Christopher Woods, MD, Professor of Medicine, Infectious Diseases, Duke University School of Medicine
Adrian Hernandez, MD, MHS, Principal Investigator, HERO Research Program
Executive Director, Duke Clinical Research Institute
At every step of the COVID-19 crisis, we have been challenged by scale and time. From producing and distributing tests, personal protective gear, mechanical ventilators, hand sanitizer, and other needed supplies – getting the public what it needs as fast as needed— has been daunting. The quest to produce vaccines to prevent COVID-19 is expected to be no different. While hundreds of possible vaccines are currently in development, efforts to test these vaccines on a large scale, quickly will be difficult. While the federal government has recently announced plans to fast-track vaccine development, safe and valid testing of vaccine candidates in humans will still play an important role.
Fortunately, the HERO community can help with achieving necessary scale quickly. Indeed, when recently asked, HERO community members reported a vaccine as one of their top priorities for research. Given that HERO community members are at high risk for contracting COVID-19 through their interactions with the healthcare system, they may be among the first to be invited to participate in vaccine trials. As the HERO community gets ready to evaluate when and how to participate in vaccine development, what questions should they be asking? What examples from the past can help us understand the risks and benefits involved?
Vaccines are designed to teach our immune systems how to fight off certain kinds of germs and the serious diseases they cause. Because we need to create vaccines for the entire population, we will likely need to create and use more than one. For example, people with chronic diseases or conditions, children, the elderly, or those living in places without means of refrigeration might have special needs. Many vaccine trials are likely to occur over the coming year testing safety and efficacy.
These different vaccine trials will test different types of approaches ranging from a “weakened” virus to newly developed genetically engineered vaccines that hold great promise but have not been licensed yet for human use. In a series of posts, we will review these different types of approaches to vaccine development, and share the latest so that you can be prepared to make an informed decision about participating in a vaccine trial when it is time.
Today we’ll start by sharing the facts about one type of vaccine – the ‘weakened’ or live-attenuated vaccines.
Live-attenuated vaccines
Live vaccines use a weakened (or attenuated) form of the virus that causes a disease. These vaccines create a strong and long-lasting immune response with just 1 or 2 doses, often providing a lifetime of protection against a germ and the disease it causes. Live vaccines are used to protect against measles, mumps, rubella, smallpox and chickenpox. As a result, the infrastructure is in place to develop these kinds of vaccines.
However, because this type of vaccine contains the actual virus, people with compromised immune systems or long-term health problems need to be cautious and talk to their physicians before taking. Limitations of these kind of vaccines are that they need to be refrigerated and can be hard to transport and use in less developed areas of the world.
Stay tuned next week as we take a deeper dive into other vaccine types. In the meantime, what are your questions about vaccines? Email us and let us know. As always, thanks for joining the HERO community. We can help by not only participating in upcoming trials, but also by helping to educate our friends and family on how vaccines work and their crucial importance in stopping this pandemic.