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Scientists comment on the upcoming ACIP (Advisory Committee on Immunization Practices) meeting where CDC vaccine advisers will discuss COVID-19, MMRV and Hep B vaccine recommendations.
Responding to the question on evidence to suggest that either pregnant women or children are at risk from taking the covid vaccine, and recent reports that the Trump health officials plan to link coronavirus vaccines to the deaths of 25 children:
Prof Adam Finn, Professor of Paediatrics, University of Bristol, said:
“There is a well-established list of both mild and more serious side effects – which are distinct for the different vaccines.
“I’m not aware of any additional or different known problems specific to children or pregnant women – the ones one would be most concerned about in the latter group are pregnancy loss and/or fetal injury/malformation or other pregnancy-associated problems like pre-eclampsia and diabetes – and I haven’t seen any evidence that these occur more commonly in vaccine recipients.
“The main issue is balance of risk and benefit and the reason we don’t offer Covid vaccines to healthy children or pregnant women (anymore) is not because of vaccine side effects but because the infection itself doesn’t cause serious problems in these groups, at least not in recent times.
“It is important, in science, to draw a clear distinction between association and causality. In other words, if 2 things seem to happen together, it might mean that one caused the other, but it isn’t necessarily so. It’s a good idea to look out for things that happen together, but once you spot them, there’s more work to be done to figure out what, if any, relationship exists between them. Jumping to conclusions, which may be false, is just as bad a failing as not bothering to look out for problems. Above all, it’s critical to approach evidence with an open mind. If you already have decided the answer to your question, you won’t be able to assess the evidence objectively. If you want to identify whether someone is a scientist, ask them for an example of a time they changed their mind about something when they saw the evidence. As regards vaccine safety, we collect information about anything that happens and then, very carefully, assess whether there is a causal link of not. When there is, we generally find out pretty quickly and take action without delay.”
Prof Dimitrios Siassakos, Professor in Obstetrics and Gynaecology, University College London (UCL), said:
“The evidence in the literature, and also our own data at UCLH, suggest that adverse pregnancy outcomes have been more common in women unvaccinated for COVID than women vaccinated. There has been no substantiated harm to pregnant women from vaccination. The risks to pregnancy from some infections, including COVID, can be significant. As always, it is a balance of risks and benefits – in this case proven benefits versus postulated and unproven risks.”
Dr Victoria Male, Lecturer in Reproductive Immunology, Imperial College London, said:
“The safety of mRNA COVID vaccines during pregnancy has been very intensively studied. I know of 49 studies, looking at outcomes for more than half a million mothers and babies following COVID vaccination in pregnancy, compared to those who did not receive the vaccine. None of these found mRNA COVID vaccination associated with any problems in pregnancy, at birth, or in babies up to 18 months old.
“Some studies done at the height of the pandemic even found COVID vaccination associated with reduced risks of hypertensive disorders of pregnancy, preterm birth and stillbirth. This is likely to be because COVID infection can cause these problems in unvaccinated, but not vaccinated, individuals.”
General comments on vaccine safety:
Prof Adam Finn, Professor of Paediatrics, University of Bristol, said:
“It is important, in science, to draw a clear distinction between association and causality. In other words, if 2 things seem to happen together, it might mean that one caused the other, but it isn’t necessarily so. It’s a good idea to look out for things that happen together, but once you spot them, there’s more work to be done to figure out what, if any, relationship exists between them. Jumping to conclusions, which may be false, is just as bad a failing as not bothering to look out for problems. Above all, it’s critical to approach evidence with an open mind. If you already have decided the answer to your question, you won’t be able to assess the evidence objectively. If you want to identify whether someone is a scientist, ask them for an example of a time they changed their mind about something when they saw the evidence. As regards vaccine safety, we collect information about anything that happens and then, very carefully, assess whether there is a causal link of not. When there is, we generally find out pretty quickly and take action without delay.”
