【明報專訊】Hong Kong has seen new local cases of COVID-19 variants repeatedly, while Singapore has considerably tightened its anti-pandemic measures due to new clusters of infection related to COVID-19 variants. The launch of the Hong Kong-Singapore air travel bubble, originally scheduled for the end of this month, might fall through once again. With the variants wreaking havoc, the pandemic is out of control in India, posing a major challenge to anti-pandemic efforts around the globe. The government of Singapore has announced the tightening of entry restrictions. The Hong Kong government should review hotel quarantine as well as testing and specimen collection arrangements as soon as possible and be more decisive in taking the ''nuclear'' option of grounding aircraft. Meanwhile, mandatory quarantine and isolation arrangements should be toughened to prevent the spread of COVID-19 variants in communities in the short term.