Here at Project Contact our response to COVID-19 is Contact, a system designed to aid epidemiologists conduct customized contact tracing, identify emerging hotspots, and notify individuals they have been in contact with an infected person and may have become infected too.

This web site is intended primarily for epidemiologists, biostatisticians, contact tracers and public health officials seeking high quality tools for contact tracing, but all are welcome. It is also an informational web site for curious member of the general public who want to learn more about Covid-19, virus testing, infectious disease outbreak control, and attendant privacy concerns.

Project Contact has designed and is implementing contact tracing tools based on cell phone technologies to assist with traditional contact tracing and also to push the boundaries and advance the state of the art in infectious disease monitoring and containment.

100% Privacy and Anonymity

Using cell phone technology for contact tracing raises important and challenging privacy issues. Rather than ignoring or skirting those important concerns, we have made them central to our mission, which is to ensure—with 100% certainty—individual privacy and anonymity for all users. The Contact system will not allow any company, organization or government to discover the identity of any user of the Contact system unless and until a user explicitly chooses to share personally identifiable information. Even we, at Project Contact, cannot identify any of our users unless they choose to be identified.

All visitors, whether scientists, epidemiologists, public health officials, or just ordinary citizens should be deeply concerned about ensuring the privacy of their personal information given the nature of contact tracing.

There Cannot Be Trust Without Privacy

Effective contact tracing relies on strong cooperation from and with the index case. Gaining that cooperation depends on creating a trusting relationship and honest, clear, and complete privacy guarantees are often essential to building trust. Introducing technology into contact tracing cannot eliminate the need for trust.

In democratic societies, governments cannot force citizens to submit to the tracking of their locations and contacts. For app-based contact tracing to be useful and effective, wide user adoption is essential, and people must choose to participate. Few will do so unless they are quite certain they can control and maintain their privacy.

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Image of COVID-19 virus
Electron microscope image of 2019-nCoV (provisional name for SARS-CoV-2)

Are You an Epidemiologist?

If you are an epidemiologist interested in contact tracing and guiding the future practice of digital contact tracing from the outset, please know that we seek an expert advisor (or two) and contact us.

Please Consider Joining Our Working Group

The CDC has recognized the arrival of Digital Contact Tracing Tools for COVID-19 and offers evaluation criteria

If you are an expert in epidemiology/biostatistics, public health policy, privacy law, data security, or medical privacy ethics, please consider contacting us about joining our developing Working Group on Digital Contact Tracing Functionality and Privacy.

The development and application of digital tools for contact tracing is a new frontier. Leaving it to tech companies is irresponsible given their history of disregard for privacy and demonstrated inability to secure data.

It's too Late to Rush in Some Directions

During the first week of January (2020) the World Health Organization (WH0) began reporting a disease outbreak, a pneumonia of unknown cause, in Wuhan, China. A week later, China shared the genetic sequence of the new and novel coronavirus (2019-nCoV), and the first case outside of China (in Thailand) was reported. The following week, WHO reported evidence of human-to-human transmission in Wuhan.

On January 30, WHO issued a situation report indicating a total of 7,818 confirmed cases with 82 outside of China in 17 other countries. They rated the public health risk to China as Very High, and the risk to every other country as High and issued preparedness and response guidelines.

That was the time for a rapid, aggressive containment response around the world. Few countries responded tangibly and the virus spread rapidly around the world. Three months later, globally, there are over 3 million confirmed cases of COVID-19 and 230,000 deaths. Unfortunately, testing for COVID-19 is so far behind the need for testing—in almost all countries—that the number of confirmed cases is certainly a small fraction of the actual number of infections.

Where to Rush Now

Countries around the world, especially the rich nations, should have rushed to action in February to avoid a pandemic. That opportunity passed. Now, countries around the world must pursue treatment and aggressive containment, both of which require widespread availability of rapid and accurate testing. Poor countries (and regions) will require a lot of help, which is not likely to be forthcoming as most rich nations themselves are far from meeting their own testing needs.

Medical experts, clinicians, and researchers must work as quickly as practical to develop effective treatments for COVID-19, while others work on pharmaceutical interventions while and effective vaccines.

Where Not to Rush Now

At Project Contact we believe there is a place for digital contact tracing, and we seek to offer best-in-class tools for that purpose. However, public health investigators (PHIs) have been conducting contact tracing for decades, without digital technologies, using well-developed, reliable protocols and practices which have proven highly effective over time.