Comments from our friends at the Australian SMC:
Professor Kristine Macartney, Director of the National Centre for Immunisation Research and Surveillance (NCIRS) Australia, and a Professor in the Discipline of Paediatrics and Child Health at the University of Sydney, said:
“Many highly advanced systems and rigorous scientific methods are used to ensure the safety of vaccines at all stages of their development and delivery. Recently, an increasing amount of false and misleading information is being promoted as ‘scientific’, but it is in fact not. These claims are part of a concerted effort that seeks to undermine the safety of and need for vaccines.”
COVID vaccines
“COVID-19 vaccines saved tens of millions of lives globally and continue to protect those most at risk of severe COVID-19, particularly older adults and people with underlying medical conditions. There were a small number of deaths linked with the viral vector vaccines (that are no longer in use) and there is low risk of myocarditis following mRNA COVID-19 vaccines, such as in young males. However, this fact has been distorted to exaggerate the number of deaths.”
Safety surveillance systems
“The US Vaccine Adverse Event Reporting System (VAERS), similar to the Australian Adverse Events Monitoring System (AEMS), accepts any report of any concern at any time from anyone. Reporting of AEFI (adverse events following immunisation) are encouraged so that scientists can look for signals of anything unexpected. These reports don’t mean the adverse event was caused by immunisation. Many of the reported events may be coincidental or from another (often unknown) cause. Rigorous clinical, scientific and epidemiologic methods are necessary and are used to explore if vaccines increase the chance of a person having an unwanted health event. “
Vaccines and autism
“For almost 30 years, initially based on one completely discredited study for which the lead author was deregistered for malpractice, many false theories have been invented to suggest that vaccines cause neurological or developmental conditions such as autism. Dozens of high-quality studies and independent scientists from many countries have shown that vaccines protect against serious diseases and do not cause autism.
“The false theories first blamed MMR vaccine then thiomersal (a harmless preservative), then the harmless trace amounts of aluminium in vaccines (which are used in some vaccines to boost the immune response), as well as the concept of ‘too many shots’ – even though vaccines contain very few antigens and an infant’s immune system is tailored to respond to thousands of different new stimuli in the environment from the moment of their birth.
“Vaccines are carefully designed, evaluated, and delivered to help keep people healthier. Thousands of highly trained scientists, healthcare workers, and public health officials across the globe contribute to these efforts.”
Associate Professor Nick Wood, Associate Director of Clinical Research at NCIRS, Australia and Professor in Clinical Vaccinology at the University of Sydney, said:
“There are two items that will be discussed at the first day of the September ACIP meeting focusing on Hepatitis B birth dose and MMRV vaccine schedule and timing.
Hepatitis B vaccine dose at birth
“A birth dose of Hepatitis B vaccine has been given to millions of children worldwide, and it is safe. Hepatitis B virus is very infectious. Life-long hepatitis B infection occurs in 90% of people infected as babies, and this can lead to long-term liver disease and liver cancer. Newborns infected with hepatitis B at birth and infants infected in the first year of life have a 90% chance of developing chronic hepatitis B, and 25% of those who develop chronic hepatitis B will die from the disease.
“Hepatitis B virus has no cure. Hepatitis B virus is often carried by people who don’t know they are infected. Up to 1.1 per cent of Australians have been diagnosed with hepatitis B, but almost half of all infected people don’t know they have it.
“Perinatal exposure typically occurs during labour and delivery. Due to the elevated risk of chronic infection, and the fact that hepatitis B screening during pregnancy is not uniform, and the potential that infection may occur post-screening, a birth dose is recommended by the WHO and many other countries, including Australia. Hepatitis B vaccine alone is 75% to 95% effective in preventing perinatal hepatitis B transmission when given within 24 hours of birth.
“Since the introduction of funded universal infant hepatitis B immunisation, Australia has seen a threefold decline in the rate of newly acquired hepatitis B notifications between 2000 and 2019. Eliminating the birth dose would reverse progress made in preventing Hep B infections and lead to more cases of perinatally acquired hepatitis B and hepatitis B infections throughout childhood. The birth dose, followed by 3 further doses in infancy, provides long-term protection (>20 years) and continues to provide protection when a person enters the higher risk periods of adulthood and adolescence.
