Stop Those Suckers
NMSU Extension expert provides tips for
mosquito-proofing your yard
By Justin Bannister
Unfortunately, the dry New Mexico desert doesn’t protect the state from mosquitoes. These bloodsuckers emerge each year and, according to Jeff Anderson, the Agronomy and Horticulture Agent for New Mexico State University’s Dona Ana County Cooperative Extension Service, the state’s mosquitoes are especially active in July and August, once the monsoon season rains kick in.
Anderson warns the mosquitoes that carry the dangerous Zika virus, known as Aedes aegypti mosquitoes, are found in Dona Ana County. And, unlike other mosquitoes, these are especially aggressive during the day, and only land on humans for a short time, making them harder to spot and swat.
Anderson offers the following tips for mosquito-proofing your yard:
Find dry land.
Get rid of any standing water around your home. Old tires, plastic buckets and toys left outside can collect rainwater where mosquitoes lay eggs. Taking care of your property won’t just help you; it will help the whole neighborhood.
Be water smart.
Too much water on your lawn can make it a breeding ground for mosquitoes. Don’t overwater. It’s also a good idea to water in the morning, instead of in the evening, so the soil has an opportunity to dry during the day.
Spray the bugs away.
Use mosquito repellent that contains DEET when you’re outdoors. For those allergic to DEET, stores often have natural repellents as well.
Use power plants.
Some forms of eucalyptus, as well as lavender, can repel mosquitoes simply by being planted in an area. Other plants, such as basil and catnip, produce oils in their leaves, which can be crushed and used in sprays to repel mosquitoes.
Get an oil change.
Essential oils, including citrus, lemon eucalyptus, cedar, garlic and citronella, are useful in keeping mosquitoes at bay and can be purchased locally or online.
A number of granular mosquito prevention products for lawns and floating products for use in water features contain natural bacteria called Bacillus thuringiensis, which is toxic to mosquitoes, but won’t hurt pets, humans or other animals.
Dress for success.
Mosquitoes are attracted to heat, and dark-colored clothing tends to retain heat. During mosquito season, make sure to wear clothes that are light-colored, loose-fitting and long-sleeved.
Set some traps.
Studies have found that commercial carbon dioxide mosquito traps can kill thousands of mosquitoes a night. Bug zappers, on the other hand, aren’t as effective. Zappers kill bugs indiscriminately, and only about one percent of the zapped bugs turn out to be mosquitoes. Stick with the CO2 traps.
Bring in the big guns.
A number of chemical products specifically designed for mosquito control are available at local stores. Make sure to check for these products early, and stock up. They’ll sometimes run out before the end of mosquito season.
What’s the best mosquito repellent device on the market today?
NMSU researchers are testing top products to find out
By Dana Beasley
A s Congress haggles over how many millions or billions of dollars to spend to help stop the spread of the Zika virus in the U.S. before summer, researchers at New Mexico State University are already testing wearable mosquito repellent devices to determine which ones can best help us protect ourselves against these insects.
“The goal is to find out what works and what doesn’t,” said Immo Hansen, an NMSU associate professor of biology involved in the investigation. “There are so many products on the market that simply don’t work, so I think it’s really important to test them in a scientific way.”
“Some people just smell better to mosquitoes than others, and there’s really nothing you can do about that except wear repellents.”
This month, a group from Hansen’s Molecular Vector Physiology Lab, in the College of Arts and Sciences, began a series of tests to determine the effectiveness of a dozen commercially available wearable repellents, including clip-ons and wristbands. Though the study is ongoing, preliminary data revealed that citronella-based bracelets and wristbands have little effect on mosquitoes, whereas OFF Clip-On devices not only repel mosquitoes, they also kill them.
“Some people are really resistant to putting repellents on their skin, so they would rather choose a wearable device,” said Stacy Rodriguez, manager of NMSU’s Molecular Vector Physiology Lab and lead researcher on this project. “Right now, we are just trying to see if the wearable devices are as effective as the spray-on devices.”
The group plans to publish the results of this research by mid-summer.