Digital contact tracing raises widely recognized user privacy concerns which must be carefully, publicly and thoroughly addressed before rolling out new tools. A central requirement of effective contact tracing is a trusting relationship between index cases and PHIs. Prematurely adopting digital contact tracing tools that ultimately violate user privacy will destroy the future of digital contact tracing and might become a major setback to index case participation in traditional contact tracing too.

App Face

The public facing side of Contact is an app for everyone. The more downloads the better. The app captures a combination of location information (via GPS) and contact information (via Bluetooth).

A contact occurs when two phones come into close proximity for more than a threshold period of time.

The Contact app will take full advantage of the new Bluetooth support that Apple and Google are preparing for iOS and Android phones which they announced will become available in May. This new functionality is specifically intended by Google and Apple to facilitate contact tracing.

While Apple and Google stop at Bluetooth for contact tracing, Contact goes further. Contact also makes use of location data (GPS) to help public health investigators (PHIs) understand geographical spread and infection density too.

The Contact app, like all parts of the Contact system, is designed to ensure 100% privacy for all users.


EpiServer ties the Contact system together, it:
  • manages the apps
  • processes data requests from epidemiologists, contact tracers, and other public health users
  • performs epidemiologist-directed app tuning

How Many Contact Investigators?

The Johns Hopkins Center for Health Security and the Association of State and Territorial Health Officials (ASTHO) estimates that the U.S. will need at least 100,000 contact investigators for COVID-19.

Are You a Public Health Investigator?

Please let us know if you have questions, comments, or want to participate as an advisor or user.

Epi Face

The public health facing side of the App provides a browser-based interface to the Contact system through which epidemiologists, biostatisticians, contact tracers, and other public health workers and researchers—public health investigators (PHIs)—obtain data about the geographical distribution, transmission, and person-to-person contact of an active, infectious disease.

Contact lets PHIs sift data in many ways, including,
  • index case direct contacts
  • index case indirect contacts
  • contact trace by level of contact
  • infection density by geographic region
  • rate of spread by geographic region
  • social distancing behavior by region

and more.

Contact is not intended to replace human PHIs—no software can. Rather, it is a set of tools to amplify the efforts and effectiveness of public health investigators.

What Is Data Rustling?

The standard trade-off in the cell phone world of mobile apps is for companies to provide apps for no money. "No money," does not mean free—nothing is. There is an exchange of software for private, individually identifiable, personal data.

App producers—almost all—design their apps to rifle though every data corner of the phone and take all they want: phone contacts, e-mail addresses, photographs, documents, phone call records, lists of installed apps, etc. Apps may also eavesdrop on phone calls and ambient conversations.

Apps may also subject the user to unsolicited advertising, GPS tracking, notifications, e-mail, text messages, etc. For good measure, after they rustle user data, it becomes theirs, and they frequently sell it to anyone willing to pay almost anything at all for it. We, at Project Contact, have coined a term for this behavior. We call it data rustling.

Uninformed Consent

Users give their implicit consent to become victims of data rustling with each app download. Users are not told that data will be rustled, which data will be rustled, what will be done with the rustled data, with whom the rustled data will be shared, or anything else about the plans or practices of the data rustlers. App users are left completely uninformed about the data rustling activities of the apps they download.

If users are perfectly comfortable giving away their data in exchange for use of an app, what’s the problem? The problem is that the data useful for contact tracing is a very comprehensive log of the historical locations of the user’s phone, and also a partial log of every other phone which has been in close proximity. If the contact data from many phones is combined (all app providers hope to combine their rustled data), the result is a movement/interaction map of citizenry—a surveillance system—on a scale and at a level of detail never seen before.

Trust the Company or the State?

The companies producing all of these data rustling apps have put forth an argument that the public has generally accepted. They argue that it’s better to trust your data in the hands of private, for-profit companies than in the hands of a government. In essence, the argument is that private companies want your data to provide targeted advertising and, although that might be a bit annoying, unlike the government, a private company cannot arrest you and deprive you of your freedom. There is some truth to that argument and early on that argument was more compelling. Today there is another dimension to consider.

It is true that private companies do not have authority to arrest and imprison. However, it is no longer true that all they can do with user data is harmlessly sell advertising. The evidence is overwhelming that the 2016 U.S. presidential election was ultimately tipped in the direction of its outcome by Facebook’s market for user data. The consequences of the uses of rustled data are no longer wholly innocuous. Today, it is reckless to place enormous troves of what ought to be private, user data into the hands of private companies.

