Sure looks we can build immunity to Covid 19 per this research. Herd immunity could be a very viable goal if you keep the high risk group isolated. https://www.eurekalert.org/pub_releases/2020-05/ljif-dao051420.php "All efforts to predict the best vaccine candidates and fine-tune pandemic control measures hinge on understanding the immune response to the virus," says Crotty, also a professor in the Center for Infectious Disease and Vaccine Research. "People were really worried that COVID-19 doesn't induce immunity, and reports about people getting re-infected reinforced these concerns, but knowing now that the average person makes a solid immune response should largely put those concerns to rest."
Yeah... I would not be so confident the idea of limited reinfection is true in another six months. https://edition.cnn.com/2020/05/21/health/sweden-herd-immunity-coronavirus-intl/index.html Sweden is still nowhere near 'herd immunity,' even though it didn't go into lockdown By Niamh Kennedy, CNN Updated 2112 GMT (0512 HKT) May 21, 2020 Sweden has revealed that despite adopting more relaxed measures to control coronavirus, only 7.3% of people in Stockholm had developed the antibodies needed to fight the disease by late April. The figure, which Sweden's Public Health Authority confirmed to CNN, is roughly similar to other countries that have data and well below the 70-90% needed to create "herd immunity" in a population. It comes after the country adopted a very different strategy to stop the spread of coronavirus to other countries by only imposing very light restrictions on daily life. Sweden's chief epidemiologist Anders Tegnell said the number was a "little lower" than expected "but not remarkably lower, maybe one or a couple of percent." "It squares pretty well with the models we have," he added, while speaking at a news conference in Stockholm. The study carried out by Sweden's Public Health Agency aims to determine the potential herd immunity in the population, based on 1,118 tests carried out in one week. It aims to carry out the same number of tests every seven days over an eight-week period. Results from other regions would be released later, a Public Health Authority spokesperson said. The country has not enforced strict lockdown measures and most restaurants, bars and stores have remained open. Sweden has adopted a different strategy to other Nordic nations during the pandemic, choosing to avoid a lockdown and keep most schools, restaurants, salons and bars open. It did, however, ask people to refrain from making long journeys, placing an emphasis on personal responsibility. The strategy was criticized by Swedish researchers early on, who said that attempting to create herd immunity had low support. But the authorities denied that achieving herd immunity was their goal. Herd immunity is reached when the majority of a given population -- 70 to 90% -- becomes immune to an infectious disease, either because they have become infected and recovered, or through vaccination. When that happens, the disease is less likely to spread to people who aren't immune, because there just aren't enough infectious carriers to reach them. No community has yet achieved this and a vaccine "will get us to herd immunity quicker" than infection, Michael Mina, Assistant Professor of Epidemiology at Harvard T. H. Chan School of Public Health, said in a recent interview with Public Radio International's The World. A healthcare worker cleans and disinfects an ambulance after dropping a patient at the Intensive Care Unit (ICU) at Danderyd Hospital near Stockholm on May 13. Sweden's percentage of people with antibodies is not far off that of other countries that did enforce lockdowns. In Spain, 5% of people had developed coronavirus antibodies by May 14, according to preliminary results of an epidemiological study by the government. According to Martin Kuba, an official Jihocesky region in the Czech Republic who spearheaded a randomly selected mass testing for coronavirus among the general public and frontline workers, the initial results showed that the proportion of people who have had the disease stood at "single digit percent" rather than "fraction of a percent". Michael Osterholm, the director of the Center for Infectious Disease Research and Policy at the University of Minnesota, estimated earlier this month on CNN Tonight with Don Lemon that between 5% and 15% of people in the US have been infected. He said the coronavirus was going to circulate and infect at least 60% to 70% of the population before it slows down, but warned that the country had "a long ways to go" to get to a level of herd immunity. A report he wrote along with other epidemiologists and a historian estimated this would likely take 18 to 24 months. Dr. Mike Ryan, executive director of the World Health Organization (WHO) Health Emergencies Program, said the concept of herd immunity was a "dangerous calculation." Pedestrians and cyclists cross a bridge in the heart of Stockholm on May 11. When asked if he would be comfortable with immunity passports based on his company's tests, CEO of Swiss drugmaker Roche Severin Schwan told CNN's Julia Chatterley: "I do believe that we are in a world with a lot of ambiguity, and we also have to make decisions on incomplete information. So, I do think it is valuable information, but we should not fully rely on it." On April 24, chief epidemiologist Tegnell told BBC radio that the authorities believed Stockholm had "an immunity level... somewhere between 15 and 20% of the population." He said the strategy had "worked in some aspects ... because our health system has been able to cope. There has always been at least 20% of the intensive care beds empty and able to take care of Covid-19 patients." Asked whether Sweden's approach will help it withstand a possible second wave, Tegnell said he believed it would. "It will definitely affect the reproduction rate and slow down the spread," he said, but added that it wouldn't be enough to achieve "herd immunity." But Sweden's foreign minister Ann Linde and Peter Lindgren, managing director at the Swedish Institute for Health Economics (IHE), said last month that it had failed to prevent a high number of deaths in care homes. Sweden has now had 32,172 cases and 3,871 deaths, according to figures from Johns Hopkins University.
