Invasive plants boost mosquitoes in low-income areas of Baltimore and DC

Cary co-authored paper suggests planting native trees can help reduce mosquitoes and protect against mosquito-borne disease.

Cary Institute of Ecosystem Studies

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Credit: Credit: Edwin Remsberg / University of Maryland

In many urban areas, low-income neighborhoods have more mosquitoes, making residents more vulnerable to mosquito-borne diseases. A new study co-authored by scientists at Cary Institute of Ecosystem Studies found that invasive, nonnative plants, which tend to be more common in low-income areas, boosted mosquito populations in Baltimore, MD, and Washington, DC. 

Lead author Sarah Rothman, a former postdoctoral researcher at the University of Maryland, explains, “Leaves that decay in water-holding containers provide the resources that mosquito larvae eat. Our study showed that the leaves from canopy trees more commonly found in low-income neighborhoods helped boost mosquito growth in ways that were measurable and significant.”

The research team found these mosquitoes were more likely to survive and reach adulthood sooner. One of the mosquito species also had larger wings as adults compared to mosquitoes reared with leaves more common to higher-income neighborhoods. Wing length indicates body size in mosquitoes, and larger-bodied mosquitoes are better at transmitting disease.

The results, published in the Journal of Medical Entomology, suggest that cities and their residents could reduce mosquito infestations by planting native tree species.
 

Mosquito mystery

The new paper builds on research that Cary Institute disease ecologist and co-author Shannon LaDeau started in 2011 in Baltimore as part of the Baltimore Ecosystem Study. Over the years, LaDeau and collaborators have investigated how the social and ecological environment shape people's experiences with invasive mosquitoes in urban settings, documenting interactions between socioeconomics, vegetation, and mosquito traits.

Mosquito larvae eat bacteria that grow on decomposing matter. In urban areas, this often means plant litter that falls into water-filled containers such as tires or trash cans. But a few years ago, LaDeau and colleagues noticed a discrepancy: In Baltimore, higher-income areas had more abundant and more diverse tree canopies, whereas low-income areas had more abundant and larger mosquitoes that are better at transmitting disease. 

“We wanted to understand if differences in tree canopy might help explain why we found more abundant and larger mosquitoes in some neighborhoods,” explained LaDeau, whoco-advised Rothman’s PhD research. “Our earlier studies demonstrated that you're more likely to find nonnative plants in neighborhoods with lower housing values and more abandoned lots. These fast-growing species tend to take over when land is vacant, whereas wealthier neighborhoods have the resources to establish and maintain slower-growing native trees. Decades of municipal and state disinvestment in low-income neighborhoods plays an important role in this disparity.”

 

Testing tree leaf teas

To investigate how different tree species affect mosquito growth and survival, the researchers tested mixtures made from the leaves of the most common trees in low- and high-income areas in Baltimore and Capitol Heights, MD, and Washington, DC. 

One mixture contained leaves from the two most prevalent trees in low-income areas: tree-of-heaven and princess tree, both introduced species. The second was made from leaves of American elm and red maple, both native species that were among the most widespread trees in wealthier neighborhoods. And the third contained leaves of two species found in both high- and low-income areas: white mulberry (nonnative) and black walnut (native). 

After soaking the leaves in water for five days, the researchers added larvae of two species of invasive mosquito: Asian tiger mosquito (Aedes albopictus, which spreads diseases including dengue, Zika, yellow fever, and other diseases) and the common house mosquito (Culex pipiens, a vector of West Nile and other harmful viruses). Some of the cups contained just one of the mosquito species, and others contained both to measure how the mixtures influenced mosquito competition. Over time, the mosquito larvae ate the bacteria that had been breaking down the wet leaves, and the researchers measured how well the young mosquitoes survived and grew. 

“The hardest part of doing this type of lab experiment,” said Rothman, “was getting hundreds of mosquito eggs to hatch in synchrony so we could start many containers at the same time for comparison.”
 

