Preview Articles

What are mosquito-borne diseases?

• Diseases spread by infected mosquitoes—in the United States, most are caused by viruses.

• Examples of viruses spread by mosquitoes include West Nile virus, eastern equine encephalomyelitis (EEE), St Louis encephalitis (SLE), La Crosse encephalitis, western equine encephalomyelitis (WEE), dengue, chikungunya, and Zika virus.

• In children, most of these infections produce no signs or symptoms or only mild headache and fever. More severe illness (including central nervous system involvement) can occur, especially among adults.

• Malaria is a mosquito-borne disease caused by a parasite that occurs commonly in tropical regions. It is extremely rare in the United States, except among international travelers.

• Dengue and chikungunya are mosquito-borne viruses that have recently been introduced into the United States. Dengue has caused illness in certain southern states in recent years and is common in Hawaii, Puerto Rico, the Virgin Islands, and American Samoa, where children may travel. Chikungunya is another recent virus spread by mosquitoes that has come to the United States. Hundreds of cases are reported in the United States each year, nearly all from international travelers.

• Zika is a mosquito-borne disease that usually causes mild illness that lasts from several days to a week. Outbreaks of Zika have occurred in Africa, Southeast Asia, the Pacific Islands, and the Americas but have been spreading to new areas of the world. Zika infection can be transmitted from mosquito bites, sexual contact, and an infected pregnant individual to their fetus. Most cases in the United States occur from travelers returning from affected areas, but small numbers of locally acquired infection from mosquitoes in the United States began in 2016 in Florida and Texas. For the most recent information, visit the Centers for Disease Control and Prevention (CDC) Zika website at www.cdc.gov/zika . When Zika virus infects a pregnant individual, it can spread to their fetus and cause microcephaly and other brain defects. The CDC recommends pregnant individuals consider postponing travel to areas where Zika virus is spreading, use repellents and other measures to avoid mosquito bites if they do travel to these areas, and use condoms for sexual activity of any type while pregnant.

What are the signs or symptoms?

• Many people have few signs or symptoms.

• Fever

• Headache

• Body aches

• Nausea

• Vomiting

• Rash

• Convulsions

• Coma

• Paralysis (in West Nile disease, paralysis of the facial muscles [Bell palsy] has been noted).

• Joint pain and conjunctivitis (pinkeye or red eyes) for Zika.

What are the incubation and contagious periods?

• Incubation periods

  • – Chikungunya: 2 to 4 days

  • – Dengue fever: 4 to 8 days

  • – EEE: 4 to 10 days

  • – La Crosse encephalitis: 5 to 15 days

  • – SLE: 4 to 14 days

  • – WEE: 5 to 10 days

  • – West Nile virus: 2 to 14 days

  • – Zika: 3 to 14 days

• Contagious period: These infections are not contagious except Zika virus, which can be transmitted from person to person; the virus has been detected in blood, urine, saliva, and semen for weeks after initial infection.

How are they spread?

Through the bite of an infected mosquito. West Nile and Zika virus may also be spread by blood transfusion and organ donation. Zika virus can also be transmitted from a pregnant individual to their fetus and through sexual contact with an infected individual.

How do you control them?

• Avoid mosquito bites and get rid of standing water where mosquitoes lay their eggs.

• Do not wear products that have an odor. They attract mosquitoes.

• Protect the skin by wearing clothing that puts a barrier over the skin, like long sleeves, long pants, socks, shoes, and hats.

• Use insect repellents containing diethyltoluamide (DEET). Repellents make the user unattractive to mosquitoes. They do not kill the insects.

• Information about DEET is as follows:

  • – DEET may be applied according to instructions from the CDC ( www.cdc.gov/ticks/prevention/index.html ) and the US Environmental Protection Agency (EPA) ( www.epa.gov/insect-repellents/deet ).

