From ABC 30
May 11, 2022

FRESNO, Calif. (KFSN) — Mosquito season is here. This means the West Nile Virus could be buzzing in your backyard.

“So this year, it’s a little early,” says Katherine Ramirez with the Consolidated Mosquito Abatement District. “We typically see positive mosquitoes in June.”

On Wednesday, the Fresno Mosquito and Vector Control District notified the Fresno County Department of Public Health of positive West Nile Virus cases collected in adult mosquitoes in Southeast Fresno.

While the Central Valley can be dry, Ramirez says any area in the Valley that has standing water can produce the potential for West Nile Virus-positive mosquitoes.

Ramirez advises folks to clean out or empty any standing water, including pools, the bottom of your plants and don’t forget to cover your yard drains.

West Nile can be a very serious illness and it only takes one bite to get sick.

Because there is no medication, health officials say prevention is key.

Read more

Posted by Vector and Vector-borne Disease Committee
May 9, 2022

West Nile Virus and Eastern Equine Encephalitis Virus High Probability Habitat Identification for the Selection of Sentinel Chicken Surveillance Sites in Florida

Sean P. Beeman¹; Joni A. Downs²; Thomas R. Unnasch¹; Robert S. Unnasch¹

¹Center for Global Health Infectious Disease Research, University of South Florida, 3720 Spectrum Boulevard, Tampa, FL 33612.

²School of Geosciences, University of South Florida, 4202 E Fowler Avenue, Tampa, FL 33620.

J Am Mosq Control Assoc (2022) 38 (1): 1–6.

https://doi.org/10.2987/21-7049

ABSTRACT [partial].  Identifying high probability locations for WNV and EEEV transmission and relocating coops to areas of higher arbovirus activity would improve the sensitivity of the sentinel chicken surveillance program. Using 2 existing models, this study conducted an overlay analysis to identify areas with high probability habitats for both WNV and EEEV activity. This analysis identified approximately 7,800 km2 (about 4.5% of the state) as high probability habitat for supporting both WNV and EEEV transmission. Mosquito control programs can use the map resulting from this analysis to improve their sentinel chicken surveillance programs, increase the probability of virus detection, reduce operational costs, and allow for a faster, targeted response to virus detection.

Note:  Because the number of locations sampled by sentinel chicken flocks always is limited by resources, sentinel programs should utilize a ‘best estimate’ approach with birds positioned in areas with a consistent history of enzootic virus activity to enhance the probability of seroconversions and therefore sensitivity.   Focal studies in the Coachella Valley (Reisen et al. 1995) similarly found that the incidence of seroconversions in sentinel chickens were dependent upon flock location and the frequency of serum collection. 

Reference List

Reisen, W. K., H. D. Lothrop, S. B. Presser, M. M. Milby, J. L. Hardy, W. J. Wargo, and R. W. Emmons. 1995. Landscape ecology of arboviruses in southern California: temporal and spatial patterns of vector and virus activity in Coachella Valley, 1990-1992.  J. Med. Entomol. 32: 255-266.

From CDPH VBDS
May 5, 2022

West Nile virus (WNV) has been detected in many regions of the state. Physicians should:

• Be aware if WNV is active in their area
• Look for symptoms of WNV
• Test for WNV because testing:
  • differentiates WNV from other conditions (enterovirus, other arboviral diseases) and thus may prompt a change in treatment regime
  • results offer anticipatory guidance–both WNV neuroinvasive disease and WN fever patients can have lingering symptoms and knowing the underlying etiology is helpful for the patient and family members
  • helps mosquito control and public health agencies institute proper control measures to reduce the risk of further cases in the event of a positive result
• Contact their local public health department for details on sample submission and testing

For additional information, please see these resources:

• WNV: Keep it on Your Radar (up to date clinical and epidemiologic presentation on WNV)
• Flyer for Physicians on West Nile Virus
• West Nile Virus Disease During Pregnancy
• West Nile Virus Information and Guidance for Physicians

Read more

From Action News Now
May 5, 2022

BUTTE COUNTY, Calif. – The Butte County Mosquito and Vector Control District will be checking unmaintained swimming pools and other “backyard breeders” through aerial surveillance on Monday.

