The European Union’s health agencies on Tuesday said a mixing and matching of approved Covid-19 vaccines could be used for both the initial courses and booster doses, as the region battles rising cases ahead of the holiday season.
Evidence suggests that the combination of viral vector vaccines and mRNA vaccines produces good levels of antibodies against the coronavirus causing Covid-19, the European Medicines Agency (EMA) and the European Centre for Disease Prevention and Control (ECDC) said in a statement.
The use of two different Covid-19 vaccines for the first and second doses of a primary (initial) course is known as “heterologous primary vaccination”. Using a third dose of a different Covid-19 vaccine as a booster three to six months after a primary vaccination course is called “heterologous boosting”.
The EMA-ECDC statement noted that, “While research is ongoing to provide more evidence on long-term safety, duration of immunity and effectiveness, the use of heterologous schedules may offer flexibility in terms of vaccination options, particularly to reduce the impact on the vaccine rollout should a vaccine not be available for any reason.”
Their endorsement came a day after a major study on Monday found that a first dose of AstraZeneca or Pfizer-BioNTech shots followed by a Moderna vaccine nine weeks later induced a better immune response.
The US has given the green light to mix-and-match, while the World Health Organization (WHO) is also assessing the approach.
Longevity of protection offered by vaccines has been under scrutiny and the world is scrambling to trace the Omicron variant as governments are imposing fresh restrictions. Official rollout of vaccines for 5-11 year olds will start next week in Europe.
The latest EMA and ECDC recommendations are also meant to help EU member states with their own vaccination campaigns before any formal EU-wide approval as the health agencies continue studying data on mixing vaccines.
WHO says vaccine mandates should be ‘last resort’
The endorsement came as the WHO’s Europe branch on Tuesday cautioned against making Covid-19 vaccines mandatory, while urging better protection of children, among whom cases are high.
Regional director Hans Kluge said compulsory vaccines should be “an absolute last resort and only applicable when all other feasible options to improve vaccination uptake have been exhausted”.
Noting that mandates have increased vaccine uptake in some cases, Kluge said these were “context specific”, and added that the effect mandates may have on “public confidence and public trust” must also be considered.
Europe is battling a fierce surge in the pandemic, with the WHO registering 120,000 Covid-related deaths on the continent since November 23 when it warned of up to 500,000 more deaths by March 2022.
Children have highest infection rates
The regional health bloc also noted that the number of cases had increased “across all age groups, with the highest rates currently observed in the five to 14 years age group.”
“It is not unusual today to see two to three times higher incidence among young children than in the average population,” Kluge told a press conference.
“The health risks extend beyond the children themselves,” Kluge added, noting that children risk passing the infection to parents and grandparents in the home.
“Vaccinating children should be discussed and considered nationally,” he said.
The WHO’s European region comprises 53 countries and territories, including several in Central Asia.
The organisation also expressed concern about rising cases of the recently discovered Omicron variant of the virus, but stressed that the fight should still be focused on the currently dominant Delta variant.
“The problem now is Delta and however we succeed against Delta today is a win over Omicron tomorrow, before it eventually surges,” Kluge said.
(FRANCE 24 with AFP and REUTERS)