05/18/98 - Bradenton and Umatilla Mediterranean Fruit Fly Infestation Update - DACS

Provided by Dr. Marion Fuller
Florida Department of Agriculture and Consumer Services (FDACS)

Report dated 05/17/98

Bradenton

Infested area: The fly count (as of this morning) is around 170, with 30 of these caught in a single sticky panel. We have also detected larvae at several (don't have count) sites. Adult flies have been found in an area that encompasses four square miles, with a regulated area (quarantine) that covers about 24 square miles. (map will follow tomorrow).

In response to the current detections, and consistent with response protocols, traps are being deployed in the core area of 100/sq. miles. For each square mile surrounding the core, trap density is 50/sq mile. Working outward, for each square mile, there are then 25/sq. mile, 20/sq. mile, and 10 /sq mile. This allows us to determine the extent of the infestation. As traps are deployed counts may change rapidly, as may the treatment and quarantine areas.

In response to these detections, the Environmental Protection Agency (EPA) has approved four applications of ground bait treatments in the four square mile "core" area; however, at this time, actual treatment is limited to an area of about two square miles (this will be easier to follow with the map being sent tomorrow). Should any flies be discovered in the regulated area outside the "core" (four sq mi) area, EPA has also approved application to the affected host material within a 200 meter radius surrounding the fly detection. In addition to the ground bait treatments, United States Department of Agriculture (USDA) and FDACS are gearing up for sterile fly release, as soon as practicable.

In addition to the measures above, fruit stripping at fly sites is being used.

FYI: This infestation is somewhat different from that in Umatilla. Some background on this area: It is across the water from Snead's Island which was treated last fall. Trapping density has remained heavy (at least 25/sq. mile) in Bradenton, through April 17th of this year, when eradication was officially declared. At that time trap density decreased to about 10/sq. mile for about two weeks, and dropped to about 5/sq. mile two weeks ago. Throughout that time, no Medflies were detected in any of the traps. It is something of a puzzle - given the trapping density, and life cycle of the fly (at least a 21 day life cycle) it is unusual (and unfortunate) that there were no detections prior to this week.

A public meeting was held Saturday at the Manatee High School. USDA and FDACS gave an overview of the current infestation, basic information on the Medfly itself, efforts to exclude introduction, measures taken to effect eradication, and measures being taken to prevent spread of the Medfly out of the area. It was made clear that there was no intention of using aerial applications, and that sterile flies would be released as soon as practicable. Afterwards, citizens were provided an opportunity to ask questions.

About 30 citizens attended. Informational material was available from USDA/FDACS, as was information from SCRAM (Sarasota and Manatee Citizens Rallying Against Malathion). While several questions were asked, most speakers preferred to make comments. Comments included the following:

Comment - FDACS/USDA hasn't done enough education/communication. Done more than before (Tampa), but still need more education of citizens - especially regarding actions that citizens can take to reduce risk for Medfly reproduction and movement out of the area (e.g. fruit stripping, not moving fruit out of the area, not composting certain fruits/ vegetables, etc)
[Response] - Basic information is provided to property owners when permission is sought for ground bait treatments on private property. FDACS and USDA are working with the media to get accurate coverage of the situation as it develops. The group represented by the commenter has worked w/FDACS to develop flyers, on these and other topics. This information along with other documents and handouts were available at the public meeting. Media coverage has been fairly broad also.
Comment - Request for more dumpsters, in which properly bagged fruit can be disposed.
Comment - Request/comment that FDACS do more fruit stripping for citizens.
[Response] - At this time, resources are extremely stretched - while state/federal employees are stripping those areas of a fly find, proper priority is to get ground bait applications out.
Comment - General strong support for sterile release.
Comment - Frustration that sterile release couldn't be started immediately. State was aware of this possibility since Tampa outbreak - why aren't sterile Medflies being released as preventative measure? Apparent lack of commitment from FDACS for sterile program.
Response Unfortunately, funding isn't currently available for ongoing sterile release program.
Comment- Opposition for malathion in general. Malathion isn't safe. State has mislead the public saying it is.
Comment - Support for California program - particularly continual release of sterile Medflies as a preventative measure. Florida program should be more like California program.
[Response] - This was occasionally mistakenly portrayed as having no malathion component. Also, there seemed to be little realization or acknowledgement that California was not able to implement sterile release as preventative measure until California legislature provided ongoing funding source.
Comment - This area contains a cluster of childhood cancers - is a particularly sensitive area - malathion should not be used.
[Response] - Department of Health (DOH) personnel were present, we will follow up on that statement.
Comment - Government personnel decent folks, trying to do a good job, don't always have resources necessary. Citizens should work with them. Common goal - no one wants Medfly in area.
- Agriculture industry mischaracterized as not supporting sterile release. Does support sterile release as an option. More appropriate in some areas than others. Each infestation should be handled according to local community needs/desires.
Comment - Congratulations to DACS for listening to citizens requests, and allowing citizens to determine if ground bait treatment will or won't be made on their property.
[Response] - I don't believe this is actually "new" - however, it may not have been appreciated during the Tampa program, where misinformation/misunderstanding was not an unusual occurrence.
Comment - Conversation with EPA employees indicates that EPA has determined malathion is a carcinogen.
[Response] - SCRAM is distributing a flyer that states "EPA has labeled Malathion as a likely carcinogen and shows a significant incidence of tumors in their study." Neither FDACS nor DOH has been provided this information from EPA. EPA personnel at the meeting were not able to determine the source of this claim. It is my understanding that the carcinogenicity status is still under review; that pathologists are reviewing the slides.
Comment - There is a lawsuit in California involving a claim that aerial application caused physical harm to an individual. Affidavits are available to substantiate this claim.
Comment - About 25% of the uses of malathion are for home/garden uses. Rates usually higher than rate being used to treat Medfly.