Matt Ball, District Manager of Butte County Mosquito and Vector Control District, says it’s critical to check these areas early in the mosquito season when the West Nile virus is most active. Ball says it could prevent larger populations from hatching in urban areas later in the year.

“Undoubtedly the number of human cases could have been far worse in the state last year if it had not been for this program and others like it,” Ball said.

The Butte County Sheriff’s Office helicopter will assist with most of the flight during the project.

Read more

From the Fresno Bee
May 5, 2022

From KGET
April 21, 2022

BAKERSFIELD, Calif. (KGET) — Local experts say mosquito season is in full swing, and it will last until October or November. The Kern County Mosquito and Vector Control District says ankle-biting mosquitoes are back, but you can take steps today to keep them away from your home. Experts say a small, black-and-white mosquito called the Aedes Aegypti is already buzzing around Kern County.

“It’s a mosquito that not only will bite you multiple times, but it will bite you in the daytime,” said Terry Knight, of the Kern county Mosquito and Vector Control District. “It’s breeding in our front yards and our backyards. It’s going to be back, because we’re already seeing early numbers of this mosquito right now.”

Read more

From APB Live
April 20, 2022

New Delhi: Dengue is the most widespread mosquito-borne disease in the world, and is caused by dengue viruses, which is spread to people through the bite of an infected Aedes species (Aedes aegypti or Aedes albopictus). These mosquitoes also spread Zika, chikungunya, and other viruses, according to the Centers for Disease Control and Prevention (CDC). The transmission of dengue between humans is mediated by the bites of female Aedes aegypti mosquitoes.

About four billion people in the world live in areas with a risk of dengue. About 400 million people get infected with dengue each year. To date, there are no medical treatments for people suffering from this disease. 

The dengue virus causes symptoms ranging from high fevers to severe bleeding and shock, and can be life-threatening. Most common symptom of dengue is fever with nausea, vomiting, rash, or aches in the eyes, muscles, or joints. The disease presents an enormous burden on health systems. 

Read more

From KVTA
April 19, 2022

his is Mosquito Awareness Week and Ventura County Environmental Health officials are reminding us to take actions aimed at protecting ourselves and others from being bitten by mosquitos and also eliminating conditions that allow them to breed.

     They say make sure there is nothing in your yard that could collect even small amounts of water that can be used by mosquitos to breed.

     As far as avoiding being bitten, make sure you make it hard to allow mosquitos to enter your residence and wear protective clothing like long sleeve shirts and long pants.

     Also use EPA approved insect repellant.

     Mosquitos can transmit several diseases including West Nile Virus. 

     Below is the news release from Ventura County Environmental Health with more details…

Read more

From 23 ABC
April 19, 2022

Mosquito bites are not pleasant.

“It takes and wiggles that mouth pore through the threads in your clothing,” Michael Roe, a professor at the North Carolina State University Department of Entomology and Plant Pathology, said.

And sometimes, even a shirt can’t prevent them from getting to you. ”They can bite through animal fur, they can bite through your clothing,” Roe said.

But, at this lab, Roe and his team are developing something to change that, using mosquitos they raise in-house.

“We’ve been able to develop a series of parameters that every textile has, and by having the right combination of those parameters you can prevent a mosquito from biting through that textile,” he explained.

Read more

From the Culver City Observer
April 14, 2022

To celebrate the 70th anniversary of providing public health service, the Greater Los Angeles County Vector Control District (District) will host an open house at its Santa Fe Springs Headquarters on Saturday, April 16th from 10am to 2pm. For seven decades, the District has protected cities and communities from mosquito-borne diseases through surveillance, mosquito control, and public health education.

The free event is open to the public and will have food, music, activities for the whole family, and giveaways. The open house celebration is an opportunity for cities, elected officials, community partners, and residents to meet staff, learn about mosquito control, and explore the District’s facilities.

