Mosquito & Vector News

Here’s what the first year of Zika looks like

From Yahoo News
January 7, 2021


The Zika virus came seemingly out of nowhere and broke all the rules. Here’s a look at the plot twists during the first year of the virus – and where it’s going next.

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New defense against dengue and emerging mosquito-borne viruses

From EurekAlert
January 7, 2021

New treatments to cut the global death rate from dengue, Zika and West Nile viruses could result from research led by The University of Queensland.

Associate Professor Daniel Watterson from UQ’s School of Chemistry and Molecular Biosciences said the team identified an antibody that improved survival rates in laboratory trials and reduced the presence of virus in the blood.

“We made a discovery in 2015 in the wake of the Zika outbreak that identified a new target for flavivirus treatments, a viral protein called NS1,” Dr Watterson said.

“Now we’ve shown for the first time that a single NS1 antibody can be protective against multiple flaviviruses including dengue, Zika and West Nile.

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The Antimalarial Compound Atovaquone Inhibits Zika and Dengue Virus Infection by Blocking E Protein-Mediated Membrane Fusion.

From Physicians Weekly
December 31, 2020

Flaviviruses bear class II fusion proteins as their envelope (E) proteins. Here, we describe the development of an in vitro quantitative mosquito-cell-based membrane-fusion assay for the E protein using dual split proteins (DSPs). The assay does not involve the use of live viruses and allows the analysis of a membrane-fusion step independent of other events in the viral lifecycle, such as endocytosis. The progress of membrane fusion can be monitored continuously by measuring the activities of luciferase derived from the reassociation of DSPs during cell fusion. We optimized the assay to screen an FDA-approved drug library for a potential membrane fusion inhibitor using the E protein of Zika virus. Screening results identified atovaquone, which was previously described as an antimalarial agent. Atovaquone potently blocked the in vitro Zika virus infection of mammalian cells with an IC of 2.1 µM. Furthermore, four distinct serotypes of dengue virus were also inhibited by atovaquone with IC values of 1.6-2.5 µM, which is a range below the average blood concentration of atovaquone after its oral administration in humans. These findings make atovaquone a likely candidate drug to treat illnesses caused by Zika as well as dengue viruses. Additionally, the DSP assay is useful to study the mechanism of membrane fusion in Flaviviruses.

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NIH grant funds development of novel biosensor technology for diagnosing viral infections

From the UC Santa Cruz News Center
December 16, 2020

For over ten years, Ali Yanik has been working to develop novel biosensor technology to provide rapid, low-cost testing for disease diagnostics and precision medicine. Now, with a five-year, $3.7 million grant from the National Institutes of Health, he and his collaborators are poised to complete the development and validation of a prototype and begin testing it in the field for detection of dengue fever, yellow fever, and Zika virus infections.

“We’re confident in being able to do this and get it into the field for testing,” said Yanik, an assistant professor of electrical and computer engineering in the Baskin School of Engineering at UC Santa Cruz. “It’s pretty revolutionary because this is a very simple tool, and yet it is also very sensitive.”

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New viral detection technique uses smartphone camera to diagnose various infections

From EurekAlert!
December 16, 2020

Scientists have developed a novel smartphone-based technique to diagnose viral infections that uses a deep learning algorithm to identify viruses in metal nanoparticle-labeled samples, enabling rapid virus detection without the need for skilled laboratory workers and expensive equipment. The system correctly identified clinically relevant concentrations of Zika, hepatitis B (HBV), or hepatitis C (HCV) in 134 patient samples with 98.97% sensitivity. Mobile phone subscribers are on the rise worldwide, including in sub-Saharan African populations that are heavily burdened by infection outbreaks. Since these widely available technologies also possess powerful new computing abilities and built-in sensors, scientists have identified mobile phones as a promising tool to help manage infectious diseases worldwide. 

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Persistence of Zika virus in the brain causes long-term problems in mice

From EurekAlert!
December 10, 2020

The Zika virus can remain in mouse brain for extended periods, leading to long-term neurological and behavioral consequences, according to a study published December 10 in the open-access journal PLOS Pathogens by Daniela Verthelyi of the US Food and Drug Administration, and colleagues.

Infections in the perinatal period are associated with lasting cognitive impairment and increased risk for psychological disorders. The congenital brain malformations associated with Zika virus infections early in pregnancy are well documented. But the potential defects and long-term consequences associated with milder infections in late pregnancy and the perinatal period are less well understood. To address this knowledge gap, Verthelyi and colleagues exposed one-day-old mice to the Zika virus and monitored the neurological and behavioral consequences up to one year later.

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$2 million NIH grant to develop Zika virus vaccine

From EurekAlert!
December 10, 2020

Flaviviruses — a group of viruses transmitted by ticks or mosquitoes — infect an estimated 400 million people annually with diseases like yellow fever, Dengue fever, West Nile virus, and, most recently, Zika virus.