This analysis is a follow-up to a study the group conducted last fall on 10 commercially available spray-on repellents. During this experiment, Rodriguez and her colleagues recognized the most reliable sprays as DEET products and lemon eucalyptus-based insect repellents.
For the current study, the group is testing the wearable devices using a 70-foot wind tunnel located in an NMSU research facility. After taking baseline readings, the researchers put on the repellent devices and position themselves upwind of a series of test cages. Depending on the product’s repellency, the caged mosquitoes either fly away from the test subjects or toward them.The wearable devices are being tested against the same two species of mosquito used in the spray repellent study: the Asian tiger mosquito (Aedes albopictus) and the yellow fever mosquito (Aedes aegypti), both of which carry the Zika virus.
“These two mosquitoes have very different levels of attraction to even one certain individual,” Rodriguez said. “Since attraction varies, repellency is also going to vary, so it’s important to test multiple species when you’re looking at repellents and their efficacy.”
Thanks to body chemistry, mosquitoes are also more inclined to bite someone who “smells” good to them.
“Everybody has a different bacterial flora on his or her skin,” Hansen said. “The bacteria break down components of sweat and produce a different set of olfactory clues for the mosquitoes. Some people just smell better to mosquitoes than others, and there’s really nothing you can do about that except wear repellents. There’s nothing you can do to change the bacterial flora on your skin.”
Consequently, these chemical differences can impact which repellents work best for you.
“Something that might work for one person because of his or her body chemistry, might not work for somebody else because he or she has different chemistry,” Rodriguez said.
While the Asian tiger mosquito hasn’t established significant populations in New Mexico, Aedes aegypti – one of the primary vectors of dengue, Zika virus and yellow fever – can be found in your backyard in Las Cruces.
“Be aware; prepare,” Hansen said. “Get yourself a good repellent, wear long sleeves, long pants. Try to avoid getting bit.”
The mosquito that carries the Zika virus can breed in as little as one centimeter of standing water, Hansen explained. For those with ponds, his recommendation was to get Gambusia, or mosquito fish, from the Doña Ana County Vector Control to keep backyard mosquito populations at bay.
Who is at risk of Zika virus?
Ever wonder why male mosquitoes don’t bite?
“They don’t have to make eggs,” explains researcher Immo Hansen. “But, the females need nutrient proteins, so they take up our blood.”
It’s through this process that vector, or disease-causing, mosquitoes transmit malaria, dengue fever, chikungunya, yellow fever viruses and other illnesses.
Next fall, Hansen and Rodriguez plan to investigate mosquito attractants for use in baits. Surprisingly, even though humans attract mosquitoes all the time, Rodriguez explained that creating a chemical to attract mosquitoes is actually harder than repelling them.
“We have such complex odors that it’s actually hard to emulate that in cream or a bait trap,” she said. “It’s actually much more complex than creating something that disguises your human smell.”
Coming soon to a wrist near you
New device being tested at NMSU may be the most effective repellent wearable yet
Hansen collaborated with NMSU’s technology incubator, Arrowhead Center, and the New Mexico Small Business Assistance program to test two band prototypes – one containing citronella and DEET, and the other containing oil of lemon eucalyptus and DEET.
Hansen said both prototypes were highly effective at reducing mosquito attraction.
The efficacy of both prototypes of the BugBling™ band was compared to two commercially available products – Invisiband and OFF ClipOn. The result: the effect of both BugBling™ bands were stronger than the two other products.
The company is continuing to develop the product, and is now in the process of registering the BugBling™ band with the Environmental Protection Agency.
Test your Zika knowledge
How much do you know about the threat of Zika virus and what you can do to protect yourself this summer? Take our quiz to find out!
Looking for the best spray-on repellent to protect yourself?
You might be surprised by what these researchers discovered
By Dana Beasley
If you want to keep away blood-sucking insects, DEET products are your best bet according to a recent study from New Mexico State University. Researchers also discovered a certain perfume performed better at protecting against mosquitoes than some commercial insect repellents.
“Not all repellents are created equal – unfortunately they’re advertised as such,” said Stacy Rodriguez, research assistant in NMSU’s Molecular Vector Physiology Lab. “It’s important to let consumers know what is actually effective.”
