Viewpoint: Monitoring Systems Track COVID Vaccine Reactions

December 15, 2020
Kevin Kavanagh, MD

V-Safe and VAERS are 2 monitoring systems for patients who are given a COVID-19 vaccine. Infection preventionists can play a vital role in educating about the strengths and drawbacks of each.

The vaccines are finally here, no less than a modern scientific miracle. But much still needs to be done, since vaccines do not prevent disease, vaccinations do and infection preventionists (IPs) will play a central role in vaccine administration.

The Pfizer/BioNTech mRNA vaccine for coronavirus disease 2019 (COVID-19) (and hopefully soon to follow the Moderna mRNA vaccine) has received emergency use authorization (EUA) from the US Food and Drug Administration. It is important to remember that authorization for use is not approval for use.

This is an important distinction, since Phase III data for these vaccines have only covered approximately 2 to 3 months post vaccination, and not the usual 6 months to 1 year. The trials are large, approximately 30,000 individuals, and most severe complications occur within the first 2 months after vaccination.

However, questions remain. We do not know how long immunity will last, if those vaccinated can become infectious as an asymptomatic carrier, or how the vaccine affects special populations such as those who are pregnant, very young or immunosuppressed. Thus, all who have received a vaccine still need to follow all of the recommendations by the US Centers for Disease Control and Prevention (CDC) regarding prevention of transmission, including masking, social distancing in public and the donning of personal protective equipment (PPE) in the workplace.

In addition, long-term complications such as vaccine-enhanced disease are a rare possibility. It should be noted that the very specific immunological response elicited by the mRNA vaccines is expected to make this complication even rarer.

Patient monitoring is also of utmost importance both for delayed and rare complications. There are two systems which IPs need to become familiar with. This first is VAERS, Vaccine Adverse Event Reporting System. This system is passive and designed for the reporting of severe vaccine reactions. VAERS can rapidly detect adverse events and detect rare events, but is not designed to determine causality. Often the available information is of inconsistent quality and completeness. Healthcare personnel must report an event to VAERS if there is a vaccine administration error, serious adverse event, the occurrence of multisystem inflammatory disease, or a hospitalization or death. The reporting website along with instructions can be found at

The second reporting system is V-Safe. It is an active reporting system in which patient participation needs to be encouraged. IPs can play a vital role in both patient enrollment and education. A provider tool kit is available from the CDC and a patient information sheet can be downloaded from: There is both a QR Code and a web link ( ) for enrollment.

V-safe is a smart phone system. Any phone which has a browser and is capable of receiving texts can enroll and link a patient to this important monitoring system. Patients will be sent texts every day for the first week, then once a week for 6 weeks, and then at 3, 6 and 12 month intervals. If a second vaccine dose is received, the timeline resets. During the first week, the patients are asked questions regarding common vaccination symptoms such as fever, injection site discomfort, body aches and fatigue. However, during all contacts three questions are asked:

  • Did you miss work?
  • Are you unable to do normal daily activities?
  • Did you receive medical care?

It the answers to any of these is “yes” the patient will be contacted by the CDC and additional information will be taken. A VAERS report will also be made. It should be noted that patient participation in V-Safe does not relieve the healthcare provider of the responsibility of reporting adverse events to VAERS.

For healthcare providers, there are several other considerations regarding vaccination. Because missing work for 1 to 2 days post vaccination is not uncommon, it may be best to stagger vaccinations among co-workers. In addition, if someone becomes symptomatic 3 days after vaccine administration, CDC guidance should be followed on how to differentiate this occurrence from a SARS-CoV-2 infection. In general, post vaccination symptoms may include: Fever, fatigue, headache, chills, myalgias and arthralgia. They can be mild to moderate in severity and occur within the first 3 days of vaccinations, usually resolving one to two days after onset. Symptoms of sore throat, cough, shortness of breath, or loss of taste and smell are not those associated with vaccinations. Finally, mRNA vaccines do not affect antigen or PCR COVID-19 tests. Thus, testing will play a role in differentiating post vaccination symptoms from COVID-19.

It should be apparent that IPs need to become very familiar with the current CDC guidance and any updates which will eventually ensue as more vaccines are released and more data becomes available. This is an exciting time for IPs, a time where their training and expertise will be put to the test and where a profound real-world impact will be made.