War can be the cause of, and the perpetuation of, a public health emergency. The current Russian-Ukrainian conflict is no exception, and warrants a discussion of whether invading a country in the midst of a global pandemic constitutes an act of biological warfare. A look back in history can help us explore this question.
The First Act of Biological Warfare: The "Black Death"
In the year 1346, in the port city of Kaffa (now modern-day Theodosia) on the Crimean Peninsula of the Black Sea, the consequences of a different war were unfolding. In that time, Italian notary Gabriele de' Mussi wrote:
"One infected man could carry the poison to others and infect people and places with the disease by look alone. No one knew, or could discover, a means of defense...the scale of the mortality and the form which it took persuaded those who lived...that the last judgement had come."
We know now that de' Mussi was in fact describing the horrors of Yersinia pestis, in what came to be called bubonic plague or the Black Death.
The city of Kaffa came under attack by a Mongol army controlled by Kipchak khan Janibeg, a descendant of Genghis Khan. Janibeg laid siege to the city to remove Genoese forces from an important defensive position in order to alter the European sphere of trade influence. But the Mongols miscalculated the level of resistance and the war dragged on for years, until, as de' Mussi later wrote:
"...the whole army was affected by a disease which overran...and killed thousands every day...all medical advice and attention was useless."
Janibeg eventually called off the siege, but not before ordering that the bodies of soldiers felled by the plague be launched via catapult into the city in the hopes of decimating the population. This has been seen as the first intentional act of biological warfare in recorded history and contributed to the explosion of arguably the most devastating pandemic in world history. It has been postulated that Italians fleeing the carnage on ships brought the plague to their home ports (amongst other routes of transmission). Within a year, the plague had gained a firm grip on the European continent. Within 5 years it has been estimated that as much as 40% of the global population was killed, corresponding to 200 million people.
Flash Forward to Modern Day: The COVID-19 Pandemic
Though over 600 years have passed since that pandemic (to use the modern term), we find ourselves in the midst of a new war during a global pandemic in the same region where the Black Death exploded. As expected, the risk of greater spread of COVID-19 and threats to an already strained healthcare system are significant.
Though data is scant from Russia, according to the Russian Ministry of Defense as of December 2021, military vaccination against COVID-19 was broadcast as upwards of 95%, with 25% receiving boosters. Despite this, the Russian army is not invincible, especially in the face of Omicron, and cases have reportedly been spreading throughout units. Reports (though unconfirmed) have estimated the Russian military has been losing almost 300 troops daily to injury or death. With images of soldiers being left on the battlefield and military units refusing to fight and surrendering, one has to wonder whether COVID-19 is a factor.
Potentially infected Russian troops create a health hazard as they increasingly mix with the Ukrainian population, engaging in warfare in close quarters and being taken as prisoners by the Ukrainian army (or vice versa). The Ukrainian population has a low rate of people fully vaccinated against COVID-19 at only 35%, and just over 36% having received at least one dose. With such low vaccination rates, COVID-19 can continue to spread. Like many other countries, Ukraine had a significant surge in cases in November and February during the Omicron spike, but that doesn't negate another surge or the emergence of new variants. And while the Ukrainian military reportedly has a 99% vaccination rate, its ranks have increasingly been infused with civilians defending their homeland, many of whom are unvaccinated. The close contact they will have with Russian prisoners will almost certainly increase the likelihood of continued COVID-19 transmission. Additionally, having people cramped indoors in bomb shelters and subway stations without access to health services poses a serious risk. As the remaining Ukrainian population huddles together for safety and over 1.7 million and counting flee the country into neighboring European lands -- some of which, like Poland, have waived their standard coronavirus quarantine and testing requirements for refugees -- such actions may tragically create more opportunities for COVID-19 to spread, much like the Black Death.
Healthcare workers in Ukraine must not only contend with traditional battlefield casualties, but also the consequences of additional COVID-19 infections. This becomes exceptionally challenging given that the oxygen supply to Ukrainian hospitals is already at the point of exhaustion. Moreover, electrical shortages from the invasion pose immense risk to hospital systems and supplies including ventilators, dialysis machines, and lights. Other critical supplies are increasingly unavailable. Médecins Sans Frontières (Doctors Without Borders) suspended normal operations in the country the last week of February, and staffing shortages are already apparent. The world is receiving reports of hospitals and healthcare workers deliberately being targeted by the Russian military, using internationally banned weapons, such as cluster munitions. As of today, the WHO confirmed at least 14 attacks on Ukraine's healthcare facilities -- killing 9 people and injuring 16 -- and classified two more attacks as possible.
We posit that launching this invasion in the midst of the COVID-19 pandemic constitutes a form of a biological warfare, intentional or not. Biological warfare occurs when a state uses a disease-causing agent in waging war. While the 1972 Biological Weapons Convention specifically bans microbial or other biologic agents for use other than peaceful or protective purposes as well as the production of weapons or equipment designed to deliver these agents during conflict, the Soviet Union, parent of the current Russian government, has a long history of treaty noncompliance. While exacerbating the spread of COVID-19 may not have been Russia's primary goal when invading Ukraine, it is an obvious side effect that Russian leaders had to be aware of when they made the decision to invade. Accordingly, this may constitute biological warfare, especially when hospitals and healthcare workers are indiscriminately targeted, violating international rules of war.
As the war grinds on, the world sits on a precipice. Up to now, impasse is leading to escalation. When war stops, the full impact on the health of the population will ultimately be revealed.
Gavin Harris, MD, is an assistant professor of infectious diseases and critical care at the Emory University School of Medicine in Atlanta. His clinical expertise and research interests include disaster preparedness and biosecurity, medical education and the care of critically ill patients, and scholarly work in military history and the history of medicine. Joel Zivot, MD, is an associate professor of anesthesiology/critical care at Emory University School of Medicine. His clinical expertise and research interests include care of critically ill patients in the OR and ICU, education, and scholarly work in bioethics, the anthropology of conflict resolution, law, policy, and a variety of topics related to anesthesiology/critical care monitoring and practice.