At the same time, imagine how a more or less perfectly complete trace of everyone’s physical location across time, along with a complete record or every person-to-person contact might be used and abused by governments. Access to such data allows detection of jaywalking, speeding and other traffic violations, parole and restraining order violations. It could be used to identify and monitor group affiliations, labor organizing efforts, and demonstrators. It could reveal medical conditions and vices of many varieties. Once in the hands of government, it is hard to imagine how its access can be reliably and transparently controlled. So, the key to contact tracing with privacy is not to place the data into the hands of private companies and not place the data into the hands of government.

Collected Data Cannot Be Shielded From Abuse

We at Project Contact believe that even if app users are willing to give up their data and anonymity, it is a terrible mistake, and we are unwilling to help them do so. Fortunately, though it may seem impossible to use apps to assist in contact tracing and also ensure that users have complete control of their privacy, it is possible. That is what the Contact system does.

Companies, no matter their slogans, promises, court settlements, and consent decrees cannot be trusted with private data. They are motivated only by profits in an age where data is the new currency. For many companies, information is their most valuable asset, and data rustling is how they obtain it. Review the list of irresponsible companies (to the right). Most of them produce no physical product; they are pure data companies. They exist to capture, aggregate, organize, massage, and sell data including the identities of the individuals the data describe.

Governments around the world, at times, violate the privacy of their citizens. In authoritarian states they do so with impunity. In democratic ones they hide their efforts, so we only learn of governmental privacy violations when they get caught.

Trust Only in Anonymity

If app users allow any personally identifiable information (PII) to be shared or rustled by any contact tracing app they lose their anonymity.

Beyond that, even if the contact tracing app doesn't send any PII, it may be instrumental in revealing a user's identity. For example, in addition to all the communicating your phone is doing without your knowledge (see app trackers), every time your iPhone checks for e-mail, sends a text message, visits iTunes, or uses any other Apple service, your iPhone must send a request to an Apple server. All data on the Internet moves in bundles called packets. Each packet includes the unique Internet Protocol (IP) address of the server to which the data is being sent, and also the unique IP address of the sender (so the server can respond). The IP addresses are always part of the packet since, without them, the packet cannot be delivered to the server and a response cannot be returned.

So, even if your contact tracing app is not sending any PII to Apple's server, it's still sending your IP address. It is a simple matter to match up the IP address from the contact tracing data with the IP address from, say, an e-mail request. Then, since the user's IP address accompanying the anonymous contact trace data is the same as the IP address accompanying the non-anonymous e-mail request, the two users must also be the same and—poof!—the user's anonymity is gone.

Of course, the same is true for Google, Facebook, Samsung and everyone else. If you think you can send them anonymous, PII-free data, and also use any of their services—intentionally or unknowingly—and also remain anonymous, well, you've got another think coming.

Project Contact Can Do It

Relying on the very companies that pioneered data rustling (and earn billions practicing it) to protect privacy is like hiring a fox to guard chickens. Even if the fox promises he will guard the chickens, and means it too, who would believe he can overcome his nature?

Project Contact has developed an approach to maintaining absolute anonymity and privacy. Such protection is not possible without placing some constraints on the functionality of the contact tracing tools. We observe that many of the emerging digital contact tracing tools are intended to replace skilled, human, contact tracers with an app. We know that's not possible. Our goal is to provide tools to assist and speed contact tracing and epidemiological analysis, but never at the expense of privacy.

Please contact us to learn more.

Who do You Trust?

Facebook: In 2019, Facebook was fined $5 billion by the Federal Trade Commission for user privacy violations

Apple: In 2019 Apple was sued over Siri's surreptitous and unauthorized recordings of iPhone users. Also, in the same year, Apple was sued for selling users' iTunes listening data

Twitter: got caught misusing customer data in 2018

Google and YouTube: In 2019, Google and YouTube were fined $170 million for violating the Children's Online Privacy Protection Act

Facebook, WhatsApp, Apple, Twitter, LinkedIn: In 2019, various EU countries opened numerous investigations into Facebook, WhatsApp, Twitter, Apple and LinkedIn for violating the European Union's General Data Protection Regulation (GDPR).