“Insect repellents can be highly efficient, but you need to find out which work.”
Recently, Rodriguez and other researchers in NMSU’s College of Arts and Sciences tested the effectiveness of 10 commercially available products intended to repel mosquitoes. Their findings were published recently in the “Journal of Insect Science.”
The products were tested against two common mosquito species: the yellow fever mosquito and the Asian tiger mosquito, both known to transmit dengue fever, chikungunya, yellow fever and other diseases.
“People need to protect themselves, especially if they travel to the tropics,” said Immo Hansen, an NMSU associate professor of biology involved in the study. “Insect repellents can be highly efficient, but you need to find out which work.”
Of the repellents tested, three of the sprays contained DEET as the active ingredient (Repel 100 Insect Repellent, OFF Deep Woods Insect Repellent VIII and Cutter Skinsations Insect Repellent), while four were DEET-free (Cutter Natural Insect Repellent, EcoSmart Organic Insect Repellent, Cutter Lemon Eucalyptus Insect Repellent and Avon Skin So Soft Bug Guard).
What’s the best protection from Zika?
The team also tested two fragrances (Avon Skin So Soft Bath Oil and Victoria’s Secret Bombshell perfume), and a vitamin B1-based Mosquito Skin Patch.
For the experiment, a volunteer’s bare hand served as the attractant. The researchers used a fan to push the volunteer’s scent through a Y-shaped tube toward a holding chamber containing roughly 20 mosquitoes. Upon release, the mosquitoes flew toward the hand if they were attracted to the scent; if repelled, the mosquitoes either flew to the opposite tube or did not move.
The non-DEET repellents had little to no effect on the yellow fever mosquito, with one exception: Cutter Lemon Eucalyptus Insect Repellent was found to have similar efficacy as the DEET repellents.
Surprisingly, the bath oil and perfume repelled this species for roughly two hours.
“There was some previous literature that said fruity, floral scents attracted mosquitoes, and to not wear those,” Rodriquez said. “It was interesting to see that the mosquitoes weren’t actually attracted to the person that was wearing the Victoria’s Secret perfume – they were repelled by it.”
The fragrance may provide a temporary masking effect, the researchers explained. They also clarified that there were high concentrations of perfume applied to the volunteer’s hand, and that lower concentrations may produce different results.
“Not all repellents are created equal – unfortunately they’re advertised as such. It’s important to let consumers know what is actually effective.”
The study found that Asian tiger mosquitoes were also repelled by the perfume. For this species, however, the DEET-free repellents produced mixed reactions, with the Avon Skin So Soft Bug Guard significantly reducing attraction for 120 minutes and the bath oil having no effect.
The skin patch, which claims to repel mosquitoes for up to 36 hours, did not repel either species.
To further this research, Rodriquez and Hansen are in the process of testing mosquito repellent bracelets and clip-on repellent devices, and intend to publish their results in time for next mosquito season.
The tests concluded that DEET products strongly repel both species of mosquito. The other products produced varied results.
Is New Mexico at risk of Zika virus?
NMSU researchers are scouring the state to find
where Zika-carrying mosquitoes are hiding
By Minerva Baumann
While the rest of the world is keeping its distance from the mosquito that carries the Zika virus, two New Mexico State University professors are seeking out this mosquito, which carries not only Zika but also a host of other diseases as well.
“Until people appreciated that it could cause birth defects, no one was interested in Zika. It causes very mild disease in adults. Fever, a little rash, that’s about it.”
Thanks to a $90,000 grant through the New Mexico Department of Health, NMSU biology professor Kathryn Hanley and NMSU geography professor Michaela Buenemann, both in the College of Arts and Sciences, and their graduate students will begin a project to trap mosquitos in different locations around New Mexico and generate a species distribution model that health officials can use to identify where the disease-carrying insects are most likely to be.
We know these mosquitoes occur in New Mexico,” said Buenemann. “We know these mosquitoes have been detected, but we don’t know their geographic distribution. We will collect samples at selected sites across the state and collect information about temperature, precipitation, land cover and other explanatory variables. We will then link these data in spatial models to map the distribution of mosquito vectors across the state.”
