Public Acceptance of COVID-19 Vaccine Faces Many Hurdles
Published August 25, 2020 | Vaccination, Future Vaccines
Story Highlights
- Even before a vaccine against COVID-19 has been introduced to the public in the U.S., expectations for it are low.
- Dr. Anthony Fauci warns that a COVID-19 vaccine is not expected to be either long-lasting or more than 50 to 60 percent effective.
- Citing experience with other vaccines, a COVID-19 vaccine is not expected to provide much, if any, benefit for obese patients, defined as those with a greater than 30 percent body mass index (BMI), which includes approximately 42 percent of adults in the U.S.
has said chances are slim that early vaccines against COVID-19 will be “highly effective,” defined as having a 98 percent effectiveness rating.1 Instead, Fauci predicts that an effectiveness of 60 percent or less is about the best that might be expected, adding that a vaccine with even 50 percent effectiveness would probably be considered acceptable and given the “green light” by the FDA.2
Fauci has also said that, if COVID-19 acts like other coronaviruses, vaccination may not provide durable protection. In a live stream videoconference, he said: “You can assume, that you’re going to get protection at least to take us through this cycle. When you look at natural infection it’s anywhere from six months to a year. However, with this spike protein that’s being presented in the way that we do it, with primes and in some cases boosts, we’re going to assume that there’s a degree of protection, but we have to assume that it’s going to be finite.”3
Low Expectations for Early COVID-19 Vaccines
Adults and people with co-existing chronic conditions, such as diabetes or heart disease, as well as those who are obese or live with chronic stress, are recognized as being at higher risk for complications from SARS-Cov-2 infections. Many of these same chronic poor health conditions also are predictive of adverse responses to vaccines in general. Older age, for example, is known to be associated with a less robust immune response to both vaccination and natural infection.4 Gender, genetics, blood type and underlying conditions such as diabetes mellitus, all of which have been associated with more severe COVID-19 infection outcomes, have been found to influence individual immune responses to certain vaccines, although significant variations are reported.5COVID-19 vaccines are not expected to provide much, if any, benefit for the more than 107 million people in the U.S. classified as obese.6 It has previously been recognized that vaccines are not as effective in obese people compared to the general public.7 According to Raz Shaikh, associate professor of nutrition at the University of North Carolina-Chapel Hill, there is no reason to think a COVID-19 vaccine will be any different. He said: “Will we have a COVID vaccine next year tailored to the obese? No way… Will it still work in the obese? Our prediction is no.”8
The Role of Obesity in Vaccine Responses
Early warnings about the increased COVID-19 infection risks faced by the obese in the pandemic came from China, where it was reported that patients with a higher body mass index (BMI) were significantly more likely to become critically ill or die from their illness compared with the general patient population.9 The first reports from the Centers for Disease Control and Prevention (CDC) indicated that patients considered “morbidly obese,” defined as those with a BMI of 40 or more, or 100 pounds over recommended weight, were at highest risk for developing severe coronavirus symptoms.About nine percent of the U.S. population falls into the morbidly obese category. As the picture of which patients were most severely affected by COVID-19 became clearer, however, the warning has been expanded to include those at a BMI of 30 and above, or 42.4 percent of adults in the U.S.
Researchers are not sure why obesity seems to have such an impact on immune response and response to vaccination but mechanisms involving chronic inflammation may be responsible. Inflammation is a normal response to infection (or vaccination). After the immune system’s inflammatory response to the perceived threat posed by infection or vaccination is mounted, normally the inflammation ceases and health returns. However, in obese people and those with related risk factors, such as high blood pressure or elevated blood sugar levels, the inflammatory response does not “turn off” and progresses to a state of chronic mild inflammation.10
Others have suggested that the standard 1” needle may not be adequate to reach muscle tissue. It has been speculated that those with a higher BMI may require larger doses of vaccine product.11
Hepatitis B and Influenza Vaccines and Obesity
Early evidence of the effect of obesity on response to vaccination was reported in a 1985 study of hundreds of hospital workers vaccinated against hepatitis B. In that study, the hepatitis B vaccine was half as likely to protect against hepatitis B in those with a higher BMI compared to their co-workers with lower BMIs. Even when the trial was repeated with longer needles to ensure the vaccine was injected into muscle tissue rather than adipose tissue (fat), the results were the same.A 2017 study showing that even though obese patients vaccinated against influenza did produce “a protective level of antibodies to the influenza vaccine,” they were still twice as likely as non-obese adults of a healthy weight to develop influenza or flu-like illness, at 9.8 and 5.1 percent, respectively. Those authors concluded that, “the current standard for correlates of protection, suggesting use of antibody titers to determine vaccine effectiveness in an obese population may provide misleading information.”12
Obese patients have commonly been excluded from clinical trials on experimental drugs and vaccines due to concerns that co-morbidities frequently associated with obesity might cloud results. COVID-19 safety and efficacy trials currently underway do not exclude people with obesity. Although obesity is not being viewed as a specific potential complication at this point, BMI for study participants will be reported and evaluated.13
Rapid COVID-19 Vaccine Approval Sparks Concerns
With a stated goal of delivering “300 million doses of a safe, effective vaccine for COVID-19 by January 2021, as part of a broader strategy to accelerate the development, manufacturing, and distribution of COVID-19 vaccines, therapeutics, and diagnostics (collectively known as countermeasures),” operation “Warp Speed” has already streamlined procedures ordinarily in place to test the safety and efficacy of vaccines over the course of years.14 The Warp Speed plan states that no corners will be cut that would compromise the safety of the proposed vaccines, even though clinical trial steps are being taken simultaneously rather than consecutively as is done in non-emergency circumstances.For example, the most promising vaccine candidates are being manufactured “at industrial scale” even before the studies are completed to establish vaccine efficacy and safety as happens normally. Theoretically, this strategy supposedly increases financial risk for companies but does not increase product risks.
Francis Collins, MD of the National Institutes of Health (NIH) has said:
I think this is an effort to try to achieve efficiencies, but not to sacrifice rigor… Definitely the worst thing that could happen is if we rush through a vaccine that turns out to have significant side effects [The NIH] is creating a master plan for testing the leading COVID-19 vaccine candidates in tens of thousands of people, to prove whether they really work and if they’re safe.Addressing Russia’s newly approved vaccine, “Sputnik V,” scientists and public health professionals have expressed concern that the Russian vaccine still needs critical safety and efficacy studies, and they worry that the hasty introduction of that vaccine could put pressure on the U.S. to prematurely approve a COVID-19 vaccine of its own.15
Only about half of Americans plan to get the COVID-19 vaccine if it becomes available, with 7 in 10 of those who plan to refuse citing concerns about safety issues surrounding the rushed approval process to fast track a vaccine to licensure.16
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