Countries across Europe are scrambling to accelerate coronavirus vaccinations and outpace the spread of the more infectious delta variant, in a high-stakes race to prevent hospital wards from filling up again with patients fighting for their lives.

The urgency coincides with Europe’s summer holiday months, with fair weather bringing more social gatherings and governments reluctant to clamp down on them. Social distancing is commonly neglected, especially among the young, and some countries are scrapping the requirement to wear masks outdoors.

Incentives for people to get shots include free groceries, travel and entertainment vouchers, and prize drawings. The president of Cyprus even appealed to a sense of patriotism.

The risk of infection from the delta variant is “high to very high” for partially or unvaccinated communities, according to the European Centre for Disease Control, which monitors 30 countries on the continent. It estimates that by the end of August, the variant will account for 90% of cases in the European Union.

“It is very important to progress with the vaccine rollout at a very high pace,” the ECDC warned.

The World Health Organization is also concerned. The variant makes transmission growth “exponential,” according to Maria Van Kerkhove, its technical lead on COVID-19.

Daily new case numbers are already climbing sharply in countries like the United Kingdom, Portugal and Russia.

In the U.K., cases of the delta variant have increased fourfold in less than a month, with confirmed cases Friday up 46% on the previous week.

Portuguese health authorities this week reported a “vertiginous” rise in the prevalence of the delta variant, which accounted for only 4% of cases in May but almost 56% in June. The country is reporting its highest number of daily cases since February, and the number of COVID-19 patients in hospitals has surpassed 500 for the first time since early April.

Reports of new infections in Russia more than doubled in June, topping 20,000 per day this week, and deaths hit 679 on Friday, the fourth day in a row that the death toll set a daily record.

Still, “no one wants any lockdowns,” said Kremlin spokesman Dmitry Peskov at a briefing, although he admitted that the virus situation in a number of Russian regions is “tense.”

In some countries, the virus is spreading much faster among younger people. In Spain, the national 14-day case notification rate per 100,000 people rose to 152 on Friday. But for the 20-29 age group, it shot up to 449.

Those numbers have triggered alarm across the continent.