Android: Google's Android operating system uses a least privilege security system which lets apps ask the user for needed permissions to access sensitive information like GPS location, the phone's serial number (IMEI), access the camera, read data files etc. Researchers discovered that many apps (over 1,300), including popular ones, are able to circumvent Android's security system and gain access even when the user has expressly forbidden such access. The photo-editing app, Shutterfly, for example, extracts GPS coordinates from photos on the phone and sends that data to its own servers, even when users deny the app permission to access location data. The researchers actually witnessed and monitored the data transfer. An article on reports that a spokeswoman for Shutterfly insists the company would only gather location data with explicit permission, despite what the researchers found.

App Trackers: A story by The Washington Post into the regular, voluminous transfer of data from his iPhone, night after night, revealed that in spite of Apple's claim that, “What happens on your iPhone stays on your iPhone,” there were 5,400 hidden app trackers, mostly in apps on his phone, sending 1.5 gigabytes of personally identifiable information to, among others, Citizen, Intuit, Microsoft, Nike, The Washington Post, Weather Channel and Yelp. While Apple, with an iron fist, imposes complete and absolute control over which apps can be installed on their phones (you get to pay for them, while Apple actually owns them) and what features each app can access. Apple is fully aware of this situation and takes no steps to constain this data rustling.

FBI: According to a report by the Brennan Center For Justice, the FBI violated the Fourth Amendment privacy rights of tens of thousands of Americans by searching e-mails without a warrant over a period of eight years, beginning around 2008.

None of the above can possibly happen by accident or by the hand of a lone, bad actor. It requires scheming and premeditation, invariably at a high level, and then implemention, testing and deployment by a team technical experts. All participants, from the senior executives, to the sales and marketing team planing to sell the data, to the technical team, all know exactly which lines they are crossing. Punishment, beyond easily absorbed fines, never occurs so the behavior has become endemic among data rustling tech companies.

Where Is Your Personal Data Safe?

In addition to intentional privacy breaches, financial institutions, department stores, big box stores, governmental agencies, and all other variety of organizations are negligent in their handling of even people's most sensitive and private data. They are routinely hacked and enormous troves of personally identifiable information are captured. The companies and organizations from which the data are rustled are routinely found to have been negligent in their data security practices, as expressed in sometimes significant fines. Here is a very brief but representative list:

  • Wells Fargo Bank $3 billion settlement (2020)
  • Equifax $575 million (2017)
  • British Airways $230 million (2019)
  • Marriott International $124 million (2019)
  • Uber $148 million (2016)
  • Yahoo $85 million (2013)
  • Target $18.5 million (2017)
  • Anthem $16 million (2018)
  • Google $7.5 million (2020)
  • University of Texas MD Anderson Cancer Center $4.3 million (2018)

Note, the Wells Fargo "data breach" was completely internal. Wells Fargo, from 2002 - 2016 opened approximately 3.5 million unauthorized, fraudulent accounts on behalf of their customers in order to bill them for products and services they did not request or want.

The vast majority of data breaches go undetected or unreported.

All that follows is basic, background information about COVID-19, and infectious disease control.

The currently raging COVID-19 pandemic caught much of the world, including the U.S., off-guard and unprepared. In some places the virus seems to be coming under control, but rural areas are being infected later and more than two billion people in countries and areas with the most limited public health resources remain at grave risk as this pandemic appears poised to take a terrible toll. Even in countries with relative good public health systems the mortality rate appears to be 1% - 2%.

Some Definitions

pathogen: a bacterium, virus, or other microorganism that can cause a disease
antigen: a molecule or molecular structure which triggers an immune response
antibody: proteins made by white blood cells in response to an antigen that has triggered an immune response. Each antibody can bind to only one specific antigen, and binds to help destroy the antigen.
coronavirus: a large group of viruses known to affect birds and mammals and named for the spiky antigens projecting from their surfaces that resemble the points on a crown (corona is the Latin word for crown)
2019-nCoV: initial, provisional name given by virologists to the virus that causes COVID-19 illness
SARS-CoV-2: final name given by virologists to the virus after considering how it is related to similar viruses
COVID-19: the name of the disease caused by the SARS-CoV-2 virus

Highly contagious infectious diseases, especially ones which frequently cause serious illness or death, that are ultimately contained—sometimes even eliminated from our planet—are contained by effective vaccines. It seems likely that one or more effective vaccines for COVID-19 can be developed, and virologists are working at record speed to develop them. However, it seems unlikely any effective vaccines will be developed and tested for safety before late 2021 or 2022. It is likely to take two to five or more additional years to produce enough vaccine for eight billion people. Keep in mind, too, that no vaccine has ever been developed for a virus similar to COVID-19. In the best case, while vaccines are under development effective pharmaceutical treatments will arrive.

