Nov 16 (Reuters) - More than 50% more people died in Bulgaria than usual during September, official data showed, making the European Union"s least vaccinated country its hardest-hit during a resurgence of coronavirus cases over the late summer. According to a Eurostat report which compares additional deaths with pre-pandemic levels, Bulgaria had the highest excess mortality in the EU, followed by Lithuania, Greece and Romania - all over 30%.Since September, the pandemic has further worsened in eastern Europe, with Bulgaria hitting record numbers of daily coronavirus deaths in recent weeks. read more According to a Statista report, Bulgaria had as of last week administered just 44 vaccine doses per 100 people - the lowest rate of any European country. It has one of the highest COVID-19 death rates per capita in the world, as does Romania with the EU"s second lowest vaccination rate, and where the elderly are especially affected. read more Excess deaths across the European Union as a whole rose to 12% in September, said Eurostat, climbing rapidly over the late summer from a low of 5% in July. The region had peaked at 40% excess deaths in November 2020. Among the countries with the lowest excess mortality in September were Sweden and Belgium. Belgium in particular faced high death rates earlier in the pandemic. Reporting by Sarah Morland Editing by Peter Graff Our Standards: The Thomson Reuters Trust Principles.