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Mount Hope Sprayed For Mosquitoes After Positive Zika Test

An Aedes aegypti mosquito, known to be a carrier of the Zika virus, acquires a blood meal on the arm of a researcher at the Biomedical Sciences Institute of Sao Paulo University in Brazil, Jan. 18, 2016.
Associated Press
An Aedes aegypti mosquito, known to be a carrier of the Zika virus, acquires a blood meal on the arm of a researcher at the Biomedical Sciences Institute of Sao Paulo University in Brazil, Jan. 18, 2016.

Mount Hope Sprayed For Mosquitoes After Positive Zika Test
Mount Hope To Be Sprayed For Mosquitoes After Positive Zika Test GUEST:Rebecca Lafreniere, deputy director, San Diego County Environmental Health Services Dr. Eric McDonald, medical director, San Diego County Epidemiology and Immunization Services

Our top story on Midday Edition, pesticide spraying NSX no Mount Hope got underway this morning. The spraying is to prevent the possibility of the spread of the Zika virus. And resident tested positive last week for a travel related Zika infection. Can see officials say the spraying is a precaution but there are those who are protesting the action. If you residents reportedly objected to the spraying in the county may return to those residences with a court order. I spoke with Rebecca Lawson, deputy director of environmental health for San Diego County and Doctor Eric McDonald, ethical director of San Diego County's epidemiology and immunization services. Doctor McDonnell, do we know where this resident picked up the Zika virus? We do. It's one of the Zika affected countries and we are not specifying just for patient privacy reasons. Is the patient recovered? Yes. The individual had mild symptoms. Those have resolved. That is usual with Zika. 80% of people have no symptoms and most of the remaining have very mild symptoms. Obviously there are concerns because of Zika can lead to microcephaly or Guillain-Barre or in very rare cases, hospitalization and death. Two actor McDonough, if a person is infected with Zika and they are bitten by a mosquito, how can that spread the virus? It has to be a specific mosquito called the invasive Aedes . That mosquito bites somebody. They could pick up the virus , usually 10 or 11 days later, the virus has reproduced in the mosquito and then that mosquito can bite others. It can cause them to be exposed to the virus. Also, the mosquito can lay eggs which can transmit the virus to the eggs and future generations of mosquitoes. Rebecca Lawson, should the county have tested the mosquitoes first before spring? The primary response is you want to prevent a local transmission. So if you have a person that is suspected or confirmed with this type of mosquito-borne illness and you have the detection of that invasive mosquito that is capable of vectoring it, time is of the essence. As Doctor McDonald mentioned, it takes 10 to 11 days for that virus to replicate in the mosquito. And become capable of transmitting to another person. So really it's a timing issue and we want to reduce the risk to elevated Public Health. Rebecca, what kind of pesticide is used in the Zika spring? We are using a Pyrenone 25 five health inspected insecticide is been improved by the EPA for application against adult mosquitoes. Doctor McDonnell, does this particular pesticide poses any dangers to the public? No. The risk is really, very, very minimal. It is countered by the fact that we are using an ultralow volume spray. They are, in fact, taking prescriptions in each of the specific areas where they are applying the low volume spray. Really, the amount of insecticide that is used and the precautions that are taken in the environment where it's applied really minimize risk to people into pets. What is precautions? For example, individuals whose properties are being sprayed want to keep their windows closed and fans off and shut off the air conditioners for about 30 minutes. This product actually breaks down relatively quickly by the ultraviolet rays of the sun. Within 20 minutes of the application, it is broken down. We do encourage people if they can to take their pets indoors and leave the area for about 30 minutes. If they have homegrown fruits or vegetables, wash those prior to preparing those for consumption. Any type of ornamental fish ponds, again, it's good to cover those so the product -- again, minimizes the potential exposure. This is spring is happening in the neighborhood in Mount Hope and, Rebecca, some people believe that county officials are quicker to spray in lower income neighborhoods. I wonder what your responses to that. No. This is in response to an elevated risk to public health. No matter where it stayed in the county. If we have a suspect or confirmed case of a mosquito borne illness such as a Zika, and we have the invasive species of mosquitoes, the Aedes aegypti in this case, then an application of a chemical control for mosquitoes is warranted. This is a question perhaps that you can't answer but I'm going to ask it anyway. Should we expect more preemptive springs like this in San Diego County in the near future? Really what we need is for the public to partner with us in eliminating and preventing mosquito breeding on their property. As we get to suspected or confirmed cases of mosquito-borne illness like a Zika or dengue or two begonia and we have the protection of the invasive mosquitoes, then the county will continue to use adult chemical control against adult mosquitoes. Again, to reduce the elevated risk to public health. Ended her been reports of the deaths as well as a result of Zika spring. Is that a concern here, Rebecca? We are very much aware of the bees. In fact we encourage local hobbyists of bees, the county of San Diego apartment of ag weights and measures maintains a list of apiary's and also this is something that local be hobbyists can register with. They are notified in the event that any type of an agricultural pesticide is applied within one mile. We utilize that list to proactively reach out to the beekeepers and let them know that we are spraying because of an elevated risk to public health. So they have the opportunity to take any necessary precautions. Doctor McDonnell, are we moving out of the season where the spread of mosquito-borne illnesses is going to end in San Diego? Well, actually, there are a number of Zika affected countries across the globe and I think the Zika threat for travelers is going to persist for quite some time. Again, local conditions for mosquitoes in San Diego will still be with us for a number of months. I think we're focusing on Zika but we need to remember that West Nile virus is also a threat. It has sickened a San Diegans already this year and that season also lasts through the late fall, early winter. I've been speaking with Doctor Eric McDonald, Doctor Sandy Eagle County epidemiology and immunization services and Rebecca Lawson, deputy director of the environmental health for San Diego County. Thank you both very much. Thank you.

