Side Effects: Why Those Who Have Been Vaccinated Get Coronavirus

Side Effects: Why Those Who Have Been Vaccinated Get Coronavirus
Side Effects: Why Those Who Have Been Vaccinated Get Coronavirus

Video: Side Effects: Why Those Who Have Been Vaccinated Get Coronavirus

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In Russia, mass vaccination will begin on December 10, in any case, the Minister of Health Murashko said that Sputnik V has arrived in all regions of the country. Prior to that, Moscow and Moscow region, Novosibirsk region received the vaccine. The first, on whom the drug is tested, were teachers and doctors, allegedly on a voluntary basis, but as it often happens in our country - on a voluntary-compulsory basis. Vaccination takes place in a pandemic, when you have to choose between two evils - the risk of getting sick and vaccination with drugs that have not undergone a full study. We already know about cases of illness after vaccinations. This is also being discussed abroad.


In the US, all eyes are on Pfizer and Moderna. At first glance, the results of experimental trials of a COVID-19 vaccine are striking in their effectiveness. Pfizer says it has reported 170 cases of COVID-19 (out of 44,000 volunteers), with a wide range of 162 cases in the placebo group and 8 cases in the vaccine group. Meanwhile, Modern reports that 95 of the 30,000 volunteers participating in the ongoing trial contracted COVID-19: 90 while receiving a placebo, compared with 5 receiving the vaccine. As a result, both companies claim about 95% efficiency.

Let's put this in perspective. First, a relative risk reduction is reported, not an absolute one. Which is less than 1%. Second, these results relate to the primary endpoint of COVID-19 trials of almost any severity and, importantly, not the vaccine's ability to save lives, its ability to prevent infection, or its effectiveness in important subgroups (for example, the elderly with impaired health). … These parameters are still unknown. Third, these results reflect a point in time relatively soon after vaccination, but we know nothing about the effectiveness of the vaccine after 3, 6 or 12 months. Therefore, we cannot compare these efficacy rates with other vaccines such as influenza vaccines (which are assessed on a seasonal basis). Fourth, children, adolescents, and immunocompromised people were largely excluded from the trials), so we still lack any data on these important populations.

Earlier, I argued that trials are looking at the wrong endpoint, and there is an urgent need to adjust course and explore more important endpoints, such as preventing severe illness and transmission in high-risk people. However, while regulatory mechanisms are in place to ensure access to the vaccine while maintaining a high approval level (which would allow placebo-controlled trials to continue long enough to answer this important question), it is difficult to avoid the impression that sponsors are claiming victory and ending their tests. (Pfizer has already sent out a letter to trial participants discussing the "switch" from a placebo to a vaccine). And now the FDA will be under tremendous pressure to quickly approve these vaccines.

But when the conversation turns to vaccine distribution, let's not lose sight of the evidence. Independent validation of key test data will increase confidence in the results. In addition, there may be important limitations to the study results that we need to be aware of.

More importantly, we need evidence-based assurance that the studies were not inadvertently "non-blind," that is, researchers or volunteers could make reasonable assumptions about which group they were in.Blindness is most important when measuring subjective endpoints - such as symptomatic COVID-19 - and differences in side effects after vaccine and placebo injections would perhaps allow some educated guesswork. Past placebo-controlled influenza vaccine trials have failed to fully cover up vaccine status, and the recent 'half-dose' failure in the Oxford covid-19 trial appears to have been seen (only due to milder-than-expected side effects (And this is just one of the many problems associated with the Oxford trials.)

Unlike placebo with saline, early research has shown that systemic and local side effects are common in those receiving the vaccine. For example, in one Pfizer trial, more than half of the vaccinated participants experienced headaches, muscle pain, and chills, but the early trials were small and highly biased. To date, few details have been published from large Phase 3 studies. Modern press release states that 9% have experienced Grade 3 myalgia and 10% experienced Grade 3 fatigue; According to Pfizer, 3.8% experienced grade 3 fatigue and 2% experienced grade 3 headache. Grade 3 adverse events are considered serious and are defined as interfering with daily activities. Mild to moderate reactions are much more common.

One way that raw research data could facilitate making an informed judgment about whether any potential disclosures could have influenced the results is by analyzing how often people with COVID-19 symptoms were referred for confirmatory testing for SARS. -CoV-2. Without referral for testing, a suspected case of COVID-19 cannot become a confirmed case of COVID-19, and thus is an important step to count as a primary event - a laboratory-confirmed, symptomatic COVID-19 case. Since some of the adverse reactions to the vaccine are themselves also symptoms of COVID-19 (eg, fever, muscle aches), a much larger proportion of people who receive the vaccine can be expected to have swabs and be tested for SARS-CoV-2 than those who took a placebo.

This suggests that, as you would expect, all people with symptoms will be tested. However, Modern and Pfizer's test reports are clear-cut language instructing researchers to use their clinical judgment to decide whether to send people for testing.

This is tantamount to asking researchers to guess which intervention group the patients were in. But when illness and vaccine side effects are the same, how can a doctor judge the cause without a test?

Importantly, corporate guidelines only apply to the first seven days post-vaccination, leaving it unclear what role clinical judgment can play on key post-vaccination days when COVID-19 cases may escalate towards the primary endpoint. (for Pfizer - 7 days after the second dose; for Modern - 14 days)

A proper trial must record all cases of COVID-19 - no matter where in the study a particular case was reported (from an epidemiological point of view, there should be no validation bias or differential measurement error). In the era of COVID, it has even become common sense: “test, test, test”. But unless all people with COVID-19 symptoms are referred for testing - for example, because it was assumed that the symptoms were caused by side effects of the vaccine - specific cases may not be considered.

The data on pain relievers and antipyretic drugs are also noteworthy. Symptoms caused by a SARS-CoV-2 infection (such as fever or body aches) can be controlled with pain relievers and antipyretic medications.If people in the “vaccine group” took such prophylactic drugs more often or for a longer period of time than in the “placebo group,” this could lead to better suppression of COVID-19 symptoms after SARS-CoV-2 infection in The "vaccine group", which reduces the likelihood of suspecting COVID-19, reduces the likelihood of testing, and therefore reduces the likelihood of reaching the primary endpoint. But in such a scenario, the effect would be due to the drugs, not the vaccine.

Neither Moderna nor Pfizer provided any samples of written materials handed to patients. Therefore, it is unclear what instructions were given to patients regarding the use of drugs to treat side effects after vaccination, and whether such materials were available. But Johnson and Johnson's informed consent form for the vaccine trial recommends: “Following the introduction of Ad26.COV2.S, fever, muscle aches and headaches appear to be more common in young adults and can be serious. For this reason, we recommend that you take antipyretic or pain relievers if symptoms appear after vaccination, or as recommended by your research doctor."

Announcing “95% efficiency” can be much more complicated than meets the eye. Or maybe not. Only complete transparency and thorough background checks will allow you to make informed decisions. The data must be published.

Posted by Peter Doshi - Deputy Editor of The BMJ Medical Journal.

Translated by Sergei Dukhanov.

Source: The BMJ

Copyright Dr. Peter Doshi, The BMJ, 2020

Published with permission of the publisher (

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