The “mosquito growth crisis” in Las Vegas is a “ticking time bomb”

Las Vegas – Once believed to be inhospitable for mosquitoes, this city proves the opposite is true.

While these pests typically thrive in tropical, humid environments, their population has surged in the Las Vegas Valley in recent years due to various factors.

Urban development, climate change, insecticide resistance, and genetic adaptation have all created a more conducive environment for these insects in southern Nevada.

Las Vegas isn’t alone in its struggle against these pests; warm temperatures and shifting weather patterns are extending the habitats where mosquitoes can breed across the southwestern United States and beyond.

Besides being a nuisance, mosquitoes also pose a significant risk of mosquito-borne diseases like dengue and West Nile virus to Las Vegas and Clark County.

This situation has taken many by surprise.

“It’s not incorrect to say that mosquitoes shouldn’t thrive in desert conditions, but it’s evident that certain species present in Clark County have adapted to the local environment.”

“Time Bomb”

Among the species found in Clark County are the Culex mosquito, known to carry West Nile virus, and the Aedes aegypti mosquito, a primary transmitter of dengue. Researchers at UNLV have also identified resistance to insecticides in local mosquito populations.

According to Messenger, “It’s a time bomb that’s been ticking for a while.”

She is particularly concerned about Las Vegas’s vulnerability to mosquito-borne diseases. Dengue fever cases are on the rise in North and South America, with more than 13 million cases reported across the continent in 2024, as noted by the CDC.

“Las Vegas receives over 48 million visitors from around the world every year,” Messenger remarked. “Local transmission can start with just a single mosquito bite.”

Last year, 26 cases of West Nile virus were reported in the city. According to the Southern Nevada Health District, 2019 had the largest outbreak, but a record number of mosquitoes tested positive for the virus in and around Las Vegas in 2024.

While some mosquitoes have tested positive for the virus this year, the public health department has not identified any human cases so far. Messenger indicated that specific factors from previous years complicate their understanding of the situation.

“We see many overlapping factors, but it’s challenging to isolate them,” she said. “There are these bumper years and then none at all, making predictions difficult.”

The Southern Nevada Health District has been monitoring mosquitoes since 2004, keeping detailed records that show the types of mosquitoes present in the Las Vegas Valley and their associated diseases.

One striking trend has been the rapid increase in Aedes aegypti mosquitoes, first spotted in Las Vegas in 2017, according to Vivek Raman, an environmental health supervisor for the Southern Nevada Health District.

“Relentless Biting” Spreads

“In 2017, we found this mosquito in just a few zip codes,” Raman noted. “A few years later, it expanded to six, then twelve, and now it has appeared in 48 different zip codes throughout the valley.”

These insects not only spread dengue fever but are also a significant nuisance.

“The Aedes aegypti is an extremely aggressive daytime mosquito,” Raman explained. “Their bites are relentless.”

Unlike Culex mosquitoes, they prefer to breed near larger water sources, such as neglected swimming pools, dark corners, and detention ponds.

“One of the reasons for their rapid spread is their ability to lay eggs in small containers, like children’s toys, tires, or wheelbarrows,” Raman added. “Just a few inches of water are enough.”

Urban development in Las Vegas has also redirected mosquito populations. According to Messenger, golf courses, artificial lakes, and other irrigation methods have transformed the Nevada desert into an inviting habitat for mosquitoes.

Climate change is another contributing factor and is under active investigation by Messenger and other scientists. Higher temperatures are broadening the areas where mosquitoes can thrive. Warm air can hold more moisture, leading to increased humidity and rainfall—all ideal for mosquito breeding.

While it’s not entirely clear how local environmental aspects interact with shifting climate trends to impact mosquito populations, the potential consequences are significant.

“Las Vegas serves as a case study for how climate change may manifest in other regions globally,” Messenger stated. “We’re witnessing record temperatures and increasingly erratic precipitation patterns. This is predictive of what much of the world may look like in the next 15-25 years.”

The implications for urban mosquito populations remain uncertain, but current trends show no signs of abating.

Health districts in southern Nevada are engaging in public outreach to help residents identify and manage mosquito breeding sites around their homes, along with strategies to prevent bites. To effectively address mosquito populations and associated public health risks, comprehensive efforts from local governments are essential, according to Messenger. Right now, this level of coordination is lacking in Las Vegas.

“We have private pest control companies, and some work is being done around wetlands, but what we lack is a centralized and coordinated reduction effort across multiple jurisdictions,” Messenger explained.

That absence of coordinated action has contributed to mosquito populations becoming increasingly resistant to insecticides. Ongoing monitoring is necessary to determine which chemicals are safe to use around humans and to evaluate the effectiveness of insecticides and pesticides to prevent mosquitoes from developing immunity.

Looking ahead, Messenger emphasized that prevention and control will be vital to protecting both Las Vegas residents and the many visitors from around the globe.

