It comes after Edinburgh University epidemiologist Professor Mark Woolhouse said on Wednesday that Scotland should prepare for a third wave in winter.
Most health experts believe Covid-19 is “here to stay”, Prof Woolhouse told a conference on Wednesday, but the next wave will hopefully not be as severe as the previous ones.
Asked whether the Scottish Government is also modelling for a third wave in winter, Dr Caesar told BBC’s Good Morning Scotland on Thursday: "As we've talked about for many months now, this is a global issue.
"Eliminating this has to be done globally and is very, very unlikely, as Mark has said.
"The chances are that we will see recurring cases, and the timing of that, the amplitude of that – the numbers of cases that we will get and, of course, the effect on people in terms of significant illness and death – is something that there are a number of scenarios that we are looking at.”
A winter increase in cases is “fairly likely”, Dr Caesar said, but the NHS is attempting to make sure this does not happen before then.
“It is fairly likely that we will see more cases towards the tail end of the year,” he said.
"We’re just trying to make sure we have as much in place to make sure those don't translate into significant illness and, unfortunately death, before then, so that we're as prepared as possible.”
Prof Woolhouse told a virtual conference held by the Royal College of Physicians of Edinburgh: "Clearly we hope that the numbers of cases this summer will fall very low, that's likely, because we now have the vaccine rollout ... but most commentators would say that it's extremely unlikely that we're going to eliminate the virus.
“What we have to be prepared for is some kind of third wave next winter, that’s hopefully nothing like as severe as the wave we've had this winter.”