World Rugby confirmed on Thursday that the decision had been made with the Hong Kong Rugby Union and Sport Singapore to reschedule the fixtures in response to "continued health concerns relating to the Novel Coronavirus (COVID-19) outbreak".
"The health and safety of our players, fans and everyone working on the event is always our highest priority," World Rugby said in a statement.
"This prudent decision has been taken in order to help protect the global rugby community and the wider public and was taken based on the World Health Organisation and relevant public authority travel and health guidelines.
"The decision is fully supported by stakeholders, including unions and commercial partners."
Hong Kong was due to host the event between 3-5 April, but that has now been switched to 16-18 October.
Meanwhile, the round in Singapore initially scheduled for 11-12 April will now take place on 10-11 October.
World Rugby additionally confirmed that "Hong Kong and Singapore will host HSBC World Rugby Sevens Series 2021 tournaments as per usual in April".
Multiple sporting events have been impacted by the outbreak of the coronavirus, which has killed more than 1,300 people. There have been almost 60,000 cases of the virus in China and more than 400 more confirmed across 24 countries.
On Wednesday, the 2020 Chinese Grand Prix - scheduled for April 19 - was postponed, while the Formula E race in China and World Athletics Indoor Championships have also been called off.
Chinese domestic football is postponed at all levels.