Herd Immunity Herd immunity is an important element in the balance between the host population and the micro-organism, and represents the degree to which the community is susceptible or not to an infectious disease as a result of members of the population having acquired active immunity from either previous infection or prophylactic immunization (see p. 731). From: Medical Microbiology (Eighteenth Edition), 2012 https://www.sciencedirect.com/topics/medicine-and-dentistry/herd-immunity Models for the Study of Infection in Populations John R. Williams, in Handbook of Models for Human Aging, 2006 HERD IMMUNITY Herd immunity is essentially a simple concept describing the totality of naturally acquired and vaccine-based immunity to a given infectious agent as a proportion of the whole population. While the individual objective of vaccination is clearly to prevent or reduce the risk of infection for the individual concerned, the public health objective of vaccination is to increase the level of herd immunity to that required for control or elimination of the infection from the population, and in the longer term on a regional or global scale to eradicate the infection altogether. (Note the distinction between elimination where an infectious agent is no longer present in a particular population and eradication in which the agent is eliminated world- or region-wide; the smallpox virus remains, at the time of writing, the only infection for which global eradication has been achieved.) The term herd immunity is occasionally used to describe the level of population immunity that will result in elimination of a specific infection from a population, but here herd immunity for elimination would be more appropriate. This level of herd immunity for elimination is that at which an infection cannot propagate effectively in the population; at this level of immunity there may be some secondary cases or even short chains of infection, but these chains are sooner or later broken and prove insufficient to prevent the infection from dying out. In other words, the effective reproduction number, R, in these circumstances is less than 1.0. Herd immunity is obviously dynamic, as natural or vaccine-based immunity is lost over time through waning of immunological memory or deaths of immune individuals, and newly susceptible individuals arrive through births or migration. Thus to maintain the effectiveness of vaccination programs, vaccine coverage and herd immunity need to be monitored at regular intervals and if necessary a strategy planned, informed by dynamic modeling, of supplementary vaccination programs introduced to boost herd immunity to the necessary level (Nokes and Anderson, 1988).
As noted in the headline of the press release it is good news for a vaccine. It does not mean much for "natural herd immunity" in bulk beyond that it is promising that individuals can demonstrate an immune response across coronavirus types. Nearly the entire text of the press release discusses why this is good news for vaccine development with a focus on crossreactivity. Detailed analysis of immune response to SARS-CoV-2 bodes well for COVID-19 vaccine Study finds robust antiviral T cell response in humans with COVID-19 and detects substantial crossreactivity in unexposed individuals; in a piece of good news provides a benchmark for testing of vaccine candidates https://www.eurekalert.org/pub_releases/2020-05/ljif-dao051420.php Scientists around the world are racing to develop a vaccine to protect against COVID-19 infection, and epidemiologists are trying to predict how the coronavirus pandemic will unfold until such a vaccine is available. Yet, both efforts are surrounded by unresolved uncertainty whether the immune system can mount a substantial and lasting response to SARS-CoV-2 and whether exposure to circulating common cold coronaviruses provides any kind of protective immunity. A collaboration between the labs of Alessandro Sette, Dr. Biol. Sci. and Shane Crotty, Ph.D., at La Jolla Institute for Immunology is starting to fill in the massive knowledge gap with good news for vaccine developers and is providing the first cellular immunology data to help guide social distancing recommendations. Published in today's online edition of Cell, the study documents a robust antiviral immune response to SARS-CoV-2 in a group of 20 adults who had recovered from COVID-19. The findings show that the body's immune system is able to recognize SARS-CoV-2 in many ways, dispelling fears that the virus may elude ongoing efforts to create an effective vaccine. "If we had seen only marginal immune responses, we would have been concerned," says Sette, a professor in the Center for Infectious Disease and Vaccine Research, and adds, "but what we see is a very robust T cell response against the spike protein, which is the target of most ongoing COVID-19 efforts, as well as other viral proteins. These findings are really good news for vaccine