JONATHAN M. METSCH, Dr.P.H. – Tracking Emerging Public Health Challenges – July 19, 2026 – COVID
“Looking across the COVID-19 experience and the preparedness work now underway, 7 lessons stand out as most consequential for what comes next:”
Equity must be built in from the start. Inequitable access to vaccines, diagnostics, personal protective equipment, oxygen and therapeutics prolonged the pandemic and cost lives. Equity is not charity—it is a core requirement for health security. Preparedness must include equitable pathways across research, manufacturing, allocation, and delivery from the outset that reach those at highest risk.
Strong health systems are the foundation of resilience. Countries with strong community-based systems, robust primary care, public health networks and empowered health, and care workers were more resilient. Preparedness starts in everyday investments in workforce, surveillance, laboratories, and trusted services—long before an outbreak.
Speed, transparency, and trust save lives. Time lost is lives lost. Early detection, timely information-sharing, and clear, consistent risk communication are lifesaving. Systems should reward transparency, not penalize it. Misinformation must be addressed with the same urgency as the pathogen itself, because trust is just as vital as any medical countermeasure.
We must break the cycle of panic and neglect. In every crisis there is a rush to act—and then a rush to forget. Preparedness cannot survive on emergency attention alone. It must be embedded in long-term planning, budgets, and routine public health work, with regular exercises and accountability.
Effective governance accelerates action. When roles are unclear and coordination fragmented, response slows. Stronger global governance—anchored in the WHO International Health Regulations (IHR) and reinforced through the WHO pandemic agreement creates clarity and accountability; conditions for faster, collective action [5, 6].
Preparedness and prevention must embrace One Health. Threats with epidemic and pandemic potential emerge at the intersection of human, animal, and environmental health. Coordinated action across human health, animal health, agriculture, environment, wildlife and climate sectors, before outbreaks begin, is the only way to reduce spillover risk and amplification at its source.” (1)
In February 2020, the largest COVID-19 outbreak outside of China’s borders wasn’t in a neighbouring country or a crowded urban centre.
It was on a cruise ship: the Diamond Princess.
The ship’s passengers had been enjoying a luxury vacation on this immaculate, floating mini-city — at first, blissfully unaware of the invisible threat, then abruptly locked in their cabins for quarantine. As The Covid Cruise, a documentary from The Nature of Things shows, it quickly became a nightmare for some of the 3,700 passengers and crew onboard.
“The Diamond Princess was different than other outbreaks because we were playing catch up,” says Dr. Michael Callahan in the film. “The disease was clearly rolling ahead of us and there was a huge percentage of patients that were infected that had [yet] to become symptomatic.”
The Diamond Princess found itself in the unfortunate circumstance of providing a critical case study of the novel virus — in fact, the ship’s outbreak was examined by epidemiologists around the world.
The Covid Cruise interviews experts, journalists, passengers and crew members about the deadly, unprecedented pandemic aboard the ship. Here’s what was learned.
‘Cruise ships are perfect environments’ for disease spread
Thousands of people in close quarters is an ideal environment for potential infection spread.
“The cruise ships provided the natural experiment where we got to see how the virus would propagate very quickly,” says Callahan, an expert from the Division of Infectious Diseases at Massachusetts General Hospital and Harvard Medical School.
“Any droplet that’s expelled by somebody talking or coughing can be suspended in the air and someone who’s vulnerable, oftentimes elderly, might walk into that droplet cloud within five to 10 minutes and become infected.”
Passengers describe the mood on the ship when the Captain came over the intercom during one of the final celebratory meals to announce a passenger had tested positive for Covid-19. For many, the partying continued.
According to an industry association, cruise ship passengers have a median age of 60 to 69 years old, and another 14 per cent of passengers are over 70 — a demographic that can be more vulnerable to COVID-19. And air quality aboard a ship, Callahan says, is particularly hospitable for a virus to spread.
“Cruise ships are perfect environments to protect fragile viruses from the natural forces that destroy them, such as ultraviolet light, sunshine,” he says. “The air quality is perfect for coronaviruses in particular — they like it dry and they like it air conditioned (…) So those staterooms on the cruise ships are ideal environments to keep those viruses alive for potentially a couple days, whereas in an outside environment, they might not last tens of minutes.”