Mount Hope Sprayed For Mosquitoes After Positive Zika Test
County vector control workers began spraying part of the neighborhood after an area resident tested positive for the Zika virus. But not everyone was happy about it.

San Diego County vector control workers began spraying part of the Mount Hope neighborhood Tuesday in an effort to kill mosquitoes after an area resident tested positive for the Zika virus.

County vector control crews sprayed the area bounded by F Street on the north, Market Street on the south, Raven Street on the east and Quail Street on the west with Pyrenone 25-5 in an effort to kill adult mosquitoes.


According to the county, Aedes mosquitoes that can transmit Zika and other diseases were found after an area resident contracted Zika while visiting a country where mosquito-borne illnesses are prevalent.

"Travel to Zika-affected countries is common, and actions to prevent Zika from spreading to local Aedes mosquitoes are vital to inhibit locally acquired human cases of this disease," county Public Health Officer Wilma Wooten said.

But not everyone was happy about the move.

Some residents put up signs telling the county not to spray on their property. Because of the potential health threat, officials said they can come back with a court order, if necessary.

Resident Brad Michels said he was concerned about the spray and its impact on his pets, organic garden and daughter. He told 10News that county officials didn't alert residents until Saturday evening.


"The offices were all closed for the holiday," Michels said. "A lot of people in the neighborhood are gone because of the holiday, and then they come back to find out that they're spraying and they don't know what to do or how to go about stopping it."

Syd Stevens trailed county vector control workers with a bull horn.

"There is no local control in our own neighborhoods," Stevens said.

According to county officials, the pesticide poses low risks to people and pets, but residents in the area who want to minimize their exposure can take precautionary steps, including:

• staying inside and bringing pets indoors if possible

• closing doors and windows

• turning off fans that bring outdoor air inside the home

• covering ornamental fish ponds to avoid direct exposure

• rinsing fruits and vegetables from gardens with water before cooking or eating

• wiping down or covering outdoor items such as toys

• covering barbecue grills

"Unfortunately, finding any (Aedes mosquitoes) indicates the need for action," said Eric McDonald, epidemiology medical director at the county health department.

Corrected: February 21, 2024 at 11:04 AM PST
Editor's note: This story has been updated to reflect the correct last name of the San Diego County Environmental Health Services deputy director. Rebecca Lafreniere was misidentified as Rebecca Lawson in the interview. We apologize for the error.