Outbreaks of Zika virus, a flavivirus originating in Africa, were once rare and isolated events. But in 2015, it arrived in the Americas and rapidly spread to 27 countries within the span of a year.

Zika virus outbreaks have now been recorded throughout Southeast Asia, the South Pacific, South America, and Central America. To protect the health of billions of people at risk and prevent future outbreaks, a team of Virginia Tech researchers received a $2 million R01 grant from the National Institutes of Health to develop a safe, effective, single-dose vaccine candidate for Zika virus.

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People Previously Infected With Dengue Are Less Likely to Suffer From Zika Complications

From Gilmore Health News
December 6, 2020

A study of 3,000 children during an outbreak in Nicaragua showed that those previously infected with dengue were less likely to develop Zika symptoms. Both Zika and Dengue viruses are, transmitted by the same type of mosquitoes and cause similar symptoms.

The dengue virus has been present in the Americas for decades, while Zika did not appear in Brazil until 2015, before spreading rapidly. The dengue and Zika viruses are transmitted by the bite of the Aedes aegypti mosquito and cause similar symptoms to the flu: fever, muscle, and joint pain, etc. There may also be redness in the skin.

However, in pregnant women, a Zika infection can lead to serious disturbances in the development of the fetus, especially microcephaly. Neurological complications (Guillain-Barré syndrome) are also possible in infected women. However, Zika infection is often asymptomatic.

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Evolving malaria mosquitoes getting harder to control

From MedicalXpress
December 4, 2020

Anopheles malaria mosquitoes in Africa and Latin America are evolving in response to human activity, studies in both continents have found.

Anopheles gambiae, the most significant malaria vector in Africa, is developing increasing resistance to pyrethroid insecticides, a study published in Scientific Reports this month shows. Synthetic pyrethroids are the most commonly used insecticide for controlling  worldwide.

The team of researchers from Kenya, Ghana and the US say the indiscriminate use of pyrethroid insecticides in agriculture and public health programs could be responsible for the moderate and high-intensity resistance.

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Commonly used antibiotic shows promise for combating Zika infections

From the NIH
November 23, 2020

In 2015, hundreds of children were born with brain deformities resulting from a global outbreak of Zika virus infections. Recently, National Institutes of Health researchers used a variety of advanced drug screening techniques to test out more than 10,000 compounds in search of a cure. To their surprise, they found that the widely used antibiotic methacycline was effective at preventing brain infections and reducing neurological problems associated with the virus in mice. In addition, they found that drugs originally designed to combat Alzheimer’s disease and inflammation may also help fight infections.

“Around the world, the Zika outbreak produced devastating, long-term neurological problems for many children and their families. Although the infections are down, the threat remains,” said Avindra Nath, M.D., senior investigator at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and a senior author of the study published in PNAS(link is external). “We hope these promising results are a good first step to preparing the world for combating the next potential outbreak.”

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One Less Worry: Mosquitos Do Not Transmit COVID-19 – But They’re Still More Than Just Annoying

From Pasadena Now
November 23, 2020

he current surge in COVID-19 cases is renewing public anxiety about the virus, but experts say they want to put people’s minds at ease about one common concern: Mosquitos do not transmit COVID-19.

Since mosquitos are capable of transmitting other viruses, such as West Nile virus, Zika, dengue fever, yellow fever, and others, many concerned San Gabriel Valley residents have been posing the question, according to San Gabriel Valley Mosquito & Vector Control District spokesman Levy Sun.

Fortunately, all available research shows the annoying insects cannot transmit the virus between people they bite, he said.

“With the current surge in COVID-19 cases, also getting a renewed interest from the public regarding whether or not mosquitoes can transmit COVID-19. And so far, the evidence has been pointing to ‘no,’” Sun said.

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Fourth case of West Nile confirmed in Kern County this year

November 19, 2020

BAKERSFIELD, Calif. (KGET) — Health officials say they have diagnosed a fourth case of West Nile virus in Kern County.

California health officials announced the latest data Thursday showing 172 human cases of West Nile across the state. Twenty two counties in the state have reported human cases and seven people have died. There were no deaths from West Nile reported in Kern County.

Officials say more than 7,000 cases of West Nile and 300 deaths have been reported since 2003. And residents are urged to remove or drain any standing water where mosquitos that potentially carry the disease can breed.

West Nile is a disease spread by mosquitoes that most often spreads to people during the summer and early fall when the mosquitoes that carry the virus are most active.

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California Horse Confirmed With WNV

From The Horse
November 18, 2020

On Nov. 13, officials at the California Department of Food and Agriculture (CDFA) confirmed a horse in Sacramento County with West Nile virus (WNV). The affected horse, an undervaccinated yearling Thoroughbred colt, began showing clinical signs on Nov. 3. Signs consisted of ataxia (loss of control of bodily movements) and hind-limb neurologic signs. The colt is recovering.

