Should I Worry About Ingredients In My Vaccines?

Should I Worry About Ingredients In My Vaccines?
Should I Worry About Ingredients In My Vaccines?
Emma Yasinski
Emma Yasinski Senior Reporter

You may read the ingredients in your food. You might scan the ingredients of your medications. But, do you know what is in your vaccinations? 

Typically, ingredients are included to create immunity, allow it to be long-lasting and safe, while still being effective. The Centers for Disease Control and Prevention (CDC) notes that the ingredients included fall into the categories of:

  • Stabilizers
  • Adjuvants
  • Residual Inactivating Ingredients
  • Residual Cell Culture materials
  • Residual antibiotics
  • Preservatives.

While you often hear about the active ingredients of vaccines, such as the mRNA, the attenuated virus, or viral particles designed to wake up our immune systems and prime them to respond to future, more potentially virulent, attacks, there are several other ingredients that go into creating vaccines.

Many vaccines include antibiotics. For example, the newer monkeypox vaccine, Jynneos, contains Cipro (ciprofloxacin), an antibiotic that belongs to a class of antibiotics that’s been awarded several black box warnings. MedShadow’s founder, Su Robotti, wrote about the dangers of this particular type of antibiotic in 2018, when more than 75 readers told MedShadow they’d had bad experiences with the drugs. 

MedShadow reached out to Paul Offit, MD, director of the Vaccine Education Center and a professor of pediatrics at the Children’s Hospital of Philadelphia, to explain what antibiotics like Cipro are doing in vaccines, and whether or not you need to worry about them.

MedShadow: Aside from the antigen or mRNA that we always hear about, what are the other common core components of vaccines?

Paul Offit: Sometimes vaccines contain adjuvants, which are chemicals that help to improve the immune response, therefore allowing for fewer doses or lesser quantities of the active component in the vaccine. 

Sometimes vaccines contain inactivating agents, which are chemicals that for example, completely inactivate a virus. You’d see those, for example, in the Hepatitis A vaccine. 

Sometimes vaccines contain manufacturing residuals. So for example, viruses grow in cells, so sometimes there’s very, very trace amounts of cellular material in vaccines.

MedShadow: Why would vaccines contain antibiotics?

Paul Offit: So when you grow cells in culture, you have a fluid that sits on top of those cells, and you want it to be sterile. To make sure that it’s sterile, one often puts antibiotics in the media to make sure that that culture remains sterile. 

During the process of making the vaccine, very, very small amounts of antibiotics could end up then in the final product, but not at a level that would ever be harmful, not at a level that would ever for example, kill bacteria. It would be well below what would be a level of antibiotics that would kill bacteria. 

Also the antibiotics that are used tend not to be the kind of antibiotics like the “cillens” like penicillin, or ampicillin, or cephalosporins, or sulfa drugs that can be more allergenic. So, that’s why you occasionally see very, very small amounts of antibiotics and some vaccines.

MedShadow: Why are there different types of antibiotics in different vaccines?

Paul Offit: Generally they are sort of broader spectrum antibiotics that can kill a variety of different bacteria, and there are many different broad spectrum antibiotics, not just one type of antibiotic that’s [always] chosen.

MedShadow: When used to treat bacterial infections, the antibiotic Cipro has received some black box warnings. What would you say to people that are worried about the fact that Cipro is found in the Monkeypox vaccine, Jyennos?

Paul Offit: Again, the quantity of antibiotics and vaccines are well below the level that would ever have an effect. They would never be able to kill bacteria or change your microbiome. There’s no reason to worry about the quantities that are contained in vaccines.

You probably are exposed to those quantities just living on this planet, given that animals [we eat] are often fed antibiotics, and antibiotics often end up in the water we drink. There’s no avoiding antibiotics because it’s in our water supply.

MedShadow: Should people who have allergies to particular antibiotics be concerned? Should they ask if their vaccines contain antibiotics, and which ones, or is the quantity present that low that even they don’t need to worry about it? 

Paul Offit: It’s that low that they don’t need to worry about it. The thing that you should worry about in terms of having a severe or immediate hypersensitivity or allergic reaction is gelatin. It’s primarily porcine gelatin that’s used in vaccines as a stabilizing agent. It’s used in some of the live, weakened viral vaccines. That can cause an allergic reaction.

It used to be that egg proteins that could be found in the influenza vaccine could cause an allergic reaction, but the quantity of egg proteins in vaccines now is so low that even that doesn’t cause an allergic reaction. Sometimes the latex stopper that is used in vaccines can, for people who are latex allergic, cause a problem, but antibiotics really don’t do that.