First case of human West Nile virus confirmed in Kern County

From Bakersfield Now
August 23, 2019

Kern County confirmed Friday morning its first human case of West Nile virus this year.

According to the California West Nile Virus website, there were 31 new human cases reported this week in the state.

This brings the total to 45 human cases in 11 counties within the state.

Two people have died in connection to the disease including one person in Fresno County.

Most often, West Nile virus is spread by the bite of an infected mosquito.

Mosquitoes are carriers (“vectors”) that become infected when they feed on infected birds. Infected mosquitoes can then spread the virus to humans and other animals when they bite.

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First West Nile Virus death reported in Fresno County this year

From ABC 30
August 22, 2019

FRESNO, Calif. (KFSN) — The Fresno County Department of Public Health has confirmed the first West Nile Virus death in the county this year.

Health officials say another person also tested positive for Saint Louis Encephalitis which is the first reported case in Fresno County.

According to county officials, as of Wednesday, there are 26 positive human cases of West Nile this year, and that number is expected to increase.

At this time, FCDPH is collaborating with Fresno County mosquito abatement districts and the Central California Blood Center to increase awareness about mosquito activity.

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Zika Was Soaring Across Cuba. Few Outside the Country Knew.

From the New York Times
August 22, 2019

A previously unknown outbreak of the Zika virus swept across Cuba in 2017, a year after the global health emergency was declared over, scientists reported on Thursday.

Until now, the Pan American Health Organization had no record of any Zika infection in Cuba in 2017, much less an outbreak. Following inquiries by The New York Times about the new study, published in the journal Cell, officials acknowledged that they had failed to tally 1,384 cases reported by Cuban officials that year.

That figure is a sharp increase over the 187 cases confirmed in 2016 and is “in line with the estimates for 2017 from our own study,” said Kristian Andersen, an infectious disease researcher at Scripps Research Translational Institute in La Jolla, Calif., and a co-author of the new study.

Because most cases of Zika go unconfirmed, Dr. Andersen added, the outbreak actually may have comprised tens of thousands of infections.

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County confirms three more cases of mosquito-borne illness

From the Imperial Valley Press
August 22, 2019

EL CENTRO — Confirmation three weeks ago that mosquitos carrying West Nile virus and Saint Louis encephalitis were found in the county was followed Wednesday with a report from the Imperial County Department of Public Health of two cases of SLE and the county’s second case of WNV this year.

The two cases of SLE are the first human cases of the disease reported statewide this year, the Health Department said. The West Nile case, unlike a case that killed a 74-year-old Bombay Beach resident on July 4, was not fatal.

The department said all three patients live in El Centro, and they are home recuperating.

The two SLE patients were reported to be middle-aged men who were hospitalized in late July with severe headache, fever and nausea, and were diagnosed with viral meningitis, the Health Department said. Fewer details were released about the West Nile case, other than the patient was also male.

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Mosquitoes in Davis test positive for West Nile virus

From the Davis Enterprise
August 22, 2019

West Nile virus has been detected in multiple mosquito samples tested in Davis in the last two weeks.

Those positive samples were found in north, east and south Davis between Aug. 6 and Aug. 20, according to the Sacramento-Yolo Mosquito & Vector Control District.

These are the first positive mosquito samples found in Davis this year, and come two weeks after the district reported the first positive samples in the county, in Winters and Zamora.

Davis locations where West Nile was detected in mosquitoes include Wildhorse near Duchamp Park; near Northstar Park in North Davis; and near Walnut Park in South Davis, according to the city and vector control district.

In response to this week’s findings, the city said ground spraying will continue in parks and open areas as needed in order to reduce mosquito populations and the vector control district will continue to monitor and conduct laboratory surveillance.

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From First Post
August 20, 2019

A deadly beast that might be the size of a speck but poses a threat to more than half the world’s population. This predator, your not so friendly neighbour, is the mosquito that causes so much menace around the world. They are the cause for the spread of many vector-borne diseases such as Dengue, Malaria, Yellow Fever, Chikungunya, Zika, and many more and have caused great losses to humanity.