Novel strategies for managing mosquitoes

“Mosquito growth and survival were significantly enhanced when reared on leaf mixtures that contained at least one nonnative tree species,” said LaDeau. “We also found that the nonnative vegetation may reduce competition between the two mosquito species, allowing them to coexist in low-income areas.”

The researchers conclude that the disproportionate amount of introduced plants in low-income areas may help support high mosquito populations, potentially putting local residents at greater risk for mosquito-borne diseases. 

“Scientists have found multiple reasons that explain why mosquito infestations are worse in low-income areas, often having to do with quantity — for example, more containers to breed in or more rats to feed on,” said Rothman. “We’re showing that quality matters, too. Municipal governments and residents can use this information when deciding which trees to plant along streets or in yards.”

Introduced plants may have boosted mosquito populations because of their high nitrogen content, which not only makes them easier to digest, but also helps the leaves decay faster, making nutrients available to microbes sooner compared to leaves from native plants. Another possibility is that, because the invasive plants and invasive mosquito species in this study shared native habitats in China, the mosquitoes may be adapted to thrive among these plants.

As a next step, the researchers hope to repeat their tests with other tree species, to see if the findings hold up, said Rothman. 

Interestingly, cups with native and nonnative leaves supported similar microbial abundance, but this experiment did not examine which types of microbes were present in the different treatments. “In future studies, we aim to dive deeper into the microbial communities to see whether certain types of microbes make better or worse food sources for mosquitoes,” said coauthor Jane Lucas, a community ecologist at Cary Institute. 

LaDeau added that future studies should test whether the effects found in this study translate into greater mosquito survivorship and fitness in real-world neighborhoods, and whether leaf types influence mosquitoes’ ability to spread disease.

“Our findings suggest that mosquito control agencies could better predict where infestations may occur by surveying the local vegetation,” said LaDeau. “They also provide hope that governments and city residents can protect public health in low-income communities by replacing nonnative plants with native ones.” 

 

Authors

Sarah Rothman - University of Maryland

Shannon LaDeau - Cary Institute of Ecosystem Studies

Jane Lucas - Cary Institute of Ecosystem Studies

Paul Leisnham - University of Maryland

 

Funding

The research was supported in part by the National Science Foundation (grant DEB-1824807), the Cary Institute of Ecosystem Studies through the Lang Assael Family Science Innovation Fund and the Bentley Holden Scholarship, and the Washington Biologists' Field Club.

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Cary Institute of Ecosystem Studies is an independent nonprofit center for environmental research. Since 1983, our scientists have been investigating the complex interactions that govern the natural world and the impacts of climate change on these systems. Our findings lead to more effective resource management, policy actions, and environmental literacy. Staff are global experts in the ecology of:  forests, freshwater, soils, cities, and disease.

  

Leaves soaked in water provided microbial food for mosquito larvae

Credit

Credit: Edwin Remsberg / University of Maryland

 

Mosquitoes raised on leaf litter from low-income areas were more likely to survive, reach adulthood sooner, and, for one of the mosquito species, also had larger wings as adults compared to mosquitoes in containers with leaves more common to higher-income neighborhoods. 

Credit

Credit: Sarah Rothman

Sarah Rothman in front of a chamber used to rear mosquitoes. 

Credit

Credit: Edwin Remsberg / University of Maryland

Journal

Journal of Medical Entomology

DOI

10.1093/jme/tjag081 

Article Title

Leaf litter characteristic of low-income urban blocks improves population performance of Aedes albopictus (Diptera: Culicidae) and Culex pipiens mosquitoes

 

2 million cars with anti-theft systems installed by dealers are at higher risk of theft

A vulnerability in systems installed by dealers in Southern California since 2017 is getting fixed by the system manufacturer. But car owners need to be aware.

University of California - San Diego

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This sticker, found on cars sold after 2017 on the driver’s side window, indicates that the vehicle likely has had a vulnerable system installed by a dealer. 

 

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Credit: David Baillot/University of California San Diego/Jacobs School of Engineering

Video: https://youtu.be/xS_4dNRGkoA?si=olL6w75Gj9l0DQo8

At least 2.2 million cars on the road today are vulnerable to an attack that allows thieves to lock and unlock doors and immobilize vehicle engines remotely via a Bluetooth connection, computer scientists at the University of California San Diego have found. 