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Boys wearing camphor bags to ward off Spanish flu
Boys warding off Spanish flu with camphor necklaces (1918)
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Paramedics transporting 1st coronavirus patient (January 2020)
Paramedics transporting a man believed to be Hong Kong's first coronavirus patient (January 2020). Lam Yik Fei for The New York Times

The Risk of Doing Nothing

Proceeding without any containment efforts, keeping schools and businesses open, gathering in stadiums, theaters, group meetings and social events will certainly bring the swiftest possible end to the pandemic. In that case, most everyone gets quickly exposed to the virus and those whose bodies succeed in fighting off the virus live and the rest don’t. That’s exactly what happened during the Spanish flu pandemic. It began in January 1918, and “burned out” in 1919, as it ran out of previously uninfected hosts.

There was no decision made during that time to let the virus go unchecked. Rather, its nature was not understood. Initially, the medical community thought the pathogen was bacterial. No effective pharmaceutical interventions were available or developed and worldwide it is reported by the CDC that 500 million people (one-third of the world’s population) became infected and 50 ‐ 100 million died (675,000 in the U.S.).

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Graves of COVID-19 victims, cemetery in Manaus, Brazil
Cemetary for COVID-19 victims, Manaus, Brazil

How Contagious: R0 (“R-naught”)

The intensity of an outbreak of an infectious disease, or its degree of contagion, boils down to the rate of transmission from each infected person to uninfected ones. This is captured by epidemiologists in the basic reproduction number (or basic reproductive ratio) R0. If, on average, each infected person infects one other person then R0 = 1. If each infected person spreads the infection to 2 people, R0 is 2, etc.

When R0 > 1 the overall number of infections must be on the rise. If R0 is less than 1 infections are declining. For context, seasonal flu has R0 = 1.1 (approximately). Measles, one of the most contagious of all diseases, has 12 < R0 < 18 (between 12 and 18). It appears that R0 for COVID-19 is 2 – 2.5, similar to Spanish flu.

However, R0 is not fixed at one value in all places over time. It will likely be higher in places where lots of people come in close contact for extended periods, like factories, cruise liners, naval ships and large, densely populated cities than in sparsely populated and isolated areas. Social distancing is one way to reduce R0 by making it harder for the virus to spread, as if the population density and level of close human interaction were lower. Effective quarantining of infected people also puts downward pressure on R0.

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negative pressure isolation ward
Negative-pressure COVID-19 isolation ward, Jinyintan Hospital, Wuhan, China

How Deadly?

The level of contagion (R0) and the seriousness of the disease are two different matters. COVID-19 and Spanish flu seem to be similarly contagious with R0 ≈ 2, but about 5 to 10 times as many of those who contracted Spanish flu died from it as compared to COVID-19.

Some infectious diseases, like Chickenpox, are highly contagious (10 < R0 < 12), but are so benign (during childhood) that parents are encouraged to send their kids to school to infect as many other children as possible. The goal being for everyone to become infected as a child, thereby developing lifelong (usually) immunity, so nobody gets infected as an adult, when it is a more serious illness.

While a pandemic is still unfolding mortality rates are uncertain. The currently available data (mid-April, 2020) generally comes in two forms:

  • deaths rate among confirmed case
  • deaths per 100k (or 1 million) of population

Both need to be treated carefully. Deaths are hard to overlook and most everywhere they get recorded and classified. A patient testing positive for COVID-19 who is admitted to a hospital and dies under treatment will surely be recorded as a death due to COVID-19. A person infected with COVID-19 but undiagnosed, especially one who dies at home without treatment, will likely be recorded as a death, but it may not be attributed to COVID-19. Many cities, including New York City, keep track of daily "deaths at home." The number of such deaths in New York rose from 25 per day to 250 during its tragic outbreak. It is impossible to say what portion of those were from COVID-19, but it's likely a significant portion were. Eventually, New York adjusted its estimate of COVID-19 deaths to include some portion of those who died at home.

Even if it could be known exactly how many people died of COVID-19, death rates must be considered carefully. Suppose, somehow, it can be known with certainty that 10,000 people died of COVID-19. The value for, "deaths among confirmed cases," will depend on the number of tests administered. If those 10,000 people all tested positive then the death rate would be 100%. If 10 million positive tests occurred, the death rate would be .1%. It is impossible to separate the death rate among confirmed cases from the level of testing.