“The Hepatitis B vaccines used in Australia do not contain the mercury preservative thiomersal. The vaccines do contain 0.25mg of aluminium, which is not harmful. This is a small amount when compared to what babies usually get through their diet (over a six-month period, about 7mg of aluminium through breast milk and 38mg through formula)”
MMRV vaccine schedule and timing
“The first dose of MMR vaccine is given in Australia at 12 months old, followed by a booster dose at 18 months old using a combination MMR and varicella (MMRV) vaccine. 2 doses of MMR is highly (>95%) protective against measles, mumps and rubella. Febrile seizures (FS) are common in children and usually happen between 6 months to 6 years of age and usually follow an infection, commonly viral. One child in 30 will have a febrile seizure as a result of fever.Fever and febrile convulsion are known side effects of MMR and MMRV vaccines and are higher in young children who received MMRV vaccine as their 1st dose.
“The US uses a 2-dose series with doses at age 12–15 months and age 4–6 years. MMR or MMRV may be administered, and they recommend that for dose 1 in children aged 12–47 months, MMR and varicella vaccines be administered separately. However, MMRV may be used if parents or caregivers express a preference. This is because of the slightly higher risk of a FS after MMRV as dose 1. Post-marketing studies in the United States identified an approximately 2-fold increased risk of fever and febrile convulsions 7–10 days (or 5–12 days) after vaccination in children who received the MMRV vaccine as a 1st dose. MMRV recipients were compared with recipients of separate MMR and varicella vaccines. MMRV vaccination resulted in 1 additional febrile seizure for every 2300 doses compared with separate MMR and varicella vaccination. Children in these studies were mostly 12–23 months of age. (Reference: https://immunisationhandbook.health.gov.au/contents/vaccine-preventable-diseases/measles#recommendations)
“In Australia, MMRV is not given as the first dose and is instead given as the second dose at 18 months. Australian studies have supported the safety of this schedule timing. The estimated excess annual number of febrile seizures post MMR at 12 months of age was 24 per 100,000 vaccinated children aged 11-23 months (95% CI=7-49 cases per 100,000) or 1 case per 4167 doses.
However, there is no increased risk of FS when MMRV is given as the second dose (1). Even if a child has a febrile seizure after vaccination, their outcomes are no different to FS following a fever from another cause, such as an infection (2). “
Hepatitis B References:
https://thewomens.r.worldssl.net/images/uploads/fact-sheets/HepatitisBimmunisation-and-your-baby-2021.pdf
https://www.aap.org/en/news-room/fact-checked/fact-checked-hepatitis-b-vaccine-given-to-newborns-reduces-risk-of-chronic-infection/?srsltid=AfmBOopH7MXf4Gv5W7gzFDcmOlUL-ED7Q-TCFbimYv1aQStIUjxWz6cA
https://immunisationhandbook.health.gov.au/contents/vaccine-preventable-diseases/hepatitis-b
MMRV References:
(1)JAMA Pediatr. 2017 Oct 1;171(10):992-998. doi: 10.1001/jamapediatrics.2017.1965.
(2)Deng et al. Pediatrics. 2019 May;143(5):e20182120. doi: 10.1542/peds.2018-2120
Dr Charlie McLeod is the Deputy Director at the Wesfarmers Centre of Vaccines and Infectious Diseases based at The Kids Research Institute Australia, said:
“The safety of COVID-19 vaccines has been extensively tested and closely monitored worldwide. In Australia, approved vaccines passed rigorous clinical trials and continue to be tracked through AusVaxSafety—a national surveillance system working with the Therapeutic Goods Administration and health departments to ensure vaccine safety.
“Over 6.8 million safety surveys in Australia, and billions of doses globally, confirm that COVID-19 vaccines are safe and effective. Most side effects are mild and short-lived, such as sore arms, tiredness, headaches, muscle aches, and chills.
