Currently we have three vaccines available in the US to prevent COVD-19. These include Pfizer, Moderna and as of just recently the Johnson and Johnson vaccines.
More and more people are getting vaccinated and the question now becomes, when can we get back to normal? Are those vaccinated fully immune from COVID-19 and do they still have the potential to spread the virus?
It is important to note that while the vaccines are very effective and are definitely recommended, no vaccine is 100% effective. So this means that even if you have been vaccinated, you can still get the disease, but hopefully the vaccine will prevent you from getting really sick.
The immune system is incredibly complex and there are multiple factors that can lead to vaccine failure. Even if the immune system functions as it is supposed to, there are those who are vaccinated that can still get the disease. From personal experience, I can tell you that I have taken care of two fully vaccinated patients in our COVID ICU recently.
How does this virus get transmitted?
We have learned a lot about this virus over the past year. We know the viral particles can infect another person. But what if you are vaccinated? Can you still transmit the virus even if you don’t get sick?
We know transmission happens when enough viral particles from an infected person get into the body of an uninfected person. So theoretically, anyone who is infected can transmit the disease. This is true even if the person doesn’t get sick. The reason the vaccine is so important is because it can reduce the chance of spreading the virus as well as protection from actually getting sick.
So why all the hype about the vaccines?
The vaccine will reduce the chance of an infection becoming a serious problem that needs inpatient treatment in the hospital. So even if vaccination doesn’t completely prevent infection, it will reduce the chance of shedding the virus and hence decrease the risk of infecting others.
What about the mutant strains?
New variants of coronavirus have emerged in recent months, and recent studies show that vaccines are less effective against certain ones, like the B1351 variant first identified in South Africa. Every time a virus replicates it can produce new mutations and that is how we get mutant strains. The sooner we stop the spread and decrease the cases, the less likely we are going to have new strains that the current vaccine may not be as effective against.
So how does this relate to vaccines and transmission?
For the South Africa variant, vaccines still provide almost 90% protection from getting really sick. But when you count mild and moderate cases, they provide, at best, only about fifty percent protection. That means nearly half of vaccinated people will still get infected and can infect others, even if they don’t get really sick themselves.
If vaccinated people have more virus in their bodies and it takes less of that virus to infect another person, there will be higher probability a vaccinated person could transmit these new strains of the coronavirus.
As more and more people get vaccinated, less and less people should get really sick and even less should succumb to this virus. It is important to note that this vaccine not only reduces disease severity but also can aid in reducing the amount of virus being shed overall.
The emergence of mutants of this virus will mean that even those vaccinated still have the potential to shed and spread the virus to other people, vaccinated or not.
If this happens and spirals out of control, it will mean that reduction in transmission will take longer and hence herd immunity will be delayed. It's hard to predict how this will play out and is highly dependent on how effective these vaccines will be against the “mutant” strains of this virus.
So what should we do in the meantime?
Please remember that medical information provided by us must be considered an educational service only. This blog should not be relied upon as medical judgement and does not replace your physician’s independent judgement. This is NOT medical advice. Please seek the advice of your physician.