Sarajevo, 16 August 2021 (dpa/MIA) — Starting Thursday, Serbia will start offering coronavirus vaccine booster shots to everyone over age 70, those over 60 who live in an old people's home, health care workers and immunocompromised adults. People in these vulnerable groups will receive a notice from the authorities of their eligibility and the next steps to take, the government in Belgrade said on Monday. The third vaccination can be given from the 180th day after receiving the second dose. Serbia started vaccinations in December. The Balkan country has used jabs from China and Russia on a large scale, as well as vaccines from Pfizer BioNTech and AstraZeneca. Despite plenty of supplies, the unwillingness among many Serbians to get the shots has proved to be a major obstacle. Only 40 percent of the population is fully vaccinated so far.