Even with the progress of science and technology that has taken place, mosquitoes take almost 2.7 million lives every year. In the last 30 years, the worldwide incidence of dengue has risen 30-fold. Additionally, more countries have recently reported the outbreaks of Dengue. While the incidence of diseases caused by Aedes aegyptus mosquito continues to rise; the worldwide cases of Malaria has finally reached a stagnation point with just a slight increase in the last 3 years.

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County Finds More Mosquitos Infected with West Nile Virus

From SCV News
August 19, 2019

The Greater Los Angeles County Vector Control District has confirmed West Nile virus in four additional mosquito samples from traps in the cities of Carson, Northridge, Reseda and Signal Hill.

This follows the discovery of WNV-infected mosquito samples in Bellflower and Long Beach on July 15 and July 10, respectively.

The first two cases of WNV infections in humans were reported Aug. 5.

Residents are urged to use EPA-registered repellents when spending time outdoors to prevent mosquito bites and WNV illness. Not all repellents are effective against mosquitoes but the Centers for Disease Control and Prevention recommends repellents with the following active ingredients: DEET, Picaridin, IR3535 and Oil of Lemon Eucalyptus.

West Nile virus is endemic in Los Angeles County, and the summer heat can increase virus activity and mosquito populations. So far this year, 10 WNV human cases have been reported in California, two of which were identified by the Los Angeles County Department of Public Health. Visit CalSurv Maps for a comprehensive look at this year’s West Nile virus activity throughout Southern California.

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Mosquitos test positive for West Nile virus in Signal Hill, health officials say

From the Long Beach Post News
August 19, 2019

West Nile virus continues to be detected in mosquitos across Los Angeles County, recently showing up in Signal Hill, the Greater Los Angeles County Vector Control District reported today.

West Nile has already been detected this year in Long Beach and Bellflower. Today, the district said signs of the virus have been found in four additional mosquito samples from traps in Carson, Northridge, Reseda and Signal Hill.

Residents are urged to use EPA-registered repellents when spending time outdoors to prevent mosquito bites and West-Nile-related illness.

Not all repellents are effective against mosquitoes but the Centers for Disease Control and Prevention recommends repellents with the following active ingredients: DEET, Picaridin, IR3535 and Oil of Lemon Eucalyptus.

West Nile virus is endemic in Los Angeles County, and the summer heat can increase virus activity and mosquito populations, according to a district statement.

So far this year, 10 human cases of West Nile have been reported in California, two of which were identified by the Los Angeles County Department of Public Health.

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Tustin woman is 1st human case of West Nile virus in Orange County in 2019

From The Orange County Register
August 19, 2019

A female resident of Tustin, in her 50s, is the first human case of West Nile virus reported in Orange County this year, the Orange County Health Care Agency announced Monday, Aug. 19.

Last year, the virus affected 12 people in the county and resulted in one death, according to the Health Care Agency. The first human case reported in 2018 also was a Tustin woman.

On Aug. 5, the Orange County Mosquito and Vector Control District announced that mosquitoes found in Orange, along with nine dead birds discovered in Cypress, Buena Park, Huntington Beach and Tustin, had tested positive for the virus.

Last week, vector control officials said infected mosquitoes also had been found in Buena Park and Santa Ana.

The disease is passed on to humans by infected mosquitoes that contract it from birds.

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Mosquitoes carrying the West Nile Virus are spotted all over the Central Valley​

From the Debate Report
August 18, 2019

Officials of Fresno County in California have announced and warned the locals that mosquitoes infected with the West Nile Virus keep appearing in the Central Valley. Mosquito control districts have increased their attempts to control and exterminate the threat.

The Consolidated Mosquito Abatement Control District has begun making use of spray trucks geared with insecticide to spray the targeted areas all around the valley. The Culex species of mosquito is well-known to carry the West Nile Virus, and it is usually active in the evening and over the course of the night. The officials set for the trucks to spray during that specific time.