According to CDFA, this is California’s 19th confirmed equine case of WNV in 2020. Other counties with confirmed cases include: Amador (2), Butte (1), Glenn (1), Kinds (1), Merced (1), Modoc (1), Nevada (1), Riverside (2), San Bernardino (1), San Joaquin (4), and Stanislaus (3).

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New App Identifies Mosquitoes by Buzzing Sound

From VOA News
November 16, 2020

The high-pitched whine of a mosquito is annoying, but scientists have developed an app that uses that sound to detect dangerous mosquitoes.

Mosquitoes kill hundreds of thousands of people each year by spreading microbes that cause diseases such as malaria, dengue fever and yellow fever. But researcher Haripriya Vaidehi Narayanan says anyone with a cellphone can help tackle these diseases by using the Abuzz app to identify mosquitoes. 

“If they see a mosquito around us, they just open the phone, open up the app, point their phone towards the mosquito and hit the record button,” said Narayanan, who started working on the project as a graduate student at Stanford University. She’s now in the Department of Immunology at the University of California Los Angeles. 

“So then, when the mosquito flaps its wings and starts flying around, it makes that noise, that annoying buzzing noise … that noise is what gets recorded by the Abuzz app,” she added. 

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O.C. residents urged to help fight new ankle-biting mosquito

From the Laguna Beach Independent
November 12, 2020

Laguna Beach residents are reporting an uptick in ravenous ankle-biting mosquitos following recent rainstorms, the Orange County Vector Control District shared this week.

It’s very possible the bites are attributable to a newcomer to Orange County—the Aedes mosquito. Laguna Woods and Laguna Hills residents had issues this summer with this species but OC Vector Control crews haven’t trapped one in Laguna Beach yet, agency spokesperson Heather Hyland said.

“Our district has not been able to collect and confirm an invasive Aedes sample, however, the calls we have received from Laguna Beach confirm that residents are reporting day time aggressive biting on lower legs is indicative of these mosquitoes,” she said.

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Wolbachia in mosquitoes from the Central Valley of California, USA

From Bio Med Central
November 10th, 2020


Wolbachia bacteria are widely distributed throughout terrestrial arthropod species. These bacteria can manipulate reproduction and influence the vector competence of their hosts. Recently, Wolbachia have been integrated into vector control programmes for mosquito management. A number of supergroups and strains exist for Wolbachia, and they have yet to be characterized for many mosquito species. In this study, we examined Wolbachia prevalence and their phylogenetic relationship to other Wolbachia, using mosquitoes collected in Merced County in the Central Valley of California.


Adult mosquitoes were collected from 85 sites in Merced County, California in 2017 and 2018. Traditional and quantitative PCR were used to investigate the presence or absence and the density of Wolbachia, using Wolbachia-specific 16S rRNA and Wolbachia-surface protein (wsp) genes. The supergroup of Wolbachia was determined, and Multilocus Sequence Typing (MLST) by sequencing five housekeeping genes (coxA, gatB, ftsZ, hcpA and fbpA) was also used to determine Wolbachia supergroup as well as strain.

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Combat The Bite In Coronado

From the Coronado Eagle Journal
November 9th, 2020

Recently, residents have noticed an increase in the number of mosquitoes in Coronado. There is a new invasive species of mosquito called the Aedes, that is spreading across California. The Aedes breeds in small areas of water and even some plants. The San Diego County Vector Control handles the inspection and treatment of mosquitoes in cities around the County. The City is working with County officials to treat storm drains, public parks and facilities to address mosquito concerns. Residents can do their part to “combat the bite” by eliminating standing water that can accumulate in pots, rain barrels, trashcans and outdoor toys and furniture. Vector control services are funded through a benefit assessment and are available to every property owner. Residents can contact the County directly to request property inspections and treatment, file complaints or ask questions. Residents and businesses can reach the County Vector Control Program at 858-694-2888 or at

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Mosquitoes in Santa Barbara Test Positive for West Nile Virus

From the Daily Nexus
November 8, 2020

These mosquitoes, commonly known as southern house mosquitoes, were discovered in traps for a different invasive species of mosquitoes Aedes aegypti discovered in early October. These traps were set up in a house in Santa Barbara near the intersection of North La Cumbre Road and Foothill Road. 

Brian J. Cabrera, general manager of the Mosquito and Vector Management District of Santa Barbara County, said that the mosquitoes likely picked up West Nile virus from infected birds, which they tend to feed on. According to Cabrera, carrier mosquitoes have the potential to pass the virus on to humans — but it isn’t a reason for panic. 

“It’s not an imminent threat, but we should remain vigilant,” Cabrera said. “The disease caused, or the illnesses caused by West Nile virus, only affects a small percentage of the people who actually acquire the virus from a mosquito bite.”

Cabrera said that 80% of people infected don’t feel symptoms at all. Those that do get sick, he said, will experience fever, headaches, rashes and nausea. According to the Centers for Disease Control and Prevention, about 1% of West Nile virus cases are fatal, with elderly and otherwise immunocompromised individuals particularly at risk. 