Deaths per 100k of population disentangles the rate of death from the scale of testing. However, it depends on the accuracy with which COVID-19 deaths are attributed to COVID-19. Countries with well-resourced public health systems are likely to do a better job of classifying deaths than less well-resourced ones. In India, for example, there are 1.3 billion people and 2/3 are living in poverty. Testing started slowly and peaked at just over 30,000 tests per day in mid-April, at which time the quality of the test came under question and interrupted testing efforts.

Johns Hopkins University's Systems Science and Engineering department has created a COVID-19 Dashboard to explore COVID-19 tests, deaths, recoveries, day-by-day, over time, etc. It is simply brilliant!

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Transmission Electron Microscope (TEM) image, colorized, of 2019-nCoV-2 emerging from surface of cultured cells. From NIAID RML lab in Hamilton MT
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COVID-19 virus particles
TEM image of SARS-CoV-2 virus particles. NIAID Integrated Research Facility, Fort Detrick, MD

Herd Immunity

When a large percentage (60%) of a population is immune to a disease, even a highly contagious one, it cannot spread easily because infections can only spread among uninfected members of a population who are not immune. Immunity can occur through vaccination or, for many diseases, when a person’s immune system successfully overcomes the infection. Achieving herd immunity by widespread use of safe and effective vaccines is a safe path to herd immunity. Attempting to achieve herd immunity by intentionally letting a highly contagious, infectious disease spread across the world and simply hope it doesn’t kill too many people is mighty risky. When a highly contagious disease is known to have even a high mortality rate, as COVID-19, such an approach is generally considered unconscionable.

Click to enlarge COVID-19 virus
'Spikes' are its immunodominant antigen of SARS-CoV-2

The Swedish Experiment

Sweden chose to pursue a direct path to herd immunity for COVID-19 instead of containment. Their intention was to try and isolate the elderly, as they are most susceptible to COVID-19, but impose only very modest restrictions on public life. Sweden’s neighbors, Finland and Norway, closed schools and restaurants and other businesses, etc. Sweden encouraged people to work at home if possible and banned gatherings of 50 people or more, but did not close restaurants, bars, businesses or schools, leaving all but the elderly free to infect each other. If they are successful in achieving herd immunity relatively quickly, without a significant overall increase in mortality (i.e. deaths per million people), they will have avoided the economic catastrophe besetting countries adopting and enforcing stringent social distancing practices.

The Swedish experiment is still underway. So far (mid-April, 2020), per capita COVID-19 deaths in Sweden are twice as high as in Denmark and four times higher than Finland. One should expect a higher rate in Sweden since infections are likely more widespread in the absence of stringent social distancing. Will Sweden’s early and higher proportion of deaths be offset by a lower rate later? Will the lower proportion of deaths in Finland and Norway, where stringent social distancing was adopted early in the pandemic, be offset by a longer period of deaths than in Sweden? We must wait and see.

The Swedish architects of their approach point out that a large portion of COVID-19 deaths were among their care homes for the elderly. That should not be a surprise as nursing homes, assisted living facilities and other places with large proportions of elderly residents, if touched by such contagion, generally experience higher death rates because COVID-19 is especially dangerous to older people and it is very difficult to protect such facilities from infection. A central element of their herd immunity plan was to protect the elderly from infection. Failing to do so cannot be ignored in evaluating the efficacy of their plan.

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Confirmed COVID-19 deaths in Sweden (
Click to enlarge Chart of Swedish COVID-19 cases per 100k by county
Swedish COVID-19 cases per 100,000 by county (

The Japanese Experiment: Cluster Infection Theory

In Japan, the national government recommended that schools close and 99% did but, beyond that, social distancing was made optional and left up to each individual. Japan, early on, reported few COVID-19 cases, but they did little testing so, naturally, few cases were diagnosed. At the end of March 2020, Japan had performed about 17,000 tests with a population of 126 million. For comparison, see chart in right column.

Of course, the volume of testing doesn't tell us anything about the accuracy of those tests, the turnaround time, or why tests were administered (to diagnose patients or to monitor spread of the pandemic).

Japan never closed businesses, bars or restaurants, or discouraged use of their legendarily crowded trains and subways. As spring emerged, while much of the world was sheltering in place, Japanese flocked by the thousands to parks, picnicking, posing for pictures, and crowding together in Japan's famed cherry blossom festivals to enjoy the magnificence of their trees in full bloom.