As per a collaboration between the California Department of Public Health, UC Davis and the Mosquito and Vector Control Association of California, there have been 319 mosquito samples that were found to be positive for the West Nile Virus in Fresno County thus far this year. The neighboring county, Tulare, has been even worse, having 613 positive tests for the virus until now.

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One-third of toddlers exposed to Zika in the womb suffer developmental problems, study says

From the Daily Herald
August 17, 2019

A new study of toddlers exposed to the Zika virus during their mothers’ pregnancies found that nearly a third suffered developmental delays and other problems — even if they were born without the abnormally small heads and underdeveloped brains often associated with the virus.

The study of more than 200 babies, published recently in the journal Nature Medicine, also shows that a very small number of children born with the congenital condition known as microcephaly had their symptoms improve. Conversely, a very small number of the children born without symptoms of microcephaly went on to develop it.

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West Nile virus now detected in La Verne and Pomona

From the Daily Bulletin
August 15, 2019

West Nile virus activity was detected in a sample of mosquitoes in La Verne and Pomona, the San Gabriel Valley Mosquito and Vector Control District announced Thursday.

The announcement comes 10 days after the announcement of a similar finding in Baldwin Park and Orange.

The vector control district tests female mosquitoes and birds throughout the year for the presence of the virus and other mosquito-borne diseases.

The West Nile virus is the most common mosquito-borne disease that affects Los Angeles County, according to the vector control district website.

Two people were reported to have contracted the virus in late July and are expected to recover, Los Angeles County Public Health officials announced Aug. 5.

Those who contract the virus may experience symptoms such as fever, nausea, mild rashes and body aches. Some may experience more severe neurological symptoms as a result of inflammation in the brain and spinal cord, leading to paralysis, coma or death, according to the vector control district website.

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Mosquitoes drive students indoors

From The Press
August 15, 2019

Last week, the Town of Discovery Bay was swarmed by a scourge of mosquitoes.

Likely hatched in nearby flooded fields, the inland floodwater mosquitoes caused enough trouble to trigger comments on social media pages and forced students at Old River Elementary (ORE) to spend their lunch and recess inside on Wednesday and Thursday.

“The kids (were) getting bit like crazy over here,” said ORE principal Ray Witte. “The kids are having a little bit more reaction to the bites, so we just said we are keeping them inside so they don’t get bit.”

Witte explained that his instructions came from the Knightsen district office, which was in contact with the Contra Costa Mosquito and Vector Control District (CCMVCD).

Nola Woods, public affairs director for CCMVCD said the insects are different than the average bloodsuckers that torment East County, but not dangerous.

“This is a mosquito that is an aggressive biter and it will bite during the day and at dusk,” Woods said. “The key thing about this mosquito is that it is not a known vector of West Nile Virus.”

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Birth defects associated with Zika virus infection may depend on mother’s immune response

From Science Daily
August 14, 2019

New research led by scientists at The Rockefeller University in New York may help explain why Zika virus infection causes birth defects in some children but not others. The study, which will be published August 14 in the Journal of Experimental Medicine, suggests that the risk of developing an abnormally small head (microcephaly) depends on the types of antibody produced by pregnant mothers in response to Zika infection.

The Zika virus is spread by mosquitoes in tropical and subtropical regions, and, in most adults, the symptoms of infection are fairly mild. But the widespread Zika outbreak in Brazil in 2015-2016 revealed that infection during pregnancy can cause a wide range of fetal abnormalities, with microcephaly occurring in around 5% of live births by Zika-infected mothers. “Why some Zika virus-infected pregnant women deliver apparently healthy newborns while others have babies with microcephaly is unknown,” says Davide F. Robbiani, a Research Associate Professor at The Rockefeller University, who co-led the study with Professor Michel C. Nussenzweig.

Various factors have been proposed to increase the risk of microcephaly, including previous exposure to viruses that are similar to Zika, such as dengue virus or West Nile virus. Antibodies generated by the body’s immune system to combat these viruses may recognize the Zika virus but, instead of neutralizing it, help it to enter the mother’s cells and possibly cross the placenta to infect the unborn fetus.

