We know that the currently approved COVID-19 vaccines are very effective at preventing you from getting sick, but will they also keep you from getting infected with SARS-CoV-2 and being contagious to others?
Many of you are likely thinking, wait, what, that’s a thing after you get vaccinated?
Will COVID-19 Vaccines Prevent the Spread of SARS-CoV-2 Infections?
To begin to understand this issue, you first have to know that although many people use the two terms interchangeably, there is a difference between infections and disease.
“Infection does not necessarily lead to disease. Infection occurs when viruses, bacteria, or other microbes enter your body and begin to multiply. Disease, which typically happens in a small proportion of infected people, occurs when the cells in your body are damaged as a result of infection, and signs and symptoms of an illness appear.What You Need to Know About Infectious Disease.
In general, when you have an infection, the viruses, bacteria, or parasites, etc., can be inside and growing somewhere on or in your body, but they are not necessarily causing any symptoms.
Are you contagious when you have these types of asymptomatic infections? Sometimes.
Do vaccines prevent infections? Most of the time.
“…we do not yet know if a vaccinated person who encounters the virus can still experience what is referred to as “asymptomatic infection.” An asymptomatic infection occurs when a person is exposed to the virus in the community and the virus can still replicate in their body, but they don’t have symptoms because their immune system stifles the infection as a result of vaccination. In this scenario, the person could potentially spread the virus without even knowing they are infected.”Questions and Answers about COVID-19 Vaccines
Will the COVID-19 vaccine prevent disease and infections? We don’t know yet.
“Challenge studies in vaccinated primates showed reductions in pathology, symptoms, and viral load in the lower respiratory tract, but failed to elicit sterilising immunity in the upper airways. Sterilising immunity in the upper airways has been claimed for one vaccine, but peer-reviewed publication of these data are awaited.”What can we expect from first-generation COVID-19 vaccines?
Except for the Novavax COVID-19 vaccine, these vaccines didn’t prevent infection in primate studies, although they did prevent disease.
“Current COVID-19 vaccine candidates are administered by injection and designed to produce an IgG response, preventing viremia and the COVID-19 syndrome. However, systemic respiratory vaccines generally provide limited protection against viral replication and shedding within the airway, as this requires a local mucosal secretory IgA response. Indeed, preclinical studies of adenovirus and mRNA candidate vaccines demonstrated persistent virus in nasal swabs despite preventing COVID-19.”COVID-19 Vaccines May Not Prevent Nasal SARS-CoV-2 Infection and Asymptomatic Transmission
Unfortunately, we don’t even know if folks who get COVID-19 naturally might be able to get reinfected and be contagious to others, even though they are likely protected from getting sick again for some time.
“People who have previously been infected with covid-19 are likely to be protected against reinfection for several months, but could still carry the virus in their nose and throat and transmit it to others, according to a study which regularly tested thousands of healthcare workers.”Covid-19: Past infection provides 83% protection for five months but may not stop transmission, study finds
And that’s why everyone will need to wear a mask and practice social distancing, both those who have been vaccinated and those who have had COVID-19 until they have been vaccinated.
At least we will until the pandemic is well controlled.
More on COVID-19 Vaccines
- Which Vaccines Don’t Prevent the Spread of a Disease?
- Should I Stop Calling Chickenpox and Measles Diseases?
- Do Vaccines Prevent Disease or Infection?
- COVID-19 Vaccination Questions and Answers
- How Long Does It Take for the COVID-19 Vaccines to Work?
- We Know Vaccines Work
- Challenging the Concept of Herd Immunity
- Mask Exemptions for Kids During the COVID-19 Pandemic
- What You Need to Know About Infectious Disease
- Questions and Answers about COVID-19 Vaccines
- COVID-19 Vaccines May Not Prevent Nasal SARS-CoV-2 Infection and Asymptomatic Transmission
- What can we expect from first-generation COVID-19 vaccines?
- Principles of Epidemiology in Public Health Practice, Third Edition An Introduction to Applied Epidemiology and Biostatistics
- Covid-19: Past infection provides 83% protection for five months but may not stop transmission, study finds
- Single-dose intranasal administration of AdCOVID elicits systemic and mucosal immunity against SARS-CoV-2 in mice
- Prospects for mucosal vaccine: shutting the door on SARS-CoV-2
- Endemic SARS-CoV-2 will maintain post-pandemic immunity