Aug. 15 (UPI) -- Paraguay has declared a health emergency after confirming its first measles outbreak in a decade, with five unvaccinated children infected in the San Pedro department.

Health authorities said the outbreak may be linked to foreign visitors from countries with active cases and acknowledged that vaccination rates in that part of Paraguay are below recommended levels.

The outbreak began with a 5-year-old boy who was hospitalized with pneumonia, fever, cough and a skin rash. By Aug. 7, three other children in the same household had tested positive, followed by a fifth case three days later, according to the Health Ministry.

All five patients remained under observation during the incubation period, estimated at seven to 18 days.

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