Countries including the U.K., Australia and Taiwan have issued travel advisories for tourists to Singapore after the city-state announced a further increase in Zika cases.
Singapore's Ministry of Health confirmed 15 more cases of locally-transmitted Zika virus on Monday, bringing the total number of affected to 56.
The new cases involved people who live or work in the Sims Drive and Aljunied Crescent area, and were detected from testings of potentially infected persons, according to a government statement.
The various travel advisories issued Monday warn expecting mothers to exercise caution and defer all non-essential travel to Singapore.
The Zika virus is transmitted mainly by Aedes mosquitoes, and has been linked to a rare birth effect, known as microcephaly, in babies whose mothers suffered from the virus while pregnant. Symptoms include fever, skin rash, red eyes, muscle and joint pain, malaise or headaches.