Attackers can get access to cars from as far as five yards away. Most of the vulnerable vehicles were bought at Honda, Toyota, Mazda, Ford, and Jeep dealerships in Southern California from 2017 to today. But because these vehicles are resold on the second-hand market, several hundred thousand vulnerable vehicles can also be found throughout the United States, Canada and even as far as Japan. Many vulnerable cars display a sticker with the word “KARR” or “SWDS” on the driver’s-side window. 

The vulnerability is due to a device controlled via a smartphone app that is typically installed by dealerships to manage vehicle inventory and prevent theft. The device, installed underneath the bottom of the dashboard on the driver’s side, connects vehicle and app via Bluetooth. The app makes the device perform functions similar to a key fob: lock and unlock doors as well as honk a horn and flash headlights as a warning. In addition, the device can prevent the car from starting as long as the car isn’t already running. 

All KARR-SWDS devices rely on the same secure key – meaning that once the researchers cracked that key, they had access to all the cars equipped with these devices. It’s a bit like setting all passwords for a line of devices to 1234 and making it impossible to change the password. 

When a dealership sells a vehicle, they market the device and app as a paid upgrade – an anti-theft tool as well as a tool to control the car via an app. Even if the buyer declines the upgrade, the device remains active, still leaving the vehicle vulnerable to an attacker in certain situations. 

The company manufacturing these devices, Acrisure, released a patch to fix the vulnerability on July 20, 2026. The fix requires downloading an app. “Many car owners don’t even know that their vehicle is vulnerable. So we wanted to make sure they were aware by publishing this study,” said Aaron Schulman, a professor in the UC San Diego Department of Computer Science and Engineering, and one of the study’s senior authors.

The vulnerability could allow thieves to steal cars more easily. “Instead of smashing a window to get access to a vehicle, thieves could simply connect remotely via Bluetooth to the device inside the vehicle, and make it unlock car doors,” said Jerry Yu, a computer science Ph.D. student in Schulman’s research group at UC San Diego and the paper’s co-first author. Once the car is unlocked, attackers can use a variety of tools available to locksmiths to then start the car and drive away. 

The researchers, led by Schulman, will detail how they discovered the vulnerability and reverse-engineered it at the DEF CON conference Aug. 9 in Las Vegas and the USENIX Security conference Aug. 12 in Baltimore, Md. 

In the study, researchers identified at least 1.4 million vulnerable vehicles, but further analysis by the UC San Diego researchers increased that number to an estimated 2.2 million – at least. 

Different levels of vulnerability

In addition to Acrisure, Rockledge, a car security and insurance company, makes similar devices. The researchers found these devices may also be vulnerable, but are more difficult to attack. An attacker would need to be there when a driver uses these systems to intercept and record their digital interactions, and then play those interactions back to get access to the user’s vehicle. Researchers were unable however to validate these findings with Rockledge as the company had not yet responded to the researchers’ disclosure as of this writing. 

The research team is careful not to disclose the details of how they reverse-engineered the systems so their work can’t be replicated by thieves. Researchers also disclosed the vulnerabilities to all relevant manufacturers and vendors as well as to the National Highway Traffic Safety Administration. 

How to fix the vulnerability? 

“Removing the devices is not trivial. You have to open up the dashboard and cut and reconnect the wires that are deeply intertwined with the car’s computers and ignition system,” said Yibo Wei, who is also a computer science Ph.D. student  in Schulman’s group at UC San Diego and the paper’s co-first author. 

To fix the vulnerability non-invasively, the device firmware – the software that controls the hardware – needs to be updated. On July 20, KARR-SWDS maker Acrisure announced that it has released a firmware update to fix the issue. The update needs to be made by the vehicle owner via the KARR app. For more information visit www.KARRsecurity.com  

But to truly make sure similar vulnerabilities do not occur in the future, researchers suggest that physical interaction – like pressing a button inside a car – be required when a new smartphone connects with these Bluetooth-based security systems. 

