Statement
Please note: this position statement is specific to COVID-19 vaccines. Emerge Australia’s position statement on general vaccinations can be found here.
Vaccination is a valuable and generally safe tool to reduce the risk of numerous communicable diseases. Coronovirus-19 (COVID-19) vaccines were introduced in Australia in 2021 to protect against the SARS-CoV-2 virus.
As with any medication, there are rare instances where “adverse events following an immunisation” (AEFI) occur[1].
Currently, there is not sufficient research to establish if people with ME/CFS are at higher risk of an AEFI with TGA-approved COVID-19 vaccines.
Some people have reported developing a Long COVID-type syndrome following COVID-19 vaccination. There is insufficient published evidence to draw firm conclusions at this stage, but some evidence is emerging of a “post-acute COVID-19 vaccination syndrome” (PACVS)[2].
Emerge Australia understands the concerns about vaccinations and is monitoring all COVID-19 vaccine-related research closely.
People with ME/CFS should discuss vaccination eligibility, spacing of vaccinations and boosters with their treating doctor who know their individual medical history.
Background / What is the issue?
The primary purpose of vaccination against SARS-CoV-2 is to reduce disease severity, hospitalisation and death3. The Australian population has had access to routine primary and booster doses of TGA-approved vaccines for SARS-CoV-2 since 2021.
There are concerns within the ME/CFS community about the possible risks of AEFI following COVID-19 vaccination. The medical and broader community are also discussing potential risks for a Long COVID-type AEFI for COVID-19 vaccination, sometimes called post-acute COVID-19 vaccination syndrome (PACVS)[2]. The latter is now being examined in research.
Evidence / What does the evidence say?
Can COVID-19 vaccination exacerbate existing ME/CFS?
There is currently no published, peer-reviewed evidence on this issue. The evidence we do have, and discussed below, comes from online surveys. Such research has not been peer-reviewed, so is considered lower quality and less reliable evidence. However, Emerge Australia acknowledges these accounts reflect the lived experience of people with ME/CFS.
People living with ME/CFS need to weigh the risks associated with COVID-19 vaccination against the risks of COVID-19 infection itself.
A large, online survey of 7500 people with ME/CFS found that the majority who received COVID-19 vaccination recovered from the vaccination within two weeks[3]. A significant subset reported still experiencing side effects a month after their second dose (28 – 37% of mRNA recipients and 33% of AstraZeneca recipients). Smaller patient surveys have found similar results, with 19-20% of people with ME/CFS reporting worse health following COVID-19 vaccination[4,5].
By contrast, COVID-19 infection can cause an exacerbation of ME/CFS symptoms for many patients. In one survey of 220 people with ME/CFS who had had a COVID-19 infection:
- 75% reported that their ME/CFS symptoms became worse
- 70% indicated that they had developed new symptoms following the infection
- more than two-thirds indicated that they hadn’t returned to their pre-infection baseline, more than six months after infection6.
Unfortunately, studies that aim to examine the effect of COVID-19 vaccination in people who are either immunocompromised or whose immune system is dysregulated have not included people with ME/CFS[7].
Can COVID-19 vaccinations cause ME/CFS or PACVS in healthy people?
Whether COVID-19 vaccinations can cause ME/CFS has not been studied. However, there is some developing evidence to suggest there may be a link between COVID-19 vaccinations and PACVS. The early evidence for this link was weak, based on single case studies or pre-print studies that had not undergone peer review, though the evidence is developing.
Some higher quality studies are emerging into issues such as postural orthostatic tachycardia syndrome (POTS), which has been observed after a COVID-19 vaccination. POTS is also common in ME/CFS and Long COVID. Further research suggests that those who experience PACVS exhibit distinct changes in antibody response and immune system markers, compared to those who do not[2]. It is unclear whether this response is specific to COVID-19 vaccines, or a reflection of broader risks with vaccines.
