1. The Fence: Stop Infections from Entering

It’s logical that if you don’t prevent people from coming in from heavily infected areas at the border, some will introduce the virus and cause outbreaks.

I refer to "fences" as measures to prevent the virus from crossing borders. There are three types:

• Walls: Ban travelers from infected areas.
• Quarantines: Allow entry but isolate individuals for 4 to 14 days.
• Checkpoints: Test individuals at the border.

Countries can enforce these fences based on the likelihood of infection: the higher the risk, the stronger the fence. Walls can be costly and should be used sparingly. Checkpoints are relatively inexpensive but may not catch all cases. Quarantines strike a balance—testing upon arrival and after a few days of isolation can curb most infections.

As cases decline, regions with few infections can open up to each other, forming "green bubbles" without barriers.

Critics argue that border closures are ineffective, merely delaying the inevitable. This perspective overlooks that while they might not be sufficient alone, they are essential. No country has successfully kept case numbers low without strong border measures. Ultimately, those that don’t implement them will suffer.

In contrast, the European Union’s failure over the summer stemmed from dropping defenses after a challenging spring. The majority of current cases in the EU originated from Spain. A similar pattern occurred among U.S. states.

2. Social Bubbles: Limit Social Interactions

Certain infected individuals will inevitably enter your community, and you cannot avoid this.

When they do, it’s crucial to prevent them from interacting with others. The more people stay within their social bubbles, the less likely infections will spread to others.

Measures to foster social bubbles range from less aggressive strategies like limiting crowd sizes to full lockdowns, forcing families to remain isolated.

Complete lockdowns have devastating effects, requiring everyone to stay home and halting the economy, except for essential businesses. This was justified in March when we were unaware of the virus's true scope. The lockdown would curb growth and provide governments time to devise a strategy.

However, in today’s context, if a country experiences a wave, implements a lockdown, and has months to prepare, yet faces another wave, why would citizens believe the government will do better next time? Why wouldn’t they expect a repetitive cycle of lockdowns and outbreaks?

Lockdowns can be justified, but only for a few weeks to control a new wave, assuming there’s a solid plan to transition to dancing. The quicker the decline, the shorter and less dangerous the lockdown, allowing life to return to normal. The WHO recommends this approach. Otherwise, lockdowns should be avoided.

Fortunately, we’ve learned enough to recognize which social gatherings are safe and which are not.

For example, shopping with masks, social distancing, and hygiene appears largely safe, suggesting stores shouldn’t close. Research shows that most infections stem from a small percentage of events, indicating that targeting large gatherings can significantly reduce outbreaks.

So what should countries do?

• Prohibit gatherings exceeding a certain number, allowing larger crowds as cases decrease.
• Focus on high-risk locations, such as prisons, nursing homes, and food processing plants, and enforce stricter measures to prevent outbreaks.
• Close bars, clubs, and restaurants during high community transmission and avoid shutting down schools whenever possible.

The economy thrives on social interaction. When people can’t meet, consumption drops, harming the economy. Therefore, limiting social gatherings is the most costly defense and should be minimized unless other defenses are robust.

3. Counterinfection: Reduce Contagiousness During Interactions

The next layer of defense involves reducing the risk of transmission when people do meet.

While there is no term for "reducing contagiousness," I’ll use "counterinfection." Just as contraception prevents conception, counterinfection aims to decrease the risk of infection during social interactions.

The virus spreads under specific conditions: when many people gather indoors for extended periods while talking, singing, or even breathing. The Japanese refer to this as the 3 C’s: closed spaces, crowded places, and close-contact settings. My version is:

Avoid crowded, confined, and noisy interactions.

To effectively lower contagiousness, we must understand how the virus behaves and break down its transmission process.

Typically, an infected person coughs, talks, or breathes, releasing particles that linger in the air, potentially infecting others. When air circulation is poor, the virus can survive in the air until someone inhales those particles.

To curb the virus:

1. Avoid speaking near individuals from other social bubbles. Definitely refrain from singing or shouting.
2. Minimize the time spent with people from different bubbles.
3. Prevent the virus from escaping through the mouth and nose.
4. If it does escape, ensure proper air circulation to prevent particles from reaching others.
5. Create an environment hostile to the virus, enabling it to die quickly even in the air.
6. Ensure it does not reach another person's mouth, nose, or eyes.

The first point can be achieved by avoiding conversation or yelling in crowded settings. Some may mock Japan’s ban on shouting at amusement parks, but the country benefits from such measures.

The second point focuses on reducing interaction duration. If a meeting can last 10 minutes instead of an hour, make it shorter. Brief interactions are generally safe, while prolonged gatherings with many people should be avoided.

The third point involves wearing masks. Everyone should wear them in public, especially indoors.