How did the researchers discover the vulnerability? 
It all started in 2018 when researchers led by former UC San Diego computer science Ph.D. student Nishant Baskar found Bluetooth fingerprints they didn’t recognize while hunting for devices called credit card skimmers, which criminals install in gas pumps to steal consumer credit and debit card data. 

After a fair bit of research, they were able to connect the Bluetooth fingerprints to the devices manufactured by Acrisure and Rockledge. They then set out to test whether the devices were secure, as part of a broader research effort to understand cybersecurity in Bluetooth devices. 

Researchers also found that public databases store location information about vehicles equipped with these devices. This in turn, would allow attackers to track specific vehicles they want to break into. 

The research was supported in part by a grant from the National Science Foundation (grant no. CNS-2239163).

BLE Theft Auto: Evaluating the Security of Aftermarket BLE-based Automotive Remote Control Systems 

Jerry Yu, Yibo Wei, Sumanth Rao, Mohak Vaswani, Jefferson Chien, Nishant Bhaskar and  Aaron Schulman, Department of Computer Science and Engineering, University of California San Diego, UC San Diego, Christian Dameff, UC San Diego Health

This button is part of the KARR system. If it is installed in your car at the bottom of the dashboard, your car is likely vulnerable to the attack the researchers have discovered. 

 

Yibo Wei, a Ph.D. student at UC San Diego and one of the paper’s co-first authors, holds up a phone equipped with an app he built to exploit the vulnerability the researchers discovered and gain unauthorized access to a car. 

This button is part of the KARR system. If it is installed in your car at the bottom of the dashboard, your car is likely vulnerable to the attack the researchers have discovered. 

 

Credit

David Baillot/University of California San Diego/Jacobs School of Engineering

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

BLE Theft Auto: evaluating the security of aftermarket BLE-based automotive remote control systems

New research finds that dropping SAT and ACT requirements may improve access, but may also hinder college admissions

Institute for Operations Research and the Management Sciences

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BALTIMORE, July 16, 2026 — Dropping standardized testing requirements may make admission to college more accessible for some, but it can also make it harder for universities to identify high-potential students, according to new research published in the INFORMS journal Management Science.

That research suggests the decision involves nuanced tradeoffs between the informational value of test scores and barriers to access. Moreover, the study shows that dropping the testing requirement can even move diversity and academic merit in the same direction: it is possible to improve both, or worsen both, at once.

The study, "Dropping Standardized Testing for Admissions Trades Off Information and Access," develops a statistical discrimination framework that shows that if you drop a feature like test score review, this could impact the context with which you then see all of the other data used in the review and vetting process. Holistically, the review process depends on the information provided by other application components and how, collectively, that requirement shapes the applicant pool.

The findings add important nuance to ongoing policy debates in higher education: removing standardized testing may expand access for underrepresented groups but can also reduce the ability to accurately assess academic merit, particularly for students from nontraditional backgrounds. In some settings, it improves diversity and merit simultaneously; in others, it worsens outcomes across multiple metrics.

“The decision to drop standardized testing involves a fundamental tradeoff between information and access,” said Nikhil Garg of Cornell University, a co-author of the study. “Test scores provide valuable signals, especially when other parts of the application are less informative for certain groups of students, but access barriers can prevent some qualified students from even applying.”

The study examined the admissions process where schools evaluate applicants based on multiple features, such as grades, recommendation letters, essays, and test scores, while considering capacity constraints and fairness goals. The researchers examined both non-strategic access barriers and strategic student behavior. Using calibrated simulations, the authors demonstrated practical scenarios where outcomes would vary significantly.

“Our results showed that dropping the test can exacerbate disparities by decreasing available information, especially for nontraditional applicants,” said Hannah Li of Columbia Business School, a study co-author. “Still, when access barriers are substantial, removing the test scores requirement can expand the pool in ways that may improve both merit and diversity.”

The study further shows that student test-taking behavior may have some counterintuitive effects, complicating admissions decisions. This is particularly the case in multi-school settings where you may have one school applying a more restrictive standard, and another competing school, applying a less restrictive acceptance standard. The study shows that when some schools drop the test and others keep it, some qualified students may opt out of testing entirely, missing the chance to apply to schools they otherwise would have been admitted to.

