According to the Center for Disease Control, the first case of COVID-19 in the United States was confirmed on January 21st, 2020. The patient was a resident of Washington state who had returned from the city of Wuhan during the previous week. The virus quickly spread across the country, and our lives have yet to return to normal in the nineteen months since. Between the initial wave that began in early 2020, and the current wave from the Delta variant that is now ravaging the country once again, this virus has claimed the lives of over six hundred thousand people in the United states alone. The majority of news coverage has focused on the pandemic from a national or global perspective. And since major metropolitan areas are often hotspots for the spread of infectious diseases (with the spread of COVID-19 being no exception), smaller towns and cities have experienced incredible desolation of their own. While the global scale and impact of this tragedy is paramount, it is also important to consider the devastation that has been torn apart smaller - often rural - communities, and to remember people whose lives have been forever changed. When I moved back from Phoenix, Arizona to my hometown of Owensboro, Kentucky in June I had the opportunity to do just that: to see this pandemic through the lens of a tight-knit community, where there exists a feeling that everybody knows each other. I wondered whether or not Owensboro had experienced the COVID-19 pandemic between March 2020 and June 2021 in the same way that was being portrayed by national news broadcasts. How did one city combat a nationwide pandemic?

Vaccines are modern medicine’s best way of combating the majority of viral and bacterial illnesses and contagions to date. Thanks to the introduction of vaccines since the first uses of them in 1796 (Jenner’s smallpox vaccine), they have drastically reduced figures of disease worldwide, turning once lethal and life changing conditions into minor annoyances; Some of these afflictions have even become nonexistent or even extinct in certain parts of the world outside of a controlled laboratory setting. With many advancements and overwhelming evidence proving their efficiency, it is clear that vaccines have become nothing less than a necessity for everyday healthcare in today’s world. <br/>The greatest contributor to the creation and evolution of vaccines throughout the years is by far the progress and work done in the field of molecular and cellular biology. These advancements have become the bedrock of modern vaccination, as shown by the differing types of vaccines and their methodology. The most common varieties of vaccines are include ‘dead’ or inactivated vaccines, one such example being the pertussis strain of vaccines, which have either dead or torn apart cells for the body to easily fight off, allowing the immune system to easily and quickly counter the illness; Additionally, there are also live attenuated vaccines (LAVs) in which a weaker version of the pathogen is introduced to the body to stimulate an immune response, or a recombinant mRNA vaccine where mRNA containing the coding for an antigen is presented for immunological response, the latter being what the current COVID-19 vaccines are based on. This is in part aided by the presence of immunological adjuvants, antigens and substances that the immune system can recognize, target, and remember for future infections. However, for more serious illnesses the body needs a bigger threat to analyze, which leads to live vaccines- instead of dead or individual components of a potential pathogen, a weakened version is created in the lab to allow the body to combat it. The idea behind this is the same, but to a larger degree so a more serious illness such as measles, mumps, and rubella (MMR) do not infect us.<br/>However, for the past couple of decades the public’s views on vaccination has greatly varied, with the rise of fear and disinformation leading those to believe that modern medicine is a threat in disguise. The largest of these arguments began in the late 90’s, when Dr. Andrew Wakefield published an article under the Lancet with false information connecting vaccinations to the occurrence of autism in younger children- a theory which has since then been proven incorrect numerous times over. Unfortunately, the rise of hysteria and paranoia in people, along with more misinformation from misleading sources, have strengthened the anti-vaccination cause and has made it into a serious threat to the health of those world-wide.<br/>The aim of this thesis is to provide an accurate and thorough analysis on these three themes- the history of vaccines, their inner workings and machinations in providing immune defenses for the body, and the current controversy of the anti-vaccination movement. Additionally, there will be two other sections going in-depth on two specific areas where vaccination is highly important; The spread and fear of the Human Immunodeficiency Virus (HIV) has been around for nearly four decades, so it begs the question: what makes this such a difficult virus, and how can a vaccine be created to combat it? Additionally, in the last year the world has encountered a new virus that has evolved into a global pandemic, SARS-COV 2. This new strain of coronavirus has shown itself to be highly contagious and rapidly mutating, and the race to quickly develop a vaccine to counteract it has been on-going since its first major infections in Wuhan, China. Overall, this thesis will go in-depth in providing the most accurate, up-to-date, and critical information regarding vaccinations today.

The maintenance of proper oral health has been shown to be an integral facet of overall well-being, with relationships studied between the progression of life-threatening diseases and improper oral care. Heart disease, Alzheimer’s disease and arthritis are some of the most common types of diseases that can progress as a result of oral negligence, particularly within the United States, where there is a lack of a universal health care system that encompasses dental care. In addition to the lack of proper access to quality oral care, a lack of adequate education surrounding oral care has been found to be present, particularly in rural and suburban areas in the United States. Project Tooth Fairy, a non-profit volunteer program, was established in order to delve deeper into these issues. This review aims to educate on the correlations between severe disease progression and oral health, as well as to acknowledge the importance of keeping a healthy mouth in regards to overall well-being, through a synthesis of Project Tooth Fairy’s findings.

In the United States, Escherichia coli O157:H7 (E. coli O157:H7) is the most frequent cause of hemolytic uremic syndrome (HUS) and it is also the primary cause of acute renal failure in children. The most common route of the infection is ingestion of contaminated meat or dairy product originating from cattle or vegetables contaminated with bovine manure. Since cattle are the main reservoir for human infection with E. coli O157:H7, the reduction of intestinal colonization by these bacteria in cattle is the best approach to prevent human infections. Intimin is an outer membrane protein of E. coli O157:H7 that plays an important role in adhesion of the bacteria to the host cell. Hence, I proposed to express intimin protein in tomato plants to use it as a vaccine candidate to reduce or prevent intestinal colonization of cattle with E. coli O157:H7. I expressed His-tagged intimin protein in tomato plants and tested the purified plant-derived intimin as a vaccine candidate in animal trials. I demonstrated that mice immunized intranasally with purified tomato-derived intimin produced intimin-specific serum IgG1and IgG2a, as well as mucosal IgA. I further demonstrated that mice immunized with intimin significantly reduced time of the E. coli O157:H7 shedding in their feces after the challenge with these bacteria, as compared to unimmunized mice. Shiga toxin is the major virulence factor that contributes to HUS. Since Shiga toxin B subunit has an important role in the attachment of the toxin to its receptor, I fused intimin to Shiga toxin B subunit to create multivalent subunit vaccine and tested the effects upon immunization of mice with the B subunit when combined with intimin. His-tagged intimin, Shiga toxin B subunit, and Shiga toxin-intimin fusion proteins were expressed in E. coli and purified. I demonstrated that this multivalent fusion protein vaccine candidate elicited intimin- and Shiga toxin B-specific IgG1, IgG2a, and IgA antibodies in mice. I also showed a reduction in the duration of the bacterial shedding after the challenge compared to the control sham-immunized groups.