development." "All efforts to predict the best vaccine candidates and fine-tune pandemic control measures hinge on understanding the immune response to the virus," says Crotty, also a professor in the Center for Infectious Disease and Vaccine Research. "People were really worried that COVID-19 doesn't induce immunity, and reports about people getting re-infected reinforced these concerns, but knowing now that the average person makes a solid immune response should largely put those concerns to rest." In an earlier study, Sette and his team had used bioinformatics tools to predict which fragments of SARS-CoV-2 are capable of activating human T cells. The scientists then, in this newest research, tested whether T cells isolated from adults who had recovered from COVID-19 without major problems, recognized the predicted protein fragments, or so-called peptides, from the virus itself. The scientists pooled the peptides into two big groups: The first so-called mega-pool included peptides covering all proteins in the viral genome apart from SARS-CoV-2's "spike" protein. The second mega-pool specifically focused on the spike protein that dots the surface of the virus, since almost all of the vaccines under development right now target this coronavirus spike protein. "We specifically chose to study people who had a normal disease course and didn't require hospitalization to provide a solid benchmark for what a normal immune response looks like, since the virus can do some very unusual things in some people," says Sette. The researchers found that all COVID-19 patients had a solid CD4, or "helper", T cell response, which helps antibody production. Almost all patients had produced virus-specific CD8, or "killer", T cells, which eliminate virus-infected cells. "Our data show that the virus induces what you would expect from a typical, successful antiviral response," says Crotty. And, although these results don't preclude that the immune response to SARS-CoV-2 may be detrimental, they provide an important baseline against which individuals' immune responses can be compared; or, as Sette likes to put it, "if you can get a picture of something, you can discuss whether you like it or not but if there's no picture there's nothing to discuss." "We have a solid starting foundation to now ask whether there's a difference in the type of immune response in people who have severe outcomes and require hospitalization versus people who can recover at home or are even asymptomatic," adds Sette. "But not only that, we now have an important tool to determine whether the immune response in people who have received an experimental vaccine resembles what you would expect to see in a protective immune response to COVID-19, as opposed to an insufficient or detrimental response." The teams also looked at the T cell response in blood samples that had been collected between 2015 and 2018, before SARS-CoV-2 started circulating. Many of these individuals had significant T cell reactivity against SARS-CoV-2, although they had never been exposed to SARS-CoV-2. But everybody has almost certainly seen at least three of the four common cold coronaviruses, which could explain the observed crossreactivity. It is still unclear, though, whether the observed crossreactivity provides at least some level of preexisting immunity to SARS-CoV-2 and therefore could explain why some people or geographical locations are hit harder by COVID-19. ¬¬"Given the severity of the ongoing COVID-19 pandemic, any degree of cross-reactive coronavirus immunity could have a very substantial impact on the overall course of the pandemic and is a key detail to consider for epidemiologists as they try to scope out how severely COVID-19 will affect communities in the coming months," says Crotty. ### The work was funded by the NIH NIAID (AI142742, AI135078, AI007036, AI00738475N9301900065, and U19 AI118626), the Bill and Melinda Gates Foundation, the Johnathan and Mary Tu Foundation and internal LJI institutional funds. Full citation: Alba Grifoni, Daniela Weiskopf, Sydney I. Ramirez, Jose Mateus, Jennifer M. Dan, Carolyn Rydyznski Moderbacher, Stephen A. Rawlings, Aaron Sutherland, Lakshmanane Premkumar, Ramesh S. Jadi, Daniel Marrama, Aravinda M. de Silva, April Frazier, Aaron Carlin, Jason A. Greenbaum, Bjoern Peters, Florian Krammer, Davey M. Smith, Shane Crotty, Alessandro Sette. Targets of T cell responses to SARS-CoV-2 coronavirus in humans with COVID-19 disease and unexposed individuals. Cell, 2020. Doi: https://doi.org/10.1016/j.cell.2020.05.015 About La Jolla Institute for Immunology The La Jolla Institute for Immunology is dedicated to understanding the intricacies and power of the immune system so that we may apply that knowledge to promote human health and prevent a wide range of diseases. Since its founding in 1988 as an independent, nonprofit research organization, the Institute has made numerous advances leading toward its goal: life without disease.