“Rare but serious side effects like myocarditis (heart inflammation) have been linked to mRNA vaccines, especially in males aged 15–40 after the second dose. Another rare condition, TTS, was associated with the AstraZeneca vaccine, which is no longer available for use.
“Importantly, no deaths related to COVID-19 vaccination have occurred in children or teens in Australia.
“Vaccination remains an important way to protect those at risk of severe COVID-19. Annual boosters are recommended for adults aged 65–74 and those aged 18–64 with severe immunocompromise, while those aged 75+ years of age are advised to receive a booster vaccination every 6 months.”
Professor Paul Griffin, Director of Infectious Diseases and Professor of Medicine, Mater and the University of Queensland, said:
What do we know about vaccine safety?
“COVID-19 has been a global health event of unprecedented impact with recorded cases now estimated to exceed 700 million and deaths exceeding 7 million. While the public health emergency of international concern was declared over on the 5th of May 2023, the impact of COVID-19 continues. The ability to rapidly develop a number of vaccines that were approved by regulatory bodies and deployed around the world has undoubtedly had a tremendous impact, with estimates suggesting cases averted as a result of vaccination likely to be at least in the 10s of millions and deaths in the 100s of thousands, if not millions.
“Vaccines for COVID-19 were able to be developed rapidly due to many important innovations and based on many years of research, preparing to be able to more rapidly respond to a novel emerging pathogen such as that responsible for COVID-19.
“All the usual phases of clinical trials (including with placebo controls) were completed with numbers of participants exceeding that usually seen in other similar clinical trials. To achieve regulatory approval, these vaccines (as with all vaccines that are approved by our and other similarly rigorous regulators) demonstrated both high levels of efficacy as well as safety. Once approved, safety as well as effectiveness was continued to be carefully observed, and while it is clear that vaccines for COVID-19 are associated with adverse events (as with essentially any intervention), for the majority of vaccines approved, the rate of related adverse events was such that the benefits outweighed these risks hence these regulatory approvals and associated recommendations have remained in place. The raw number of adverse events may seem high, especially if compared to other vaccines, however, the denominator, or number of doses given in such a short space of time, which is now over 13.5 billion doses of COVID-19 vaccines, does need to be taken into account.
“The distinction between correlation and causation also needs to be considered given the majority of the world’s population has now been vaccinated. This does not mean that anything bad that happens to anyone is a direct result of having received a COVID-19 vaccine.”
On the US Vaccine Adverse Event Reporting System – what it is, its limitations and how it compares to Australia’s vaccine event reporting systems
“Adverse event reporting systems are an important part of the ongoing monitoring of the safety of vaccines, both in the USA as well as here in Australia. We do however, need to make sure that this data is interpreted correctly. The reporting of adverse events or deaths that occur after someone has been vaccinated does not necessarily mean the vaccine directly or even indirectly caused the event or death. Once again, the distinction between correlation and causation is important. The VAERS website provides guidance on interpretation to this effect, even stating, ‘VAERS collects data on any adverse event following vaccination, be it coincidental or truly caused by a vaccine. The report of an adverse event to VAERS is not documentation that a vaccine caused the event’, however, this point is often omitted when this data is used to try to overestimate safety concerns of vaccines (VAERS – Guide to Interpreting VAERS Data)”
On other safety concerns
“When assessing vaccines in clinical trials, for regulatory approval and for ongoing use, safety remains the primary consideration and is very carefully monitored. If it is not abundantly clear that the benefits of a vaccine outweigh the risks that are associated (and there are always some risks), it will not progress through clinical trials, much less be approved and used. Unfortunately, misinformation such as the firmly refuted link between vaccination and autism can cause tremendous harm and undermine trust in vaccination, such that the impact of vaccine preventable diseases is greater than it should be.”
Professor Julie Leask AO, from the Infectious Diseases Institute and School of Public Health at the University of Sydney, said:
“Robert F Kennedy Jr, the head of the US Department of Health and Human Services, has campaigned against COVID-19 vaccines since 2020. He has sacked the leading vaccine advisory committee, the Advisory Committee on Immunization Practices (ACIP), and appointed people with limited vaccine expertise, some of whom have a history of anti-vaccination campaigning.
