"We are at the beginning of the second wave, I think in two or three weeks we will know exactly what is happening now", Hufert said.
Although the spread of the disease has largely subsided from its initial peak in early April, daily new COVID-19 cases broke the 1,000 mark on Friday.
Hufert said that his estimation is based on probabilities derived from the amount of international travel that the country has seen since it began lifting restrictions.
He added that although all persons arriving in Germany are currently required to undergo a coronavirus test at the airport, the study is "unreliable, as a negative result indicates no traces of the virus within 72 hours".
"It is not a fact that these traces will not appear in a few days, provided that the infection occurred, for example, on the day of departure", the virologist said.
Germany has yet so far escaped a steep rise in new infections upon easing of restrictions, a trend that has become somewhat common in many countries around the world. The Robert Koch Institute, the country's de facto COVID-19 tally keeper, has counted over 212,000 cases and 9,232 deaths as of Tuesday.