A deacon-doctor speaks on the ethics of vaccines

Michie · Jun 26, 2025

As questions and concerns are often raised about the ethics of vaccines, OSV News’ Charlie Camosy recently spoke on these matters with Timothy P. Flanigan, a doctor and professor of medicine in the Infectious Diseases Division of the Miriam and Rhode Island Hospitals and Brown Medical School. Flanigan also serves as a permanent deacon in the Diocese of Providence, Rhode Island.

Charlie Camosy: Can you first tell us a bit about your academic and research background? And how it’s related to your faith commitments?

Timothy Flanigan: I am an infectious disease physician, and on the faculty of the Alpert Medical School of Brown University and a permanent deacon in the Diocese of Providence, Rhode Island at St Theresa and St Christopher Church in our home town of Tiverton.

I’ve provided infectious disease care to adult patients for over 30 years and taught students and fellows in our program. It’s been an incredible privilege to be a permanent deacon for over 10 years. What a joy to be both a deacon and a doctor!

Camosy: This issue has been around a long time, and it certainly revved up during the pandemic, but it is now back with the current administration in a new way: And that is the debate over how modern-day vaccines relate to the abortion. In particular, what do you think about the claim that the measles, mumps, and rubella (MMR) vaccine contains “aborted fetus debris?”

Flanigan: It used to be commonplace for vaccines to be produced using cell lines that were derived from fetal cell lines that were originally derived from an aborted fetus. This is a serious issue, and fortunately most vaccines now do not utilize cell lines that were originally associated with an abortion.

Unfortunately, the MMR (measles, mumps, rubella) vaccine, as well as Hepatitis A and childhood varicella vaccines do utilize cell lines that were derived from aborted fetal cells decades ago. These vaccines contain purified attenuated virus and absolutely do not contain “aborted fetus debris”.

Camosy: Good science is necessary for good ethics, of course, but science alone cannot give us ethical norms. How, in your view, should Catholics and others should think about the ethics surrounding use of vaccines? Especially those which have some relationship to abortion?

Continued below.