The fourth point emphasizes the importance of outdoor gatherings, as the virus spreads very minimally in such environments.

Most outdoor activities should be allowed, except for large crowds at concerts or sporting events. Businesses should be encouraged to hold activities outdoors, and schools should aim for outdoor classes.

If outdoor activities aren’t feasible and must occur indoors, ventilation is crucial. Opening windows and using fans to circulate air is an inexpensive yet effective measure. A good ventilation system can significantly improve safety.

The fifth point highlights that the virus struggles to spread in optimal temperature and humidity conditions. High temperatures are beneficial for virus survival, with ideal conditions being around 25 to 30 degrees Celsius (approximately 75 to 85 degrees Fahrenheit) and humidity levels between 50% and 65%.

The virus seems to have evolved to thrive in cold and humid environments, similar to a bat cave. Additionally, our noses filter out the virus more effectively under higher humidity and temperature. Thus, if an indoor gathering is necessary, ensuring good ventilation and maintaining higher temperatures and humidity is advisable.

Lastly, instances of infection through contact with surfaces (known as fomites) are exceedingly rare. It remains essential to continue practicing hand hygiene.

The sixth and final step involves mask-wearing for protection. Most people understand the risks of inhaling the virus through their nose and mouth, but many forget that it can also enter through the eyes.

Wearing glasses or goggles could be beneficial. In a Chinese city where 32% of the population wears glasses, only 6% of COVID-19 patients did. Reports indicate that infections occurred among doctors without eye protection. The eyes have receptors for the coronavirus, and ocular symptoms are common in infected patients. This evidence suggests that eye protection could reduce the risk of transmission. For those who can afford it, this measure can be helpful.

While avoiding social interactions with different bubbles is costly yet relatively easy, reducing contagiousness is the opposite: inexpensive but challenging. Governments should prioritize effective implementation of this strategy.

4. Test — Trace — Isolate: Identify and Neutralize Infections

We’ve discussed preventing infections from entering a community, avoiding gatherings when they do, and reducing contagiousness during interactions. The final level of defense involves identifying and neutralizing infections as they occur.

This is accomplished through testing, contact tracing, isolation, and quarantines (collectively known as TTI: “test — trace — isolate”).

What should be a straightforward process has been poorly executed by many Western governments, with journalists failing to hold politicians accountable.

There’s a strong emphasis on testing, which is vital and necessary. The positivity rate (the percentage of positive tests) should be below 3 to 5%, and results should be rapid, ideally within 24 hours.

However, testing alone is insufficient. It identifies the infected individuals, but their contacts must also be quarantined, and compliance with isolation and quarantine measures must be ensured.

Regrettably, many governments have not hired enough contact tracers. A good rule of thumb is to have two to five times the number of contact tracers as there are daily cases. For example, a country with 5,000 daily cases should have between 10,000 and 25,000 contact tracers.

While this number is significant, the focus should be on their effectiveness. Governments should track what percentage of contacts of infected individuals end up in quarantine, aiming for at least 60%, ideally over 80%.

Contact tracers often follow the 90–90–90–90 rule: reach 90% of infected individuals, gather 90% of their contacts, reach 90% of those contacts, and quarantine 90% of them, all within two days or less, otherwise the virus has too much time to spread.

Unfortunately, in some areas, contact tracers struggle to achieve this for two reasons. First, people often block them, which should be penalized. It currently isn’t. Second, those who must quarantine suffer without compensation. Countries that have succeeded offer hotels, food, money, and frequent check-ins.

Fortunately, not every contact needs tracing. Japan has had success through a tactic called “cluster busting.” Most people don’t infect many others, so the focus should be on clusters. When a case is identified, determine where the infection occurred and pursue everyone from that location. If it wasn’t part of a cluster, move on.

This approach may be more difficult without contact tracing applications, which have proven to be ineffective in many cases but could assist in cluster management.

The challenge with contact tracing apps is that most people won’t download them unless required. Approximately 80% of the population would need to use such an app to gain control, but few countries have achieved even 40% adoption (e.g., Iceland at 40%, Canada at 15%, Singapore at 25%, Germany at 22%, and France at just 2.7%).

However, the crucial point is that you don’t need 80% usage across an entire country; you need 80% penetration within specific communities, such as those at risk of becoming clusters.

If entry to gyms, workplaces, bars, or family gatherings required scanning a QR code, compliance would likely be high. By scanning a code, an app can register who was present and when. If this requirement were mandatory for events, tracking would be simplified, allowing for swift identification of anyone who may have been exposed if an infection occurs. It is baffling why Western countries haven’t implemented such a system for social events.

Yet, this isn’t the most significant failure of Western governments. The greatest issue lies in the lack of support and enforcement of isolation and quarantine measures.

