The EU's campaign to vaccinate Europeans against COVID-19 has got off to an uneven start in what will be a marathon effort to administer shots to enough of the bloc's 450 million people to defeat the viral pandemic.
In one mishap, eight workers at a care home in Stralsund on the north German coast were injected with five times the recommended dose of the vaccine developed by Pfizer and BioNTech. Four were hospitalised.
"I deeply regret the incident. This individual case is due to individual errors. I hope that all those affected do not experience any serious side effects," district chief Stefan Kerth said on Monday.
In southern Germany, officials had to send back about 1,000 doses after finding they had been transported in cool boxes typically used for picnics or camping trips that failed to keep the vaccine cold enough.
The EU vaccination drive kicked off at the weekend, with health workers and residents of care homes across the bloc among the first to get the shots from Pfizer, which must be stored at ultra-cold temperatures.
In Italy, meanwhile, some politicians complained that Germany - the EU's largest member state and home to BioNTech - may be getting more than its fair share of shots.
The EU is due to receive its first 12.5 million doses of the Pfizer vaccine by New Year's Day, with distribution of 200 million doses across its 27 member countries to be completed by next September. The vaccine course requires two doses.
A spokesman for Pfizer declined to comment on specific schedules or whether the timeline indicated by the Commission represented a delay. "Our timelines are aspirational and can shift based on capacity and manufacturing timelines," he said.
Talks are under way to agree on the delivery of an optional further 100 million doses under the contract sealed with the two companies, the EU said.
The initial glitches highlight the challenge in rolling out the vaccine while regulators consider approving other vaccines, including from Moderna and AstraZeneca, which are easier to transport and store.
The rollout of the Pfizer shot in the United States has been slow, putting the government's target of 20 million vaccinations this month in doubt, as hospitals navigate preparing the previously frozen shots for use, finding staff to run clinics and ensuring proper social distancing.
As well as being the first COVID-19 vaccine to be delivered across the EU, the Pfizer shot is particularly tricky to handle. For long-term storage it needs to be deep frozen at about minus 70 Celsius (minus 94 Fahrenheit).
It can be defrosted for a few days before being used, but even then must be kept chilled at between 2C and 8C.
In southern Germany, officials said they would not use some shots after temperature trackers in cool boxes showed they may not have been kept cold enough.
"There were doubts as to whether the cold chain was maintained at all times," said Christian Meissner, district administrator in the Bavarian town of Lichtenfels.
"BioNTech said that the vaccine was probably okay, but 'probably okay' is not enough," he told Reuters TV.
The lapse happened after the doses were handed over to the local authorities. BioNTech declined to comment.
In Spain, delivery of a new batch from Pfizer was held up by a day to Tuesday due to a temperature issue that has now been resolved, Health Minister Salvador Illa said.
Maria Asuncion Ojeda, a resident at Madrid's Ballesol Parque Almansa nursing home, was still delighted to be an early recipient of the Pfizer vaccine.
"I wanted to do it because it's the only way we can solve this problem," the 87-year-old said on Monday, a day after Spain began vaccinating care-home residents and their staff.
The EU is distributing jointly procured vaccines on a pro-rata basis to the 27 member states based on their populations, while some European countries have also made their own deals to buy extra doses separately.
In Italy, some politicians said Germany appeared to be getting more than its fair share, at least during the highly symbolic initial rollout.
"The accounts don't add up," Italian virologist Roberto Burioni said on Twitter, pointing to reports in Germany that first-day deliveries had totalled more than 150,000 doses while other EU countries got just 10,000.
An official familiar with vaccine distribution in Germany said that each of the 16 German federal states had received 10,000 doses of the Pfizer vaccine ahead of the weekend start of the inoculation drive.
An Italian reporter asked about the supplies at a German government news conference. An official from the German health ministry replied that Berlin had signed a separate deal for 30 million extra doses of the Pfizer vaccine.