Six members of the European Union have expressed concern over how the EU is distributing Covid-19 vaccines after AstraZeneca once again lowered its delivery targets.

Austria, Latvia, Czech Republic, Bulgaria, Croatia, and Slovenia have complained to the European Commission about the disproportionate distribution of vaccines in the EU countries. 

It was initially agreed that vaccines procured by the EU would be distributed in proportion to the country's population. But some countries have introduced flexibility to the system so that they can get more of a specific vaccine, depending on price and terms of service. The European Commission responded to the letter, stating that vaccine distribution is a transparent process.

According to media reports, Bulgaria, for example, preferred to receive fewer vaccinations from Pfizer and BioNTech. As a result, other EU countries were able to purchase surplus vaccines from Pfizer and BioNTech.

According to the European Center for Disease Prevention and Control, Bulgaria and the other signatory countries that signed the letter are among the EU that received the least amount of vaccines.

They are concerned that some EU countries will be able to achieve herd immunity in a few weeks, while others will lag far behind.

Their complaint follows news that AstraZeneca will not meet its targets in the coming months. The Swedish-British pharmaceutical firm has confirmed that it will ship 30 million doses to the EU by the end of the first quarter and another 70 million doses in the second quarter.