You proving our point...there will always be an uptick after you reopen after doing a massive lockdown.
Vietnam has like 3 cases. But best believe when they open up international travel they will have an uptick.
If you keep R-naught below 1 you will continue seeing a reduction in cases.
Denmark for example saw an uptick to between 0.6 and 0.9 after they re-opened schools.
Not sure about the number for Germany but they will adjust it back down again if required.
The reproduction depends not only on social distancing measures and hygiene but also on how religiously the population at large follows the rules.
In traditionally command driven societies mass compliance will be easier to attain.
"According to
a new analysis from Denmark's infectious diseases agency SSI, the so-called reproduction rate has increased from 0.6 to 0.9, still below the crucial figure of 1, which means that each infected person on average infects on average one other over the course of their illness"
https://www.thelocal.dk/20200430/reopening-denmark-has-increased-rate-of-infection-spread-ssu
There is a lot of scope for compliance and creative working before just deciding to "let it rip".
As Merkel explains here you need to track and adust based on R-naught movements.
As she has also stated it relies on everyone in the country to do their part.
"“Germany has an excellent health system, perhaps one of the best in the world... But our hospitals would be completely overwhelmed if too many patients were admitted in a short time suffering from a severe coronavirus infection.”"
"
“It is up to each of us.
We are not doomed passively to accept the spread of the virus,” she said. “We have a remedy: we have to keep a distance from each other out of respect."
Coronavirus is Germany's biggest challenge 'since Second World War' Angela Merkel says