“The ACIP will meet this week, and there are reports of a plan to present research that misrepresents data from a database designed to monitor vaccine safety, called VAERS. The VAERS database allows people to report an adverse event following immunisation. It doesn’t restrict what is reported, and you see a huge variety of reports, from a true vaccine reaction to a car accident on the drive home from the vaccination appointment. To know if the vaccine caused the problem, you need further investigations. So, VAERS is only one part of a good vaccine safety investigation system.
“Reports also suggest the committee could alter its recommendations for the hepatitis B vaccine. That vaccine is now recommended for all infants at birth. It has helped protect thousands of infants born to mothers who are hepatitis B positive from acquiring that infection during the birth process.
“Any changes to the hepatitis B birth dose vaccine recommendations will see a significant decline in vaccination rates. This happened in the US in 1999 after a temporary suspension of the universal recommendation. Many hospitals failed to reinstate their universal vaccination program in a timely way. There were infants born to hepatitis B positive mothers who missed out on protection against hepatitis B – a disease which can become chronic and cause liver disease and cancer later in life. That first day after birth is this window of opportunity for the baby to have something that can protect them from this disease.
“The impacts of these possible changes to US vaccine recommendations would be insidious. They could undermine confidence in vaccines, but also make vaccine access harder. As people lose access, vaccination rates will decline even further than they have. The impacts can take a while to show themselves, but the result is more preventable disease. This would be tragic.
“In terms of the COVID-19 vaccine that is also on the ACIP agenda, it’s generally very safe. Most people are familiar with the minor side effects, like a sore arm. The mRNA COVID-19 vaccine carries a very small risk of myocarditis – inflammation of the heart muscle. This is usually a condition that people recover from completely. Some take a while longer to recover, as recent Australian research has shown. In Australia, there was one death reported that was thought to be vaccine-related. On the other hand, for older people especially, having a COVID-19 vaccine reduces their risk of being hospitalised and dying from the disease, as Australian research has found. In the US, 232,000 deaths from COVID-19 could have been prevented if people had had the vaccine, according to a 2022 estimate.
“Australians are trying to make sense of all this noise coming out of the US. People want to do what’s best for their health. It’s sad that we’re now having to warn people to be so discerning about what they will hear from the current US government on vaccines.
“Fortunately, in Australia, we have multipartisan support for vaccination, and we are well served by our experts who look carefully at the evidence and are committed to vaccine safety. People can continue to trust Australia’s vaccination recommendations. We need to keep an eye on sentiment trends to see if the US-effect is influencing our uptake.”
Dr Candice Holland, Board Member and Chair of the Advocacy and Policy Committee of the Australasian Society for Infectious Diseases (ASID), said:
“Vaccines are one of the most powerful public health tools, preventing millions of deaths and long-term health consequences from devastating diseases each year. As they are given to healthy persons to prevent disease, robust surveillance systems are in place in Australia and overseas to monitor their safety and promptly flag any potential issues to regulatory bodies. Adverse events following immunisation (AEFI) include any untoward occurrence that follows a vaccine, including signs, symptoms, or abnormal test results. Importantly, these events are not always caused by the vaccine itself; many occur coincidentally. For example, when large populations are vaccinated, some unrelated conditions will naturally occur around the same time as vaccination.
“In Australia, vaccine safety monitoring is robust and informed by multiple sources, including information from peer-reviewed scientific publications and surveillance systems both locally and overseas. Therapeutic Goods Administration (TGA) operates a system comparable to the US Vaccine Events Reporting System (VAERS) and reviews any events identified via voluntary reporting by vaccine service providers, public health units, vaccine recipients or others. This information is publicly available and searchable. They also review whether an event is more likely to occur after a vaccine, compared to the general background rate. Active surveillance is also undertaken in Australia by AusVaxSafety and the Paediatric Active Enhanced Surveillance (PAEDS) collaboration. These systems proactively gather targeted information from vaccine recipients and review medical records to provide a more complete picture of vaccine safety.”
