The last line of the article is the most important:
"If the goal is to prevent infection, then boosting will need to be done after 6 to 18 months depending on the immune status of the individual. If the goal is to prevent serious disease boosting may not be necessary for years."
This is a very important distinction. The media mostly gets this wrong, and CDC has been badly negligent in helping the public understand it.
Vaccines are generally not expected to prevent infection. The only common vaccine that is known to prevent infection is HPV. All other vaccines allow some degree if infection, and thus some continued spread of the target pathogen. Vaccines are designed and tested to prevent serious disease due to infection. That's it.
Likewise, these new vaccines are designed and tested to prevent the disease of covid, not infection by the virus called sars-cov2. The extent to which they do prevent infection, and the resulting effect on R0, is yet to be determined, but it is fully expected that the virus will continue to spread, even as hospitalizations and deaths eventually drop.
To put a finer point on that, there is a difference between infection and disease. You are infected with the sars-cov-2 virus. Which can cause you to contract the disease (covid) if the viral infection gets out of hand.
Getting vaccinated gives your body a headstart in fighting off the virus so that it doesn't become covid. Since you have to become infected before your antibodies go to work, it doesn't totally prevent infection. But it likely keeps the virus tamped down so much so that you are much less likely to spread it. If the virus never really gets to take off, you won't be spreading it to others.
> If the virus never really gets to take off, you won't be spreading it to others.
That might be true for some virii, but unfortunately not for sars-cov2. It became clear early on that asymptomatic and low-symptom infected people can spread the virus. And there's evidence that vaccinated people-- who can still be infected, but are less likely to fall ill-- can spread it as well.
In addition to differences in length of time and site of the exposure between mRNA vaccine and natural infection, could it also be that natural infection triggers antibodies and memory to more than one of the 29 proteins the virus has - vs only the spike protein that mRNA vaccines produce? This might also make natural infection be able to deal with variants better in the future.
What I’m really curious about is will vaccine + natural infection give you a long lasting strong immunity - it seems natural infection first and vaccine after does according to some studies I’ve seen, but of course that’s risky. Unclear how well it works in reverse order.
I think in the end we will all get infected over the coming year or three as protection from the vaccine wanes and we have repeated exposure due to multiple waves and increased social mixing, but the vaccination should significantly reduce incidence of serious illness and long COVID. After having both the vaccine and (I think unavoidable) natural infection hopefully we should have a long lasting strong immunity which will keep future waves at bay. This happened naturally with Spanish flu over 2 years, but it decimated 1-4% of the global population in the process due to not having vaccines or therapeutics.
> I think in the end we will all get infected over the coming year or three as protection from the vaccine wanes and we have repeated exposure due to multiple waves and increased social mixing, but the vaccination should significantly reduce incidence of serious illness and long COVID. After having both the vaccine and (I think unavoidable) natural infection hopefully we should have a long lasting strong immunity which will keep future waves at bay. This happened naturally with Spanish flu over 2 years, but it decimated 1-4% of the global population in the process due to not having vaccines or therapeutics.
We're already close to 2 years with SARS-CoV-2 and the experts are talking about new variants, not the end of the pandemic.
While I am vaccinated and think it's clear that the vaccines are effective at reducing the incidence of serious illness and death, my concern is that by vaccinating into a pandemic, we have created selective pressures we can't predict the consequences of.
There could also be other unintended consequences. As you noted, it seems natural infection followed by vaccination results in lasting immunity, but what if vaccination before natural infection has the effect of limiting the immune system's ability to develop broad T-cell immunity? If this turns out to be the case, all of us vaccinated people might actually be delaying the end of the worst of the pandemic.
Yes exactly. There could still be some nasty surprises in store with more dangerous variants (higher death rate, affects children etc - I really hope not). We will know soon. There are now populations that Delta has ravaged with and without vaccines so we should be able to do comparative studies and tell the difference soon with regards to immunity response between the two against new variants should one start spreading.
The 2 year thing - the world is different than in 1918 and the virus is different so it might not go exactly the same way. But I’m hoping natural immunity and infection together will stamp it out soon. Would suck if the people who were vaccinated first will never be able to form broad long lasting immunity, or if vaccination has the effect of creating selective pressures of changing just the spike protein in some nasty way, which wouldn’t have necessarily happened if we had natural broader immunity.
I am also vaccinated for the record, and amazed at the technical feat and future potential of mRNA vaccines. But evolution and immune systems are complex things.
This was also my understanding of the natural antibody response: that it can identify more than just a single protein and creates antibodies to multiple features of the virus. This can be expected to provide broader protection.
"If the goal is to prevent infection, then boosting will need to be done after 6 to 18 months depending on the immune status of the individual. If the goal is to prevent serious disease boosting may not be necessary for years."
This is a very important distinction. The media mostly gets this wrong, and CDC has been badly negligent in helping the public understand it.
Vaccines are generally not expected to prevent infection. The only common vaccine that is known to prevent infection is HPV. All other vaccines allow some degree if infection, and thus some continued spread of the target pathogen. Vaccines are designed and tested to prevent serious disease due to infection. That's it.
Likewise, these new vaccines are designed and tested to prevent the disease of covid, not infection by the virus called sars-cov2. The extent to which they do prevent infection, and the resulting effect on R0, is yet to be determined, but it is fully expected that the virus will continue to spread, even as hospitalizations and deaths eventually drop.