I see two stealthy viruses as the most plausible triggers for the next major health crisis, both already circulating quietly in humans and animals. Drawing on recent warnings from Jan and other infectious disease experts, I focus on Influenza A and mpox, which combine global reach with worrying evolutionary room to maneuver.
Influenza A
Influenza A is, in my view, the archetypal stealth threat, because it is already everywhere yet still “on the cusp of a pandemic,” as Jan and colleagues have stressed in detailed reviews of seasonal and avian. The virus infects a wide range of animals, including birds and pigs, which creates constant opportunities for genetic reassortment and the emergence of novel subtypes. Scientists tracking more than 30 high‑risk pathogens now routinely place influenza A near the top of lists of viruses that could ignite the next pandemic, alongside dengue virus and monkeypox virus, because of its proven ability to jump species and spread efficiently between people.
Recent assessments of “pandemic potential” viruses have highlighted avian influenza A as a particular concern, with some strains linked to severe respiratory disease and even brain swelling that evokes Victorian‑era killers in its lethality profile, according to analyses of emerging flu complications. I read these findings alongside broader scientific warnings that influenza A is one of the pathogens most likely to spark a global emergency, as outlined in expert mapping of future pandemic drivers. For health systems and policymakers, the implication is clear: surveillance in birds and pigs, rapid vaccine updating, and stockpiled antivirals are not optional extras but core defenses against a virus that is already testing the edges of our preparedness.
Mpox (monkeypox virus)
Mpox, caused by the monkeypox virus, has shifted from a rare zoonotic curiosity to a persistent global threat, and I see that trajectory as a warning sign. Jan and other experts now track mpox alongside influenza A as a virus with genuine pandemic potential, noting that Old viral foes are constantly evolving and exploiting new ecological niches, as summarized in recent overviews of emerging viral threats. The 2022 global outbreak demonstrated that mpox can sustain transmission through close contact, often via sex, far beyond its historical strongholds, and that existing public health systems were slow to recognize and contain the spread.
In detailed technical briefings, Jan has underlined that mpox is now worldwide and liable to affect travelers in the Americas, while also stressing that there are no widely available, highly effective treatments, a gap documented in analyses of current mpox control. I interpret this combination of global reach, human‑to‑human transmission, and limited therapeutics as a classic recipe for a stealth crisis. For governments, sexual health services, and vaccine developers, the stakes are high: without sustained investment in targeted vaccination, diagnostics, and community‑led outreach, mpox could entrench itself as a chronic, globally distributed infection that periodically flares into emergencies, stretching already fragile health systems to the breaking point.
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