With the help of researchers and physicians in Brazil, Robbiani and colleagues analyzed blood samples collected during the 2015-2016 outbreak from Zika-infected mothers who had given birth to either healthy or microcephalic children.

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From Action News Now
August 13, 2019

BUTTE COUNTY, Calif. – The Butte County Public Health Department has announced the first confirmed human West Nile Virus infection in Butte County.

The infected person is an adult who suffered a fever-like illness.

As of Aug. 9, 2019, 10 human West Nile virus infections have been reported in California, not including the Butte County case. 

The infection is active July through October, with August typically being the peak month in Butte County. 

Health officials want to remind residents of the following tips to avoid contracting the virus:

  • Avoid spending time outside when mosquitoes are active, especially at dusk and dawn
  • If you must be outdoors when mosquitoes are active, wear long pants, and long-sleeved shirts, socks and shoes
  • Before going outdoors, apply insect repellent containing DEET, Picaridin, IR3535 or oil of lemon eucalyptus according to label instructions
  • Make sure that doors and windows have tight-fitting screens. Repair or replace screens that have tears or holes
  • Eliminate all standing water on your property that can support mosquito-breeding
  • Report standing water to Butte County Mosquito and Vector Control District
  • Contact Butte County Mosquito and Vector Control District if there is a significant mosquito problem where you live, work, and/or play

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Mosquitoes that can carry Zika virus caught in SJ County trap

From the Manteca Bulletin
August 13, 2019

The Aedes aegypti mosquito – also known as the mosquito that can carry the Zika virus and other communicable diseases – has officially arrived in San Joaquin County. 

On Monday the San Joaquin County Mosquito and Vector Control District announced that the invasive species, which was detected in neighboring Stanislaus County last month, was discovered in traps that were set last week just outside of the Stockton gated community of Brookside – prompting a response that includes extensive inspections of the area. 

“Our first goal is to control and limit the presence of this invasive mosquito species,” said Ed Lucchesi, the district’s manager. “We are doing everything possible now to ensure these mosquitoes do not become established in our communities; however, this type of mosquito can be very difficult to eliminate.”

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Health officials investigating 4 suspected human cases of West Nile Virus in Tulare County

From ABC 30
August 9, 2019

TULARE COUNTY, Calif. (KFSN) — Tulare County health officials are investigating four cases of suspected West Nile Virus in residents.

They believe three adults and one child have been affected.

Three are from the Visalia area, and one is from Tulare.

It comes as officials confirmed the Saint Louis Encephalitis Virus, also known as SLEV, has been detected in mosquitoes in Tulare County.

Symptoms of SLEV infection are similar to that of West Nile.

Mosquitoes transmit both illnesses.

Most people don’t even know they’re infected and show no signs of symptoms.

But a small percentage do get symptoms, and they can even be deadly in less than one percent of individuals.

Report mosquito presence (anonymously, if you like) by calling the Delta Vector Control District, or your local vector control agency, toll-free, at 1-877-732-8606 or by reporting online at, or on its Facebook page (, Twitter (@DeltaVCD), or Instagram (@DeltaVCD) accounts.

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Mosquitoes carrying Zika virus on way to SJ County

From the Manteca Bulletin
August 8, 2019

As if an active population of adult mosquitoes that are testing positive for the West Nile Virus wasn’t enough, San Joaquin County mosquito abatement experts now have to worry about a new type of mosquito that can carry both the Zika virus and other diseases such as dengue fever that has surfaced in neighboring Stanislaus County. 

Last month public health experts warned that a pair of Aedes aegypti mosquitoes were discovered in traps on the east side of Modesto – indicating a possible breeding population – which long confirmed the fears of vector control experts that have been waiting for the mosquitoes to work their way north. 

“Now it’s just only a matter of time before we detect them in San Joaquin County,” said San Joaquin Mosquito and Vector Control District spokesman Aaron Devencenzi. “We check the traps that we have in the South County near the border with Stanislaus County regularly, and just recently our guys have more traps in that area so that we can monitor what is happening.”

