Epidemics caused by mosquito-borne viruses are becoming more frequent, partly due to climate change. However, a recent survey indicates that most Americans are not overly concerned about contracting diseases like West Nile or dengue virus in the near future, and their understanding of protective measures is lacking. Dr. Anthony Fauci, former leader of the National Institute of Allergy and Infectious Diseases, was hospitalized last summer with West Nile virus, which he recounted in a New York Times article this week. His experience has heightened awareness about the risks associated with mosquito-borne diseases that include Zika, malaria, dengue, and West Nile virus. According to the Centers for Disease Control and Prevention (CDC), milder winters and warmer springs are allowing mosquitoes and ticks longer periods to reproduce, spread illness, and expand their range across the U.S.
This year, the CDC reported 880 cases of West Nile virus in the United States as of October 1, making it the most common insect-spread viral illness in the country. But West Nile isn’t the only concern; California officials recently issued warnings about an “unprecedented” rise in dengue fever cases. In August, a man died in New Hampshire due to Eastern equine encephalitis (EEE). CNN noted, “This summer has seen a surge in alerts regarding mosquito-borne diseases, including malaria, dengue, and EEE.”
Yet, according to a new health knowledge survey from the Annenberg Public Policy Center (APPC), just 15% of Americans are worried about their families contracting either dengue or West Nile virus in the next three months. The survey, which included over 1,700 U.S. adults and was conducted in late September, revealed gaps in public awareness regarding these diseases and prevention methods.
“Dr. Fauci’s situation serves as a reminder,” said Kathleen Hall Jamieson, director of the APPC and the survey, “that you don’t need to travel to far-off locations to encounter mosquitoes that can cause serious illnesses—they might be present right in your backyard.”
How Dengue Fever and West Nile Virus are Contracted
Infected mosquito (yes): The primary way to get dengue or West Nile virus is through the bite of an infected Aedes mosquito. Approximately 74% of those surveyed are aware that this vector is responsible for transmission of these viruses.
Sneezing and coughing (no): There is confusion about whether one can contract dengue or West Nile virus from someone who sneezes or coughs on them. The CDC states that this is not possible; however, only about one-third (34%) correctly believe that transmission via sneezing or coughing is unlikely. About 26% mistakenly think this is a valid mode of transmission, and 39% are unsure.
Understanding Symptoms of West Nile Virus
While most individuals know that mosquito bites can lead to dengue or West Nile virus infections, many are unaware of the specific symptoms associated with West Nile virus. When asked to identify symptoms, less than half chose those recognized by the CDC as indicators of West Nile virus.
The percentage of respondents who identified the following CDC-recognized symptoms of West Nile virus:
- 42% fever
- 37% muscle and joint pain
- 36% headache
- 29% nausea and vomiting
- 22% rash
Conversely, those who incorrectly selected symptoms not associated with West Nile virus included:
- 28% dizziness or lightheadedness
- 11% firm, round, painless sore
Beliefs About Contracting Dengue Fever and West Nile Virus
Scientists have been experimenting with genetically modified (GM) mosquitoes in various countries like Brazil, Panama, and India to control mosquito populations. These GM mosquitoes are designed to ensure that female offspring do not survive to adulthood, helping to reduce the spread of mosquito-borne diseases.
In the survey, only 16% of respondents believe that genetically modified mosquitoes have caused dengue fever outbreaks, while 36% correctly know this is not true, and 48% are unsure. More individuals (36%) think that genetically modified mosquitoes could effectively decrease the spread of dengue fever, while 16% disagree, and 48% remain uncertain.
According to the CDC, the Aedes mosquito that carries the dengue virus is not found in all U.S. states. Yet, 38% of respondents incorrectly believe that these mosquitoes are located in every state across the continental U.S., with only 22% correctly stating this is false and 40% unsure.
- Preventing dengue and West Nile virus: Nearly 80% (79%) correctly assert that the best defense against dengue and West Nile virus lies in avoiding mosquito bites and controlling nearby mosquitoes, while 17% are unsure, and 4% disagree.
- Antiviral treatment: Currently, there are no antiviral treatments available for dengue fever or West Nile virus. Only about a quarter (23%) are aware of this fact, while 15% believe there is a treatment, and the majority (62%) are unsure.
Taking Precautions Against Mosquito Bites
The CDC recommends actions to minimize the risk of mosquito bites. Approximately 59% of survey participants say they typically take precautions against mosquito bites at any time of year, which is a drop from about 67% who affirmed this in a summer 2016 APPC survey during the Zika outbreak. Today, about 37% claim they do not regularly take precautions.
Among those who reported routinely taking precautions, we asked about specific actions:
- The most common precaution is eliminating standing water (80%), closely followed by using insect repellent (72%). Both figures have remained steady since we last surveyed them in July 2016.
- 70% avoid activities or areas where they might encounter mosquitoes, an increase from 63% in July 2016.
- 64% say they regularly check or replace window screens, unchanged from July 2016.
- 57% wear long-sleeved shirts or other protective clothing while outdoors, a rise from 52% in July 2016.
- Only 12% use mosquito netting regularly, which is consistent with July 2016 figures.
How to Apply Insect Repellent and Sunscreen
Insect repellent is crucial for preventing mosquito bites, but it is also essential to use sunscreen when outside to protect against harmful UV rays. We asked participants how the CDC recommends combining the application of insect repellent and sunscreen.
In general, about 30% of respondents (29%) correctly know that the CDC suggests that It’s essential to apply sunscreen first and allow it to dry before using insect repellent. Only a small percentage (5%) believe that the CDC suggests applying insect repellent first, followed by sunscreen. Furthermore, 16% think the CDC indicates that the order of application doesn’t matter, as long as both products are used in mosquito-prone areas. Both of these beliefs go against the CDC’s guidance. Half of the respondents (50%) are unsure about the CDC’s recommendations on this matter.
Applying insect repellent only to exposed skin
The CDC strongly advises against applying insect repellent to skin that is covered by clothing. Only 13% of individuals are aware of this recommendation. Almost half believe that the CDC suggests applying insect repellent on the skin and then wearing clothes over it (19%), or that the order of applying repellent under clothing is unimportant but should be used in areas with mosquitoes (29%). Meanwhile, 39% are uncertain about the CDC’s advice on this topic.
Avoiding insect repellent for young infants
More than half of the participants (52%) correctly state that the CDC advises against using insect repellent on infants under 2 months old, recommending instead that they wear clothing that covers their arms and legs and that mosquito netting be placed over their cribs, strollers, and carriers. Nevertheless, 45% are unsure about the CDC’s stance on repellent use for infants. Additionally, 3% mistakenly believe that the CDC allows insect repellent for babies under 2 months, which is not correct.
Choosing an EPA-registered insect repellent
The CDC suggests looking for insect repellents that are registered with the EPA, a fact recognized by just over 20% (21%) of people. Nearly a third (29%) believe the CDC recommends using products containing more than 50% DEET, while 6% think the CDC advises looking for “natural” insect repellents. The largest group (43%) is unsure about CDC recommendations in this area.
DEET is the main active ingredient found in many insect repellents. The CDC notes that while higher concentrations of DEET might last longer, products with 50% DEET or more do not offer better protection than those with lower levels of DEET.
