The number of cases of the mosquito-borne Zika virus continued to gradually increase last week, with new cases reported in Collier, Palm Beach and Orange counties, according to the state Department of Health website. 

As of Monday, the state reported 87 Zika cases this year, up from 84 a week earlier.

All but two of the cases are considered “travel” related --- generally meaning people were infected elsewhere and brought the disease into the state. The other two cases were classified as having “undetermined” origin, with both of those cases involving people in Miami-Dade County. 

The disease, which caused major concerns in 2016, is particularly dangerous to pregnant women because it can cause severe birth defects. 

Collier County has had the most Zika cases this year, with 33, followed by Miami-Dade County at 24.

They are followed by Orange County at 11 cases, Broward County at six cases, Palm Beach County at five cases and Osceola County at three cases. Lee, Hillsborough, Pinellas, Hernando and Walton counties have each had one case.

Copyright 2020 Health News Florida. To see more, visit .