Covid seems to go in four-month waves
We know that each country's Covid reporting is flawed - some over-report, some under-report, for whatever reason. It seems highly unlikely that similar and neighbouring countries (Austria v Switzerland; Czah Rep vs Slovakia etc) would show such large differences. Also, some countries - like NZ - have suppressed real numbers with extreme meansures, but they are just delaying the problem.
But if you add up world totals, then all the under- and over-reporting should largely cancel out and the real trends are probably fairly reflected.
Worldometers.info prepare exactly such charts, it is pretty ...