Singapore authorities confirmed on Sunday that 40 people have been infected locally by the Zika virus, but most have fully recovered.
Singapore announced its first Zika infection in May, with the virus imported by a 48-year-old man who had traveled to Brazil. On Sunday, the Ministry of Health confirmed 41 locally transmitted cases of the virus.
The ministry said in a statement that the patients were "not known to have traveled to Zika-affected areas recently, and are thus likely to have been infected in Singapore. This confirms that local transmission of Zika virus infection has taken place."
Of the group, 34 people have recovered, while seven remain at Tan Tock Seng Hospital, the statement said.
The ministry named two residential districts of Singapore where the disease was transmitted and said that the bulk of those infected were foreign construction workers. The virus was mostly detected through tests on Saturday.
Among those still hospitalized is a 47-year-old Malaysian woman, identified by authorities as the first locally transmitted case.
Zika has mild effects on most people, but can be fatal for unborn children. Infection during pregnancy can result in babies with small heads — a condition called microcephaly — and other brain defects.
(With inputs from AP)