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Kern County reporting third human case of West Nile

From Bakersfield Now
November 6th, 2020

According to the State of California’s West Nile site, Kern County has had three confirmed human cases of West Nile so far this year.

West Nile virus is a disease that is spread by mosquitoes and most often spreads to people during the summer and early fall when the mosquitoes that carry WNV are most active.

While many mosquito-borne illnesses such as WNV cause only mild symptoms in most people, the infection can cause severe illness and even death in rare cases, according to public health.

Most people who contract WNV have symptoms that include fever, headache, body aches, joint pain, nausea, vomiting and sometimes a skin rash.

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Fighting Zika? Call in the T cells

From Medical Xpress
November 4, 2020

Where Aedes mosquitoes fly, Zika virus may not be far behind. Although the explosive 2015-2016 Zika epidemics in the Americas are behind us, Zika may re-emerge, and “in many countries, Zika may be spreading in silence,” says Sujan Shresta, Ph.D., a professor at La Jolla Institute for Immunology (LJI). “We need to develop effective vaccines.”

In a new Science Advances study, Shresta and her colleagues at LJI report that the immune system’s T  have the power to prevent Zika infection in mice. This finding suggests that effective Zika vaccines need to activate T cells to work alongside antibodies.

“If we combine T cells and antibodies, we have even stronger protection and longer-term protection,” says Annie Elong Ngono, Ph.D., a postdoctoral fellow at LJI and first author of the new study.

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UC researchers are pioneering a more effective way to block malaria…

From AlKhaleejToday
November 3, 2020

Using a strategy known as “population modification,” which involves using a CRISPR-Cas9 gene propulsion system to introduce genes that prevent parasite transmission into mosquito chromosomes, University of California researchers have made a great leap forward in the use of genetic technologies for the Control of the transmission of made malaria parasites.

Postdoctoral fellow Adriana Adolfi of the University of California at Irvine, working with colleagues from UCI, UC Berkeley and UC San Diego, pursued the group’s pioneering efforts to develop CRISPR-based gene drive systems to make mosquito vectors resistant to the transmission of malaria parasites Genetic drive in female mosquito offspring.

“This work alleviates a major problem with the early gene propulsion systems, namely the buildup of propulsion-resistant mosquitoes that can still transmit malaria parasites,” said UCI vector biologist Anthony James, Donald Bren Professor of Microbiology and Molecular Genetics and Molecular Biology & Biochemistry, who co -Primary Investigator was involved in the study.

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Exchanging potted plants is spreading mosquito population

From Winters Express
October 29, 2020

The Sacramento-Yolo Mosquito and Vector Control District discourages the practice of exchanging potted plants as the invasive mosquito population in Winters remains widespread across town.

In mid-September an adult female Aedes aegypti mosquito was found in a trap placed near East and Main streets. The invasive container-breeding mosquito is an aggressive species that prefers to bite people during the day and has the potential to transmit serious diseases including Zika, dengue and chikungunya. The discovery in Winters was the first of its kind detected in Yolo County, ever. It has since been found in other communities including the neighboring City of Davis.

Winters continues to host the largest infestation in Yolo County.

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Invasive mosquito that can spread several diseases found in Oroville

October 28, 2020

An invasive mosquito that can spread several diseases has been found in Oroville.

The non-native species, known as the Yellow Fever Mosquito, can transmit viruses such as Zika, Dengue, and Yellow Fever as the name suggests.

Mosquitos that are native to the area don’t spread those diseases, county officials say.

There is now a rush to eradicate the invasive species and contain it to the area of Oroville Dam Boulevard and Feather River Boulevard.

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Mosquitoes Caught in Santa Barbara Test Positive for West Nile Virus

From Noozhawk
October 28, 2020

A sample of mosquitoes collected from a mosquito trap in Santa Barbara has tested positive for West Nile Virus (WNV), according to the Mosquito & Vector Management District of Santa Barbara County.

The mosquitoes were trapped as part of ongoing surveillance for the recently discovered invasive Aedes aegypti mosquitoes that were discovered earlier this month.

“This is not the first time West Nile virus has been found in Santa Barbara County, but it has been three years since it was last detected,” said Brian Cabrera, district general manager.

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Mosquitos captured in Santa Barbara test positive for West Nile

October 27, 2020

SANTA BARBARA, Calif. — Mosquitos that were caught in Santa Barbara tested positive for West Nile Virus on Tuesday.

The Mosquito & Vector Management District of Santa Barbara County caught a sample of mosquitoes from a mosquito trap and tested them after the invasive Aedes aegypti mosquitoes were discovered earlier this month.

The sample of mosquitoes that were caught tested positive for the West Nile Virus.

“This is not the first time West Nile virus has been found in Santa Barbara County,” says District General Manager Brian Cabrera, “but it has been three years since it was last detected.”

Officials say humans can contract the West Nile Virus after getting bitten by an infected mosquito.