No efforts were undertaken to ramp up hospital readiness or testing, or flatten any infection curves by social distancing, or create and organize a national response. The plan of the Japanese leadership was to handle clusters of infection as they arose. Instead of calling this the "No Plan" plan, they call it "Cluster Infection Theory."

In the country with the highest percentage of elderly in the world, during a pandemic which most severely targets the elderly, it is not surprising that in April Japan recognized and reported a spike in infections. It seems unlikely that cluster infection theory will survive its first application.

Country Tests/Million People
Germany 11,000
Italy 9,500
South Korea 7,800
United States 3,000
Japan 135
India 40
(Data source: Our World in Data)
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Japanese cherry blossom festival
Japanese ignoring signs warning people not to gather as they celebrate Cherry Blossom festival, March, 2020


As humans have no natural immunity to COVID-19, and it is highly contagious with a significant mortality rate, and no vaccine or effective treatments are yet known, the only options are to let it run wild or attempt to contain it. Most of the world missed the chance to limit the spread of COVID-19, and eventually responded by some combination of quarantine and social distancing efforts including: closing schools and non-essential businesses, prohibiting large gatherings like sporting events and concerts and sit-down restaurants, and recommending or requiring that people shelter in place. Where this was done relatively early, R0 is beginning to decline, sometimes below one. If social distancing requirements are lifted too soon, R0 will quickly rise, we’ll return to where we were before social distancing, and all the illness, death and economic calamity already experienced will have been for nothing.

If social distancing efforts remain in place for long enough, new infections and deaths will Even so, COVID-19 will not disappear. COVID-19 appears to have been transmitted from a Horseshoe bat to a pangolin and then to a human. Once a contagious virus infects a population it does not simply disappear. All influenza A pandemics and almost all influenza A cases since 1918 are descendants of the Spanish flu virus. H1N1 (Influenza A variant, "swine flu"), H2N2 (Influenza A variant, "Asian flu") and H3N2 viruses all contain genetic material from Spanish flu.

Even the best-case scenario is that after the pandemic is brought under control, outbreaks will recur, possibly seasonally, until widespread immunity is achieved through vaccination. The first Polio (R0 > 5) outbreak, for example, appeared in the U.S. in 1843, with increasingly severe annual seasonal outbreaks recurring until vaccines were developed in the mid-1950s. It took 20 more years to wipe out polio in the U.S., and it still persists in some parts of the world. To prevent localized outbreaks from becoming pandemics two tools are needed: widely available and accurate testing and contact tracing.

Testing for COVID-19

There are three kinds of testing for COVID-19:

  • PCR (polymerase chain reaction) tests
  • antigen tests
  • antibody tests

PCR tests determine if a person is currently infected. They work by sequencing the viral DNA (or the viral RNA copied to DNA) collected on a nasal or throat swab and comparing it to known viral sequences. PCR tests are relatively fast and easy to design but, by their nature, can only be used diagnostically during acute-phase infection. These tests rely on lab techniques which are difficult to miniaturize for point-of-care use.

Antigens are physical structures on the surface (or protruding from) a virus that exactly match a physical structure on the surface of a human cell. It is this perfect fit of the antigen to the cell that allows the virus to "dock" with the cell and then invade it. It is also antigens that provoke the immune system to respond and become the point of attack to neutralize the virus. The characteristic “spikes“ protruding from the coronavirus are its immunodominant antigen.

Antigen tests also determine whether a person is currently infected. They work by testing for the presence of specific antigens (molecules on the surface of the virus). Antigen tests are generally inexpensive and easily miniaturized for point-of-care use. Home pregnancy tests are antigen tests.

Antibody tests analyze blood samples looking for the presence of antibodies the immune system produces to fight infection. Since COVID-19 is a novel virus, no humans can have had antibodies before this pandemic. Thus, the presence of any antibodies is proof of prior COVID-19 infection. Also, the immune system produces several classes of antibodies, sequentially, as it responds to an infection, so antibody testing can also indicate, to some degree, how recently a person was infected.

All of these tests must be conducted carefully and correctly for accurate results. Also, timing matters. It takes time, for example, for the immune system to create antibodies (often 9 - 30 days after symptoms disappear).

