Published on October 21, 2007
Mosquito Season and the Illnesses it Could Bring: Mosquito Season and the Illnesses it Could Bring Mosquito Bite Prevention La Crosse Encephalitis West Nile Virus Prepared by Mason County Health Department Let’s Talk About Mosquitoes: Let’s Talk About Mosquitoes Mosquitoe bites can cause illnesses such as LaCrosse Encephalitis and West Nile Virus. The key to the prevention of these two diseases is prevention of mosquitoes and bites by infected mosquitoes. How does a Mosquito Grow?: How does a Mosquito Grow? Mosquitoes lay eggs in areas that harbor water. These areas could occur naturally such as with low lying areas in the ground or could be man made such as with flower pots, old tires and gutters that don’t drain properly. Slide4: Photograph used with the permission of Dr. James Joy, Department of Biology, Marshall University. Slide6: Tree-holes and Oc.triseriatus larvae Prevention of Breeding Grounds for Mosquitoes: Prevention of Breeding Grounds for Mosquitoes Empty standing water in old tires, cemetery urns, buckets, plastic covers, toys or any other container where mosquitoes may breed. Empty and change the water in bird baths, fountains, wading pools, rain barrels, and potted plant trays at least once a week if not more often. Make sure you empty buckets and other containers that could contain water: Make sure you empty buckets and other containers that could contain water Prevention continued: Prevention continued Drain or fill temporary pools with dirt. Keep swimming pools treated and circulating. Keep rain gutters clean and in good repair. Use head nets, long sleeves, and long pants if you venture into areas with high mosquito populations. Make sure window and door screens are “bug tight.” Mosquitoes: Mosquitoes The female lays it’s eggs on the water. If the water is stagnant, it does not interrupt the hatching process and the larvae of the mosquito continues to grow. Slide11: Culex Mosquito laying eggs Egg raft Slide13: Culex–type Mosquito Larvae “ wigglers” Siphon (Aedes, Culex, Ochlerotatus and Psorophora) Slide14: Anopheles No siphon Slide15: Mosquito Pupae “tumblers” trumpets Slide16: Adult emergence Mosquito Bites: Mosquito Bites The mosquito is attracted by carbon dioxide that is emitted as we breathe as well as other scents. Slide18: Female Mosquito (Cx. quinquefasciatus) Blood Feeding on a finger Preventionof Mosquito Bites: Prevention of Mosquito Bites Wear long sleeves and long pants when working in the yard, particularly in areas that you know have a lot of mosquitoes. Many of the mosquitoes that carry the West Nile Virus are more visible around dusk and dawn. Avoid these times to be outside. Use of mosquito repellent. Use mosquito netting over infant carriers. Use of Mosquito Repellents: Use of Mosquito Repellents Mosquito Repellents Contain DEET: Mosquito Repellents Contain DEET Is DEET safe? How often should it be reapplied? How does it work? Why does CDC recommend using DEET? General considerations in using DEET. DEET and children. DEET and sunscreen. Is DEET Safe?: Is DEET Safe? CDC states that products containing DEET are very safe when used according to the directions. The regulation of DEET is determined by the US Environmental Protection Agency (EPA). Laboratory testing regarding both short-term and long-term health effects have been carried out. Over the long history of DEET use, very few confirmed incidents or reactions to DEET have occurred when the product is used properly. When and how often should I apply DEET?: When and how often should I apply DEET? Apply repellents when you are going to be outdoors and at risk for mosquito bites. Follow the directions on the product for reapplication. Sweating, perspiration, or getting wet may mean you need to re-apply more frequently. Repellents containing a higher concentration of DEET provide longer lasting protection. How does the repellent work?: How does the repellent work? Female mosquitoes bite people and animals because they need the protein in the blood to help develop their eggs. Mosquitoes are attracted to people by skin odors and carbon dioxide from breath. DEET repels the mosquito, making the person unattractive for feeding. Repellents are effective only at short distances from the treated area, you may still see the mosquito flying, but you won’t get bitten. Why does the CDC recommend using DEET?: Why does the CDC recommend using DEET? DEET is the most effective and best-studied insect repellent available. Studies using humans and mosquitoes report that among those tested, products