The cost-effectiveness of vaccinating pregnant or lactating women against SARS-CoV-2 - Part 3
“The Conversation” piece
We now come to the criticism by two academics in the Conversation, an outlet that has always consistently reflected the prevailing narrative.
The authors are concerned by the proposed withdrawal of Covid vaccination to pregnant women from the spring of 2025 for several reasons:
Pregnant women are at higher risk of Covid infection.
Their evidence for this is a nonsystematic review by Gao et al., which lists “physiological changes” in pregnancy in the first trimester as making them more susceptible to Covid. In turn, Gao et al. cite a 2020 US CDC paper by Ellington et al.
Ellington et al. report surveillance on 325,335 women aged 15-44 who tested positive for SARS-CoV-2, 28% of whom had data on pregnancy status, and 9% were pregnant.
No information on viral load is reported, and much is made of the severity of the disease: “Hospitalization was reported by a substantially higher percentage of pregnant women (31.5%) than nonpregnant women (5.8%) (Table 2). Data were not available to distinguish hospitalization for COVID-19–related circumstances (e.g., worsening respiratory status) from hospital admission for pregnancy-related treatment or procedures (e.g., delivery)” (our emphasis). So these pregnant women could have been admitted for, say, a breech presentation or signs of foetal anoxia or pre-eclampsia. With such a potentially highly biased sub-sample, it is impossible to draw conclusions.
The risk of Covid infection can be reduced by vaccination.
This statement is based on a UK cohort study of 3,699 pregnant women admitted to hospital with SARS-CoV-2 by symptom group between 15 December 2021 and 14 March 2022. Again, no details are given about the likelihood of these women being infectious. Still, the authors compare the pregnant women by the presence and severity of symptoms with a list of sociodemographic variables, including one or more exposures to the vaccines (Table 1).
Only once you get to the bottom of the table can you calculate the missing data. Immunisation status was “not known or not documented” in 635/1886 women (34%). To keep it brief, the authors in the end state, “Our results indicate that most current instances of respiratory failure among pregnant women are preventable, yet vaccine uptake among pregnant women remains low compared with the general female population of reproductive age.” In other words, pregnant women were reluctant to be vaccinated, introducing a healthy vaccinee bias. This selected subset of vaccinated is highly unlikely to be comparable to the non-vaccinated set. Such is the reality when you are dealing with observational studies.
Indirect benefit to the newborn from the mother’s vaccination.
This argument is based on the protective effect of mum’s vaccine-generated antibodies in the first 6 months of life. This is supported by a CDC presentation that does not mention the function of maternal antibodies. The CDC presentation does mention absolute vaccine effectiveness but warns about the likely bias in the estimates. We are not sure what function presenting knowingly biased estimates has.
Throughout the Conversation piece, the authors are at pains to present the message of how desperately vulnerable newborns can be to SARS-CoV-2. That may be the case (as they are vulnerable to all agents). Without randomised trial evidence, we cannot know whether newborns can be protected directly or indirectly by vaccination.
However, there is one thing we agree with the authors of the Conversation piece.
The JCVI’s assessment of the cost-effectiveness that led to the change in recommendation to withdraw the COVID vaccine in pregnancy is unclear. We are unlikely ever to understand the economic alchemy, given that the data aren’t available and the assumptions that form the modelled estimates remain unclear.
Finally, the potential harms of any of the alternatives are never mentioned in any of the documents we examined, which is odd, given that one of the vaccines has already been withdrawn due to toxicity.
So, to sum up the series of three posts: the absence of visible clinical trial data on the effects of the different SARS-CoV-2 vaccines in pregnant women favours poor science, unclear decisions, and ideological stances.
Two old geezers who enjoyed writing the short series wrote this post.
Readings
Risk factors for severe and critically ill COVID-19 patients: A review. Allergy. 2021 Feb;76(2):428-455. doi: 10.1111/all.14657.
Characteristics of women of reproductive age with laboratory-confirmed SARS-CoV-2 infection by pregnancy status - United States, January 22-June 7, 2020. MMWR Morb Mortal Wkly Rep. 2020;69(25):769-775.
Severity of maternal SARS-CoV-2 infection and perinatal outcomes of women admitted to hospital during the omicron variant dominant period using UK Obstetric Surveillance System data: prospective, national cohort study: BMJ Medicine 2022;1:e000190.
Epidemiology of COVID-19-Associated Hospitalizations, including in Pregnant Persons and Infants. Advisory Committee on Immunization Practices. June 23, 2023. CDC
Vivien, you last line is the punch line. Promoting experimental vaccines without evidence.
Best wishes, Tom
This here old geezerette thanks you old geezers for this miniseries because it documents excellently how common sense and, worse, previous advice, has been dumped at the door: ideology ("we must do something, now, or we're all gonna die of covid") reigns supreme.
The two main points standing out for me are:
@1: the general caution promoted to women of childbearing age, to be found on any medicine or supplement, i.e. to avoid taking it if pregnant when in doubt, has been completely trashed in order to promote yon vaccine. I wonder when someone collects all those 'anecdotes' about all those babies having been still-born after the woman had that vaccine ... am not holding my breath ...
@2: look at this glaring idiocy shown in the quote from the paper by Mr Gao: "“physiological changes” in pregnancy in the first trimester as making them more susceptible to Covid.". If that were the case, then shouldn't there have been over the decades, data on pregnant women being more susceptible to ILI? More sweepingly, wouldn't;t humanity have had no chance to develop if pregnancy meant being more susceptible to ILI and bacterial infections following ILI, at a time when there were no drugs and actually no medical doctors as we know them today?
It's a miracle, innit like, that humanity has actually made it to the present day when 'advice by experts', from weather to health, was nonexistent for millennia ...