Wednesday, Mar 29, 2023

Do Pfizer’s Trial Results Justify Covid-19 Jabs For Kids?

Do Pfizer’s Trial Results Justify Covid-19 Jabs For Kids?

Did Pfizer’s trial in kids detect a Covid-19 problem to claim a solution? What about the long-term effects of vaccines?

Representative image. AP

Historically, vaccines have saved many kids’ lives against deadly diseases. Do the current Covid jabs for kids fall in the same category? While several epidemiologists and doctors have said that Covid jabs for kids are unnecessary, some have opined that it could have benefit. On 29 Oct 2021, the FDA (USA) approved the emergency use of Pfizer’s mRNA jab for use in kids aged 5-11, while a similar jab has been approved for kids aged 12+ since 10 May 2021. What do Pfizer’s own trial results on kids show? Do they indicate a medical benefit of Covid vaccination for kids? What are the implications of these for India? Let us take a closer look.

Undetected problem, unproven “solution”: The primary reason to vaccinate kids should be in terms of a clear medical benefit to them. Was this shown in Pfizer’s trials? The way typical vaccine trials are conducted is that there is a group of participants (kids in this case) who are vaccinated, and a control group which is injected with a placebo. And the outcomes are compared across the two groups. In Pfizer’s kids’ trial, there were 1518 kids in the vaccine group, and 750 in the control group. Can you guess how many kids were saved from hospitalization? It was zero. What about severe Covid outcomes? What about MIS-C (Multisystem Inflammatory Syndrome in Children)? These too were zero in both groups: there were “no cases of severe COVID-19 and no cases of MIS-C” (page 10); (Of course, there were no fatal outcomes either, in either group). If the trial did not even detect a single “severe Covid” or “MIS-C” problem even in the placebo group, how can it claim a solution to the same using the jab?

Flaws in the ostensible reason: So why was emergency use of the jab approved by FDA (USA) for kids? The ostensible reason is the claim of 90% efficacy in preventing Covid and a projected reduction in kids’ hospitalization. These claims are flawed on multiple counts.

(1) As shown in Table 13 (page 61) of the document, the risk of testing PCR+ve is actually reduced from 2.51% in the placebo group, to about 0.24% in the vaccine group. Therefore the 90% risk reduction claim is misleading as it is relative; the absolute risk reduction is a mere 2.27%. In plain terms, given that even the not-severe (mild) Covid is rare in kids, the absolute risk reduction has to be negligible.

(2) Next, as the experience with the adults’ vaccine has shown, vaccine efficacy wanes with time: this is why we are seeing vaccine breakthrough infections everywhere. So how long will the above 2.27% risk reduction last?

(3) Now, even this 2.27% risk reduction is in terms of PCR positive test results. It is important to remember that a PCR+ve does not mean illness; it need not even mean presence of live virus. Indeed, the UK government’s guidelines on Covid-19 management for healthcare staff (Jan 2021) says “fragments of inactive virus can be persistently detected... long after a person... is no longer infectious”; this can be for as long as 90 days! By now, we all likely know of several people in our circles who test PCR+ve but are not ill. This being the case for adults, it is all the more so for kids.

(4) In the context of India, sero-surveys show that by now at least 75% of kids have already been naturally exposed to the virus (despite hugely damaging school closures) without us even noticing it, and now have even more robust natural immunity against severe Covid.

(5) Last but not least, what really matters is not so much the reduction of mild symptoms, but whether severe disease outcomes are lessened; but as explained earlier, there were no severe Covid outcomes in kids in the trial, to reduce. That is, the absolute risk reduction in severe Covid due to the jab, as per Pfizer’s own trial data, is not 90%, not even 2.27%, it is zero!

Pfizer’s report computes the number of kids saved from Covid hospitalization (page 11), by taking the US-wide prevalence of such hospitalization over the entire pandemic, and erroneously applying the 90% mild-Covid efficacy number for hospitalizations too. The projected computation also does not account for the fact that many kids are now already exposed. Yet another flaw in the projection is that many kids may be testing PCR+ve in hospital after being admitted for a non-Covid reason; studies have shown such over-count of Covid-labeled hospitalization even among adults.

Short-term, long-term risks: Alongside the flawed claims of risk reduction, juxtapose the fact that in Pfizer’s own trial data, there were six reports of severe adverse events in the vaccine group, and none in the placebo group (Table 5). Of these six, one was concerning enough for the participant to withdraw from the trial. This is especially significant, since many countries have withdrawn various Covid vaccines for younger age-groups (e.g. Moderna withdrawn for ages 18-24 in Canada), as risks became clear with time.

What about long-term effects? Since it has not been a long time since the trial, it is impossible to know what the long term holds. Pfizer’s report promises “5 post-authorization safety studies, including a 5-year follow-up” to study possible long-term effects (page 11).

Similar results in 12-25 age-group: Pfizer conducted a separate trial in the 12-25 age-group who results are similar; the result clearly says “No cases of severe Covid-19” in the 12-15 age group (page 7); no severe Covid cases were reported in the 16-25 age group too. And in this trial too, the instances of severe adverse events are 3 to 3.5 times more in the vaccine group, compared to the placebo group (Table S2).

Implications for India: While Pfizer’s trials involved about 2250 kids, the trial sizes for India’s kids vaccines are even smaller (525: Covaxin, 1000: ZyCoV-D), and hence even more problematic. Such small trial sizes cannot detect the rare cases of severe Covid in kids, nor detect anything but the most obvious side-effects. The unknown nature of long-term risks would apply for India’s trials too. While a kids vaccine with a clearly demonstrated medical benefit after considering risk-reward ratio would be quite welcome, for the current Covid jabs, we really have to ask: what is the need for an irreversible medical intervention in terms of an unproven jab, when most Indian kids’ immune system has already fought off the virus without us even noticing it, when there are unknown long-term risks of the jab?

(Bhaskaran Raman and Om Damani are faculty in the Department of Computer Science and Engineering at IIT Bombay. Views are personal.)