Trial on ferrets yielded severe hepatitis in mRNA injected specimens.

"Extra caution should be taken in proposed human trials of SARS vaccines due to the potential liver damage from immunization and virus infection"

[link to www.cidrap.umn.edu (secure)]


Trial on mice yielded Th2 hypersensitivity, resulting in destruction of lung tissue.

"challenge of mice given any of the vaccines led to occurrence of Th2-type immunopathology suggesting hypersensitivity to SARS-CoV components was induced. Caution in proceeding to application of a SARS-CoV vaccine in humans is indicated."

[link to journals.plos.org (secure)]


"Type II hypersensitivity is an antibody-dependent process in which specific antibodies bind to antigens, resulting in tissue damage or destruction”

[link to www.sciencedirect.com (secure)]

"There are no specific guidelines for use of messenger RNA (mRNA) vaccines or contraindications to mRNA vaccines.

No large trials of any mRNA vaccine have been completed yet.

The only evidence on safety of mRNA vaccines comes from small phase I and phase II trials of SARS-CoV-2 vaccines, with follow-up typically less than two months.

Systemic adverse events such as fatigue, muscle aches, headache, and chills are common.

Severe systemic adverse events were reported by 5 to 10 percent of trial subjects.

Localized adverse events such as pain at the injection side are common.

Both systemic and local adverse events usually are resolved within one or two days.

The rate and severity of adverse events appears to be higher for the second dose of vaccine than for the first.

Higher vaccine doses appear to increase the rate and severity of adverse events.

Larger trials of SARS-CoV-2 vaccines are in progress, with results expected in mid-2021.

There is not sufficient evidence to support any conclusions on the comparative safety of different mRNA vaccines.

Direct evidence on the comparative safety of mRNA vaccines and other vaccines is lacking."

[link to www.uphs.upenn.edu]