Widespread, accurate and rapid testing are necessary for containment. Without sufficiently widespread testing it’s impossible to determine the rate of transmission, where outbreaks are emerging, or how well containment efforts are working. Without accurate testing, many individuals must be tested multiple times, with false-positives leading to the waste of valuable resources, and false-negatives preventing the quarantine of infected people. Without rapid testing, suspected cases may be treated as actual cases, with the application of all attendant resources, until test results become available.

Contact Tracing

In public health, contact tracing is the process of identifying people who have come into contact with an infected person. It is traditionally done by interviewing an infected person to discover other people who might have become infected through contact while the infected person was infectious. The discovered contacts may also be interviewed to discover people they contacted too, and so on.

An individual may or may not be considered a contact according to the transmission mechanism of the infection and the nature of the interaction with the infected person. For example, hepatitis B cannot be spread by casual contact, so a person whose only interaction was to take a three hour car ride with an infected person should not be considered a contact, but a drug partner who shared a needle with the infected person should be considered a contact. On the other hand, measles is spread through coughing and sneezing and the measles virus can live, suspended in the airspace visited by an infected person, for up to two hours. It is so highly contagious that everyone in that car should be considered a contact.

Contact tracing, along with infection testing, are the two most fundamental epidemiological tools for monitoring and interrupting the spread of infectious diseases. It also provides the information necessary for making good decisions about testing, isolation and treatment. In a context like the current Covid-19 pandemic, where widespread infection is underway and testing availability is severely limited, contact tracing is vital for determining optimal application of scarce resources. The interviews and follow-up necessary for contact tracing are painstaking and time consuming. Getting in touch with a potential contact can take much or little time, and each delay in interviewing a potential contact postpones identification of that contact and further potential contacts.

Traditionally, contact tracing is performed by interviewing an infected person. Effective contact tracing is a skill that requires training, empathy, and the ability to establish the trust necessary to achieve a high level of cooperation between the patient and the contact tracer.

For purposes of the trace, the infected person is called the index case. The contact tracer tries to help the index case recall all the people she was in contact with, when, where, for how long, and the nature of the interaction. The contact tracer evaluates the information in light of the nature of the infectious disease, its transmission mechanism, etc., to decide which of those contacts have a significant possibility of having become infected and will contact those people to alert them and recommend specific actions (e.g. testing).

A central part of contact tracing is to share information with the infected person about available social and clinical supports, possibly provide resources (e.g. digital thermometer), and hand off the infected person to a care coordinator. help the index case connect with those supports, and follow up as needed get in touch with contacts.

Potentially infected people are apprised of their risk, but not provided with information which might reveal the identity of the index case. This kind of privacy protection is a central element of contact tracing and is often necessary to gain the trust and cooperation of the index case.

Contact Tracing and Testing Go Hand in Hand

Without good testing availability contact tracing is almost pointless, as identifying potentially infected people without being able to ascertain infection suggests no course of action. Without effective contact tracing, people won't know to seek help until they are already infected, symptomatic, and been spreading the infection. Taken together, effective contact tracing and accurate, widely available testing allow early detection of outbreaks before they spread widely. Without both there is no way to prevent recurring, widespread outbreaks of diseases like COVID-19.

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Girls practicing ballet in Hong Kong during SARS outbreak (2003)
Protecting children in Hong Kong from SARS (2003)
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Passengers outside Shanghai train station
Passengers outside Shanghai train station (February 9, 2020)
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Two doctors in isolation ward
Two doctors, isolation ward, Valentine's Day, Yangzhou, China (February 14, 2020)
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COVID-19 antibodies
Antibodies from COVID-19 survivor
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Indian health workers carry candles and oil lamps to show solidarity
Hospital staff in India show solidarity with COVID-19 victims and health workers
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Playground is closed
Photo by Ben Garver, Pittsfield, MA (April 2, 2020)
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Playground is closed
Pampered dogs in downtown Shanghai on February 16, 2020
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Contact tracers in Wuhan, China
Contact tracers in protective suits during a door-to-door inspection, Wuhan, China (February 17, 2020)
The News & History

April 15, 2020 From more than 100 submissions to MISSION-R six, including Project Contact, selected for support by RIoT.

April 2, 2020 Non-profit (501(c)(3)) Raleigh Internet of Things (RIoT), an initiative of the Wireless Research Center launched MISSION-R, a call for technological responses to COVID-19.

March 25, 2020 First Project Contact white paper.
Contact Us

Director Matthew A. Brenner

Phone 757-277-4330