COVID19 Vaccines The Immune System Vaccines and COVID19

COVID-19 Vaccines The Immune System, Vaccines, and COVID-19 @mini. PCR Facebook. com/mini. PCR @mini. PCR © 2020 by Amplyus LLC

Overview • What is SARS-Co. V-2? • What is a vaccine? • How do we develop vaccines? • How do vaccines help us and others? • How does our immune system respond? • How are we developing vaccines against COVID-19? • Q&A © 2020 by Amplyus LLC

What is a virus? • DNA or RNA genome • Enclosed in some sort of shell • Can infect a range of hosts – bacteria, animals, plants, humans Image: CDC © 2020 by Amplyus LLC

SARS-Co. V-2 and COVID-19 Rabi et al. 2019 © 2020 by Amplyus LLC

What is a vaccine? • Some portion of a weakened or dead virus/bacteria presented to your immune system • Teaches your immune system what the infection looks like • Allows it to create antibodies that help it fight the disease on future infection © 2020 by Amplyus LLC

A world before vaccines • Before vaccines, common diseases killed huge portions of the population • In the last hundred years of its existence smallpox killed “at least half a billion people. ” - D. A. Henderson (2009) – Smallpox: The Death of a Disease Image: CDC/James Hicks © 2020 by Amplyus LLC

History and first vaccines • Variolation: Dried smallpox scabs were blown or inhaled into an individual’s nose to help them develop immunity. • Inoculation: similar principle but introduced through the skin © 2020 by Amplyus LLC

History and first vaccines • 3/10 people who got smallpox died • Variolation/Inoculation were helpful but came with risks • Edward Jenner created the first vaccine using cowpox in the late 1700 s Image: Wellcome Library © 2020 by Amplyus LLC

History and first vaccines • The creation of the smallpox vaccine was a critical turning point in vaccine history © 2020 by Amplyus LLC

History and first vaccines • Smallpox stats: • Last natural outbreak in the US was in 1949 • May 8, 1980, the 33 rd World Health Assembly officially declared the world free of this disease – officially eradicated • Large scale adoption of this and other early vaccines helped save millions of lives Image: Our. Worldin. Data © 2020 by Amplyus LLC

Chickenpox Image: Britannica Pro Con © 2020 by Amplyus LLC

Modern Day important vaccines • Now, diseases that used to be scary and commonplace are very rare in places with wide access to and adoption of vaccines • Vaccines are also not just for us! Also help us keep our pets and agricultural animals healthy © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How do vaccines help us and others? • This is called Herd Immunity, or Community Immunity • Slows down the spread of the disease • Protects people who cannot get the vaccine due to age or illness Infected Vaccinated Not Vaccinated © 2020 by Amplyus LLC

How many kinds of vaccines are there? • There are different types of vaccines, but they all work on similar principles: create a response in the immune system that will allow your body to fight an infection faster the second time around Inactivated Subunit Attenuated Toxoid © 2020 by Amplyus LLC

Different types we use right now • Live attenuated vaccines • Weakened form of the bacteria/virus • Often create strong, lifetime immune responses • Have to be kept refrigerated, so don’t travel well to remote locations • Often cannot be given to people with compromised immune systems • Examples: Chickenpox, Smallpox, MMR, Typhoid © 2020 by Amplyus LLC

Different types we use right now • Inactivated Vaccines • Use a killed version of the bacteria or virus • Not as strong immunity, may need multiple boosters • Examples: Flu, Polio, Rabies, Hepatitis A © 2020 by Amplyus LLC

Different types we use right now • Subunit, recombinant, polysaccharide, and conjugate vaccines • Use only pieces of the bacteria or virus to create an immune response • The immune system only respond to that piece, and can give a strong targeted response • Examples: HPV, Shingles, Whooping Cough © 2020 by Amplyus LLC

Different types we use right now • Toxoid Vaccines • Use a toxin created by the virus or bacteria, so the immune system responds to the product rather than the germ itself • Examples: Diphtheria, Tetanus © 2020 by Amplyus LLC

How does our immune system respond? The Innate Immune System The Adaptive Immune System • Non-specific responses • Specific to an invading virus or bacteria • Physical barriers – skin and mucous membranes • Recognize patterns in pathogens like bacteria • Inflammation, fever, natural killer cells • First line of defense, but no memory • Antibodies and Antigen Presenting Cells • Coordinated immune response from a number of different cell types • Remembers prior infections for a faster response © 2020 by Amplyus LLC

What does our immune system need to fight a pathogen? • A way to recognize it: antibodies • A way to get rid of it: Neutralizing antibodies and cells that clear out pathogen and infected cells • A way to remember it: memory Bcells • Vaccines allow the body to create and store antibodies against a pathogen without having to go through an infection © 2020 by Amplyus LLC

