Addressing misinformation about excessive DNA in the mRNA vaccines

The Therapeutic Goods Administration (TGA) is aware of misinformation in recent media and online reports that claim the COVID-19 mRNA vaccines are contaminated with excessive levels of DNA. This is not the case.

These reports are based on studies conducted by a small number of laboratories that have attempted to investigate the amount of DNA in COVID-19 vaccines.

While the TGA welcomes and constantly reviews the latest scientific evidence about the safety of vaccines and other biotechnology products, these recent studies fail to apply the required scientific rigor expected in pharmaceutical testing. As such, the results are not robust or reliable, and are creating confusion and concern regarding the safety of vaccines.

Many of our concerns are listed below.

The TGA reassures the public that all COVID-19 vaccines approved in Australia have been rigorously assessed and meet our high standards for safety, quality, and efficacy.

Vaccination against COVID-19 is one of the most effective ways to reduce the risk of death and severe illness from infection. The protective benefits of vaccination far outweigh the potential risks. This statement from medicine regulators around the world provides more information on the good safety profile of COVID-19 vaccines.

For more information on how we approve and regulate COVID-19 vaccines, see COVID-19.

This statement represents the TGA’s views on the scientific evidence as at 18 October 2024.

Misinformation alleging DNA contamination in the COVID 19 vaccines

Some laboratories have attempted to investigate the amount of DNA in COVID-19 vaccines. This has led to a number of incorrect media and online reports circulated on social media about the safety of mRNA COVID-19 vaccines. These reports are based on studies that currently fall short of the scientific rigor expected in pharmaceutical testing and are contributing to the spread of vaccine misinformation.

Concerns with these studies include:

Selective reporting and method validation

• Some laboratories have chosen to report DNA levels using a test called fluorometry, which is known to overestimate DNA levels in the presence of mRNA. This is because the fluorescent dye used in this test binds to both DNA - which may be present in minute amounts - and mRNA, which is the main ingredient in the COVID-19 vaccines. This leads to incorrect DNA levels being reported in these tests.
• Methods for testing medicines are evaluated and approved by regulatory authorities, which require evidence that those methods are suitable for the intended purpose. The guideline used by the TGA and other regulators to assess the performance of test methods is ICH Q2(R2) Validation of Analytical Procedures - external site, developed by the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH). This provides performance criteria that a test method must meet to demonstrate that its results are reliable and accurate. Using these criteria, the fluorometry method used in the quoted tests to measure residual DNA does not meet the requirement for specificity. Specificity means the ability for the test to measure the substance of interest (in this case DNA) without measuring other similar substances (such as mRNA).
• The physical reference materials were not adequately defined.

Issues with samples

• Some of these studies use a very small sample number, for example only three vials. The studies also used samples that were well past their use by date. Some samples had already been opened and used. These samples were not suitable for testing.

• The provenance of the samples is also not clear. This means that significant information is not known about the vials used:

  • where the vials were sourced
  • their location, custody, or temperature before or during testing.

  Regulatory testing is conducted within tightly controlled frameworks to ensure that test samples cannot be manipulated, and results can be relied upon. Processes that do not ensure traceability and certainty about the integrity and provenance of test samples impact the reliability of findings.

• Vaccine vials are required to be shipped via ‘cold chain’ where the temperature must be within a specified range and monitored during transportation. Vials shipped to Australia must adhere to these requirements and the TGA checks that this is done. However, the samples used in these studies were not kept in cold chain and usually did not have temperature loggers with them.

Laboratory status

• The accreditation status of the laboratories is unknown. There is no evidence that these laboratories have Good Manufacturing Practice (GMP) certification, which is required by laboratories to perform approved testing for pharmaceutical companies. Nor do the laboratories appear to have accreditation to the international standard ISO/IEC 17025 : General requirements for the competence of testing and calibration laboratories. These types of accreditations ensure that the results they produce are robust and reliable.

Biotechnology medicines have been available since the 1980s

DNA is an approved starting material for many biotechnology products. This includes recombinant proteins such as insulin, growth factors, cancer medicines, autoimmune therapies and other vaccines, as well as mRNA vaccines such as Comirnaty and Spikevax.

Residual DNA may be present in very small quantities in the mRNA COVID-19 vaccines and other biotechnology products. Residual DNA is the amount of DNA remaining after processing and purification of the medicine and is present as small fragments. Products that use DNA as a starting material have strict limits on the amount of residual DNA which can be present in the final medicine.

Medicines produced by biotechnology have been used by millions of patients for over 40 years. In that time, medicines containing residual DNA quantities under the required limits have presented a very low risk to human safety.

The ability of the manufacturer to minimise amounts of residual DNA and reliably test for it during the manufacturing process is rigorously evaluated by the TGA and other international regulators prior to approval.

The manufacturing protocol and test results must be provided to the TGA for each batch of vaccine released in Australia. Every final batch of the mRNA COVID-19 vaccines released in Australia has met the regulatory requirements for residual DNA concentration. To date, the TGA has also independently tested 27 batches of COVID-19 mRNA vaccines by qPCR to confirm the residual DNA concentration in the final product. The vaccines met the required limits for residual DNA.

The quality limits ensure that there is less than 10 ng present per dose - or less than ten billionths of a gram in each dose. These limits are used by the TGA, the World Health Organization, the United States Food and Drug Administration and other international regulatory agencies.

Residual DNA in Biotechnology Products - safety

To date, neither the TGA nor any international regulator has established a causal link between COVID-19 vaccines and any type of cancer.

There has been no evidence of mRNA vaccines or biological medicines used in Australia resulting in integration of residual DNA into human DNA genome. This includes products such as insulin, which are injected multiple times a day for life-long treatments.

Furthermore, in the combined reproductive and development animal studies using 200-times the clinical dose of mRNA vaccines, there were no adverse effects on male or female fertility, fetal deaths, birth defects, or developmental delays.

Evidence from the more than 13 billion vaccine doses given worldwide shows that COVID-19 vaccines have a very good safety profile in all age groups. The benefits of the approved vaccines far outweigh the possible risks.

Contact for members of the media:

• Email: news@health.gov.au
• Phone: 02 6289 7400.