“Ultimately, this situation is entirely preventable,” she asserted. “No one in southern Nevada, including Clark County, should suffer mosquito bites or risk contracting any virus.”

Source: www.nbcnews.com

Las Vegas Ends 214-Day Dry Spell with 0.01 Inch of Rainfall

Las Vegas – After a staggering 214 days without any measurable rainfall, the Las Vegas Valley finally saw some drizzle.

On Thursday, the National Weather Service recorded 0.01 inch of rain at Harry Reed International Airport, ending one of the longest dry spells in the city’s history.

This marks the first time in 88 years that Las Vegas has gone more than 200 days without rain, according to the National Weather Service. The last significant rainfall in the area was seven months ago, before July 13th, 2024.

While this dry spell broke records, the city’s longest stretch without measurable rain remains at 240 days, a drought that occurred in 2020.

The current winter season is uncharacteristically warm and dry in the region.

Almost all of southern Nevada is currently facing “extreme” drought conditions. The US drought monitors release color-coded maps weekly to show the severity of drought conditions nationally.

The most recent drought monitor map shows that over 88% of the state is experiencing some level of drought, with around 21% facing “extreme” or “exceptional” dryness.

Thursday’s rain extended across desert areas in the southwest, affecting much of southern Nevada, as well as parts of California and Arizona.

The Las Vegas branch of the Meteorological Bureau stated that due to months of dry weather, the exact amount of rainfall from this event remains uncertain. According to x.

Higher elevations are expecting snow, with winter storm warnings in place for Nevada’s Spring Mountain area until Friday afternoon. Weather services predict 12-24 inches of snow in the mountains, with snowfall potentially reaching above 8,000 feet.

The precipitation is part of a storm system moving through southern Nevada on Thursday and Friday.

The Weather Service forecasts Las Vegas could receive 0.5-0.9 inches of rain over the two days.

Source: www.nbcnews.com

Las Vegas sizzles in the heat

Las Vegas experienced its highest temperature on record on July 7, reaching 120 degrees Fahrenheit. The city surpassed a 2005 record of four consecutive days with temperatures above 115 degrees Fahrenheit on Wednesday, and then broke that record on Thursday, with Friday likely to follow suit. Extreme heat has been widespread across the Western U.S. this week, with around 42 million people under extreme heat warnings on Friday in the region, including the Rockies and southeast Texas. In at least six states, it is estimated that thirty-eight people have died from heatstroke.

“I’ve been a resident of southern Nevada in Las Vegas for 18 years, and this year has been exceptionally hot,” said Chrishell Hadsell, social services manager for Clark County, Nevada, encompassing Las Vegas, Boulder City, Henderson, and neighboring areas.

Hadsell is in charge of over 40 cooling centers currently in operation in Clark County, offering air-conditioned shelters in places like libraries, churches, and recreation centers for people to seek refuge during the hottest times of the day.

Record-breaking temperatures in Las Vegas are impacting people’s daily routines.

Henderson Fire Department Deputy Chief Scott Vivier mentioned that he and his wife now have to run errands and shop for groceries early in the morning to avoid the heat, as by 9:30 a.m., even being in the car can be intolerable.

“We’ve adapted to being active in the mornings and late evenings,” Vivier stated.

The extreme heat has led to multiple temporary closures at the Neon Museum near downtown Las Vegas this week.

“Due to the prolonged Extreme Heat Warning for the Las Vegas Valley, the Neon Museum will delay its opening until 8:30 p.m.,” officials announced on the museum’s website on Friday. The museum showcases some of Las Vegas’ most iconic and historic neon signs in its outdoor “curiosity yard.”

Despite the evening hours, visitors may still find it uncomfortable, as overnight temperatures this week have been in the 90s.

Similar extreme heat conditions prompted Henderson city officials to close the public pool early on both Thursday and Friday.

“Our inclement weather closure policy has been activated due to the extreme heat,” city officials noted in a Facebook post.

Source: www.nbcnews.com

Las Vegas sees surge in mosquitoes carrying West Nile virus

summary

  • A record number of mosquitoes in and around Las Vegas are testing positive for the West Nile virus as mosquito populations across the region soar.
  • Local health officials are urging residents to take precautions to avoid being stung.
  • The situation in Las Vegas is a case study as climate change expands the reach of vector-borne diseases.

Record numbers of mosquitoes are carrying the West Nile virus in and around Las Vegas, prompting local health officials to issue a public warning. Take precautions To avoid getting bitten.

West Nile virus causes fever, headache, vomiting and diarrhea and is fatal in about 1 in 150 cases. There is no vaccine or medicine to treat or prevent the mosquito-borne disease.