If its good news for a vaccine because we build immunity when exposed... Its very good news for prospects of herd immunity. Now there are still some questions... but they impact both vaccine and natural herd immunity. Like how long will it last. However, unless you think we will have a vaccine soon... this article is looking even better, so I will post it again. Sweden’s Coronavirus Strategy Will Soon Be the World’s Herd Immunity Is the Only Realistic Option—the Question Is How to Get There Safely China placed 50 million people under quarantine in Hubei Province in January. Since then, many liberal democracies have taken aggressive authoritarian measures of their own to fight the novel coronavirus. By mid-March, almost all Organization for Economic Cooperation and Development (OECD) countries had implemented some combination of school, university, workplace, and public transportation closures; restrictions on public events; and limits on domestic and international travel. One country, however, stands out as an exception in the West. Rather than declare a lockdown or a state of emergency, Sweden asked its citizens to practice social distancing on a mostly voluntary basis. Swedish authorities imposed some restrictions designed to flatten the curve: no public gatherings of more than 50 people, no bar service, distance learning in high schools and universities, and so on. But they eschewed harsh controls, fines, and policing. Swedes have changed their behavior, but not as profoundly as the citizens of other Western democracies. Many restaurants remain open, although they are lightly trafficked; young children are still in school. And in contrast to neighboring Norway (and some Asian countries), Sweden has not introduced location-tracing technologies or apps, thus avoiding threats to privacy and personal autonomy. Swedish authorities have not officially declared a goal of reaching herd immunity, which most scientists believe is achieved when more than 60 percent of the population has had the virus. But augmenting immunity is no doubt part of the government’s broader strategy—or at least a likely consequence of keeping schools, restaurants, and most businesses open. Anders Tegnell, the chief epidemiologist at Sweden’s Public Health Agency, has projected that the city of Stockholm could reach herd immunity as early as this month. Based on updated behavioral assumptions (social-distancing norms are changing how Swedes behave), the Stockholm University mathematician Tom Britton has calculated that 40 percent immunity in the capital could be enough to stop the virus’s spread there and that this could happen by mid-June. Stay informed In-depth analysis delivered weekly Sweden has won praise in some quarters for preserving at least some semblance of economic normalcy and keeping its per capita death rate lower than those of Belgium, France, Italy, the Netherlands, Spain, and the United Kingdom. But it has come in for criticism in other quarters for exceeding the per capita death rates of other Nordic countries and in particular, for failing to protect its elderly and immigrant populations. People receiving nursing and elder-care services account for upward of 50 percent of COVID-19 deaths in Sweden, according to Tegnell, in part because many facilities were grievously slow to implement basic protective measures such as mask wearing. Immigrants have also suffered disproportionately, mainly because they are poorer on average and tend to work in the service sector, where working remotely is usually impossible. But Swedish authorities have argued that the country’s higher death rate will appear comparatively lower in hindsight. Efforts to contain the virus are doomed to fail in many countries, and a large percentage of people will be infected in the end. When much of the world experiences a deadly second wave, Sweden will have the worst of the pandemic behind it. When much of the world experiences a deadly second wave, Sweden will have the worst of the pandemic behind it. Sweden’s response has not been perfect, but it has succeeded in bolstering immunity among the young and the healthy—those at the lowest risk of serious complications from COVID-19—while also flattening the curve. The country’s intensive care units have not been overrun, and hospital staffs, although under strain, have at least not had to juggle additional childcare responsibilities because daycares and lower schools continue to operate. Whether or not they have openly embraced the Swedish approach, many other countries are now trying to emulate aspects of it. Both Denmark and Finland have reopened schools for young children. Germany is allowing small shops to reopen. Italy will soon reopen parks, and France has a plan to allow some nonessential businesses to reopen, including farmers’ markets and small museums, as well as schools and daycare centers. In the United States, which has by far the highest absolute number of reported COVID-19 deaths, several states are easing restrictions at the urging of President Donald Trump, who despite bashing the Swedish model, is pushing the country toward something very similar. There are good reasons for countries to begin easing their restrictions. It will take several years to tally the total number of deaths, bankruptcies, layoffs, suicides, mental health problems, losses to GDP and investments, and other costs attributable not just to the virus but to the