  • – DEET is safe when used according to the instructions on the product label. Be careful not to get it into the eyes or mouth because it can irritate these tissues. DEET is available in different concentrations. The concentration determines the length of time DEET will provide protection. Products with less than 10% active ingredient may only offer protection for 1 to 2 hours. Newer formulations of DEET that offer sustained-release or controlled-release (microencapsulated) formulations, even with lower active-ingredient concentrations, may provide longer protection times, up to 12 hours. Concentrations of DEET higher than 50% do not offer much more protection time than those that contain 50% DEET. The CDC recommends using products containing 20% to 30% DEET on exposed skin to reduce biting by ticks that may spread disease.

  • – Products that combine DEET with sunscreen should not be used. Sunscreens need to be reapplied at least every 2 hours because they can be washed off by water play or sweating. Repeated application may increase the potential toxic effects of DEET.

  • – Apply DEET sparingly on exposed skin; do not use under clothing. If repellent is applied to clothing, wash or dry-clean treated clothing before wearing again.

  • – Do not use DEET on the hands of young children; avoid applying to areas around the eyes and mouth.

  • – Do not use DEET over cuts, wounds, or irritated skin. Wash treated skin with soap and water after returning indoors.

  • – Avoid spraying in enclosed areas; do not use DEET near food.

  • – According to the EPA, there is no age restriction for DEET use. For infants and young children, use of products with the lowest effective DEET concentrations (ie, between 20% and 30%) seems most prudent. For infants and young children, DEET should be applied sparingly—preferably applied to clothing when possible. If DEET is used on the skin of infants and young children, it should be applied as a very small amount to exposed skin and only to skin children cannot put into their mouths.

  • – Obtain written permission from the parent/guardian to use tick repellent and follow the instructions on the label. A pediatric health professional note is not required.

• Picaridin (also known as icaridin ) has been shown to be effective mosquito repellent, although less so than DEET. Picaridin will not damage certain fabrics and plastics that are stained by DEET. Picaridin products have a protection time of 2 to 12 hours, similar to DEET. Some plant-based products, such as oil of lemon, eucalyptus, and citronella, show some benefit, although they are not as effective as DEET.

• Many other products claim they prevent mosquito bites, but objective evaluation of them finds they are of little or no value. Among the products that have been found to be ineffective in objective tests are catnip oil, essential plant oils, garlic, vitamin B ₁ , wearing sound-producing devices, or wearing impregnated wristbands.

• Mosquito traps, bug zappers, ultrasonic repellents, and other devices to prevent mosquito bites are not very effective. Spatial repellent devices that release a repellent material into an area in the form of a vapor are becoming widely available. These products release volatile active ingredients, such as the pest repellents metofluthrin and allethrin, and are approved by the EPA for use outdoors. Although many of these products have documented repellent activity, their ability to provide protection from mosquito bites has not been evaluated thoroughly.

• If possible, stay inside during dusk and dawn, when mosquitoes are most active. When outside at these times, wear long sleeves and long pants.

• Check windows to make sure there are no holes in the screens to allow mosquitoes to get indoors.

• Empty or remove standing water from wading pools, buckets, pet dishes, flowerpots, areas where gutter drains leave standing water, and other sources that can attract mosquitoes.

• Some mosquitoes that spread certain viral diseases are active during the day (eg, Zika virus, which can damage a pregnant individual’s fetus). Where Zika is known to be spreading, pregnant individuals should use the measures described herein to prevent mosquito bites at any time of day.

What are the roles of the educator and the family?

• Follow public health recommendations about preventing mosquito bites.

• Share information about mosquito-borne diseases.

Exclude from educational setting?

No, unless

• The child is unable to participate and staff members determine they cannot care for the child without compromising their ability to care for the health and safety of the other children in the group.

• The child meets other exclusion criteria (see Conditions Requiring Temporary Exclusion in Chapter 4 of Managing Infectious Diseases in Child Care and Schools: A Quick Reference Guide, 7th Edition ).

Readmit to educational setting?

Yes, when all the following criteria are met:

When exclusion criteria are resolved, the child is able to participate, and staff members determine they can care for the child without compromising their ability to care for the health and safety of the other children in the group