For those of you who are just arriving back at Ocean Reef, New World Screwworm larvae were positively identified in Key deer and several other animals on Big Pine Key in late September 2016.  Screwworms are the larvae (maggots) of a fly that were eradicated from Florida over 50 years ago and from the United States over 30 years ago.


     There is a tremendous amount of information about this at the following website:  You can also sign up for daily updates at this website.  I did and have found the information here fascinating.


So here are just the basics:  The screwworm fly lays her eggs around the edges of an open wound or less frequently the mucous membranes (eyes, ears, nose, etc.) of any warm blooded animal. Humans can be affected but this is rare due to our better hygiene. The eggs hatch into larvae (maggots) which then burrow into the surrounding tissue as they feed. This burrowing (“screwing”) behavior is how they got their name.  When mature, these larvae drop off onto the ground, pupate, and eventually turn into adult flies. The larval stage causes extensive tissue damage which can lead to death if left untreated.  If caught early it is very treatable and rarely fatal.


     The New World screwworm has potential to be devastating to the livestock industry across the United States.  In our endangered Key deer, more than 130 deer have been euthanized or died as a result of this infestation.  That is estimated to be between 12-15% of the existing population. So far the screwworm flies have only been identified from Big Pine Key south to Sugarloaf.


     To prevent the spread of New World screwworm multiple state, local, and federal agencies have come together to assist in eradicating this pest from the Florida Keys. 


     On Oct. 3rd, 2016 the USDA and the Florida Department of Agriculture and Consumer Services established an Animal Health Check Zone and a quarantine area extending from the southern boundary of Key Largo (MM 91) south through Key West (MM 0).  Many of you have seen this interdiction station at MM 106 oceanside. 


     So how does this affect residents and visitors of Ocean Reef:


1)     If you travel with your pets into the Keys, on your drive back north you will be required to stop at the Animal Health Check Station at MM 106 oceanside.  The Animal Check Station Staff will ask you about your pet’s origin (where you have traveled from). If you have not entered the quarantine area south of MM 91 your vehicle will be released.  If you have traveled south of MM 91, they will ask you about any signs of screwworm in your pet.  If there is no evidence of screwworm, you may be given a Certificate of Inspection and your vehicle will be released. This process should take about 5 minutes.


2)     All livestock (horses, pigs, etc.)  heading north out of the Keys should have an Official Certificate of Inspection and proof of treatment against screwworm within 72 hours prior to movement out of the zone.  If no certificate was obtained the animals will be inspected and treated at the checkpoint.  If any animals are suspected of being infected with screwworm, they will be quarantined back to their origin for follow up and treatment. This should not affect too many of us at Ocean Reef.


3)     For pets (non livestock) traveling out of the Animal Health Check Zone by boat or airplane a Health Certificate is recommended.  There is no mandatory animal inspection.


     Two states (Georgia and Utah) have changed their requirements for animal entry into their states since the screwworm quarantine has been put in place. I suspect more states will follow their lead and tighten their requirements in the future.


Georgia Department of Agriculture:


        For those animals leaving the Florida Keys quarantine area with their final destination to the state of Georgia (those staying for a period of time not just transiting Georgia without stopping) a Certificate of Veterinary Inspection will be required. Animals can be inspected at the Animal Health Check Station (MM 106) and if free of screwworm a Certificate will be issued by one of the veterinarians on site. Alternately this can be done by me at the Grayvik Animal Care Center.

      Dr. Robert Fernandez with the Florida Department of Agriculture recommends that this be done within 72 hours of travel to Georgia.


Utah Department of Agriculture:


     For those animals leaving the Florida Keys with their final destination being the state of Utah:  all livestock and pets traveling from outside the quarantine area must be examined for signs of New World screwworm and treated appropriately for screwworm by a veterinarian prior to travel to Utah.




    To try to clarify these statements, I spoke with Dr. Barry Pittman the Utah State Veterinarian about Ocean Reef’s location in reference to the quarantine zone. He said that if you travel with your pets into the quarantine zone south of MM 91 and return home then you do not need a special permit to enter Utah.  Your pet will need a Certificate of Veterinary Inspection issued within 72 hours of travel, but will not be required to be treated for screwworms prior travel.


     So when it is time for you to travel out of state or out of the country with your pet be sure to check with the Department of Agriculture of your final destination to see about their requirements for entry. I suspect these requirements will change depending on what is happening here in the Keys.


    As a result of my conversations with the Florida, Georgia, and Utah Departments of Agriculture, I think it will be prudent to have a Certificate of Veterinary Inspection (Health Certificate) done within 72 hours of travel even if not specifically mandated by your final destination.  It also makes sense from a scientific and biological standpoint and gives us our best chance of not introducing screwworm anywhere else in the country. Again these Certificates can be done at the Inspection Station at MM 106 or we can issue them at the Grayvik Animal Care Center.


    I will try to update everyone as I get new information from the multiple agencies involved with the fight to eradicate the New World screwworm from the Florida Keys. If you have any questions go to or don’t hesitate to call me or my staff at the Grayvik Animal Care Center.


    So check your pets daily for signs of screwworm, such as open wounds, maggots, or eggs. If you suspect your pet has signs of screwworm contact us at Grayvik Animal Care Center, or your veterinarian.   



Thank you and welcome back!

Dr. Mae Wasson

Grayvik Animal Care Center/ORCAT