The world is on the precipice of a global vaccine war that could wreck the fight against COVID-19

• The EU may have fired the first shots in a global vaccine war.
• European threats to impose export controls on vaccine supplies could spread across the globe.
• A leading international trade group told Insider the EU had cast a "cloud of uncertainty" over the world.

The ugly row last week between the European Union and drugs giant AstraZeneca, which resulted in the EU threatening to blockade exports of European-produced vaccines, is an early sign of the sort of vaccine nationalism that could be about to spread right across the globe.

The EU has threatened to restrict the export of vaccines to third countries, including the UK, amid widespread disquiet about the slow roll-out of vaccines on the continent.

Brussels ultimately rowed back from the most controversial part of its plan, which would have seen a border imposed on the island of Ireland, following international outrage, not least from Ireland itself, a member of the EU.

However, industry leaders have serious concerns that the EU's actions will trigger other nations and trade blocs to follow through on similar plans and plunge the world into a series of damaging vaccine trade wars.

They fear that the EU's decisions have sent a dangerous signal to the world that "vaccine nationalism" is an acceptable tactic for dealing with the pandemic.

One senior international trade figure, who asked not to be named, told Insider this week that "the European Commission's move last week had opened a Pandora's box."

They added: "It has sent a very dangerous signal to the world that its ultimate policy goal is to secure as much of the market as possible for European citizens."

One major international business group told Insider that the row had cast a "cloud of uncertainty" over the international effort to inoculate the world's population against COVID-19.

"The signals we've received from Brussels suggest that officials are alert to the concerns we expressed on behalf of global business last week, but the regulations leave open a risk that shipments will be blocked - and, in doing so, have cast a cloud of uncertainty across the global vaccine distribution effort," John Denton, secretary-general of the International Chamber of Commerce, which last week warned the European Commission over the dangers of its approach to vaccine supply, told Insider.

So could the EU's move be an opening salvo in what could turn into a much wider global vaccine war?

Here are the three scenarios that industry groups are most concerned about.

Countries impose export controls on vaccines

There is a real danger that other countries may now introduce export controls on vaccines produced within their borders to protect supplies for their own populations. The manufacturing of vaccines is geographically concentrated in very few countries, such as India. Any decision by one of these manufacturing countries to introduce export controls themselves would severely disrupt the global supply of vaccines.

Some countries have already demonstrated their tendency to hoard their supplies during the pandemic - not least the US, which last year said it would seize exports of medical equipment including masks and gloves to determine whether it should be kept in the country to fight the pandemic.

Countries impose export controls on manufacturing supplies

Some of the ingredients commonly used in vaccine production are geographically concentrated in only a few countries. One example is an extract from Chilean soap bark tree, a product commonly used in vaccines that boosts the body's immune response to the jab. It is expected to be used in at least one COVID-19 vaccine produced by Novavax, the Atlantic reported.

The world embarks on a retaliatory trade war

Protectionism has already reared its head during this pandemic. For example, Turkey was accused by Spanish officials of seizing medical ventilators using parts from China that were destined for Spain, and Tunisia last year accused Italy of seizing a shipment of medical alcohol bound for the country.

The fundamental problem is that there is not enough manufacturing capacity to vaccinate the entire global population this year or even next year. A report published by UBS found that - at current rates - only 10% of the world will be immunized against COVID-19 by the end of this year, rising to just 21% at the end of 2022.

That limited supply will almost exclusively be used to immunize wealthy countries' populations, which have bought almost the entire forward supply of vaccines. But a nationalistic approach will carry an enormous public health cost by prolonging the pandemic and increasing the chance of a new, vaccine-resistant strain emerging.

It would also carry a high economic cost. Last week, a report commissioned by the ICC found that unequal distribution of the COVID-19 vaccine would cost the global economy $9 trillion by extending the pandemic. Half of that cost would be borne by rich countries.

The fear is that in a global vaccine war, all sides would ultimately lose out.