China intensified its checks on people and goods arriving from Singapore on Thursday, as an outbreak of the Zika virus was confirmed to have spread to at least one person in neighboring Malaysia. Authorities in Singapore said they had detected 151 people with the Zika virus, including a second pregnant woman, as of Thursday. The government said earlier that half of the 115 cases reported previously were foreigners, mainly from China, India and Bangladesh, many of them among the thousands of migrant workers, and most had recovered. “Our best defense is to eradicate mosquitoes and destroy breeding habitats, all over Singapore,” Prime Minister Lee Hsien Loong posted on his Facebook page. Singapore is the only Asian country with active transmission of the mosquito-borne Zika virus.