Refugees from Ukraine arrive in Medyka, Poland after crossing the border from Shehyni, Ukraine on Feb. 25, 2022.
Michael Kappeler—picture-allianc/AP
March 2, 2022 4:11 PM EST

Ukraine was struggling to control the COVID-19 pandemic even before Russian troops advanced on the country. It was slower to launch its COVID-19 vaccination campaigns than other European countries, and while the government encouraged citizens to get immunized, most people struggled to find a way to get the shot, didn’t feel the need to get vaccinated, or didn’t trust the safety and efficacy of the vaccine.

Just before the invasion on Feb. 24, only 35% of the Ukrainian population had been vaccinated. That puts it in line with most of its neighboring countries, although some, including Poland and Hungary, have achieved higher vaccination coverage. While different health systems and varying attitudes about vaccination in those countries are contributing to those contrasting rates, Ukraine’s relatively low vaccination rate could have implications for how large additional surges of cases, both in the country and in the region become as a result of the war. Like many other countries, Ukraine experienced a surge in cases due to the Omicron variant in November and another peak in the first week of February—most likely due to its low level of vaccination. By the middle of February, 60% of COVID-19 tests conducted in the country were positive.

Such low vaccine coverage isn’t enough to control a highly transmissible virus like SARS-CoV-2, say public health experts. Add in a war—with the political and social upheaval it causes—and not only are spikes in infections inevitable, but there is also the potential for new variants to emerge, which puts the whole world at risk.

Vaccination and mitigation measures such as mask-wearing, social distancing, and basic hygiene are critical for curbing spread of SARS-CoV-2, but are impossible to maintain when a country is under siege. The humanitarian group Doctors Without Borders has been distributing trauma kits and training health care providers in Mariupol, Ukraine—a target of the Russian attack—as well as providing shelter and basic health needs for those crossing the border into other countries like Poland. But it’s not enough.

“War is an infectious disease’s best friend,” says Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “It challenges every public health program you can possibly have. It limits the medical care available for those who might be seriously ill, and often fosters transmission when so many people are crowded into bomb shelter locations and on trains. This is going to be the perfect storm of one serious challenge after another.”

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A decade and a half ago, World Health Organization researchers found that 65% of major infectious disease outbreaks occurring in the 1990s were among refugee populations or in conflict zones. Les Roberts, professor emeritus of Columbia University’s Mailman School of Public Health who has spent time in war zones addressing outbreaks, notes that these populations are especially vulnerable to viral diseases like COVID-19. “It turns out when you are under stress, your immune system does not work as well. You are not eating as well, and you cannot fight disease as well,” he says. “And in times of conflict, you move around a lot, and end up in bomb shelters or basements or on trucks that are way more crowded than normal and have bad air circulation. I don’t think people fully understand how war is like the breeding ground of disease.”

More than 670,000 people have left Ukraine since the war began, and this increased travel will almost certainly lead to a spike in cases in the country and those bordering it—like Poland, Hungary, Slovakia, Romania, and Moldova—while straining their health care systems. Health experts are particularly concerned about the situation in Poland, where almost half of the Ukrainians have fled, according to the U.N. High Commissioner for Refugees. “SARS-CoV-2 spreads like lightning right now,” says Jeffrey Shaman, professor of epidemiology at Columbia University Mailman School of Public Health. “For places like Poland and places in western Ukraine where people are fleeing, there is enormous opportunity for this virus to do damage that it wouldn’t have had the opportunity to do otherwise.” Prior to the influx, nearly 60% of Poland’s population was vaccinated, which will help protect it against a surge, but new infections will likely spike there as well, increasing demand for health care services.

“We have warned for years about the potential convergence of conflict and epidemiology—bad things happen when those things converge,” says Dr. Eric Toner, senior scholar at the Johns Hopkins Center for Health Security. “Certainly, in the dire circumstances in which the population is right now, mask-wearing, distancing, and quarantine are not going to be possible. As people flee the affected parts of the country, crowding on buses, trains, and cars and ending up in hotels or living with relatives or in refugee settlements—those are not conditions for good control of a transmissible disease like COVID-19.”

Hospitals will likely be hit hardest by the influx of refugees during the pandemic, say public health experts. War-related injuries will take precedence over COVID-19 care, which will only make it easier for the virus to spread. That disruption will in turn lead to more health care workers who will get infected, and won’t be able to perform their duties.

“There will be runs on hospitals and facilities and resources because of injuries associated with the conflict,” says Shaman. “In the longer term, I imagine it will result in deterioration of the ability to deliver health care at the level that people in the Ukraine are used to having.” And if surges occur in neighboring countries as well, that puts additional pressure on health care services in the entire region. “The world community would be advised to provide supplies and facilities to buffer the displaced Ukrainians and Polish populations from those consequences.”

Shaman and other public health experts are also concerned about longer term effects of the conflict on COVID-19 control. Studies consistently show that vaccine-based immunity starts to wane after about five to six months. Booster shots are essential to maintaining protection against disease so severe that it requires hospital care; if the conflict in Ukraine continues, that would mean even vaccinated citizens will not be able to get boosted as trauma care and war-related injuries will take priority over vaccination efforts.

Read More: Europe’s Illusion of Peace Has Been Irrevocably Shattered

The situation exposes the weaknesses in the global biodefense network against threats like highly infectious coronaviruses. Even without a military conflict, stark inequities in health resources have led to profound differences in countries’ ability to control COVID-19; developed nations have been able to purchase and distribute vaccines, while poorer countries, mostly in Africa and parts of Asia, still struggle to contain the virus since they lack access to the shots. When a conflict like that occurring in Ukraine right now hits during a pandemic, the lack of global coordination of public health resources becomes more tragically obvious. “I can’t begin to tell you where the solution is,” says Shaman. “The World Health Organization doesn’t have the authority or the resources in terms of money to deal with this. This is a very large issue that involves development, nation sovereignty, and the ability of nation states to get along and support one another in a trusting way rather than in ways that we’ve seen the world devolve into over the last 20 years.”

What’s truly needed is a global coordinating body for public health, Toner says, which isn’t likely, given challenges posed by issues of national sovereignty. But the principles behind global coordination might still be implemented in more limited ways.

The global vaccination distribution program COVAX, through which developed nations purchase vaccines in order to drive prices down for developing countries, represented such an effort, but is falling short of meeting its promise. It failed to deliver the 2 billion doses it had guaranteed by the end of 2021, and the group estimates that it will take until well into 2023 to provide enough vaccines to immunize the world. “After the pandemic is over, I think we need to take a real look into COVAX and why it didn’t work as well as we had hoped, and what we could have done to make it better,” says Toner.

Some public health experts have proposed alternatives, like supporting vaccine makers to set up manufacturing facilities in countries that have historically struggled to get the latest vaccines, as well as encouraging more shared intellectual property to enable poorer countries to access the technology they need to produce shots on their own.

Roberts points out that there are also ways to control and reduce the likelihood of viral spread as Ukrainians gather in shelters and flee to other countries. Vaccinating and boosting people who enter these communal settings—especially those who are particularly vulnerable, such as the elderly or people with underlying health conditions—is an important start.

However, that’s still mostly out of reach. The World Health Organization doesn’t have enough resources to quickly direct vaccine supplies and personnel to crisis zones such as Ukraine, and lacks political authority to address questions of national sovereignty. Organizations such as Doctors Without Borders and other humanitarian groups also play critical roles, but are equally restricted to more localized aid efforts. “If we continue to be reactive in crisis after crisis, then we will not get at the systemic, underlying issues that need to be solved,” says Shaman.

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