Puerto Rico declares public health emergency as dengue fever cases rise | 27 March 2024 | Puerto Rico has declared a public health emergency as the number of dengue fever cases continues to rise. So far this year, there have been 549 cases reported with the plurality occurring in San Juan, according to the island's health department. There has been a 140% increase this year in cases from Jan. 1 to March 21, compared to the same period last year, the department said. The public health emergency order will remain in place for 90 days.