Officials warn that most people who contract the virus don’t know they are infected and don’t develop any symptoms.

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Meet the Man Fighting an Ankle-Biting Mosquito Invasion with Fish

From Spectrum News 1
October 26, 2020

GARDEN GROVE, Calif. — Every morning Michael Saba heads out to feed his fish — all 75,000 of them.

Known as “The King Fish,” Saba is a marine biologist with the Orange County Mosquito and Vector Control District, where he rules over an army of tiny silvery creatures.

“I think they’re the most beautiful organisms on the planet,” he said.

His fish are not all that different than the kind you’d buy at a pet store — except for one thing.

“This is one of that family of fishes that just happens to eat mosquito larvae in abundance when it’s present,” he said.

Called mosquitofish, they’re nature’s best weapon against pesky blood suckers. Once they reach adulthood, the fish are delivered to backyard fountains and ponds all over Orange County, where they’ll gobble up little mosquito larvae.

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Officials find first ‘murder hornet’ nest in the US

From KCRA 3
October 23, 2020

They’re here, and they’re apparently making themselves at home.

The Washington State Department of Agriculture on Friday confirmed they located the first Asian giant hornet nest in the U.S.


The nest was inside a hole in a tree located on “private property near an area cleared for a residential home,” WSDA said in a news release.

WSDA said its team saw dozens of the so-called “murder hornets” exiting and entering the tree.

The department spent weeks trapping the giant hornets and have been actively searching for them since the first hornets were caught earlier this year. The hornets were first detected in Washington in December the first one was trapped in July.

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Dangerous Mosquito Species Spreading Throughout Northern California

From CBS Sacramento
October 23, 2020

ARDEN-ARCADE (CBS13) — A pandemic, a historic fire season and now disease-carrying mosquitoes that can spread the Zika virus. Mosquitos are becoming more than just a nuisance in the Arden-Arcade area.

In the last two weeks, Martie Nolan has discovered at least 14 bites that have left a mark.

“I started getting bites all over my legs just by going outside to take the trash out,” said Nolan. “I still get a little scared cause you never know.”

Nolan’s family is one of the dozens in her Arden-Arcade neighborhood that Sacramento-Yolo mosquito and vector control has visited to warn about an invasive mosquito in the area that is capable of carrying Zika and other dangerous diseases.

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Dangerous Mosquito Species Spreading Throughout Northern California

From CBS Sacramento
October 23, 2020

ARDEN-ARCADE (CBS13) — A pandemic, a historic fire season and now disease-carrying mosquitoes that can spread the Zika virus. Mosquitos are becoming more than just a nuisance in the Arden-Arcade area.

In the last two weeks, Martie Nolan has discovered at least 14 bites that have left a mark.

“I started getting bites all over my legs just by going outside to take the trash out,” said Nolan. “I still get a little scared cause you never know.”

Nolan’s family is one of the dozens in her Arden-Arcade neighborhood that Sacramento-Yolo mosquito and vector control has visited to warn about an invasive mosquito in the area that is capable of carrying Zika and other dangerous diseases.

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Aedes Aegypti Mosquito Found In Moorpark, Ventura County

From the Moorpark, CA Patch
October 22, 2020

The City of Moorpark Vector Control Division (Division) has detected Aedes aegypti mosquitoes within the City of Moorpark. The first detection was on October 13, 2020 at a residence in downtown Moorpark within a few blocks of Moorpark Avenue. This Division is working with the Ventura County Environmental Health Division and the California Department of Public Health to evaluate the extent of the infestation and will aggressively target problem areas to prevent its spread.

Aedes aegypti is not native to Ventura County. It is a small, aggressive day-biting mosquito that is now widespread in many California communities. While native mosquitoes typically bite at sundown or night, Aedes aegypti is most active during daylight, for approximately two hours after sunrise and several hours before sunset. This mosquito is capable of transmitting several viruses, including dengue, Chikungunya, yellow fever, and Zika. While these viruses are not currently transmitted in California, the importance of avoiding mosquito bites remains the same, just as they are with native species that carry West Nile virus.

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San Joaquin County reports first human case of uncommon mosquito-borne virus in nearly 40 years

From ABC 10
October 22, 2020

STOCKTON, Calif. — San Joaquin County Public Health Services (SJCPH) said it has received the first reported human case of the mosquito-borne disease St. Louis encephalitis virus (SLEV) in the county in nearly 40 years. 

The health agency said that in August, the district’s mosquito-borne disease surveillance program discovered SLEV in a group of collected mosquitoes in roughly the Lodi/Lockeford area. It was the first environmental detection of SLEV in the county since 1973.

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Mosquito that can carry Zika virus turns up near Isleton, vector district officials say

From the Sacramento Bee
October 22, 2020

The mosquito that can carry the Zika virus has been spotted this week in yet another area of Sacramento County, this time in Isleton, according to a report Thursday from the Sacramento-Yolo Mosquito and Vector Control District.