measures used to fight it. It should already be obvious, however, that the economic and social costs of lockdowns are enormous: estimates from the OECD suggest that every month of pandemic-related restrictions will shrink the economies of advanced countries by two percent. France, Germany, Italy, Spain, the United Kingdom, and the United States, according to the OECD, will see their economies shrink by more than 25 percent within a year. Unemployment is rising to levels unheard of since the 1930s—fueling political backlash and deepening social divisions. Lockdowns are simply not sustainable for the amount of time that it will likely take to develop a vaccine. Lockdowns are simply not sustainable for the amount of time that it will likely take to develop a vaccine. Letting up will reduce economic, social, and political pressures. It may also allow populations to build an immunity that will end up being the least bad way of fighting COVID-19 in the long run. Much about the disease remains poorly understood, but countries that are locked down now could very well face new and even more severe outbreaks down the road. If these countries follow the Swedish path to herd immunity, the total cost of the pandemic will decrease, and it will likely end sooner. Sweden’s approach to COVID-19 reflects the country’s distinctive culture, and aspects of it may not be easy to replicate elsewhere. In particular, reliance on official recommendations and individual responsibility may not travel well beyond Scandinavia. Sweden is a special country characterized by high levels of trust—not just between people but between people and government institutions. Swedes were primed to take voluntary recommendations seriously in a way that citizens of other nations may not be. Swedes are also generally healthier than citizens of many other countries, so additional precautions may be necessary to protect the infirm in other parts of the world. Countries lifting restrictions should also learn from Sweden’s missteps when it comes to the elderly and immigrants: masks and other protective equipment should be made immediately available in nursing homes, and greater emphasis should be placed on protecting service-sector workers who are at higher risk because of age or infirmity. But the emphasis must be on helping at-risk people stay safe and out of harm’s way, not locking entire societies down. As scientists learn more about the virus and authorities develop new and better ways to work around the contagion—altering the parameters for calculating herd immunity to account for behavioral changes, for instance—the justification for general lockdowns grows weaker and weaker. Even in places like the United States and the United Kingdom, where the pool of at-risk people is much larger, the cost of protecting these people is much lower than forcing everyone to stay home. Managing the path to herd immunity means, above all, protecting the vulnerable. Sweden learned that the hard way, but the situation there is now under control. As the pain of national lockdowns grows intolerable and countries realize that managing—rather than defeating—the pandemic is the only realistic option, more and more of them will begin to open up. Smart social distancing to keep health-care systems from being overwhelmed, improved therapies for the afflicted, and better protections for at-risk groups can help reduce the human toll. But at the end of the day, increased—and ultimately, herd—immunity may be the only viable defense against the disease, so long as vulnerable groups are protected along the way. Whatever marks Sweden deserves for managing the pandemic, other nations are beginning to see that it is ahead of the curve. NILS KARLSON is Professor of Political Science at Linköping University and President and CEO of the Ratio Institute. CHARLOTTA STERN is Professor of Sociology in Work and Organization at Stockholm University and Deputy CEO of the Ratio Institute. DANIEL B. KLEIN is Professor of Economics and JIN Chair at the Mercatus Center at George Mason University and Associate Fellow of the Ratio Institute. https://www.foreignaffairs.com/arti...dens-coronavirus-strategy-will-soon-be-worlds
I want to thank smallfil for posting this on another thread. This is one more link in the chain of evidence that the fear and doom crowd is pushing a false narrative as hard as the can. Everyday we see a new fear headline about Sweden failing and almost everyday they reveal nothing new. And yet almost everyday the deaths in Sweden go down. I predict new cases will go up in Sweden but few if any articles will explain their increase in testing. Also compliments to the people who were explaining that when you have that many people a carrier a few of them may be feeling sick again. It does mean they have reacquired Covid. Yet the doomers were using this as part of that narrative. Logic is not the doomer's forte. -- More BS on the USS Theodore Roosevelt so called re-infections. Those so called Corona Virus cells are dead cells. Now, it is the navy saying it now and those test kits they are using giving positive readings only because it is designed to see if there are Corona Virus cells in your body. Doesn't matter if they are dead or alive. So, extreme liberal media promoting the re-infection angle to promote the continued shutdowns? Yet, there are no re-infections at all? https://www.yahoo.com/news/recovere...ons-about-coronavirus-immunity-170104312.html
