VEC Vaccine Notes

Vaccine Education Center at Children’s Hospital of Philadelphia

Listen to “VEC Vaccine Notes,” a video and podcast series presented by the Vaccine Education Center at Children's Hospital of Philadelphia. Each episode offers vaccine information in a convenient format, so families have the answers they need to make informed decisions, including details and context that addresses what they may have heard in the news or in conversation with others. This podcast is for general informational and educational purposes only and is not to be considered as professional medical advice for your personal health or for your family's personal health. You should not use it to replace any relationship with a physician or other qualified healthcare professional. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult your physician or, in serious cases, seek immediate assistance from emergency personnel. Clinicians must rely on their own informed clinical judgment in making recommendations to their patients. ©2026 The Children’s Hospital of Philadelphia.

  1. 5d ago

    Preservatives: Thimerosal - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    What is thimerosal, and why was it used as a vaccine preservative? Find out in this episode of VEC Vaccine Notes. Charlotte Moser, Co-Director of the Vaccine Education Center, explains the differences between elemental mercury (the silver-colored form of mercury found in products like thermometers and dental fillings), methylmercury (the type we’re exposed to when we eat fish), and ethylmercury (the preservative used in childhood vaccines). She details why small changes in the chemical structure between two compounds that might sound similar greatly impact the level of toxicity and how they are processed by our bodies. This episode also explores the history of thimerosal in multidose vials, why routinely recommended childhood vaccines in the United States transitioned to single-dose vials in the late 1990s, and what decades of rigorous scientific studies reveal about thimerosal and autism. Hint? Study after study found that thimerosal in vaccines does not cause autism. Check out the video version on YouTube. Listen to the episode to find out: About the worst, single-source mercury poisoning in history How ethanal and methanol can help us think about ethylmercury and methylmercury Symptoms of neurologic damage caused by mercury The different types of studies that looked at thimerosal exposure from vaccines Some of the known causes of autism and why we know mercury isn’t among them To learn more about thimerosal, please visit https://bit.ly/vec-thimerosal.  To learn more about vaccine ingredients, please visit https://bit.ly/vec-vax-ingredients. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  2. Sep 23

    Stabilizers: Gelatin and Polysorbate 80 & Vaccines - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    Find out how gelatin and polysorbate 80 protect vaccines during manufacturing, storage and transport. Charlotte Moser, Co-Director of the Vaccine Education Center, also addresses common safety and cultural concerns related to these two vaccine ingredients, including severe allergic reactions, unfounded claims regarding polysorbate 80 and fertility, and religious guidelines surrounding porcine-derived gelatin. The discussion also includes a comparison of the amounts found in vaccines to exposures encountered in everyday foods and products and clarifies the health effects, safety and practical takeaways for considering both ingredients. Listen to the episode to find out: How gelatin is made The variety of products that contain gelatin and polysorbate 80 Which vaccine contains gelatin made from cows instead of pigs Three reasons religions that do not allow consumption of pig products still support use of vaccines that contain gelatin made from pigs The importance of the chemical structure of polysorbate 80 What micelles are Four types of evidence against the idea that polysorbate 80 causes fertility issues Check out the video version on YouTube. To learn more about gelatin, please visit https://bit.ly/vec-gelatin. To learn more about polysorbate 80, please visit https://bit.ly/polysorbate-80. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. To learn more about vaccine ingredients, please visit https://bit.ly/vec-vax-ingredients. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu/. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  3. Sep 16

    Adjuvants: Aluminum & Vaccines - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    What is aluminum, and why is it used in some vaccines? Find out in this episode of VEC Vaccine Notes. Charlotte Moser, Co-Director of the Vaccine Education Center, explains how aluminum adjuvants boost immune responses, where aluminum exists in our environment, and how quantities from vaccines compare to daily dietary exposure. This episode also covers how the body processes aluminum, why exposure has decreased over time due to combination vaccines, and what scientific evidence reveals about the safety of aluminum in vaccines. Check out the video version on YouTube. Listen to the episode to find out: Why we can’t avoid exposure to aluminum How much aluminum infants are estimated to consume in the first 6 months of life Why even though less than 1% of dietary aluminum reaches our bloodstream, what we eat still accounts for the majority of aluminum in our bodies How aluminum is processed and where it is stored in our bodies Which vaccines contain aluminum (and why live viral vaccines do not have aluminum) Two reasons aluminum exposure from infant vaccines has decreased over time When aluminum does cause health concerns About different studies evaluating the safety of aluminum in vaccines To learn more about aluminum, please visit https://bit.ly/vec-aluminum. To learn more about vaccine ingredients, please visit https://bit.ly/vec-vax-ingredients. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  4. Sep 9

    Types of Vaccine Ingredients - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    Find out what ingredients are in vaccines, whether they’re safe, and how they are measured in this episode of VEC Vaccine Notes. Charlotte Moser, Co-Director of the Vaccine Education Center, breaks down the different types of ingredients in vaccines and why they are used. Guided by Paracelsus’ quote, "the dose makes the poison," this episode covers how relative quantities in vaccines (typically from nanograms to milligrams) compare with ingredient exposures in the context of daily life. Watch the episode to find out: Why avoiding any exposure to a particular vaccine ingredient can be difficult How to consider vaccine risks in the context of other exposures to vaccine ingredients How a raisin can help with estimating quantities The difference between weight-based quantities (like milligrams) and ratio-based quantities (like parts per million) The different types of antigens used in vaccines The three ways adjuvants can make vaccines work better and the five types currently used in the US The different roles of stabilizers and preservatives How manufacturing byproducts are like sand after a day at the beach Check out the video version on YouTube. To learn more about the different types of ingredients in vaccines and why they’re present, please visit https://bit.ly/vec-vax-ingredients.  Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  5. Aug 13