The invasive Aedes aegypti bite during the day and lay eggs just above the water line in containers that hold relatively little water such as pet dishes, bird baths and the saucers beneath flower pots.

Locally, vector district officials also have reported detecting them in Arden Arcade and Winters.

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Artificial Light May Make Aedes Aegypti Mosquitoes ‘Abnormally’ Active At Night, Study Shows

From the International Business Times
October 21, 2020

Aedes aegypti mosquitoes, which are carriers of dengue and Zika viruses, are known to be active biters during the daytime, but a team of researchers has found that artificial lights can “abnormally” increase their biting behavior even at night.

Aedes Aegypti mosquitoes transmit various mosquito-borne diseases such as dengue fever, chikungunya, yellow fever and Zika fever. The species mostly bite in the early morning and in the afternoon hours when there is light, but what happens when they are exposed to artificial lights at night?

To find out, a team of researchers conducted an experiment wherein the study’s first author, Samuel S. C. Rund of the University of Notre Dame’s Department of Biological Sciences, let mosquitoes bite him under certain conditions including during daytime, at night, and at nighttime while exposed to artificial light. They then measured the mosquitoes’ blood-feeding behavior.

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Kern County reports first 2020 West Nile Virus case

From the Kern Valley Sun
October 14, 2020

In an Oct. 6 news release, Kern County Public Health Services said it has received confirmation of a human case of West Nile Virus (WNV), the first reported case in the county for 2020.

West Nile Virus is a mosquito-borne disease that normally spreads during the summer and early fall months. While it is not fatal to most people, it can pose a serious risk in certain individuals, leading to death in the rarest of cases. Approximately 20% of infected persons will experience symptoms such as headaches, fevers, joint pain, body aches, nausea and possibly skin rashes.

Less than 1% of people experience severe symptoms in which the virus affects the brain and nervous system. These symptoms can include confusion, neck stiffness and high fever. The Department of Public Health Services urges individuals experiencing symptoms related to the virus, especially after being bitten by a mosquito, to contact a medical care professional for further information.

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West Nile virus symptoms are similar to COVID-19 at first, experts say

October 12, 2020

According to the CDC, more than 30 states are reporting West Nile virus infections in people, birds or mosquitoes. Early symptoms of West Nile are similar to any virus or the common cold. These days, that means it’s hard to differentiate from COVID-19.

In Los Angeles, it’s a big job to mitigate mosquitoes. The Greater LA County Vector Control District serves nearly 6 million people in 35 cities. So far this year, more than 230 mosquitoes have tested positive for West Nile.

“Every year, our mosquito season seems to get longer and longer and that goes into it being warmer and warmer,” said Anais Medina Diaz, the public information officer for the LA County Vector Control District. “Now we’re seeing mosquito season go from March to the end of October, sometimes into the beginning of November.”

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More mosquitoes test positive for West Nile virus in LA County

From the Antelope Valley Press
October 12, 2020

LOS ANGELES — Twenty-six more mosquito samples tested positive for West Nile virus this week in Los Angeles County, bringing to 264 the number of positive samples so far this year, vector control officials reported Friday.

The mosquito samples all were collected from areas previously identified as positive for the virus, according to the Greater Los Angeles County Vector Control District. The highest totals of mosquitoes that have tested positive this year were reported in: Encino and North Hollywood with 14 each, Valley Village with 13, Van Nuys and Pico Rivera with 12 each and Studio City and Toluca Lake with 10 each.

West Nile virus is endemic in Los Angeles County, and warm temperatures can increase virus activity and mosquito populations, according to the GLACVC. As of Oct. 2, 93 West Nile human cases have been reported in California this year, 27 of which were identified by the Los Angeles County Department of Public Health.

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More Mosquitoes Test Positive for West Nile Virus in L.A. County

From NBC Los Angeles
October 9, 2020

Twenty-six more mosquito samples tested positive for West Nile virus this week in Los Angeles County, bringing to 264 the number of positive samples so far this year, vector control officials reported Friday.

The mosquito samples all were collected from areas previously identified as positive for WNV, according to the Greater Los Angeles County Vector Control District. The highest totals of mosquitoes that have tested positive this year were reported in: Encino and North Hollywood with 14 each, Valley Village with 13, Van Nuys and Pico Rivera with 12 each and Studio City and Toluca Lake with 10 each.

West Nile virus is endemic in Los Angeles County, and warm temperatures can increase virus activity and mosquito populations, according to the GLACVC. As of Oct. 2, 93 WNV human cases have been reported in California this year, 27 of which were identified by the Los Angeles County Department of Public Health.

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West Nile Virus claims lives of two people in Merced County, abatement district says

From the Merced Sun-Star
October 8, 2020

West Nile Virus has led to the deaths of two individuals over age 50, a Merced County Mosquito Abatement District news release reported.

Each person had underlying health conditions prior to their death.

Although the fatalities were reported on Thursday, both occurred during September, the release said.