https://www.npr.org/sections/goatsa...ce-recovered-covid-patients-can-infect-others Health officials there studied 285 patients who tested negative for the virus after recovering, but weeks later tested positive again. The question — in this and similar situations — is whether a positive test in this circumstance means that these people can still spread the virus. To find out, the scientists followed up with nearly 800 of those people's personal contacts, such as family members. They found no evidence that they had contracted the virus from the people who had a fresh positive result. The scientists also tried to grow the virus in secretions from these patients. They could not. As a result of these findings, published online Tuesday, the South Korean CDC no longer recommends that people in this situation be isolated. Their contacts do not need to be quarantined, though health officials do plan to continue investigating cases of people who have tested positive again after having had a negative test. The study is shedding some light on the natural course of COVID-19. It's providing hints, but not definitive information, about how to handle patients who continue to test positive for the coronavirus long after their symptoms have resolved. The persistence of the virus in some people "seems to be a normal thing that happens," says Dr. Aaron Hess, an anesthesiologist at the University of Wisconsin School of Medicine and Public Health. He and his colleagues encountered this conundrum as well. They were testing patients who had recovered from a bout of COVID-19 and had offered to donate blood plasma to use as part of an experimental treatment. The researchers tested a group of patients at least two weeks after they had recovered, just to make sure they weren't still producing virus. Eleven patients, representing 13% of their sample, still tested positive, "and this was a little surprising," he said. The test, known as PCR (for polymerase chain reaction), looks for genetic material from the virus. Both in the case of the Wisconsin study and that from South Korea, the level of genetic material from the virus in the sample was very low, Hess notes. That's consistent with the idea that it's simply biological residue, not signs of an active viral infection. "Having a positive PCR test after you've recovered in no way implies that you're infectious," Hess says. But it's still not clear when a positive result is worry-free.
This is likely the answer to which many of us have been wondering. Given the professed qualities of Covid...why are we not all exposed? Why did people at places like Costco and first responders not get hammered outside of a few clusters. There is no way this virus spreads like the doomers claim. We would all have been destroyed quickly by something that remains hidden in over 50 percent of the infected for up to 14 days who are asymptomatic. There is no way a disease with a R0 of 4 (or even 2) would have stayed contained before the shutdown. There is no way Sweden's deaths could be trending down like they are now. The answer... based on that math in this study below. Clusters and Superspreader... and most others hardly spread it at all. And sadly SOBs like Fauci should have or did know this theory of Superspreads and virus.... This is why weeks ago when asked about testing and tracing the Head of German Covid Response said testing and tracing may need only be done where there are pockets of outbreaks.(even though doomers here like GWB keep pushing testing and tracing.) (there is a link For now we know... there is no shared scientific reason to keep the low risk groups from working. We can probably keep the virus well under control with just letting the low risk group back to living and a quickly testing and tracing when a clusters form. (Pure speculation based on the fact I stayed at a holiday in express 10 years ago.) I suspect further research will show that those with compromised immune systems spread this virus at a higher rate. It might have something to do with the lungs response to the virus and/or the quality or quantity of the virus exhaled from those with compromised immune systems. Those on their way to having serious fluid in their lungs. Maybe during the pre-pneumonia or pneumonia stage. By the way... masks are most likely bullshit just like they said in the beginning. https://wellcomeopenresearch.org/articles/5-67 Results: Our model suggested a high degree of individual-level variation in the transmission of COVID-19. Within the current consensus range of R0 (2-3), the overdispersion parameter k of a negative-binomial distribution was estimated to be around 0.1 (median estimate 0.1; 95% CrI: 0.05-0.2 for R0 = 2.5), suggesting that 80% of secondary transmissions may have been caused by a small fraction of infectious individuals (~10%). A joint estimation yielded likely ranges for R0 and k (95% CrIs: R0 1.4-12; k 0.04-0.2); however, the upper bound of R0 was not well informed by the model and data, which did not notably differ from that of the prior distribution. Conclusions: Our finding of a highly-overdispersed offspring distribution highlights a potential benefit to focusing intervention efforts on superspreading. As most infected individuals do not contribute to the expansion of an epidemic, the effective reproduction number could be drastically reduced by preventing relatively rare superspreading events.