D. Clay Ackerly, MD, MSc, an internal medicine and primary care physician practicing in Washington, DC is seeing something that is not good news. Via VOX:
Emerging cases of Covid-19 reinfection suggest herd immunity is wishful thinking.
“Wait. I can catch Covid twice?” my 50-year-old patient asked in disbelief. It was the beginning of July, and he had just tested positive for SARS-CoV-2, the virus that causes Covid-19, for a second time — three months after a previous infection.
While there’s still much we don’t understand about immunity to this new illness, a small but growing number of cases like his suggest the answer is “yes.”
Covid-19 may also be much worse the second time around. During his first infection, my patient experienced a mild cough and sore throat. His second infection, in contrast, was marked by a high fever, shortness of breath, and hypoxia, resulting in multiple trips to the hospital.
Ackerly spells out what may be happening. Some people (long haulers) reportedly can have an infection that lasts weeks or even months. His patient had had two negative PCR tests though, showing the infection had been cleared out. He had been infected a second time through contact with a family member who was positive.
We’ve been dealing with the virus for less than a year now, and there is still a great deal we simply don’t know. It appears some people never really develop immunity after infection and/or the immune response by the body may fade — how quickly we don’t really know. Ackerly reports there are several other people who have been reported as getting sick with Covid-19 a second time. How often this is happening is yet to be determined.
One possibility he doesn’t discuss is that we may not realize this is happening if the first infection is asymptomatic. That means a person getting sick might actually be having a repeat infection, and if his speculation that repeat infections may be worse is correct, that is not good for patient outcomes.
Another matter I have not seen widely discussed is protecting the nation’s blood supply. Given that a still to be determined percentage of the population can be infected but asymptomatic, how many of them are blood donors, and how effectively are blood donations being screened for the virus? During the initial stages of the AIDS crisis, infections via transfusions were one of the ways the HIV virus spread initially. (There’s also the IV drug abuse route, which is still a problem.)
The Red Cross has announced screening procedures, but it’s one more complication in the bigger picture. There’s an urgent need for blood; this would be one way of getting tested for the virus for someone who is otherwise asymptomatic and has not knowingly been exposed. (See the Red Cross link for conditions and disclaimers.)
Ackerly has four takeaways:
- First, the trajectory of a moderate initial infection followed by a severe reinfection suggests that this novel coronavirus might share some tendencies of other viruses such as dengue fever, where you can suffer more severe illness each time you contract the disease.
- Second, despite scientific hopes for either antibody-mediated or cellular immunity, the severity of my patient’s second bout with Covid-19 suggests that such responses may not be as robust as we hope.
- Third, many people may let their guard down after being infected, because they believe they are either immune or incapable of contributing to community spread. As my patient’s case demonstrates, these assumptions risk both their own health and the health of those near them.
- Last, if reinfection is possible on such a short timeline, there are implications for the efficacy and durability of vaccines developed to fight the disease.
CAVEAT: Ackerly acknowledges that this is extrapolating from a very small sample size. We simply do not know with a high degree of confidence how the Covid-19 virus works — we’re on a very steep learning curve, as Ackerly puts it. In a situation that still has a great deal of uncertainty, we can not afford to discount any possibilities out of false hopes.
The apparent success of plasma therapy suggests some people do develop a protective immune response — but again that still has to be confirmed before it can be considered a practical treatment for large scale implementation, especially if immunity does not persist.
There’s also the problem that even if an effective vaccine was available right this instant, there are a number of people who would refuse to take it.
"Most of the arguments the coronavirus deniers use are very similar to those anti-vaxxers have been pushing for decades," Tara C. Smith, professor of epidemiology at Kent State University, said in an op-ed for NBC News. "They suggest that scientists and scientific institutions are hopelessly corrupt, that these institutions and individuals are lying to you and only folks like Mikovits are willing to risk it all to tell you ‘the truth’: that the government and specifically public health institutions should have no influence over how ordinary Americans live their lives and protect themselves and their communities from disease, and that natural immunity to infection is preferable to vaccines.”
There is a lot of demand for positive news about the Covid-19 pandemic for obvious reasons, not least because it has become extremely politicized. Trump’s support is being seriously corroded by his total failure to deal effectively with the pandemic. The administration has gone from touting miracle cures and vaccines “real soon now” to basically trying to ignore it away in hopes people will stop caring about it the way they tolerate inaction on gun deaths. The goal is to normalize millions of people getting sick and thousands dying. The latest Trump move is to start discrediting Dr. Anthony Fauci.
Bottom Line:
Given that we do not have an effective vaccine yet, may not get one, and that immunity against the virus is still largely to be determined, we have only one effective tool against Covid-19: Prevention.
- Wear a medically proven mask or face shield
- Wash hands frequently, use hand sanitizer
- Practice social distancing
- Implement wide scale testing, tracing, and isolation
- Modify the physical environment to combat virus spread. (Air filters, protective barriers, spaced out seating, more cleaning, etc.)
- Develop government policies that make the first three steps practical for individuals
The first three are matters that individuals can practice. The last three depend on having a functioning government with competent leadership….