containing DEET offer long-lasting protection after a single application. General Consideration in using DEET: General Consideration in using DEET Always follow the recommendations appearing on the product label. Use enough repellent to cover exposed skin or clothing. Don’t apply repellent to skin that is under clothing. Heavy application is not necessary. Do not apply repellents to cuts, wounds, or irritated skin. After returning indoors, wash treated skin with soap and water. More general considerations: More general considerations Do not spray aerosol or pump products in enclosed areas. Do not apply aerosol or pump products directly to your face. Spray on your hands and then rub them carefully over the face, avoiding eyes and mouths. (Not to be used on children’s faces.) DEET and Children: DEET and Children No definitive studies exist in the literature as to what concentration of DEET is safe for children. No serious illnesses have been linked to the use of DEET when used according to the product recommendations. DEET and Children: DEET and Children The American Academy of Pediatrics has recently updated their recommendation for use of DEET products on children. “Insect repellents containing DEET with a concentration of 10% appear to be as safe as products with a concentration of 30% when used according to the directions on the product labels.” DEET and Children: DEET and Children The American Academy of Pediatrics and other experts suggest using repellent with low concentrations of DEET on infants over 2 months old. Other guidelines suggest using repellents containing DEET after children are 2 years of age. Check with your pediatrician. Application of DEET with Children: Application of DEET with Children Always follow the product recommendations. Apply to your hands and then rub them on your child. Do not spray directly on the child. Avoid children’s eyes and mouth and use sparingly around their ears. Do not apply to children’s hands. They may put their hands in their mouth. Keep out of reach of children. Do not allow children to self apply. Risks of Using DEET: Risks of Using DEET Use of these products may cause skin reactions in rare cases. If you suspect a reaction to this product, discontinue use, wash the treated skin, and call your local poison control center. 1-800-222-1222 DEET with Pregnant or Nursing Women: DEET with Pregnant or Nursing Women There are no reported adverse events following use of repellents containing DEET in pregnant and breastfeeding women. What about DEET and Sunscreens?: What about DEET and Sunscreens? You can use both products at the same time. Follow the directions for each product. Apply the sunscreen first, followed by the repellent containing DEET. CDC does not recommend using a combination product because DEET does not need to be reapplied as often as sunscreen. Non-DEET Repellents: Non-DEET Repellents Some non-DEET repellent products which are intended to be applied directly to the skin may also provide limited protection from mosquito bites. However, because studies suggest that other products do not offer the same level of protection, or that protection does not last as long as the protection provided by products containing DEET, you should use DEET if possible. Illnesses caused by Mosquito Bites: Illnesses caused by Mosquito Bites La Crosse Encephalitis West Nile Virus Comparison to La Crosse Encephalitis and West Nile Virus: Comparison to La Crosse Encephalitis and West Nile Virus La Crosse Spread only by the treehole mosquito. Children under age 16 are most at risk but can occur at any age West Nile Virus Spread by infected mosquitoes. People over age 50 are most at risk. Anyone who does protect against mosquito bites. What are the symptoms?: What are the symptoms? Most people who get La Crosse Encephalitis or West Nile Virus never have symptoms. Most Common Symptoms: Most Common Symptoms La Crosse Headache Fever Nausea Vomiting Drowsiness Confusion West Nile Virus Headache Fever Body aches More Serious Symptoms: More Serious Symptoms La Crosse Seizures May go into a coma Rarely fatal but may have headaches, seizures or other problems after they get well. West Nile Virus Fever Fatigue Confusion Headache Weakness Nausea-Vomiting Stiff neck Abdominal pain How it is NOT Spread: How it is NOT Spread Both La Crosse Encephalitis and West Nile Virus are spread by mosquito bites. Neither one is spread from person to person Summer Time is Fun Time!: Summer Time is Fun Time! The Mason County Health Department wishes you a safe and fun summer time!