As of Oct. 2, a total of 93 known West Nile Virus cases have been reported in California this year. Four deaths have been traced to the virus, meaning half of fatalities statewide are Merced County residents.

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There are more mosquitoes in Tulare County, but not as many carrying disease

October 8, 2020

VISALIA, California (KSEE) — October is usually when the number of mosquitoes declines – but in some parts of Tulare County the number is going up.

While the number of diseased mosquitoes is down from last year, mosquito-transmitted diseases like West Nile virus are still being found in humans.

Inside the lab at the Delta Vector Control District, one water sample contains an abundant amount of larvae. Petri dishes also line the counters, filled with hundreds of mosquitoes caught in traps.

General Manager Dr. Mustapha Debboun said the Central Valley’s prolonged heat has made ideal mosquito breeding conditions.

Recently, there’s been an uptick in neighborhoods in northwest Visalia. The district conducted targeted treatment in some of them Thursday morning. However, the number of mosquitoes found carrying viruses is down from 2019. So far, only 139 mosquitoes have been found with West Nile virus, while 39 have been found with St. Louis Encephalitis virus.

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Sacramento officials find mosquitoes that can carry Zika virus near Arden Arcade park

From the Sacramento Bee
October 7, 2020

Even as the Sacramento Valley cools down, the yellow fever mosquito is being discovered in traps in new areas. Some were found this week near Cresta Park in the Arden Arcade area, the Sacramento-Yolo Mosquito and Vector Control District announced Wednesday.

This aggressive day-biting pest, more formally known as Aedis aegypti, can carry not only yellow fever, but also Zika virus, dengue and chikungunya. While mosquitoes breed more quickly during the heat of summer, these new reports show local residents shouldn’t let down their guard this autumn.

“Your assistance is critical! If you are being bitten throughout the day or notice more mosquitoes in your yard, please give the district a call to request a free inspection,” said Gary Goodman, the district manager, in a news release.

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Mosquito tests show no further signs of West Nile virus

From the Half Moon Bay Review
October 7, 2020

Mosquito tests for West Nile virus done last week came back negative on Thursday, after a dead American crow in South San Francisco was found to have the virus.

The bird signaled the first indication of West Nile virus in San Mateo County since 2018, according to a statement by the San Mateo County Mosquito and Vector Control District.

Following the report, the district deployed mosquito traps in the neighborhood where the dead bird was collected.

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More mosquitoes, one human test positive for West Nile Virus in Valley

From the Antelope Valley Press
October 7, 2020

LANCASTER — More mosquitoes collected from mosquito traps in Palmdale have tested positive for West Nile virus (WNV). 

One trap was located near 25th Street West and Avenue P-8. The other trap was located near 30th Street East and Avenue R. To date, there have been 13 West Nile positive mosquito samples for the 2020 mosquito season. 

Public Health also reported another human case of West Nile virus within District boundaries, which brings the local human West Nile virus count to seven cases.

The District would like to reinforce the importance of keeping the mosquito population low. The lower the mosquito abundance, the less opportunity there is to have an issue with mosquito-borne disease transmission. Brenna Bates-Grubb, community outreach specialist for the AVMVCD said that “There is no vaccine or cure for West Nile virus, so the best way to stay safe is through prevention of mosquito bites. Prevent mosquitoes from breeding around your home by eliminating sources of standing water at least weekly and wear mosquito repellent when outdoors.”

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From Edhat Santa Barbara
October 3, 2020

Source: Mosquito and Vector Management District of Santa Barbara County

The Mosquito and Vector Management District of Santa Barbara County has confirmed the presence of the non-native Aedes aegypti mosquito in Santa Barbara County. Photos of a suspect mosquito caught at a home in the Hope neighborhood in Santa Barbara were submitted to the District’s website by an alert resident.  The suspect mosquito specimens were collected from the residence located near the intersection of N. La Cumbre Rd. and Foothill Rd. and tentatively identified as Aedes aegypti at the District laboratory. An additional specimen was collected from a trap set up at the residence where the mosquitoes were found and it was positively identified as Aedes aegypti, the yellow fever mosquito. Mosquito district staff currently are setting up additional traps, conducting property inspections, and passing out informational brochures in the surrounding neighborhood. 

Aedes aegypti is native to Africa but has spread throughout many regions of the world. This mosquito was first detected in California in 2013 and since then has spread throughout southern California and the Central Valley. Aedes aegypti can transmit viruses such as Dengue, Zika and Chikungunya and the virus that causes yellow fever but, fortunately, these diseases are not locally transmitted in California. However, this mosquito can be extremely bothersome, biting both during the day and at night and can be found both indoors and outdoors. Residents in areas where the mosquito has become well established call them “ankle biters” due to their habit of biting around the ankles. Aedes aegypti prefer feeding on humans and stay close to human dwellings where they will lay their eggs in practically anything that contains stagnant water including buckets, tires, birdbaths, containers of all kinds, and plates under potted plants. They can even develop in water held in plants, such as bromeliads. Aedes aegypti mosquito larvae can complete their development in the amount of water that would fill a bottle cap. Residents are urged to remove all sources of stagnant water both inside and outside of the home and scrub the sides of the containers because the eggs can survive without water for many months.