    Season 4 trailer - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    Get ready for Season 4 of VEC Vaccine Notes! Charlotte Moser, Co-Director of the Vaccine Education Center at Children's Hospital of Philadelphia, provides a sneak peek into the new season. While Seasons 1 through 3 covered more than 30 vaccine-preventable diseases, Season 4 turns the focus toward addressing common vaccine safety concerns. Season 4 will dive into the science behind vaccine ingredients, exploring why they are present and taking a closer look at specific components like aluminum, fetal cells, and thimerosal. The first episode about “types of vaccine ingredients” will drop on Sept. 9. Check out the video version of this episode. Get ready for the new season by subscribing to our YouTube channel or following the series where you listen to podcasts. That way, you’ll be sure to get episodes as soon as they become available: VEC YouTube channel VEC Podbean channel Catch up on previous seasons: "VEC Vaccine Notes" webpage "Vaccine Ingredients" web section Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes.   For more information or for general questions about vaccines, check out https://vaccine.chop.edu.   Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  6. Jun 17

    Yellow Fever - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    Charlotte Moser, Co-Director of the Vaccine Education Center at Children's Hospital of Philadelphia, talks about yellow fever and the vaccine. She explains the history of the yellow fever vaccine, how globalization and climate change impact the spread of yellow fever virus, and what steps travelers can take to protect themselves against mosquito bites. She also addresses common questions and the relative risks and benefits of the disease and vaccine. Watch the episode to find out: Who won the Nobel Prize for development of the yellow fever vaccine Two areas of concern related to yellow fever disease control Estimated global number of infections and deaths caused by yellow fever each year The two main health issues caused by yellow fever The known, potentially fatal vaccine reaction and why the vaccine is still used despite this To learn more about yellow fever and the vaccines to prevent it, please visit https://bit.ly/vec-yf. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  7. Jun 10

    Typhoid - VEC Vaccine Notes | Vaccine Education Center at Children’s Hospital of Philadelphia

    Charlotte Moser, Co-Director of the Vaccine Education Center at Children's Hospital of Philadelphia, talks about typhoid and the vaccines. She shares the story of Mary Mallon, who was infamously known as "Typhoid Mary," to illustrate how people can be carriers of the disease, not having symptoms but still spreading typhoid. Moser offers tips on how travelers to high-risk areas can protect themselves from this disease, and she addresses common questions and discusses the relative risks and benefits of the disease and vaccines. Watch the episode to find out: How today’s phrase “Typhoid Mary” came to be and what it means. How many people are estimated to have been affected by Mary Mallon’s carrier status and why. The distinct progression of fever caused by a typhoid infection. Why we say, “Boil it, peel it, or forget it.” The differences between typhoid and typhus. To learn more about typhoid and the vaccines to prevent it, please visit https://bit.ly/vec-typhoid. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

  8. Jun 3

    Japanese Encephalitis Virus (JEV) - VEC Vaccine Notes | Vaccine Education Center at Children's Hospital of Philadelphia

    Charlotte Moser, Co-Director of the Vaccine Education Center at Children's Hospital of Philadelphia, talks about Japanese encephalitis virus (JEV) and the vaccine that protects against it. She explains that the JEV vaccine is considered a travel vaccine, but it’s not recommended for all travelers to the Far East. She discusses the many considerations for making a vaccine recommendation. She also addresses common questions and discusses the relative risks and benefits of the disease and vaccine. Watch the episode to find out: Which Americans are most often affected by JEV The rates of death and permanent harm when someone is infected with JEV What aspects of a trip are considered when deciding who should get the JEV vaccine JEV vaccine recommendations for adopted children who started the vaccine before moving to the U.S. To learn more about JEV disease and the vaccine to prevent it, please visit https://bit.ly/vec-jev. Questions? Submit the VEC Vaccine Notes form, https://bit.ly/contact-vec-vaccine-notes. For other vaccines, diseases or general questions about vaccines, check out https://vaccine.chop.edu. Subscribe to our Parents PACK newsletter, https://bit.ly/3KfLUoO.

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About

Listen to “VEC Vaccine Notes,” a video and podcast series presented by the Vaccine Education Center at Children's Hospital of Philadelphia. Each episode offers vaccine information in a convenient format, so families have the answers they need to make informed decisions, including details and context that addresses what they may have heard in the news or in conversation with others. This podcast is for general informational and educational purposes only and is not to be considered as professional medical advice for your personal health or for your family's personal health. You should not use it to replace any relationship with a physician or other qualified healthcare professional. For medical concerns, including decisions about vaccinations, medications and other treatments, you should always consult your physician or, in serious cases, seek immediate assistance from emergency personnel. Clinicians must rely on their own informed clinical judgment in making recommendations to their patients. ©2026 The Children’s Hospital of Philadelphia.

Information

  • Creator
    Vaccine Education Center at Children’s Hospital of Philadelphia
  • Years Active
    2025 - 2026
  • Episodes
    38
  • Rating
    Clean
  • Copyright
    © Copyright 2025 All rights reserved.
  • Show Website
    VEC Vaccine Notes

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