This video will cover the present recommendations for prevention of COVID-19. When we talk about prevention the first thing everyone asks is, what about a vaccine? Time does not permit a full review of this topic, and I'm not an expert in vaccine development. The protein sequence of S protein nAbs is known, and this would be an ideal target for the vaccine. There are a number of unknowns with regards to which segment the proteins choose. Issues with regards to what adjuvant agent that enhances the immune response should be chosen. Then field testing will need to be performed to prove effectiveness. Experts estimate the minimal timeframe is 18 months. Optimistic earlier time points are being suggested by hopeful politicians, but I recommend assuming this realistic timeframe and promoting the adoption of tried and true infection control methods that have been shown to be effective for centuries. This book entitled Decameron was written in the city of Florence, Italy, in 1350 during the Black Death pandemic. The author describes behavior very similar to what is happening today. Many chose to ignore the mandates to shelter-in-place, and those who went to bars and congregate with others died while those who fled to the countryside and isolated themselves survived. When we ignore history, we'll doom to relive it. That is exactly what is happening in many parts of the United States. I hope other countries will learn from our mistakes. Infection control has been termed non-pharmacologic intervention. As outlined in the Imperial College COVID-19 response teams report of March 16th. There are five tools designed to control the spread of infection. Individual isolation, all infected individuals avoid contact with others and wear masks. They maintain a distance of over six feet. Two, voluntary quarantine. Individuals who have come in contact with the infected patient agree to avoid contact with others for 14 days. Three, social distancing of those over age 70. Four, social distancing of the entire population. Five, closing of schools, universities, and non-essential businesses. These tools can be used to implement one of two basic strategies. Suppression. All five tactics are applied to reduce person-to-person contact to the level that drops the R subzero to below one so the number of new cases progressively decreases and the epidemic is suppressed but not eliminated. Mitigation applies tactics 1, 2 and 4. Isolation, quarantine, and social distancing of the entire population to reduce the R subzero. But the value stays above one. In this approach, the epidemic continues to grow, but at a slower rate. Simulation studies reveal if the mitigation strategy is used, the number of individuals infected will rapidly exceed the capacity of the health system. In this graph, the black line shows what happens if nothing is done. The peak exceeds the ICU bed capacity red line by over 30 fold upper graph. The number of people estimated to die in Great Britain would be 510,000 while in the United States, 2.2 million. If mitigations applied, the orange line, the number of ICU beds required to manage patients would exceed capacity by 35 percent, best seen in the magnified lower panel. The Imperial College team recommends suppression, employing isolation of infected individuals, social distancing for everyone, and school and university closings. Implement banning this approach, the number of infected patients will never exceed the bed capacity and will minimize the number of deaths. The durations of the suppression strategy recommended is three months. Then upon discontinuation, watching closely and triggering isolation in place if a specific number of ICU beds again fill with COVID-19 patients. Discontinuation is allowed when the ICU bed occupancy drops below 50. Over time, the area under the epidemic curve becomes smaller and smaller. Other approaches from monitoring are also possible. For example, an internet connected electronic thermometer sends body temperatures to a smartphone through the company called Kinsa, then to an Internet site allowing real-time regional monitoring of fever. A publication on the clinical infectious diseases in 2018 documented a very close correlation. Correlation coefficient 0.95 between the number of doctor visits for an influenza like illness and then number of individuals with fever. This simple Smartphone application would allow close monitoring of COVID-19. This system can also be used to quickly identify new cases as we open up our businesses and schools. A word about simulations. Think of them as weather forecast. They are not always completely reliable because they are dependent on predicting human behavior, a well-known challenge. Just besides they don't always exactly predict the future, Should we ignore them? Most people now listen to weather reports and act accordingly. Shouldn't we do the same with these epidemic models? In my original video on prevention, I asked several questions. First, will our health system rise to the occasion? The answer originally looked like a yes. Cases did peak in the US on April third and then began to drop after most areas observed shelter-in-place. Unfortunately, less populated states in the US chose to ignore modeling predictions and did not shelter in place continuing on as though there was no epidemic. As a consequence, we have seen multiple outbreaks in many of these states, particularly in meatpacking plants. To make matters worse, many of these states that did embrace the suppression strategy gave in to the economic pressures, entering suppression after only one month rather than three months. As a consequence, US has failed to bring the curve to near-zero. Instead, we are experiencing a prolonged plateau with some states again experiencing exponential growth of cases. With the exception of Brazil, whose President continues to deny the risk of the virus, the US has over three times the cases and three times the number of deaths from COVID-19 of any other country in the world. The consequences have been particularly troublesome in the southern states of South Carolina, Alabama, Mississippi, and Florida. As discussed in the epidemiology video in module 1, the Imperial College has predicted a surge in Florida that is likely to peak in early July. That prediction is presently being fulfilled. On June 20th, Florida experienced over 4,000 cases on one day, up from an average of 500 a day in May. This surge is primarily the consequence of increased mobility, the opening of bars and congregating in large crowds over Memorial Day. Recent massive protests and an in-person political rally promised to foster a continued steep rise in cases in the US, and that will again be taxing our health systems. To summarize the content of this section on prevention, a vaccine will not be available for at least a year, meaning that we will need to adhere to tried and true infection control methods to prevent the spread of SARS-CoV-2 infection and to save lives. That means diagnostic testing, isolation of the infected, quarantining of the contacts, social distancing, and intermittent shutting down of schools and businesses. Modeling of the infection is a form of forecast. These predictions can guide how we should act. These predictions can save lives. Today, our efforts to control the spread of infection in the United States has failed. We represent only four percent of the world's population. However, because of refusal to act, we have over 25 percent of the world's COVID-19 infections. We can and must do better. In the next video, I will outline what each of us needs to do to reduce US and worldwide spread. Thank you.