So far, citizens have been allowing application of malathion to their property.

As before, DNA analysis will be run on the captured Medflies. Preliminary results should be available within about 7-10 days, definitive analysis takes a good bit longer. (Still awaiting final report on flies in Umatilla).

Environmental Monitoring: DEP determined that they did not need to take water samples of the Manatee River, given the size of the river (volume of water) and that this is a ground bait treatment. I believe USDA is sampling the River.

Heath Monitoring: DOH personnel received hotline training Friday afternoon. No report available at this time.

Umatilla

Fly count is about 1311, with the additional detections occurring within the current treatment area.

Aerial application took place over Saturday and Sunday. Saturday's application was delayed while equipment was recalibrated. A new batch of NuLure was used, with a slightly different viscosity than what was used last week. Several nozzles were recalcitrant, required replacement, which delayed the first helicopter about an hour or so. Subsequent helicopters were less a problem. A third helicopter was used, to help cut down the application time - consequently, application was completed around 12:30 pm. Sunday's treatment was less problematic, and was completed by about 8:30-9:00 am.

Enviromental Monitoring:
The lab has advised me of several sample results, previously reported in one of my updates, that need correction:
For 5/3/98 (post application samples) -
Palm Lake: 15 ppb
Geneva: 1.3 ppb
Gibson: 4.5 ppb
Yale: 1.2 ppb

New sample results:
5/3 Bay Lake: 62 ppb (first application, post sample)

Drift cards (second application)
5/11 Cresent Lake: below detectable levels (BDL) at waters edge; positive at 30 m out; BDL at 100, 150 m from water's edge; positive at 200 m from waters edge.

5/11 Bay Lake: Positive at water's edge and at 100 m, 150 m, and 200 m from waters edge. Sample at 50 meters was not available (card lost to circumstances outside the sampler's control).

5/12 Lake Yale: All samples below detection limits (water's edge, 50 m, 100 m, 150 m, and 189 m from water's edge.

Note: Bay Lake is a small lake, no public access. Drift cards have been positive, you may recall the second pre-application concentration of malathion was 1.1 ppb. There are fish in lake, and at this time no visual evidence of adverse effects (no fish kills, etc). We are working with the pilots to see what additional measures can be made to help identify this area from the air.

Health Monitoring: One additional call has come in reporting eye irritation/infection. Symptoms occurred about one week after the first application. DOH is following up with the caller and his/her physician, to determine if the bait application is causally related. There have been no calls/visits to the emergency room or hospital reported.

The Science Advisory Panel (this is the "bug" panel - made up of Medfly experts) will be meeting Monday and Tuesday to discuss the infestations in Umatilla and Bradenton, and formulate recommendations to USDA/FDACS regarding treatment options.

The Florida Helpline continues to receive calls from citizens in Tampa and Sarasota, opposing the use of ground bait applications of malathion. Some callers also voice their opinion that the information provided by the Health Department is inaccurate/misleading.

FDACS - Division of Plant Industy: Mediterranean fruit fly information
USDA APHIS: Mediterranean fruit fly information
UF/IFAS Fact Sheet ENY-809: The Mediterranean Fruit Fly
UF/IFAS Fact Sheet ENY-626: Mediterranean Fruit Fly: What Floridians Need To Know


The UF/IFAS Pest Alert WWW site is at: http://pestalert.ifas.ufl.edu/