Testing and contact tracing provide the intelligence necessary for identifying who needs to be isolated or quarantined. Without action, intelligence is worthless.

Countries like Taiwan, Vietnam, and South Korea monitor devices or phones to ensure compliance with home isolation, imposing hefty fines and even prison sentences for violations. They utilize hotels and government facilities for isolation, providing financial support, food, and medication to those in quarantine. Western democracies have deemed these measures too challenging to enforce.

What happens next? In Norway, two-thirds of those required to quarantine have broken the rules. In the U.S., only one state (Hawaii) has managed to enforce quarantine compliance effectively.

Without enforcement or support, there’s no isolation or quarantine. Imagine the absurdity of lockdowns in countries that lack a robust TTI program. It’s like saying, “It’s too difficult to isolate a few individuals, so we’ll isolate everyone.”

Countries like Spain and France have had no qualms about enforcing lockdowns with significant fines. Yet we rarely hear about fines for isolation or quarantine violations because they simply don’t exist.

It’s time for governments to start enforcing these measures. This could be as simple as requiring individuals to send a selfie from home within ten minutes of a random prompt or sending police for random checks. Alternatively, they could simply replicate successful strategies from other nations. Additionally, they should provide food, financial assistance, and medication to those in quarantine to ensure compliance. For those infected who cannot isolate at home, hotels should be provided at no cost. Governments can secure these rooms at favorable rates, especially given the current low occupancy rates.

All of this is fundamental to the TTI strategy. However, in recent months, a new tool has emerged that could change the game: early detection.

Many countries have struggled with testing and contact tracing, the intelligence aspect. What if there were inexpensive methods to identify most potential infections quickly?

One option is wastewater analysis, which can effectively identify the virus in sewage systems and trace it back to the source. Some universities have successfully implemented this approach. It’s cost-effective and can indicate days in advance if a new infection or cluster is on the horizon.

Another method involves trained dogs, which can achieve accuracy rates of 100% in just ten seconds. This allows for much faster and cheaper screening of larger populations.

Finally, there are rapid tests: inexpensive tests that can quickly determine contagiousness and can be produced in large quantities.

Slovakia has recognized how transformative this can be, testing its entire population. With these tools, tens of millions can be tested daily, making the intelligence component of TTI extremely efficient, with minimal reliance on contact tracing. Yet, many governments remain unaware of this opportunity.

If everyone could move freely but had to undergo rapid testing and scan a QR code before entering a community, we could swiftly identify all infected individuals and isolate them while allowing others to resume their activities.

This approach could serve as a highly effective fourth layer of defense.

# The Swiss Cheese Strategy

These four layers are crucial for stopping the virus's spread: Fences, Bubbles, Counterinfection, and Test-Trace-Isolate.

None is perfect, and each has holes that might let infections slip through. However, together they create a nearly impenetrable defense. You can visualize this as layers of Swiss cheese.

An infection might breach one or even two layers. But with multiple defenses, the chances of it passing through undetected become minimal.

For example, imagine a country with a fence that stops 80% of infections, no social bubbles, a counterinfection strategy that eliminates 95%, and a TTI approach that neutralizes 50%. Combined, these layers capture 99.5% of cases. If the transmission rate (R) is 3, it would drop to 0.015! Each infected individual would infect only 0.015 others, effectively eliminating the outbreak within weeks.

Each of these four main layers comprises smaller, critical components: their effects are multiplicative. Each additional measure reduces infections further. The stronger they are, the more effective they become.

Once you establish these layers of defense, you can tailor them to suit your community, choosing those that are most effective and least costly.

Global Cheese Strategies

The strategy of each nation can be summarized by a combination of these defensive layers.

For instance, China implemented all layers from the outset. They closed borders, mandated lockdowns, enforced mask-wearing, and maintained a TTI program that included electronic monitoring of citizens, alongside mandatory isolation and quarantine. Unsurprisingly, they succeeded.

South Korea and Taiwan didn’t require such extensive measures. They focused on strong border controls, very localized and short-term lockdowns for social bubbles, masks for counterinfection, and world-class TTI programs. In other words, they relied heavily on layers 1 and 4, with minimal need for layer 3, the most costly.

New Zealand and Australia leaned heavily on layers 1 and 2. As sparsely populated islands, they could effectively prevent most infections from entering through their fences while managing local outbreaks with lockdowns. Even Victoria, Australia, utilized both a fence and lockdown to control the virus, reducing reliance on layers 3 and 4.

These countries have achieved near-zero prevalence, making it much easier to control the virus while reopening. Should outbreaks occur, they can be identified and neutralized quickly. Life is nearly back to normal in Taiwan, South Korea, New Zealand, and Australia. Attempting the same with a persistently low case count is much more challenging.

