A little more than 100 species of mosquitoes are known transmitters of diseases that are of concern to human health. But how? When a female mosquito has mated and is ready to lay eggs, she needs protein to help those eggs develop. To do this, the female seeks out blood for her source of protein. 

When taking a blood meal, they use specialized mouthparts called a proboscis. One of the inner parts of the proboscis is in charge of ejecting saliva. The saliva contains proteins to help mask pain, and has anticoagulating properties which keep the blood moving freely.

But if their blood source has specific diseases, they can accidentally ingest it from the blood: or if the mosquito is actively carrying disease they can pass it on through their saliva. This process is called the disease transmission cycle.

Not every mosquito transmits disease, and not every kind of mosquito can pass on the same ones. This is why identification of local mosquitoes is an important step in protecting public health. 

Not every country has mosquito control. When traveling outside of the USA to countries where mosquito-borne diseases are prevalent, please take the necessary precautions to protect yourself from mosquito bites. We may not have specific diseases in Sarasota County, but we do have the species of mosquitoes to carry them.

Several cases of mosquito-borne diseases are reported each year in Florida, imported from regions such as the Caribbean, Central & South America and Asia. Frequent international travel makes it possible to have diseases re-introduced locally.

Please remember to follow protective guidelines when traveling overseas, not just to protect yourself, but your family and community on your return home.

Dogs and Cats

Dogs and cats can get an infection from mosquitoes called heartworm. If preventative medicine is not taken, a thin parasitic roundworm can develop in the arteries of the heart causing blockage.

 Horses 

There are several mosquito-transmitted diseases that are potentially fatal for horses. Veterinarians can provide the best advice for horse caretakers and vaccines are available for some of these viruses. Horses are susceptible to: 

• Eastern Equine Encephalitis
• Western Equine Encephalitis
• St. Louis Encephalitis
• Venezuelan Encephalitis

Please note that humans can also contract the viruses listed above. Please visit The Florida Department of Health for information on animal contact and human health.

Sarasota County monitors adult mosquito populations year-round. Mosquito peak season occurs between May through October, when there is generally more rain and warmer temperatures. During this peak season we do the following each day to monitor the population of mosquitoes:

• Carbon dioxide baited traps in the field are set over night to attract and collect adult mosquitoes. Collection bags of adults from the trap are gathered early each morning and taken to the laboratory.
• The collection bags are placed in the freezer, so the mosquitoes keep intact and are euthanized. Later that morning the mosquito population is identified, counted, and recorded by our biologist using a microscope.
• The number of mosquitoes and the types of species determines what action is to be taken later that day. A daily "Mission Planning" meeting takes place which includes our Manager, Operations Supervisor, Biologist. The team gathers the scientific data to reach a consensus of whether a treatment is necessary and if so, where it should take place.
• Scheduled treatments are shared on the Homepage of this website, Sarasota County's Facebook and Twitter feed and on the Everbridge "ALERT Sarasota" notification system.

You may sign-up for our notifications here: ALERT Sarasota

In addition to monitoring adult mosquito populations, Mosquito Management also looks for the presence of viruses such as West Nile, Saint Louis encephalitis, Dengue, and others. This is completed in a technical manner:

• Specialized traps are set to collect adult, flying mosquitoes. The traps target different species of mosquito known to transmit diseases, breeding site preferences and particular geographic areas. 
• Collected mosquitoes are tested for the presence of virus on-site in our molecular laboratory.
• If a mosquito is found to be positive for a virus, Mosquito Management has an immediate response plan. More traps are set in the area and potential breeding sites are investigated.

To view the Florida Department of Health's weekly reports on mosquito-borne disease (and other arbovirus) surveillance, please visit the  Weekly Arbovirus Reports.

Mosquito Management Services monitors the potential risk of West Nile Virus with The Florida Department of Health by using sentinel chickens. Our chickens are placed throughout Sarasota County in coops and their blood is sampled weekly. Sentinel chickens do not contract the virus but instead produce an antibody response which we can detect in their blood. We send the chicken blood samples to the Department of Health and they look for antibodies through a blood assay. 

If antibodies are detected, the Department of Health infers that the chicken was bitten by an infected mosquito.  In other words, a positive disease response from a chicken sounds the alarm to let us know that virus is in the area. This is expected at low levels because birds are part of the nature cycle of certain types of disease transmission. At low levels, we will increase mosquito monitoring and disease surveillance in that general area to take a closer look at the situation. If we detect multiple chickens contracting a disease in a two-week span, that indicates a higher-than-normal risk of those diseases to humans. We would respond by increased treatments to that area, mosquito habitat source reduction if possible, and additional larviciding of water where immature mosquitoes are.

The threat of mosquito-borne illness prompts action when it is suspected or confirmed. 

• Because Mosquito Management conducts in-house testing for some mosquito-borne illnesses, action can be taken swiftly when it is detected in the local mosquito population.
  • This includes increased larval prevention, adulticide treatments, and public outreach. In areas where infected mosquitoes are found, adult mosquito population monitoring increases, and disease testing continues in-house and with support from the Florida Department of Health. 

• In cases where a human case is reported, those same efforts continue. The Florida Department of Health works with the patient to gather data regarding any recent travel, which could indicate the virus was contracted elsewhere.
  • Even if the person declares that they travelled during a time that aligns with the timeline of the virus' onset, Mosquito Management continues to monitor the local mosquito population. 
  • Not every mosquito is capable of transmitting every disease, so it's important to look for the species that are of concern if they were to bite the infected person.