The Swiss Federal Office of Public Health (FOPH) says the number of imported Zika virus cases has reached 16 since March, according to a Le Matin report (computer translated), although officials say the case count could be higher because of asymptomatic cases.

Image/CDC
Image/CDC

All the cases had previously traveled to areas where there is ongoing Zika transmission–in regions including but not limited to South America, Central America and the Caribbean.

FOPH notes that in seven cases, they know where the infected people stayed last. Two were returning from Brazil and Colombia, one of Bolivia, one of Guadeloupe and Ecuador.

In South Korea, local media reports that a Korean woman has been diagnosed with Zika after working in Vietnam.

Vietnamese health officials say the 25-year-old woman contracted the virus sometime during the one month she was in the country working. She returned to South Korea last week.

This is the fourth Zika patient that has been confirmed in South Korea.

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