Hanley has been studying the Zika virus for 10 years. She and Buenemann previously mapped mosquitoes carrying the virus in Senegal, West Africa.
“Until people appreciated that it could cause birth defects, no one was interested in Zika,” said Hanley. “The reason no one paid much attention to Zika virus besides us is that it causes very mild disease in adults. Fever, a little rash, that’s about it.
“It’s only in 2015 that people noticed the association between Zika virus, pregnant women and microcephaly in the babies born to those women. What we found in 2015 is that not only is the virus transmitted by mosquitoes, but also it is sexually transmitted.” Hanley explained those who should worry most about Zika are women who might get pregnant or men carrying the virus who have sex with pregnant women.
How can I protect myself and my family from Zika virus?
“We don’t know the distribution of that vector in New Mexico. That’s critically important. If we want to assess our risk, if we want to know ‘Am I at risk of Zika infection from a mosquito bite?’ we need to know where that mosquito is.”
Stephanie Mundis, an NMSU graduate student with a double major in geography and biology, will spend the summer trapping mosquitoes in specific locations around the state as far north as southern Bernalillo County. Creating a map of mosquitoes that carry the Zika virus in New Mexico will be her thesis project. She expects to have mosquito collection data in the fall and to complete modeling next spring.
“We’re going to be basing our sampling on land cover, so we’re going to be sampling urban areas, agricultural, forest, barren, rangeland and wetlands,” Mundis said. “We’re trying to get a good sample for each of those land cover types so we know we’ve covered the types in the area.
“My thesis is based on modeling the potential distribution of these species throughout New Mexico,” said Mundis, while unfolding one of three types of traps she and another graduate student, Clara Hansen, will use to capture mosquitos in the wild.
The white fabric cylinder contains a lactic acid lure that attracts mosquitoes by mimicking the scent of human skin. The mosquitoes follow the scent into a cone in the cylinder and a fan sucks them into a net where they are captured.
“Here in New Mexico, the answer is yes: We have the vector for Zika virus. Zika will come to our area.”
How can I make my community safer?
“Once we catch them, we will be freezing them or putting them in coolers, keeping them as cool as possible. We will be using morphological keys to identify them. Just by looking at certain traits and patterns on their thorax, we can easily identify these mosquitoes.”
The Aedes aegypti mosquito, which carries the Zika virus, has noticeable white markings in the shape of a Greek lyre on its thorax and white banding on its legs.
Once the mosquitoes are captured and identified, layers of geographic data will be used to create a computer model to provide information for health officials and the general public.
“The problem with mosquitoes of course is that they are really, really tiny. We cannot see them from aerial or satellite imagery,” said Buenemann. “There is no quick fix to figure out where they actually occur. We’ll be tracking how the abundance of mosquitoes changes across space and through time, so we will have spatially and temporally somewhat explicit information that can be used to inform the public about when they are most likely be bitten by a potentially infected mosquito and where.”
Hanley hears two questions from most people about the Zika virus: Is Zika coming to my area, and what can I do to minimize my risk?
“Here in New Mexico, the answer is yes. We have the vector for Zika virus. Zika will come to our area,” Hanley said. “As for the risk, it depends on whether you are a reproductive age adult and interested in getting pregnant or you might have sex with someone who is pregnant or may get pregnant. If you’re outside that range, you don’t have to worry much.”
After mapping New Mexico for the mosquitoes that carry the Zika virus, Hanley and Buenemann will begin another project to map Zika virus transmission in Borneo to find out which animal species are transmitting the virus.
“We know that the virus occurs in monkeys in Africa and Asia,” Hanley said. “We’re worried it is going to get into monkeys in the Americas, because if it does that, we’ll never be able to eradicate Zika virus from the Americas.”
Why did Zika virus spill over to humans?
Fulbright Fellow Katie Young is in Borneo studying what drives mosquito-borne viruses to jump hosts
By Kristie Garcia
At times she may be found at the Hanley Lab on the New Mexico State University campus, but Katie Young is currently in Borneo studying the ecology of mosquito vectors, an extraordinary research project in an extraordinary location.