It’s certainly achievable, though. Japan has fluctuated between 0 and 10 active cases per 100,000 residents for months. How did they manage this? They excel in layer 1 with aggressive fencing, layer 3 with widespread mask usage and adherence to the 3 C’s, and layer 4 with their cluster-busting approach. It’s feasible.

The layer to avoid is the most expensive: layer 2, social distancing. It’s an expensive, ineffective measure.

The economy thrives on social interactions. When these interactions are halted, the economy suffers. The more communities develop layers 1, 3, and 4, the less they will need to rely on the costly layer 2.

Regrettably, Western nations have not learned to effectively utilize these less expensive layers, leading them to revert to the familiar, costly layer 2. They continue to damage their economies instead of learning to dance with the other layers.

# What Can You and Your Country Do?

Fractals: Your Community Can Take Action

Thus far, I’ve discussed countries because they typically have the authority to implement these four levels. However, they are not the only ones who can act. You can too.

You can apply this philosophy to any community: regions, cities, university campuses, nursing homes, meatpacking plants, prisons, businesses, homes, etc.

For instance, consider university campuses. What would layer 1, the fence, look like? They could test all students upon arrival and again four days later, keeping them isolated in their rooms during that time, providing daily meals and entertainment. Students would not be allowed to leave campus. If they do, they must quarantine again. Workers and visitors should be tested daily upon entry and prohibited from staying overnight.

For layer 2, social bubbles, they could reduce class sizes and form "bubbles" of students who socialize only with each other. Parties should be banned.

For layer 3, counterinfection, the school should provide high-quality masks and make their use mandatory. Classes that can be held outdoors should be prioritized, while indoor classes require open windows and appropriate ventilation. If temperature conditions are not ideal, schools should enhance ventilation and maintain warm, humid classrooms.

For layer 4, test-trace-isolate, the more rapid tests conducted daily, the better. Schools should purchase and distribute rapid tests for daily use. Otherwise, they should utilize wastewater analysis.

Students and staff must have access to contact tracing apps. All gatherings should require scanning a QR code created for that specific event. A positive test result should trigger immediate isolation, monitored through the app. Violations of isolation must be strictly addressed. All contacts of an infected individual should be promptly notified using the QR code, with self-quarantine measures enforced.

Applying this mindset is especially critical for communities and events prone to super-spreader events. If prisons, nursing homes, food processing plants, schools, universities, offices, and large private gatherings adopt these guidelines, they could halt the virus in their communities.

This, in turn, would help control it more broadly, as most cases stem from such super-spreader events.

There’s no need to wait for the government to do everything. We can all play our part.

Now that we know how to dance, the question becomes: do countries have the will to do so?

# Dancing Nations

If they do, the path forward is clear: in the face of uncontrolled outbreaks, implement lockdowns (layer 2) while swiftly enhancing other layers:

Layer 1: Fences - Announce a fence that includes testing upon entry and shortly thereafter, with a quarantine period in between.

Layer 2: Social Bubbles - Mandate a maximum gathering size (for example, 30 people, as seen in Sweden). Adjust according to local prevalence.

Layer 3: Counterinfection - Require masks when near others or in shared indoor spaces. Masks are not necessary outdoors if only family is nearby. - Strongly recommend eye protection indoors. - Allow most gatherings to exceed a certain number of people if they are outdoors with adequate spacing. - Require enhanced ventilation for indoor gatherings, with HEPA filters, higher temperatures, and the right humidity levels.

Layer 4: Test — Trace — Isolate - Conduct enough tests to maintain a positivity rate below 3 to 5% for PCR testing. - Announce an early detection strategy. - Employ approximately two contact tracers per daily case. - Require transparency in contact tracing effectiveness: what percentage of contacts of infected individuals are quarantined within two days? - Allocate resources to support individuals during isolation and quarantine with money, food, water, medications, and entertainment. - Make isolation and quarantine mandatory, monitored, and enforced. - Impose significant fines for violations of isolation and quarantine rules, and communicate those fines clearly.

This approach should be effective for most countries. But what if countries resist dancing? Or if they can’t? Argentina, for instance, has been in lockdown for seven months and still hasn’t controlled the virus. Others, like the U.S., have never truly made the effort. What alternatives do they have?

Should they attempt to mitigate the outbreak without completely suppressing the virus? Or simply allow the virus to run its course? And what about deaths? Chronic conditions? Treatments? Vaccines? How long will each of these take? How do they influence the strategies of different countries?

If you want to know the answers to these questions, subscribe for the next publication and let me know.

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Thanks to Yaneer Bar-Yam, Mick Costigan, Torsten Cordes, Carl Juneau, Barthold Albrecht, Mike Metzel, and Christina Mueller for your assistance while I wrote this article.