The Danish Ministry of Foreign Affairs has raised the prospect of issues with foreign travel for people with the mixed vaccination status and has gone as far as to advise those with autumn travel plans that the “most certain” way of ensuring smooth travel is to delay the second jab.
Around 50,000 people in Denmark who were vaccinated against Covid-19 with the one-dose jab from Johnson & Johnson are set to be offered a booster vaccine in October.
But the Foreign Ministry has warned that people who receive the booster – which will be a dose of the Moderna or Pfizer vaccines, rather than Johnson & Johnson – risk running afoul of travel restrictions on trips to other countries in the intermediate term.
That is because rules on double vaccination with mixed jabs vary between countries, while anyone vaccinated with a single dose of Johnson & Johnson is uniformly considered fully vaccinated.
“It’s not certain that countries will have addressed this until after the autumn holidays and you could therefore risk not being able to enter if you have received jab number two,” Erik Brøgger Rasmussen, director of the ministry’s organisation and citizen service (Borgerservice), told broadcaster DR.
“It is clear that if you, from a health point of view, want to be on the safest side, you should hurry up and receive the (booster) jab that is now being offered,” Rasmussen said.
“But if you want to travel during the autumn holidays, the most certain model is probably to wait to have the second dose,” he added.
The Danish Health Authority has recommended those vaccinated with Johnson & Johnson to be offered an mRNA (Pfizer or Moderna) booster from October 1st, citing new data from the national infectious disease agency State Serum Institute (SSI).
According to SSI, “the level of efficiency against being infected with new coronavirus decreases, especially due to the Delta variant,” is lower with the J&J vaccine than with two-dose vaccines.
“We also expect that the effect will decrease further in the near future,” the agency adds.
The single-dose Johnson & Johnson vaccine is universally recognised as giving full vaccination status.
But the presence of more than one type of vaccine in vaccination records could throw recognition of vaccination status into doubt, Rasmussen explained.
“Each individual country must decide whether it will recognise one vaccination with Johnson & Johnson plus one vaccination with an mRNA (vaccine) or whether you might need, for example, two doses of the mRNA vaccine for it to be valid as full vaccination,” he said.
The departmental director said that the ministry’s citizen service was working to gather information for its travel guidelines, confirming whether individual countries accept cross-vaccination including Johnson & Johnson.
“We are working on this but authorities in the countries we are reaching out to might not have addressed it yet and it is therefore not yet possible to put a date on when (guidelines) will be ready,” he said.
The UK recently confirmed that mixed vaccine doses received in Europe are accepted as full vaccination, provided the second dose was received at least 14 days ago.
But the UK government’s guidelines state that mixed doses are accepted only with vaccines where two doses are needed for a full course, and do not make any mention of boosters. So while anyone jabbed with J&J in Denmark could be accepted to travel in theory, the concern would be that British authorities may interpret the booster shot as just one jab.