(Reuters) – The European Union’s drug regulator on Wednesday recommended that a booster dose of Johnson & Johnson (NYSE:)’s COVID-19 shot may be given at least two months after a first dose in people aged 18 years and older, as the bloc battles surging infections.

Omicron coronavirus is rapidly spreading around the world. The World Health Organization has warned that Omicron is a risky variant, but limited data is available.

The European Medicines Agency (EMA) said its recommendation to allow J&J booster doses follows data which showed the additional shot led to a rise in antibodies against the COVID-causing SARS-CoV-2 coronavirus.

The EMA said that a J&J booster dose may also be given after two doses of one of the mRNA vaccines from Pfizer-BioNTech or Moderna (NASDAQ:), as per its recommendation for mixing vaccines.

Following the death of at least one Omicron patient in the United Kingdom, the restrictions have been tightened in several EU member countries. The Omicron variant was discovered in South Africa and Hong Kong last month.

As Omicron’s high level of mutations could allow it to escape the protection of vaccines, Omicron is urging that booster doses be increased.

Pfizer BioNTech vaccines and Moderna have been approved by the EU watchdog. This is at least six months following a two-shot standard course. AstraZeneca’s booster doses are also being considered by the EU watchdog (NASDAQ:).