The benefits of vaccination still far outweigh the risks. For example, while there is a small risk of developing POTS after a COVID-19 vaccination, the risk of developing POTS after COVID-19 infection is significantly greater[8].
There is also strong evidence that vaccination against COVID-19 may provide some protective benefit against developing Long COVID after a breakthrough infection, which is now common with new SARS-CoV-2 variants[10].
Can COVID-19 vaccination exacerbate or help existing Long COVID?
There is conflicting evidence on the benefits of COVID-19 vaccination on existing Long COVID. Published findings come from a range of studies, including small studies or online polls through to systematic reviews[8–11].
A large systematic review found mixed evidence, with some studies finding an improvement in pre-existing Long COVID symptoms after COVID-19 vaccination, and other studies finding either exacerbation or no change[8].
Emerge Australia’s Position
ME/CFS, Long COVID, PACVS and COVID-19 vaccination research is scarce. This makes it difficult to establish the risk of AEFI for people living with these conditions.
Emerge Australia is not aware of any studies that include people with ME/CFS as part of COVID-19 vaccination research. People with ME/CFS should be included in such trials to understand how protective vaccines are in this population and if there are additional or specific risks for AEFIs.
Emerge Australia supports vaccination against COVID-19 as recommended by the Australian Technical Advisory Group on Immunisation (ATAGI). We encourage people to discuss their individual concerns with their treating medical provider.
References
- Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook. Australian Government Department of Health and Aged Care, Canberra. https://immunisationhandbook.health.gov.au (2022).
- Semmler, A. et al. Chronic Fatigue and Dysautonomia following COVID-19 Vaccination Is Distinguished from Normal Vaccination Response by Altered Blood Markers. Vaccines (Basel) 11, 1642 (2023).
- Cort Johnson. Health Rising’s Coronarvirus Infection and Vaccine Side Effect Poll: Take II. Health Rising; https://www.healthrising.org/blog/2021/11/03/health-risings-coronarvirus-infection-and-vaccine-side-effect-poll-take-ii/ (2021).
- Associated New Zealand ME Society (ANZMES). Preliminary Survey Findings. https://anzmes.org.nz/anzmes-preliminary-survey-findings/. Associated New Zealand ME Society (ANZMES) (2021).
- Solve ME/CFS, Y. Registry. After Vaccination, Health of People with Long Covid More Likely to Improve or Worsen Compared to Controls. . https://solvecfs.org/wp-content/uploads/2022/02/You-ME-Registry-Post-Vaccine-Long-Covid-Survey-Results.pdf (2021).
- Action for ME. Survey results so far: impact of COVID on ME. . https://www.actionforme.org.uk/news/survey-results-so-far-impact-of-covid-on-me/ (2021).
- National Institute of Allergy and Infectious Diseases. Analysis of the Immune Response to COVID-19 Vaccination and Outcomes in Individuals With and Without Immune Deficiencies and Dysregulations. . https://clinicaltrials.gov/study/NCT04852276#contacts-and-locations (2021).
- Notarte, K. I. et al. Impact of COVID-19 vaccination on the risk of developing long-COVID and on existing long-COVID symptoms: A systematic review. EClinicalMedicine 53, 101624 (2022).
- LongCOVIDS0S, U. of E. & U. of Kent. The impact of COVID vaccination on symptoms of Long COVID. An international survey of 900 people with lived experience. https://3ca26cd7-266e-4609-b25f-6f3d1497c4cf.filesusr.com/ugd/8bd4fe_7301ed588cc44d1483e9fc8df7989a03.pdf (2021).
- Arnold, D. T. et al. Symptoms After COVID-19 Vaccination in Patients With Persistent Symptoms After Acute Infection: A Case Series. Ann Intern Med 174, 1334–1336 (2021).
- Nayyerabadi, M. et al. Vaccination after developing long COVID: Impact on clinical presentation, viral persistence, and immune responses. International Journal of Infectious Diseases 136, 136–145 (2023).