Read more

From Entomological Society of America Science Policy News
April 11, 2022

The Vector-Borne Disease Network (VBDN), a stakeholder group of nonprofit organizations including membership and trade associations, vector control groups, and educational institutions such as the Centers for Disease Control and Prevention Regional Centers of Excellence [Note: the PacVec Center is directed by faculty at UC Davis and Riverside], convened online as a group for the first quarterly meeting of the year on March 21. The VBDN invited Senate Health, Education, Labor, and Pensions (HELP) Committee majority and minority staff as special guests to speak to the group about S.3799, the “Prepare for and Respond to Existing Viruses, Emerging New Threats, and Pandemics Act” (PREVENT Pandemics Act), and ways the VBDN can help support their efforts.

While the bill is very broad in terms of public health priorities, specific to the interests of the VBDN are provisions that support biosurveillance, genome sequencing, a new epidemic forecasting center, loan forgiveness for public health professionals including vector management professionals (a program that has been authorized but unfunded previously), a new advisory committee to help improve communications during a public health emergency, a One Health Framework, and other ways to incentivize new talent in public health.

Caroline T. Weldon¹, Scott C. Weaver¹, and Kathryn H. Jacobsen²

¹ Western Gulf Center of Excellence for Vector-Borne Diseases and Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas; 

 ² University of Richmond, Richmond, Virginia

Am. J. Trop. Med. Hyg.  106: 1003-1004.  DOI: https://doi.org/10.4269/ajtmh.21-1340

Summary:  The COVID19 pandemic has caused major disruptions to medical and public health research productivity, especially among laboratory researchers.   These applied and academic public health workforce challenges have had a significant adverse impact on vector-borne disease (VBD) work in the United States over the past 2 years.   Based on responders to a small convenience survey, the authors observed the following trends:  1) Early in the pandemic, VBD personnel reported disruptions to the acquisition of biological specimens and laboratory equipment and supplies.  2) Much of the VBD workforce in 2020 were re-assigned to COVID-19 contact tracing and efforts on VBDs were reduced. 3) During 2020 and 2021 there was concern that VBDs were underdiagnosed and underreported, thereby reducing funding and resources for emerging VBDs.  4)  The responders felt that it will take several years for VBD research to regain momentum creating a decrease in publications reflecting the void in research.   

From the World Health Organization
April 7, 2022

In the lead-up to World Malaria Day 2022, we spoke with Dr Audrey Lenhart, Chief of the Entomology Branch in the Division of Parasitic Diseases and Malaria at the US Centers for Disease Control and Prevention (CDC) and incoming co-chair of WHO’s Vector Control Advisory Group (VCAG), about where we are in the global fight against malaria, some of the new innovations being developed to help manage the mosquitoes spreading the disease, and the role of VCAG in both expediting and assessing new technologies for WHO. This conversation has been lightly edited for concision and clarity.

Thanks for taking the time to talk today. First, could you tell us a little about your own background in malaria prevention and how you came to be a part of VCAG?

Sure. Before joining VCAG and even CDC, my background was more focused on Aedes aegypti control [the mosquito that transmits arboviral diseases such as Zika, dengue, chikungunya, and yellow fever] and insecticide resistance. Then when I joined CDC about 10 years ago, my work became much more focused on malaria.

I believe I was initially invited to participate in VCAG because I had experience with both Aedes control and malaria vector control, as well as experience in conducting large field trials of vector control tools with both entomological and epidemiological outcomes. That latter experience aligned particularly well with VCAG’s role in providing feedback to applicants on vector control trial design, and specifically around building a strong evidence base for understanding the public health impact of vector control tools.

Read more

From Recordnet.com
April 7, 2022

Crane flies, we’ve all seen them awkwardly bumping into walls, ceilings and windows, gathered around porch lights or stuck to your window screens. In our area, they commonly known as mosquito hawks or mosquito eaters, but did you know, they don’t actually eat mosquitoes.

Adult crane flies spend their very short lives with only love on their tiny minds. The sole purpose of the adult crane fly is to mate and, for the females, to lay eggs for next spring’s crop of flies. The adults don’t really eat at all but, they are undoubtedly greatly appreciated by hungry birds at this time of year, as well as smaller mammals, fish, spiders and predatory insects. Crane flies are harmless to handle, so the next time one makes its way indoors, simply cup it gently to release outdoors.  