In recent weeks, 169 of more than 24,000 mosquito swarms tested for West Nile virus in 25 Southern Nevada ZIP codes tested positive, meaning at least one mosquito in the swarm was carrying the virus. The number of mosquitoes and positive swarms recorded this early in the season broke the regional records for both indicators set in 2019.

“The mosquito population is huge and we've already seen significant numbers of mosquitoes carrying the West Nile virus,” said Vivek Raman, environmental health inspector for the Southern Nevada Health Department.

Health officials also identified six swimming pools in the Las Vegas area where people had tested positive for the St. Louis encephalitis virus, a mosquito-borne disease that causes potentially fatal inflammation of the brain.

For decades, climate scientists and public health officials have warned that climate change could increase the range of various infectious diseases, particularly those transmitted by mosquitoes. The Las Vegas mosquito surge and regional increase in West Nile virus outbreaks provide an important case study in how climate affects human health.

Climate change will increase the global average temperature and precipitation, creating ideal conditions for mosquitoes, who breed in still, warm water. It will also lengthen the warm season, lengthening the mosquito season. These changes will Human exposure risk Even in places where no cases have been recorded before, there is an increased risk of contracting diseases such as West Nile virus.

The first case of West Nile virus was recorded in Las Vegas in 2004, five years after the first case in the United States was recorded in New York City in 1999. The most recent West Nile virus outbreak in Las Vegas was five years ago, when 43 people were infected, and area health officials fear the situation could get even worse this summer.

Spring weather is coming to Nevada and much of the Southwest. It gets warmer Summer heat waves have become more intense in recent decades. In Las Vegas, the average spring temperature is 6.2 degree increase since 1970This month, the city has already A week of record-breaking heatwave.

Rising temperatures in Southern Nevada are creating favorable conditions for mosquitoes, said Nishay Mishra, an assistant professor of epidemiology at Columbia University. Additionally, the state's ongoing drought has lowered groundwater levels throughout the Colorado River basin, including Lake Mead, which could unexpectedly benefit the insects.

“Mosquitoes typically breed in places that are moist and hot,” Mishra says, “but in Nevada, when small bodies of water dry up, they create shallow water that's perfect for mosquito breeding.”

Las Vegas' mosquito surge has been enormous: Last year, local health officials counted 6,000 mosquitoes in traps set across Clark County between April and June. This year, the number is already over 24,000.

Most of these mosquitoes are Culex mosquitoes, which are the primary vectors of the West Nile virus. But another mosquito species that doesn't carry the virus, Aedes aegypti, has also become common in Las Vegas. It was first spotted in the area in 2017, and Raman attributes its spread in part to climate change.

Along with climate, human behavior also plays an important role in the spread of vector-borne diseases. Culex mosquitoes and Culex pipiens mosquitoes breed in many Las Vegas backyards, the former breeding in small pools of water such as those left by sprinklers, and the latter often breeding along the surface of untended swimming pools.

Raman said the best ways to prevent infection are to empty water containers outside, take care of swimming pools, wear protective clothing and use bug repellent to prevent insect bites.

Louise Ivers, professor of global health and social medicine at Harvard Medical School and director of the university's Global Health Institute, said situations like the one in Las Vegas will become more common as infectious diseases continue to rise around the world due to climate change.

“We expect to see new infections, the resurgence of old ones, and changes in the transmission patterns of existing ones like West Nile virus,” Ivers said. “We may no longer be able to do things that we were previously free to do without worrying as much about protection from vectors like mosquitoes and ticks.”

Source: www.nbcnews.com

Cool Payment: LA’s Reflective Material to Beat the Heat and Stay Cool

In the Pacoima neighborhood of Los Angeles, Jose Damian, a street vendor for the past five years, braves temperatures of up to 105 degrees while selling Mexican snacks and shaved ice under the scorching midday sun. He recently experienced heat-related health issues when he felt dizzy and sweaty on his way to Sarah Coughlin Elementary School, prompting him to seek medical attention after losing all the salt in his body.

Residents in Pacoima have long endured extreme heat, with some taking multiple showers a day and struggling to stay cool due to the lack of trees and expensive air conditioning. The neighborhood holds the unfortunate title of being the hottest in Los Angeles and is disproportionately affected by heat-related illnesses, particularly in low-income communities of color like Pacoima.

A recent study shows that areas with a large Latino population, such as Pacoima, are significantly warmer than others in Los Angeles County. This disparity in temperature is exacerbated by the lack of tree canopies and green spaces in the neighborhood, further contributing to the heat island effect.

To combat the extreme heat, community organizations and local officials have joined forces to implement a cooling plan for Pacoima. Initiatives like the “Cool Pavement” project, in partnership with roofing manufacturer GAF, aim to reduce heat absorption in the neighborhood by repaving city blocks with solar reflective coating. This multi-year project not only helps cool the area but also adds vibrant murals and colored pavers to brighten up the community.

Source: www.nbcnews.com