the expected service times. Common practice is to use conservative estimates of service times (with some padding). Next, clients/patients are invited to select from available slots and make their appointments. Finally, patients arrive (or not) for their appointments – some very early, some right on time and some late. 

For the moment, assume that all time slots are reserved. If all patients arrive precisely on time, then the gaps between servicing them are small, on average about the same as the padding used in creating the slots. If a patient arrives early, then the gap after the previous patient shifts to after the new patient. If an entire group of patients are early, then (assuming they are served right away) all that padding shifts forward in time until those patients have been served. Now there can be a considerable time gap, during which servers are idle and no inoculations are conducted. If a group of patients arrive late, again servers go idle and no inoculations happen. 

If a patient is a no-show, that time slot is lost forever; even if there are early arrivals waiting, the total number of inoculations is reduced by the number of no-shows. If not all of the time slots are reserved (a very likely situation if the patient population is restricted to very busy people) that further reduces the number of arms that get inoculated that day.

Hypothetical Situation

Take a hypothetical situation, a small clinic with one inoculator (server) who, at full speed and a constant stream of clients, could administer one shot every five minutes, giving a service capacity of 96 patients in one 8-hour shift. Suppose the reservation system applies a 2-minute padding and thus schedules an appointment every 7 minutes. Now the maximum capacity is 68.6 patients per shift (72% efficiency).

Suppose then that because of work demands and personal schedule conflicts, only 60 of the target population are able to fill slots that day. Now account for five no-shows and we are down to 55 inoculations, or 57% efficiency. In sum, using the reservation system has applied a penalty of around 40%. I would suggest that this 40% inefficiency is not too far from best performance possible. In poorer communities, challenged by communications and transportation, the inefficiency is likely to be much worse. 

A Simple Solution

The simple solution is to supply a second stream of clients that can be served during any idle times. Guidance to administration centers should require a second, unscheduled client category who are served only when there are no scheduled clients waiting for service. There should be two lines, “appointments” and “walk-ins.”

The obvious first category for walk-ins is 1b.1, seniors over age 75, the vast majority of whom are retired and have few scheduling constraints. Waiting in lines is not a hardship, as long as the result is immunity from the virus. As the vaccination program progresses nationwide, walk-in categories can be expanded in step with the CDC phase guidelines. 

Stove Piping

When an administration center receives its supply, it must determine its customer base. Hospitals will focus on its staff, public health will focus on its regular client base, doctors’ offices will schedule their regular patients, Veterans Administration hospitals will serve their staff and “eligible” veterans, and military hospitals will serve active duty.

This is natural. It’s called stove piping, and it’s wrong.

The federal government is supplying the vaccine for the benefit of the entire populace. All administration centers should be required to serve anyone and everyone eligible for the current walk-in category. Anyone in the current phase according to the CDC should be served at any center, no matter their affiliation. 

Conclusion

The United States is in crisis. We need to be pulling out all stops to get the vaccine into as many arms as possible. The more constraints we place on the administration system, the slower the vaccine rollout. Many were surprised at the slow start in 2020, but unfortunately I was not. I submit the following: If there are not long lines at every administration center 24-7, our response to the pandemic is a failure.

Reference

1. https://www.riversideonline.com/covid_19/COVID-19-Vaccine.cfm