Young, who is pursuing a doctorate in biology at NMSU, received the prestigious United States Fulbright Student Scholar Award last year. As a Fulbright Fellow, she receives funding to support her travel and research in the southeast Asian island, where she is working with NMSU and The Institute of Health and Community Medicines at the Universiti Malaysia Sarawak.
“My research focuses on sylvatic arbovirus ecology, specifically mosquito-transmitted viruses such as dengue and Zika, in Malaysian Borneo,” she said. Arboviruses are viruses transmitted by arthropods, such as mosquitoes. “These two viruses emerged, likely due to spillover, into the human population from ancestral transmission cycles in non-human primates.
“These sylvatic (wild animal) viruses still circulate today and occasionally spill over into humans and often cause severe disease. My research aims to better understand the ecological drivers of spillover or host-jumps of mosquito-borne viruses.”
Young is collecting Aedes mosquito eggs in oil palm plantations and forests, where she is investigating how land cover may influence egg-laying cues for mosquito vectors and how mosquito blood source hosts are impacted by land cover. She also collects eggs from the boundary between these two land cover types.
The Fulbright Program is the flagship international educational exchange program sponsored by the U.S. government and is designed to increase mutual understanding between the people of other countries.
Mentors shape the next generation of groundbreaking researchers
In Dr. Hanley’s lab, Katie Young has developed expertise in a variety of methodologies ranging from virus culture to molecular taxonomy, which allows her to identify distinct mosquito species.
“Dr. Hanley put a lot of faith in me and allowed me to collect my master’s thesis data in Borneo,” Young said. “That experience truly prepared me for this long-term project I am conducting in Borneo now. She also pushed me to expand my abilities, not just in ecological research, but also microbiology and molecular biology.”
Young said working in The Hanley Lab at NMSU has helped her develop into a well-rounded scientist with a broad background.
“Without her advising and without the experience I’ve gained from working with her and the other Hanley Lab students, I don’t think I would be able to undertake such a large project,” she said.
After earning a bachelor’s degree in biology from Longwood University in 2008, Young earned a master’s degree in biology from NMSU in 2015.
“I collect blood-fed mosquitoes, mosquitoes which have recently taken blood from a host, and analyze the blood for the species from which it was taken,” Young said. “We collect these mosquitoes at varying distances from oil palm plantations, the main monoculture in Sarawak, Malaysia, to test for differences in diversity the farther you travel away from a plantation and into a forest.”
Forested areas converted to agriculture may affect the diversity of host species available to Aedes mosquitoes and may potentially be a driver of spillover if the remaining animals are potential hosts.
“Many mosquitoes take blood from multiple animal hosts; however, some species are very host-specific,” she said. “Because not all animals are capable of being infected with and transmitting certain arboviruses, diversity is a potential safety against viral spillover.”
Young has been able to build on her coursework in virology and emerging infectious diseases to study the viral infection of mosquitoes under the mentorship of Kathryn A. Hanley, associate professor of biology at NMSU.
Hanley, who holds a doctorate in biology and post-doctoral training in molecular virology, emphasized the importance of Young’s academic research.
“Katie has been doing ground-breaking research on the identity and distribution of the mosquito vectors of Zika virus and dengue virus in Borneo,” Hanley said. “We know that the Zika virus strain that hit the Americas came from Asia, but we know almost nothing about the behavior of the virus in Asia. Thus Katie’s research is very important for public health both abroad and here in New Mexico, where the mosquito vectors of Zika and dengue virus also occur.”
The Fulbright Program is the flagship international educational exchange program sponsored by the U.S. government and is designed to increase mutual understanding between the people of the United States and the people of other countries.
What do NMSU skeeters snack on? SkitoSnack!
With support from the Bill and Melinda Gates Foundation, Dr. Hansen and his team are developing an alternative to the animal blood needed by researchers to feed and breed large quantities of mosquitoes in the lab so they can be introduced into the wild and impact the mosquito population.
SkitoSnack consists of serum albumin and another protein that together support egg development in female Aedes aegypti mosquitoes.