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OC Cities Battle Explosion Of Non-Native ‘Ankle-Biter’ Aedes Mosquitoes

From CBS Los Angeles
October 2, 2020

SANTA ANA (CBSLA) – Amid an explosion of non-native “ankle-biter” Aedes mosquitos across the Southland this summer and fall, Orange County is trying out a new treatment to combat the insects.

The O.C. Mosquito and Vector Control District Thursday was using an A1 Super Duty larvicide sprayer to spray out a mist with an organic bacteria at Fairhaven Cemetery in Santa Ana.

“What we are doing tonight is a wide area larvicide spraying,” Heather Hyland with OCMVC told CBSLA Thursday.

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West Nile Virus cases reported in Tulare County

From FOX 26 News
October 1, 2020

The Tulare County Health & Human Services Agency announced five human cases of West Nile Virus have been reported in Tulare County.

Two cases are confirmed to have contracted the virus and three cases are probable.

Public health officials urge residents to take precautions against mosquito bites, as mosquito samples positive for West Nile Virus have been detected in multiple locations within the county.

In addition, samples indicate that St. Louis Encephalitis Virus (SLEV) may also be present, posing a risk to the public.

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Aedes aegypti mosquitoes found across Ventura County. Here’s what we know.

From the Ventura County Star
October 1, 2020

After emerging for the first time in Ventura County less than a month ago, potentially dangerous Aedes aegypti mosquitoes have now been found in east and west Ventura, Fillmore, Westlake Village, Piru, Thousand Oaks and Simi Valley, officials said Thursday.

Unconfirmed reports of the mosquito have also come from other communities, including Camarillo and Santa Paula.

“We expect to get more reports from all areas of the county,” said Cary Svoboda, program lead for Ventura County Environmental Health Division’s vector control program. “They’re just very good at moving around and getting their foot in the door.”

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County detects West Nile virus in dead bird for first time this year

From The Almanac
September 30, 2020

San Mateo County’s Mosquito and Vector Control District has detected West Nile virus in a dead bird for the first time this year.

The bird — an American crow — was collected in South San Francisco earlier this week, the vector control district said Wednesday.

It is the first case of the virus found in San Mateo County since 2018. Though reports of dead birds indicate presence of the virus, the risk to humans remains low.

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Zika-carrying mosquito species found in Davis

From FOX 40
September 30, 2020

DAVIS, Calif. (KTXL) — The mosquito responsible for the spread of the Zika virus has broken out of a containment zone in Winters and has been found in a neighborhood in Davis.

The Sacramento-Yolo Mosquito and Vector Control District aggressively went after the Aedes aegypti mosquito in 2019, an invasive insect that’s known to carry the Zika virus and several other exotic diseases.

The discovery of the mosquito in Sacramento County was the first time the insect had appeared this far north.

In 2016, a Zika outbreak in the United States caused bitten pregnant women to have an increased risk of their babies being born with deformities and permanent neurological damage.

In mid-August, a major infestation in the Yolo County town of Winters drew lots of attention from mosquito technicians.

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Adult Mosquito Control to take place in Discovery Bay

From The Press
September 30, 2020

Due to the high abundance of mosquitoes in the area, the Contra Costa Mosquito & Vector Control District will be using truck-mounted ultra-low volume sprayers to control adult mosquitoes.

DATE: Thursday, October 1, 2020

TIME: Between dusk (approximately 7:00 p.m.) and 11:00 p.m., weather permitting.

LOCATION: Discovery Bay

The area to be treated is bordered on the north by Willow Lake Road and Marina Road; on the south by Wayfarer Court and Cherry Hills Drive; on the east by Channel Drive; and on the west by Discovery Bay Boulevard.

MATERIALS USED: The insecticide to be used is Zenivex E4 RTU applied at a rate of 1.5 ounces per acre by truck-mounted ultra-low volume sprayers.

MAP: For an interactive map, please click here.

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Pandemic Could Make SoCal’s Mosquito Invasion Even Worse

From NBC Los Angeles
September 30, 2020

Millions of Southern Californians have been under attack–itching and scratching from bites all over their bodies–by what appears to be a record explosion of tiny “ankle-biter” mosquitoes, known as the Aedes breed.

“I have bites on my ears, under my chin, on my breasts, in between my fingers, not just on my ankles,” says LA resident Rosemary Hochschild. “I feel like I’m going to go mad.”

But efforts to control these mosquitoes by LA County’s Vector Control agency have been hampered by the pandemic.

When the pandemic started, Vector Control had to stop performing service calls at residents’ homes. During those calls, Vector Control inspectors will come to your home, tell you where mosquitoes are breeding, and often treat those areas with “larvicide.”

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