The CDC’s Covid-19 vaccination card, annotated

Nearly 170 million people have been vaccinated against Covid-19 in the United States — which means the same amount have been handed a version of the Centers for Disease Control and Prevention’s white record card.

The CDC’s vaccination card is likely to be the primary proof of vaccination going forward as the US continues loosening pandemic restrictions. Much of the information on the card is straightforward, but other parts, such as the vaccine lot number, point to key details that are less widely understood.

We’ve annotated a sample CDC vaccination card below in order to better go through the details of the vaccination process.

1) The manufacturer

In the US, there are three Covid-19 vaccines authorized for emergency use: Pfizer-BioNTech, Moderna and Johnson & Johnson. Pfizer and Moderna are two-dose vaccines, while J&J is one dose.

2) The lot number and expiration date

The lot number is a string of numbers and letters that tracks this specific batch of vaccine from production into your arm. This lot number is connected to an expiration date, which — much like on any food packaging — indicates when this batch of vaccine may start to degrade. Pfizer and Moderna say their vaccines have a shelf life of up to six months, while Johnson & Johnson says it is conducting ongoing studies to determine how long its vaccine lasts.

This expiration date is not relevant to how long vaccinated people are protected against Covid-19. (That remains unclear.) Instead, the expiration date is primarily helpful for governments and vaccine providers, who have to coordinate buying and using large amounts of vaccine within the limited shelf life.

This is likely to become more important in the coming months as some of the earliest vaccine doses begin to reach their expiration dates. For example, South Sudan announced plans to discard 59,000 doses of donated AstraZeneca vaccine that had expired in April.

3) The date

The date of your shot is important so you know when to return for a second shot, if needed, and when you are “fully vaccinated.” The CDC considers people “fully vaccinated” two weeks after the date of the final shot in the vaccine series.

In addition, the time of your dose may also be included because the CDC advises people to remain under observation of medical professionals for 15 minutes after getting vaccinated, mainly as a precaution in case of a rare allergic reaction.

4) The location

The location of your vaccine dose is written on the vaccination card for reference, just in case the background of your vaccine selfie isn’t clear. In recent weeks, many mass vaccination sites like the Javits Center in New York have begun to wind down operations as demand for the vaccines has lightened.

5) The health care professional

Don’t forget to say thank you!