“Our findings suggest that policymakers and admissions offices need to jointly consider the informational environment and access barriers rather than viewing the testing requirement decision in isolation in a 'tests good vs. tests bad' manner,” said Faidra Monachou of Yale School of Management, a study co-author. “These decisions affect not just who gets admitted, but also who gets to apply in the first place, and ultimately the academic merit and diversity of the admitted class.”

The study raises important questions about how institutions can balance competing goals, where colleges and universities seek to balance access, merit, and diversity. In the end, the study authors concluded that schools may benefit from investing in better signals for all applicants, while still working to reduce access barriers, instead of just dropping test score requirements.

Read the full study here.

About INFORMS and Management Science

INFORMS is the world’s largest association for professionals and students in operations research, AI, analytics, data science and related disciplines, serving as a global authority in advancing cutting-edge practices and fostering an interdisciplinary community of innovation. INFORMS empowers its community to improve organizational performance and drive data-driven decision-making through its journals, conferences and resources. Learn more at www.informs.org or @informs.

Management Science, a leading journal published by INFORMS, publishes research on decision sciences, strategy, innovation and quantitative methods that inform managerial and policy decisions.

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Journal

Management Science

DOI

10.1287/mnsc.2023.02573 

Article Title

Dropping Standardized Testing for Admissions Trades Off Information and Access

‘Another Shitty Situation’: 💩

Trump Attack on CDC Monitoring Blamed in ‘Explosive Diarrhea’ Outbreak

“The catastrophic cuts Trump and RFK Jr. made to disease surveillance and research keep coming back to haunt us,” said one critic.


US Health and Human Services Secretary Robert F. Kennedy Jr. listens during a tour of the kitchen at Cunningham Elementary School in Austin, Texas on February 27, 2026.
(Photo by Jay Janner/The Austin American-Statesman via Getty Images)

Brad Reed
Jul 14, 2026

COMMON DREAMS

The Trump administration is coming under fire for its response to the outbreak of cyclosporiasis, a foodborne illness that causes explosive diarrhea and has so far been documented in more than two dozen states.

Public health officials still have not identified the source of the outbreak, which typically spreads via contaminated produce.

In an interview with Axios published Saturday, David Freedman, professor emeritus of infectious diseases at the University of Alabama at Birmingham, suggested that the US Centers for Disease Control and Prevention (CDC) has not been on top of tracking the outbreak the same way it has been in the past.

“Right now it’s individual state health departments that are having to speak up,” remarked Freedman, “because the CDC is really not following it on a day-to-day basis.”

Omer Awan, vice chair and associate program director for the diagnostic radiology residency at the University of Maryland School of Medicine in Baltimore, told PBS in an interview published Monday that infections will likely only grow if the government doesn’t track down the source of the outbreak quickly.

“Because we haven’t pinned it down, that means that these cases are likely to disseminate,” said Awan. “People are still eating the contaminated food that’s leading to so many cases.”

Awan added that mass firings at the US Department of Health and Human Services (HHS), under the leadership of anti-vaccine conspiracy theorist Robert F. Kennedy Jr., were hindering CDC’s ability to track the disease.

“The HHS and the federal government laid off a lot of CDC employees,” said Awan. “Many of them were the very employees that would track these particular outbreaks. And the other is that, from July of 2025 last year, the CDC has no longer required reporting cyclosporiasis. It’s become optional to report this to the CDC’s Foodborne Disease Active Surveillance Network.”

Brad Woodhouse, president of Protect Our Care, pointed to the CDC decision to stop monitoring the cyclospora parasite as an example of the Trump administration putting Americans “in another shitty situation after laying waste to our public health infrastructure and gutting emergency preparedness.”

“Because RFK Jr.'s CDC turned a blind eye to dangerous foodborne pathogens,” Woodhouse added, “this outbreak spread quickly and states are now scrambling to do their own detective work on what’s causing it. The catastrophic cuts Trump and RFK Jr. made to disease surveillance and research keep coming back to haunt us, yet they want to cut even deeper to make up for their tax breaks for billionaires.”

