Governments around the world are desperate for coronavirus vaccines, with many battling publicly for limited doses and accusing others of hoarding. Yet amid this rush, some countries are not only refusing potential doses produced by rivals but officially banning them.

Ukraine recently banned Russian vaccines, despite new peer-reviewed data that suggests a high efficiency for Moscow’s leading candidate, Sputnik V. The Iranian government, on the other hand, has banned all U.S.- and British-made vaccines and approved Sputnik V.

In Taiwan, where officials have spoken out since last year against vaccines made in China, authorities recently reiterated that imports of these vaccines are banned and warned that Taiwanese civilians living in China could face quarantine when they return home.

It is an inversion of the logic of vaccine nationalism, which has led powerful nations to scoop up as many doses as they can in hopes of emerging from the pandemic. More than 80 million vaccine doses have been given out in more than 50 countries, with some speeding well ahead.

But Ukraine, Iran and Taiwan have not formally begun their vaccination programs. And while Taiwan has been widely praised for its successful handling of the pandemic, Ukraine and Iran have struggled, resulting in considerable death tolls.

To experts, it’s an alarming, although not necessarily surprising, trend.

“It’s a combination of political considerations, whether they even have the option [of acquiring the vaccine], as well as the concerns about effectiveness and safety of the vaccines,” said Yanzhong Huang, a senior fellow at the Council on Foreign Relations.

Pavlo Kovtoniuk, Ukraine’s deputy minister of health from 2016 to 2019, said Kyiv’s concern with Moscow-backed vaccines was not just political but a matter of national security.

“Over the last few decades, and especially during the previous seven years of undeclared war, Ukraine has well learned what hybrid warfare is,” Kovtoniuk said.

Ukraine

Despite growing political anger over a lack of vaccine in the country, Ukrainian lawmakers last week approved a bill that officially banned vaccines made in Russia.

With a population of more than 40 million, Ukraine is one of the largest European countries to not begin its formal vaccine rollout. President Volodymyr Zelensky is facing record-low approval ratings amid a pandemic that has infected 1.25 million and caused more than 23,000 deaths.

Part of the concern is about aspects of safety and efficiency: Phase 3 testing data for Sputnik V was released long after the vaccine was rolled out in Russia.

But while new data released Tuesday may ease scientific concerns, broader national tensions remain. Since 2014, Ukraine has had a tense relationship with Russia, which has backed separatist rebels in the country’s east and annexed the Crimean Peninsula.

The Russian government had already started administering Sputnik V in Crimea, which is viewed as part of Ukraine by most international powers. This week, Russian-backed separatist areas in eastern Ukraine also began using the vaccine.

“It’s reasonable to say — as the Russians are saying, loudly — that vaccine access should transcend geopolitics, and everybody should get high-quality vaccines from wherever they can,” said Judyth Twigg, a professor at Virginia Commonwealth University who tracks public health in Ukraine and Russia.

“But it’s also naive to ignore the geopolitical implications,” Twigg added.

While Ukraine is unlikely to reverse its decision on Russian-backed vaccines, at this stage it has few alternatives.

Through the global Covax program, Kyiv secured 8 million doses of the vaccine developed by U.S. pharmaceutical giant Pfizer and Germany’s BioNTech. The first round, due later this month, is expected to bring only 200,000 doses.

Ukraine also turned to Beijing to bolster its supplies, signing a deal for 1.8 million doses of China’s Sinovac vaccine in December.

Kovtoniuk said that if Ukraine cannot get more U.S. or European vaccines, it might turn to more Chinese producers. He said it was Russia, not Ukraine, that was politicizing vaccine supply. “It is a matter of politics and influence, first of all for Russia, not for Ukraine,” he said.

Iran

Iran has been hit badly by the coronavirus, reporting more than 1.42 million cases and almost 60,000 deaths. But in January, the country’s supreme leader announced that the country had banned the import of vaccines made in the United States or Britain.

Ayatollah Ali Khamenei made the announcement in a televised address Jan. 8, calling the vaccines “forbidden.” The supreme leader named the Pfizer-BioNTech vaccine as one of the products that would be banned, despite its approval by other nations and high reported efficacy.

“They are completely untrustworthy,” he said. “If they were able to create a vaccine … why do they want to give it to us? Why don’t they use it themselves?”

Iran approved Sputnik V in late January and was hoping to jointly manufacture some doses. State media has reported that the first doses of Sputnik V are expected to arrive this week. Iran is also expected to eventually receive 1 million vaccine doses from China.

Amir Afkhami, an expert on the country’s public health system at George Washington University, said that while Iran has been relatively successful in treating recent pandemics, the Iranian supreme leader has “a long history of conspiratorial constructs and mind-set around biomedical issues.”

Afkhami said there were some practical reasons that Iran might favor a Russian vaccine rather than a U.S.-backed vaccine — at an estimated $9.95 per dose, Sputnik V is probably one of the cheaper vaccines. However, he said that the justification was probably an attempt to “portray the regime as competent in view of the many missteps it’s had during the pandemic.”

Khamenei’s move to block some foreign vaccines came amid Iranian claims that U.S. financial sanctions were blocking access to Covax, which has bought doses of a number of U.S.- and British-backed vaccines.

The Iranian Medical Council, the country’s main physicians association, pushed back on the decision after Khamenei’s announcement. “All decisions should be based on science,” the group said in a public letter.

Taiwan

Taiwanese officials reiterated last month that vaccines made in China were banned from import, with the island’s Mainland Affairs Council telling Reuters that vaccination was a medical matter and that it “should not be used as political propaganda.”

The announcement came after reports that China, which claims sovereignty over self-governing Taiwan, was offering free domestically produced vaccine to the roughly 400,000 Taiwanese citizens who live in China.

Taiwan’s government has cast doubt on vaccines made by Chinese companies such as Sinopharm and Sinovac, publicizing rules that say anyone who receives the vaccines would be required to quarantine upon arrival in Taiwan.

Huang said there were genuine health concerns about Chinese-made vaccines. Like the developers of Sputnik V, Chinese developers had not released full Phase 3 data before making their vaccines available. Early data from some countries suggested they were notably less effective than some rivals.

“There are political concerns, but there are also big concerns about the safety and effectiveness of China-made vaccines,” Huang said.

Although vaccinations are not expected to begin until March, Taiwan has procured around 15 million doses for its population of 25 million. Ten million of the doses come directly from British-Swedish firm AstraZeneca and 5 million through the Covax program.

A representative of the Taipei Economic and Cultural Representative Office in the United States said that negotiations were ongoing for an additional 5 million doses.

However, Taiwan has a luxury that Ukraine and Iran do not have — a relatively contained outbreak. With only 912 confirmed cases, eight deaths and tightly controlled borders, the island has resumed relatively normal life, although mass gatherings remain discouraged.