Crew quarantine is crucial
Government officials, crew — nobody was prepared
Kentaro Iwata, professor of infectious disease at Kobe University, says “zoning” would have been a critical measure against a virus outbreak: confirmed cases should stay in a red zone, and healthy passengers in a green zone. There should be no cross-contamination between the two, and personal protective equipment (PPE) is mandatory in a red zone.
But when Iwata boarded the Diamond Princess, he saw government officials touring around the ship without PPE.
“A lot of bureaucrats, they were just going back and forth,” he says, “back and forth between the green zone and red zone, without having appropriate protections. This is an unthinkable thing for the infection prevention specialists.”
Most of the [crises] that we’ve been taught to deal with is a ship sinking, pirates are coming on and off, so all those sorts of stuff,” she says. “But a virus, that was something that we never heard of, so we didn’t know what to do.” (2)
“One finding stood out: Many nonprofits that mobilized to help Ukrainian refugees weren’t starting from scratch. Instead, they were able to rely on existing partnerships, volunteer networks and systems they had developed during the COVID-19 pandemic. The experience they gained during one crisis helped those organizations respond more quickly to the next.
We also found that nonprofits were central to delivering assistance but were rarely included in decisions about how that assistance was organized. They housed refugees, coordinated volunteers, distributed supplies and helped families connect with housing, schools, healthcare and government services. Although the central government depended on nonprofits throughout the crisis, many nonprofit leaders had little say in planning and coordinating these efforts at a national level.
In our study, which we published in Nonprofit Policy Forum, an academic journal, in June 2026, we found that the nonprofits working most closely with refugees had unique, firsthand knowledge of changing needs. Yet that experience was not always incorporated into government planning and decision-making.” (3)
“The UK’s pandemic preparedness is now undergoing reform. In March 2026, the government introduced a new pandemic preparedness strategy. This outlines measures being taken to improve health protection, surveillance, testing, vaccines and treatments.
The first priority should be understanding where critical products come from and where supply chains are most vulnerable.
Hospitals and government agencies should map essential medicines, PPE and medical equipment from manufacturing through delivery. This will identify products that depend on one supplier, one country or a small number of factories. Such intelligence would allow measures to be taken to build stockpiles safely and responsibly.
Different disruption scenarios should then be tested. This would allow decision-makers to determine which scarce or difficult-to-replace products require larger emergency reserves—and which products can be sourced locally or delivered quickly when needed.
Speed and price should not be the only metrics for procurement decisions. Product quality, supplier reliability, manufacturing location, delivery times and environmental impact are also essential. Practicing value-based procurement, which aims to trade with suppliers based not solely on cost but also on their ability to perform well, will help address this.
Supplier diversification is essential as well. The UK should avoid depending too heavily on one company, country or manufacturing region for supplies.
A stronger system would combine trusted international suppliers with local production, nearshoring and pre-agreed emergency partnerships. Diversification of supply should help reduce shared points of failure.
Clear accountability is equally important. A named organization or senior leader should be responsible for monitoring critical PPE supplies, responding to warning signals and ensuring recommendations from inquiries and emergency exercises are implemented.
When responsibility is spread across too many organizations, preparedness can become everybody’s concern—with limited visibility and accountability. Appointing a named specialist to oversee a specific unit or task force can raise awareness of the importance of critical supplies and help address this issue.
This may also help reduce interdepartmental conflict within the government so that progress can be made.” (4)
1.Preparing for the Next Pandemic: Learning From COVID-19 to Build What Comes Next, by Maria Van Kerkhove, https://academic.oup.com/ofid/article/13/7/ofag348/8728458
2.What we learned about COVID-19 from the Diamond Princess, by Nina Dragicevic, https://www.cbc.ca/documentaries/the-nature-of-things/what-we-learned-about-covid-19-from-the-diamond-princess-1.5814190
3.Czech nonprofits applied lessons learned during the COVID‑19 pandemic to the Ukrainian refugee crisis – but had little say in key decisions, by Tara Kolar Bryan, https://theconversation.com/czech-nonprofits-applied-lessons-learned-during-the-covid-19-pandemic-to-the-ukrainian-refugee-crisis-but-had-little-say-in-key-decisions-285905
4.COVID PPE failures left health care workers and patients at risk: What lessons the government needs to learn, by Emilia Vann Yaroson, Liz Breen, https://medicalxpress.com/news/2026-07-covid-ppe-failures-left-health.html
curated by Jonathan M. Metsch, Dr.P.H.
Clinical Professor of Environmental Medicine, Icahn School of Medicine at Mount Sinai