Many people are under the impression that the Netherlands is holding large stockpiles of coronavirus vaccines. In actual fact, we’re keeping the stocks of the different types of vaccine as small as possible. The size of a stock depends mainly on when new batches were last delivered. Read all about it in this article.
This article gives more information about deliveries and vaccine stocks as reported on the Coronavirus Dashboard.
The Netherlands is using different coronavirus vaccines, and we keep separate stocks of each type of vaccine. Each of these stocks consists of three parts: free stock, safety stock, and vaccines being checked. The composition of the vaccine stocks is illustrated below. Read on to find out what the different types of stock entail.
The bottom part of the figure shows the vaccines that have been delivered but are still being checked. This process takes about three days. After that, the new batches are added to the safety stock or the free stock. The Netherlands frequently gets new deliveries of vaccines, so there are always batches that are still in the process of being checked. We include these in our total stock count, even though they cannot yet be used. On the dashboard, they are described as ‘not yet available’.
The safety stock is a minimum quantity of vaccine doses that we keep on hand so that, even if a delivery is late, we do not have to cancel the next few days’ appointments. This also ensures people get their second dose on time.
The top part of the figure is the free stock – the vaccine doses currently being used for vaccination. Every time the Netherlands gets a new delivery, the total stock increases sharply. In the days that follow, the free stock is used up until the next batches are delivered.
The free stock and the safety stock together make up the available stock. The current available stock is shown on the dashboard.
We keep separate stocks of each vaccine because you can’t use different vaccines for the first and second dose. If someone’s first shot was with the Moderna vaccine, their second dose also needs to be Moderna. The same goes for BioNtech/Pfizer and AstraZeneca.
The stock count per vaccine differs because some manufacturers deliver new batches more reliably than others. And because some vaccines are used for a larger group of people than others – resulting in faster depletion of the stock.
For BioNtech/Pfizer, for instance, we always have enough doses in stock for three full days of vaccination. (Initially, this was five days.) We only need a very small safety stock of Moderna because deliveries are reliable and in small batches.
The normal safety stock of AstraZeneca is enough for five full days of vaccination. This is more than for other vaccines because AstraZeneca’s deliveries have been less stable. At the end of March, we temporarily had an excess of AstraZeneca in stock because of the temporary pause in the rollout of this vaccine, while deliveries continued to come in. The Netherlands had around 298,000 vaccines in stock at the end of March and an additional 430,000 vaccines have been delivered this week. That is much more than the safety stock and also much more than the usual free stock immediately after a new delivery. All available vaccines will now be used as quickly as possible.
In April the Netherlands is going to use up some of its safety stock in addition to the free stock. The figure below shows how this will affect vaccine stocks of BioNtech/Pfizer and AstraZeneca.
The first part of the line for BioNtech/Pfizer resembles the figure above: there’s a peak when a new delivery comes in, then stocks fall to or just below the safety stock level and are augmented again when the next delivery arrives.
The line for AstraZeneca also shows the effect of new deliveries, but the available stock is projected to be almost entirely depleted a number of times. During this period the vaccination rate will be so high that the entire safety stock will be needed in order to vaccinate everyone who has an appointment. As a consequence, some appointments may need to be cancelled if a delivery is delayed or smaller than expected. A conscious decision has been made to take this risk in order to give more people their first dose faster.