CNN  — 

Global health officials have warned that there will be a rise of Covid-19 cases in Ukraine tied to Russia’s invasion, but doctors also worry about a surge in other infectious diseases: polio, cholera and measles.

Before the war, Ukraine had low vaccination rates against those diseases, Kate White, an emergency program manager for Doctors Without Borders, told CNN on Tuesday.

Now, doctors on the ground in Ukraine worry that a rise in these vaccine-preventable infectious diseases will be another consequence of Russia’s invasion – and that even more lives could be lost to the spread of disease.

“In terms of what we call vaccine-preventable diseases, the status in Ukraine was that the population was not vaccinated to the extent which you would get herd immunity like you would in many other European countries or in the US,” White said.

Not only have vaccinations been low, the administration of routine immunizations “is no longer functioning” because the nation’s health system has been “disrupted.”

“Then, on top of that, you have the overall public health situation – so many cities where lack of access to health care is compromised, some places where they no longer have the water supply that they used to, they don’t have electricity, there’s issues with sanitation – so all of these risk factors pile up on top of each other, which means that there is an increased risk,” White said, referring to diseases like cholera that usually spread in places with inadequate water treatment, poor sanitation and inadequate hygiene. Meanwhile, the risk of polio and measles rises as more people gather and flee the area while medical supplies dwindle.

Ukraine has seen outbreaks of these diseases before.

“There was a polio outbreak in Ukraine last year,” White said. “Ukraine was the last country within Europe to have a cholera outbreak in 2011, and that was in Mariupol.”

Today, the city of Mariupol remains a site of major Russian attacks and damage.

Conditions in Mariupol are “unbearable” and “just hell,” residents who fled the besieged city in southeastern Ukraine have told CNN, as drone footage and satellite photos have emerged showing utter devastation wrought by the Russian bombardment.

As many as 2,500 civilians have died in Mariupol, Ukrainian officials estimate. About 350,000 people are trapped in the city, with officials warning that those who remain are without electricity, water and heat.

‘We’re only at the start of the burden’

The growing concern around a surge of infectious diseases comes as a number of hospitals and health facilities in Ukraine are no longer functioning – or have been attacked or under siege.

On Tuesday, a Ukrainian official accused Russian troops of holding people captive at a Mariupol hospital. Pavlo Kyrylenko, the head of Donetsk regional administration, said doctors and patients were being held against their will in the Mariupol regional intensive care hospital, also referred to as Hospital No. 2.

In a statement posted on his official Telegram channel, Kyrylenko said that one of the hospital employees managed to pass on information about what was happening.

“It is impossible to get out of the hospital. They shoot hard, we sit in the basement. Cars have not been able to drive to the hospital for two days. High-rise buildings around us are burning. … The Russians have rushed 400 people from neighboring buildings to our hospital. We can’t leave,” Kyrylenko said, quoting the employee.

Kyrylenko said that the hospital was “practically destroyed” several days ago but that its staff and patients stayed in the basement, where the patients continued to be treated.

The World Health Organization, the United Nations Population Fund and UNICEF released a joint statement Sunday noting that since the start of the war in Ukraine, at least 31 attacks on health care have been recorded in its Surveillance System for Attacks on Health Care.

In 24 of those incidents, health care facilities were damaged or destroyed, and in five cases, ambulances were damaged or destroyed. In their statement, the groups called for “an immediate cessation of all attacks on health care” in Ukraine.

“These attacks have led to at least 12 deaths and 34 injuries, and affected access to and availability of essential health services,” the statement says. “WHO is verifying further reports, as attacks continue to be reported despite the calls for protection of health care.”

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There are more people needing care but with fewer hospitals available within the country, White said, adding that there are two “medical elements” taking priority.

For one, “there’s those cases that are related to trauma, whether that be conflict-related trauma or even things like road accidents,” White said. Then, “there are also a few other chronic diseases that are starting to hit more and more.”

People in Ukraine with certain chronic diseases have lost access to their medications due to the war, and their conditions – such as diabetes or hypertension – now could be uncontrolled and worsening. This could lead some of them to need hospital care, too.

Sadly, these public health consequences of war are not unique to Ukraine, White said.

“Unfortunately, I don’t think there is anything particularly unique, and that really actually breaks my heart that I’ve seen this too many times before,” White said. “We’re only at the start of the burden that the health system is going to face as this conflict continues.”

CNN’s Ivana Kottasová in Lviv and Marina Marukhnych in Odessa contributed to this report.