ATHENS — He's said it before and now a noted Greek-American doctor is beating the drum again with a warning Greece could be hit with a fourth wave of COVID-19 although vaccines are beating back the pandemic slowly.

Dr. George Pavlakis said the Coronavirus nevertheless could resurge after the summer if people keep ignoring what's left of health measures with the essential lifting of an already lenient lockdown, many even shunning masks and not staying a safe distance apart.

He was speaking to SKAI radio and advised the government to further speed the vaccination campaign that so far has inoculated only about 20 percent of the population, some 70 percent needed to push back the pandemic – which he said should be 80 percent.

He also recommended more diagnostic tests and better contact tracing and said people should not go on vacation unless they have received at least one of two required doses of vaccines, apart from the single-shot Johnson & Johnson from the US.

Senior investigator and head of the Human Retrovirus Section at the American National Cancer Institute, he earlier told Mega TV that people heading to islands the government wants to make free of the Coronavirus haven't been checked right. 

“The virus will come back to bite us if we disregard it. Even though we have the standards, the information, we are opening up without abiding by any standards and this is evident all around you,” he said.