Covid-19 immunity: ‘Natural immunity’ from Covid-19 infection better than a vaccine?

On the heels of last month’s news of stunning results from Pfizer’s and Moderna’s experimental Covid-19 vaccines, Sen. Rand Paul tweeted a provocative comparison. The new vaccines were 90% and 94.5% effective, Paul said. But "naturally acquired" Covid-19 was even better, at 99.9982%, he claimed.Paul, R-Ky., is one of many people who have extolled the benefits of contracting the coronavirus. The senator was diagnosed with the disease this year and has argued that surviving a bout of Covid-19 confers greater protection and poses fewer risks than getting vaccinated.The trouble with that logic is that it’s difficult to predict who will survive an infection unscathed, said Jennifer Gommerman, an immunologist at the University of Toronto. Given all the unknowns — like a region’s hospital capacity or the strength of a person’s immune response — choosing the disease over the vaccine is “a very bad decision,” she said.The primary advantage of a vaccine is that it’s predictable and safe, she said. “It’s been optimally tailored to generate an effective immune response.”We asked experts to weigh in on some key questions.

Which produces a stronger immune response: a natural infection or a vaccine?

The short answer: We don’t know. But Covid-19 vaccines have predictably prevented illness, and they are a far safer bet, experts said.Vaccines for some pathogens, like pneumococcal bacteria, induce better immunity than the natural infection does. Early evidence suggests that the Covid-19 vaccines may fall into this category. Volunteers who received the Moderna shot had more antibodies in their blood than did people who had been sick with COVID-19.[caption id="attachment_8601401" align="alignnone" width="1280"]

Moderna's COVID-19 vaccine technology could revolutionise future treatments for infectious diseases and pandemics. Image: AP[/caption]

I’m young, healthy and at low risk of Covid-19. Why not take my chances with that rather than get a rushed vaccine?

The experts were unanimous in their answer: Covid-19 is by far the more dangerous option.“It’s clear that one is less problematic for the body to recover from them than the other. There’s more risk with natural infection,” said Marion Pepper, an immunologist at the University of Washington in Seattle.People who are obese or who have diseases like diabetes are particularly susceptible to severe cases of Covid-19. On average, the virus seems to be less risky for younger people, and women tend to fare better than men. But beyond those broad generalizations, doctors don’t know why some people get very sick and die while others have no symptoms.Apoorva Mandavilli. c.2020 The New York Times Company