Professor David Trembath, Head of Autism Research at CliniKids at The Kids Research Institute Australia, said:
“Vaccines are safe and do not cause autism. We know this from decades of high-quality research, such as a study in Denmark involving more than half a million children.
“Instead, autism is mostly explained by genetics. It is part of who children are, and not an accident, illness, disease, or event. The vaccine myth – which emerged in the late 1990’s from fraudulent research – is categorically untrue. But it continues to haunt and hurt children and families today.
“There is the emotional toll that comes with parents being told that they did something wrong. There is the physical toll that comes when children are denied immunisations that safeguard their health and sometimes save their lives.
“There is the emotional toll that comes with telling autistic people that they are somehow broken, and in need of cure. And there is the financial toll, when huge sums of money are wasted on research that goes over the same old ground, hoping for a different answer.
“Everyone wants better outcomes for autistic children and their families. Rather than prop up and propagate the vaccine myth, we need to be investing in science, services, and supports that have a genuine positive impact on their lives.”
Declared interests
Prof Adam Finn: AF advises the U.K. government and the WHO on vaccination policy and undertakes paid consultancy for many vaccine developers and manufacturers including GSK and Merck who make MMR vaccines.
Prof Kristine Macartney: NCIRS receives funding from the Australian Government Department of Health, Disability and Ageing and Department of Foreign Affairs and Trade, NSW and other state and territory health departments, Gavi the Vaccine Alliance, the World Health Organization, the NHMRC, the MRFF and the Wellcome Trust, none from pharmaceutical sources.
Kristine is a member of the Advisory Committee on Vaccines (ACV) of the Therapeutic Goods Administration (TGA), the Communicable Diseases Network of Australia (CDNA) and the Australian Technical Advisory Group on Immunisation (ATAGI). She has acted as an expert consultant to the World Health Organisation (WHO) and is a member of the WHO Global Advisory Committee on Vaccine Safety (GACVS) and WHO SAGE working groups. No other conflicts of interest to declare.
Prof Nick Wood: NCIRS receives funding from the Australian government Department of Health, Disability and Ageing and Department of Foreign Affairs and Trade, NSW and other state and territory health departments, Gavi the Vaccine Alliance, the World Health Organization, the NHMRC, the MRFF and the Wellcome Trust, none from pharmaceutical sources.
Nick is a Member of the Advisory Committee on Vaccines (ACV) of the Therapeutic Goods Administration (TGA). Previously received funding from the NHMRC for a Career Development Fellowship and is a previous Churchill Fellow. No other conflicts of interest to declare.
Dr Charlie McLeod: Charlie is Co-lead of the PICOBOO Trial – The Platform Trial In COVID-19 Priming and BOOsting (PICOBOO): The immunogenicity, reactogenicity, and safety of different COVID-19 vaccinations administered as a second booster.
Prof Paul Griffin: Paul is director and scientific advisory board member of the Immunisation Coalition and Director of the AMA Queensland. Paul has received speaker honoraria from companies including Seqirus, Novartis, Gilead, Sanofi and Janssen. His Medical Advisory Board Memberships have included Sanofi, AstraZeneca, GSK, MSD, Seqirus, Moderna, Ferring and Pfizer. He is a Clinical Trial Principal Investigator, including on trials of 8 COVID-19 vaccines.
Prof Julie Leask AO: Julie has declared she has received funding from Sanofi for travel to an overseas meeting in 2024. She is a member of the Australian Advances in mRNA Science annual meeting steering committee. The meeting is sponsored by industry groups, she has received no direct funding.
Dr Candice Holland: Candice has declared she is chair of the ASID advocacy and policy committee and a public health physician, with her usual work involving the investigation of adverse events following immunisation (AEFI) reports.
Prof David Trembath: David has not declared any conflicts of interest.
For all other experts, no reply to our request for DOIs was received.