Vaccines prime our body to fight infection © 2020 by Amplyus LLC

How long does immunity last? • Depends on factors including the type of vaccine, the mutation rate of the virus, etc © 2020 by Amplyus LLC

Why do we sometimes need yearly vaccines, like the flu shot? • The flu mutates, evading our prior vaccines and antibodies • We need to create updated vaccines to keep up • We have to guess what the main strains will about a year in advance so that we can actually produce the vaccines • We can do this quickly because we’re making modifications to something we already had Image: NIAID © 2020 by Amplyus LLC

How do we develop vaccines? • Identify a vaccine target • Regulatory review and licensing • Study the bacteria/virus target • Production • Preclinical trials • Distribution • Clinical trials Image: NEJM © 2020 by Amplyus LLC

Clinical trials for vaccines Preclinical Testing Research on pathogen, animal models Phase 1 Small number of people, looking at safety, dosing, adverse effects Phase 2 Hundreds of people, looking at dosing, safety, and whether or not the vaccine creates a response like antibody production Phase 3 Thousands of people, trying vaccine vs placebo, looking to see if it prevents infection Phase 4 Continued monitoring once we administer to more people © 2020 by Amplyus LLC

How many vaccine trials succeed? © 2020 by Amplyus LLC

Why does it take so long? • We want to make sure it’s safe • We also need to make lots of it! Production takes time. • We need to distribute them! Who gets them first? How do we distribute them equitably? © 2020 by Amplyus LLC

Can we take this time to develop vaccines for COVID-19? • “For example, the measles is a highly contagious illness. It's estimated that 94% of the population must be immune to interrupt the chain of transmission. ” – Mayo Clinic • “Experts estimate that in the U. S. , 70% of the population — more than 200 million people — would have to recover from COVID-19 to halt the epidemic. ” – Mayo Clinic • For this reason, a vaccine is our best bet to get there © 2020 by Amplyus LLC

How are we developing vaccines against COVID-19? • Using some traditional strategies, but also trying new things to get us to a vaccine sooner • Different groups are trying all kinds of vaccine strategies against it, but we need something effective and safe that we can make lots of rapidly © 2020 by Amplyus LLC

Attenuated and Inactivated vaccines. • A few foreign companies working on attenuated/inactivated vaccines • But can take longer to produce, and because we don’t know about long term effects of COVID-19 infections, other methods could be better • These are the more traditional methods © 2020 by Amplyus LLC

Protein based • Contain SARS-Co. V-2 proteins but no nucleic acids • Recombinant proteins directly stimulate production of antibodies—doesn’t need to be taken up by a cell and turned into protein first • These are the more traditional methods © 2020 by Amplyus LLC

What is a DNA or m. RNA vaccine? DNA • To understand how it works, we need to understand transcription and translation • Either of these strategies would rely on the body to create the a piece of the virus that would then be recognized by the immune system m. RNA Protein © 2020 by Amplyus LLC

What is an m. RNA vaccine? • We don’t have any m. RNA vaccines yet • But they could advantageous now: • Easy to manufacture m. RNA • Inexpensive • Does not require the infectious virus for vaccine production • But, RNA not super temp stable or immunogenic – need lipid or carrier molecule to get into cells DNA © 2020 by Amplyus LLC

What is a viral vector vaccine? • Why are so many trials trying this method too? • Some viral vectors enter cells carrying nucleic acids and work like DNA/RNA vaccines • Others display the SARS-Co. V-2 antigen on their surface © 2020 by Amplyus LLC

Where are we right now? • You can help: Prevent. Covid. Org © 2020 by Amplyus LLC

How is this happening so fast? Image: NEJM © 2020 by Amplyus LLC

There’s a lot to be hopeful about • Viruses are pervasive, and vaccines are an amazing tool to fight them • Scientists are coming together to fight COVID-19 • You are a part of this story, and together we can all overcome this © 2020 by Amplyus LLC

Q&A • Why do some vaccines need multiple doses and some are able to work with just one? • Please explain why we are being told we should get the flu vaccine to help address the COVID-19 concerns. • How reasonable is it to hope for a safe, effective Covid-19 vaccine before the end of the year? © 2020 by Amplyus LLC

Resources for Teachers • NYTimes Clinical Tracking Page • Webinar with NIH/NIAID • Podcast Talking about Regulatory Reviews • PPT slides and worksheets for this webinar and past webinars https: //www. minipcr. com/educational-resources/ © 2020 by Amplyus LLC

Webinar schedule • October 12: Bio. Bits Structure Function Lab • October 26: mini. PCR Lemur Lab • November 9: mini. PCR CRISPR Lab • November 23: Sleep Lab © 2020 by Amplyus LLC

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