Read more

From the Winters Express
April 7, 2022

The recent rain, combined with warm temperatures in the days ahead, make for the perfect breeding ground for mosquitos.

That’s why the Sacramento-Yolo Mosquito and Vector Control District is urging everyone to “drain the rain” to protect against mosquito-borne illnesses.

“Mosquitoes complete their life cycle much faster in warm weather,” said district manager Gary Goodman. “We urge all residents to do their part and help us drain standing water from common backyard sources such as buckets, flower pots, bird baths, old tires and other small containers that may breed mosquitoes.

“Getting rid of areas where mosquitoes can breed now will go a long way later in the season,” he added.

This is especially important for the prevention of invasive mosquitoes which have been rapidly spreading throughout the district since 2019.

Read more

From Pasadena Now
April 4, 2022

Extreme drought conditions have been prevalent across the San Gabriel Valley for years and now new research suggests that as the drought intensifies, the percentage of infected West Nile mosquitoes goes up.

A steady rise in infected mosquitoes in the Pasadena area has been documented since 2019.

Data provided by San Gabriel Valley Mosquito and Vector Control District (SGVMVCD) revealed that a total of 17 mosquito samples from San Gabriel Valley tested positive for WNV in 2019, 53 samples tested positive in 2020 while 190 samples tested positive in 2021.

This counterintuitive relationship between less water and more West Nile virus-carrying mosquitoes was described in 2017 by scientists who studied the relationship between climate change and the virus.

One of them, Sara Paull, a disease ecologist at the National Ecological Observatory Network in Boulder, Colorado, told Kaiser Health News the connection may have to do with birds.

Read more

Karen M. Holcomb,Chilinh Nguyen,Brian D. Foy,Michelle Ahn,Kurt Cramer,Emma T. Lonstrup,Asli Mete,Lisa A. Tell,Christopher M. Barker https://doi.org/10.1371/journal.pntd.0010260 

Author summary:

Current mosquito control strategies aimed to prevent pathogen transmission to humans have limited ability to target mosquitoes involved in amplification and spillover transmission of pathogens like West Nile virus (WNV). Additionally, growing prevalence of insecticide resistance in mosquito populations limit the efficacy of these insecticide-based control strategies. Ivermectin (IVM) provides an alternative avenue for control by increasing the mortality of mosquitoes that ingest this drug in bloodmeals. Therefore, IVM treatment of avian species that account for the majority of mosquito bloodmeals during the WNV transmission season could be an effective control strategy. Building on pilot studies indicating the efficacy and feasibility of IVM-deployment for WNV control, we performed a randomized field trial to investigate the impact of IVM-treatment of backyard chickens on local population dynamics of Culex mosquitoes and WNV transmission. We were able to link changes in mosquito populations to reduction in WNV transmission, as measured by chicken seroconversions, through IVM-induced mortality in mosquitoes. However, further work is needed to identify the impact of treatment on mosquito abundance and infection prevalence to fully attribute observed changes to IVM administration. Overall, our results support IVM treatment as a potentially effective alternative to insecticide-based vector control strategies and one that can be used to target WNV transmission on the local scale.

Based on this positive pilot study with sentinel chickens, the authors suggested future research should entail treating peridomestic passerines attracted to backyard bird feeders as a possible approach to reducing the infectious vector population

From the Davis Enterprise
March 31, 2022

The recent rain, combined with warm temperatures in the days ahead, make for the perfect breeding ground for mosquitos.

That’s why the Sacramento-Yolo Mosquito and Vector Control District is urging everyone to “drain the rain” to protect against mosquito-borne illnesses.

“Mosquitoes complete their life cycle much faster in warm weather,” said district manager Gary Goodman. “We urge all residents to do their part and help us drain standing water from common backyard sources such as buckets, flower pots, bird baths, old tires and other small containers that may breed mosquitoes.

“Getting rid of areas where mosquitoes can breed now will go a long way later in the season,” he added.

This is especially important for the prevention of invasive mosquitoes which have been rapidly spreading throughout the district since 2019.

