The couple has come all this way to get the Pfizer COVID-19 vaccine because it, unlike the four vaccines on offer in Russia, is approved by the World Health Organisation and the European Union.
"We have decided to get the Pfizer vaccine because, we think, it will allow us more frequent travels to Europe," the 50-year-old Grigoriev said.
Russia's Sputnik V COVID-19 vaccine, used in over 70 other states, has yet to be approved by the WHO, and no foreign-made vaccines have been approved in Russia.
Grigoriev and his wife are part of a new phenomenon which, much to the delight of the local tourism industry, first emerged in Serbia after it launched its COVID-19 inoculation campaign last December.
While countries across the Balkans struggled with hold-ups and shortages, Serbia was trumpeting its success at securing vaccines from a clutch of different suppliers, prompting an influx of 'vaccine tourists'.
Serbia approved vaccines made by Pfizer/BioNtech (PFE.N), (22UAy.DE), China's Sinopharm, AstraZeneca/Oxford (AZN.L) and Russia's Sputnik V for its inoculation programme, but so far only around 50% of Serbia's population received two shots, mainly due to strong anti-vaccine sentiment.
However, many foreigners, including Russians, have flocked to the Balkan country for a shot this year. According to official data, around 160,000 foreigners, mainly from the Balkans, have so far received their COVID-19 vaccines in Serbia.
Local and Russian tourist agencies reeling from the effects of the pandemic, sought to profit from vaccination tourism, said Predrag Tesic, owner of the Belgrade-based BTF agency.
"There are many businessmen among them (Russians) and they must get a vaccine to travel," he said.
A three- or four-day of stay in Belgrade would cost a Russian visitor between 500$ and 700$, Tesic said.
Russian firm Petrovax has said it requested approval for a vaccine manufactured by Sinopharm, although a decision has yet to be made. The Russian health ministry did not respond to a request for comment on whether other foreign manufacturers have submitted requests for approval.
Earlier this month, the Russian health minister said there were enough free vaccines available in Russia.
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