The Washington Post on Tuesday reported that both federal and state officials have launched an investigation into whether fast food chain Taco Bell “played a role” in the cyclosporiasis outbreak.

According to the Post’s sources, some people who got sick from the disease said they had eaten at Taco Bell shortly becoming symptomatic, although others who were infected by the parasite said they had not eaten at the fast food chain before growing ill.

“Public health officials have said this season’s unusually high number of illnesses, now reported in more than 30 states,” reported the Post, “means more information and more patients to help identify shared foods, shopping habits and restaurant visits among those sickened to help determine the source.”

Expert details 'red herring' hiding real issue behind parasite outbreak

Image via Shuttertstock

Thomas Kika

July 15, 2026

ALTERNET


An expert in infectious diseases this week tossed cold water on the hype and panic surrounding the recent parasitic outbreak, arguing that certain reports about Trump administration cuts have been a "red herring" masking the real issue and making things worse.

As of Tuesday, NBC News reported that around an estimated 7,000 cases of cyclosporiasis had spread across the U.S., according to data from the Centers for Disease Control and Prevention, with a little over 3,300 being from Michigan. A parasitic foodborne illness, cyclosporiasis can cause days or weeks of severe explosive diarrhea, and is most often spread by contaminated fresh produce, including leafy greens, berries and herbs.

Since the outbreak began to emerge, reports have indicated that the sweeping cuts to the national health and disease tracking apparatuses under President Donald Trump have made the situation worse, with many reports honing in on a change made to FoodNet last year. Introduced in 1995, FoodNet is a program run in collaboration between the CDC, the Department of Agriculture, the Food and Drug Administration and state health departments, which aims to track the spread of foodborne diseases. In 2025, under the Trump administration, the tracking of cyclosporiasis was made optional.


In a Wednesday appearance on CNN, Michael Osterholm, an epidemiologist and director of the Center for Infectious Disease Research and Policy at the University of Minnesota, told host Audie Cornish that the attention put on that FoodNet change was a "red herring," as far as this current outbreak was concerned. He also said that, by his estimation, the outbreak was most likely done, for the time being.

"There's a lot of misinformation going around about this right now," Osterholm said. "Let me tell you, I'm not afraid to be critical of the federal government or even state governments with regard to response. But let's be really clear: the changes that occurred at CDC were eliminating certain diseases from what would be considered community laboratories, the FoodNet system. These are ten sites where they do much more extensive study. The way cases get reported to local and state health departments, and the CDC, through the national notifiable disease system, that has not changed. So this idea that somehow what changes occurred at CDC basically caused this outbreak not to be well investigated, just simply [isn't] true."


He also noted: "I can say right now, I think the outbreak is over. And what I mean by that is the perishable items that came through the food system 4 to 6 weeks ago are gone. It's not there anymore. People are still sick. We're still going to hear about new cases because they're just now getting diagnosed. And as you heard on the lead-in on the social media commentary, we just heard, there are people who are still very sick. The good news is they can be treated. The really also good news is that leafy greens generally are very safe to eat."

While dismissive of the focus put on the FoodNet changes as a contributor to this outbreak, Osterholm was still critical of the CDC's response time, as well as

"I think this outbreak is one that really needs to be reexamined when it's all done, because I think, frankly, we should have had these answers weeks ago and didn't," Osterholm explained. "And I can't attribute that to any one thing other than a lack of overall leadership in responding to this. Yesterday, the CDC put out what was called a 'health alert network' alert, and at that point, that's something that should have been sent out four weeks ago, not at the end of this."


He added later: "The problem we have is that in the first instance, like politics, all of foodborne disease investigations start at the state and local level. And today, 94 percent of all the budgets for all 50 state health departments depend on this federal support to achieve that level of protection. And right now, we're having challenges at the state and local health department where, in fact, these investigations begin. So that is a problem. But it's not what has been made.The problem with this FoodNet system, that's just a red herring."