Read more

From ABC10
March 30, 2022

SAN DIEGO (CNS) — Scientists at the University of California San Diego received a $1.4 million grant to study new genetic technologies intended to curb mosquito populations and fighting the spread of malaria, it was announced Wednesday.

The Bill & Melinda Gates Foundation grant will also allow researchers to mitigate hazards associated with using gene-editing systems in the wild, according to UC San Diego.

“My lab, historically, was a fruit fly lab,” said Ethan Bier, a UC San Diego distinguished professor of developmental biology and science director for the Tata Institute for Genetics and Society.

“About five years ago in collaboration with the laboratory of Anthony James at UC Irvine, we started transferring some of our genetic strategies into mosquitoes,” Bier said in a statement.

Read more

From LAist
March 28, 2022

Michael Keasling of Lakewood, Colorado was an electrician who loved big trucks, fast cars and Harley-Davidsons. He’d struggled with diabetes since he was a teenager, needing a kidney transplant from his sister to stay alive. He was already quite sick in August when he contracted West Nile virus after being bitten by an infected mosquito.

Keasling spent three months in hospitals and rehab, then died on Nov. 11 at age 57 from complications of the virus and diabetes, according to his mother, Karen Freeman. She said she misses him terribly.

“I don’t think I can bear this,” Freeman said shortly after he died.

Spring rain, summer drought and heat created ideal conditions for mosquitoes to spread the West Nile virus through Colorado last year, experts said. West Nile killed 11 people and caused 101 cases of neuroinvasive infections — those linked to serious illness such as meningitis or encephalitis — in Colorado in 2021, the highest numbers in 18 years.

From Spectrum News 1
March 28, 2022

Temperatures have climbed higher and higher in the spring season for most of the country over the past half-century. While that might mean you can put away the heavy coat sooner, you might have to reach for the allergy medicine sooner, too.

Since 1970, all but a part of the Northern Plains have seen springs trend warmer. The Southwest had the greatest warming, with some cities going up by about six degrees.

Read more

From SCV News
March 24, 2022

The city of Santa Clarita invites residents to participate in the Rain Barrel Purchase Program. Residents can pre-order up to two rain barrels per household for $40.00 each, plus tax, at bit.ly/rainbarrelsc3 for pickup on Saturday, April 2, from 9:00 to 11:00 a.m. at The Centre at 20880 Centre Pointe Parkway.

Rain barrels are an effective way to capture rain water to be stored and used for multiple purposes including home gardening projects and other household tasks. Each rain barrel is made out of food-grade plastic with a solid brass spigot that can be used to attach a garden hose to divert water for landscape irrigation. The barrel is also topped with a four-inch mesh screen that prevents bugs from contaminating the water and comes in 50-60-gallon capacity.

Read more

From MedicalXpress
March 21, 2022

Scientists at the University of Glasgow and partner institutes have developed an inexpensive, fast and simple way to identify the aging mosquitos which transmit the deadly malaria parasite.

The study—published today in Nature Communications and led by the University of Glasgow-Institute of Biodiversity Animal Health and Comparative Medicine (IBAHCM) and School of Chemistry, and the Ifakara Health Instititute (IHI) in Tanzania and the Institut de Recherche en Sciences de la Santé (IRSS) in Burkina Faso—presents a step change in our ability to accurately identify the age and species of malaria mosquitoes in wild populations, where it is critically important to be able to monitor their age, as only old mosquitoes can transmit the disease.

In 2020, there were an estimated 241 million cases of malaria worldwide, according to the WHO, killing around 627,000 people; and while there are vector controls in place to reduce the numbers of mosquitos that transmit the disease in certain parts of the world—such as insecticides or bed nets—the effectiveness of these interventions can be hard to measure.

Read more

Journal of Medical Entomology
Volume 59, Issue 2, March 2022

Sheppard, J.G. 2021.  Record Longevity and Reproduction of an African Tick, Argas brumpti (Ixodida: Argasidae). J. Med. Entomol. [https://doi.org/10.1093/jme/tjab205].

Abstract:  Argas brumpti Neumann is a large argasid (soft) tick that inhabits the drier areas of eastern and southern Africa. This species typically feeds on a wide variety of small to large mammals (including humans) and lizards, and resides in shallow caves, rocky areas, or dust-bath areas used by large mammals. Individuals of this species, collected as nymphs and adults from a semidesert area of Kenya and subsequently maintained under constant conditions in the laboratory, survived for 27 yr. Furthermore, after 8 yr of starvation and at least 4 yr after the last male died, at least one female laid eggs. The progeny developed into considerable numbers of both males and females, some of which are still living after 26 yr. The longevity of these ticks is apparently a record for any species of tick. The delay in reproduction likely represents long-term storage of viable sperm, also apparently a record for any species of tick. 

The bionomics of this species of Argasidae is similar to that of the Pajahuello tick Ornithodoros coriaceus that is found in the foothills of California in and around deer and cattle bedding areas, where it is the known vector of the deltaproteobacterium that causes Epizootic Bovine Abortion.   Addressing this cattle industry problem was one the primary reasons for establishing the UC School of Veterinary Medicine at Davis. 

From the New York Times
March 14, 2022

Public health measures to stop the spread of Covid-19 had an unintended consequence across Latin America and Southeast Asia in 2020: Dengue virus infections were prevented in hundreds of thousands of people, according to a study published in The Lancet this month. The research offers clues for new strategies to combat a dangerous tropical disease that had been infecting more people each year.

The research found a marked decline in infections from April 2020 across many regions where dengue is spread by mosquitoes; the study estimates that there were 720,000 fewer dengue cases globally in the first year of the pandemic because of restrictions on movement.

Read more

From ESA Science Policy News
March 10, 2022

Congress has continued to kick the appropriations can down the road for fiscal year (FY) 2022, with a series of Continuing Resolutions (CRs), the latest of which is set to expire tomorrow, March 11. The Vector-Borne Disease Network (VBDN) sent a letter to the House and Senate Appropriations Committees, as well as other relevant Congressional supporters, asking them to finalize the spending bills for FY 2022, rather than continuing to operate under ongoing CRs, and to support the $15 million in the House bill for the CDC Centers of Excellence on Vector-Borne Diseases.

The PacVec Center of Excellence at UC Davis and UC Riverside are funded through this CDC mechanism. 

From ABC News
February 17, 2022

Mosquitoes may be smarter than we think, and that could make getting rid of them and the diseases they carry even more difficult, according to new research.

Scientists who studied two species of mosquitoes that spread diseases such as dengue, Zika and West Nile fever — Aedes aegypti and Culex quinquefasciatus — found that the females learned to avoid pesticides after a single non-lethal exposure, a study published Thursday in Nature found.

The researchers exposed the female mosquitoes to non-lethal doses of common anti-mosquito pesticides and found that mosquitoes that had been pre-exposed to a pesticide avoided passing through a pesticide-treated net in order to reach a food source at a higher rate than those who had not been pre-exposed, according to the paper.

In addition, the survival rate of pre-exposed mosquitoes was more than double that of mosquitoes that had not been pre-exposed.

Read more

From the Colusa County Sun-Herald
February 16, 2022

As the weather begins to warm up, the Colusa Colusa Mosquito Abatement District is gearing up for the upcoming mosquito season and asking local residents to do their part.

“The effort consists primarily of a spray program to control adult mosquitoes using truck mounted foggers in both the urban and rural areas of the District, starting in late May,” said Colusa Mosquito Abatement District Manager Dan Kiely. “Control measures will only take place within the boundaries of the District which only include the town of Colusa and outlying areas around the town.” 

The District covers 160 square miles, with 20 square miles located in Sutter County. 

Kiely said aerial control of adult mosquitoes will also be conducted by aircraft in the wetland and duck club areas within the District utilizing materials registered with the Environmental Protection Agency. 

“The District also has a Larvacide program to control the immature stages of the mosquito, and will place larvicides in the catch basins throughout the District during the later spring months,” said Kiely. “Catch basins that maintain standing water throughout the mosquito season can be a major source of urban mosquitoes.” 

Read more