Unlike the mosquitoes that carry West Nile Virus – which are active predominantly at dawn and at dusk and are more densely packed in rural areas – the Aedes aegypti mosquito is active during the day and can commonly be found in urban and populated areas. If that wasn’t enough of an issue, Devencenzi said that eradication is extremely difficult because the mosquitoes are able to lay their eggs in only a capful of water, and once they are laid, they are viable even without water present for up to six months. 

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Daytime-biting mosquito shows up in Stockton

From the Record-Net
August 8, 2019

STOCKTON — An invasive mosquito species not native to California has been detected for the first time in Stockton.

On Tuesday, the San Joaquin County Mosquito and Vector Control District collected the species known as Aedes aegypti from the Brookside neighborhood in west Stockton.

The district has been looking for the species for about four years as it creeps up the San Joaquin Valley, setting up traps throughout the county. They were alerted to its presence this week when a resident called the district to report multiple biting mosquitoes during the day, spokesman Aaron Devencenzi said.

District personnel went to the area, collected the mosquitoes and confirmed they were Aedes aegypti, Devencenzi said.

Aedes aegypti has the potential to transmit several viruses, including dengue, chikungunya, Zika and yellow fever, but it should be noted these viruses are not currently transmitted by mosquitoes in California, according to a statement from the local district.

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Four people reportedly sick with West Nile Virus in Tulare County

From FOX 26 News
August 8, 2019

Four cases of suspected West Nile Virus have been reported in Tulare County, according to Tulare County Health.

Three men and one child have caught the virus. Three of those people are from from Visalia, one from Tulare.

Delta Vector Control also reports that St. Louis Encephalitis Virus has been found in Tulare County mosquitoes.

There is currently no vaccine or medication to treat either virus once you have it.

It’s reported that 80% of people that catch West Nile or St. Louis Encephalitis viruses won’t show any symptoms.

Mild symptoms like fever, headache, disorientation, muscle weakness, vision loss, numbness, and paralysis may occur.

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Additional Travel-Related Zika Cases in the USA

From Precision Vaccinations
August 7, 2019

August 7th, 2019 – According to various data sources, there have been 9 additional travel-related Zika virus cases reported since July 18, 2019.

As of August 7, 2019, the states of Florida (29), California (25), Idaho (1), Nebraska (1), New York (1), and Utah (1) have reported 58 travel-related Zika cases this year. 

For privacy reasons, these international traveler’s destinations have not been disclosed.

Additionally, the US Territory of Puerto Rico has confirmed 24 locally acquired Zika cases during 2019. These Zika cases were acquired through the presumed local mosquito-borne transmission during 2019, says the US Centers for Disease Control and Prevention (CDC).   

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Some common garden plants might help keep bugs away

From The Telegraph
August 6, 2019

If mosquitoes, gnats, black flies and no-see-ums are driving you buggy, then consider cozying up to some lavender, marigolds or basil. Scientists question their overall effectiveness, but many fragrant ornamental flowers and herbs grown around the home have properties that can repel insects.

Insect repellents are divided into two primary chemical classes: natural and synthetic. How effective they are depends on the targeted insects and the host plants’ essential oils.

“Plant-derived insect repellents are very volatile compounds that work but exhaust themselves very quickly,” said Walter Leal, a biochemist and distinguished professor at the University of California, Davis. “They’re good, but they should last for a longer time.”

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2 dead birds infected with West Nile virus found in Huntington Beach

From the Los Angeles Times
August 6, 2019

Two dead birds that tested positive for West Nile virus were recently found in Huntington Beach, but there have been no confirmed human cases in the county so far this year, according to the Orange County Mosquito and Vector Control District.

The infected American crows were found in June — one in the area of McFadden Avenue and Bolsa Chica Street and the other near Huntington Beach High School — according to vector control spokeswoman Lora Young.

A total of nine infected birds, including Huntington’s, have been found in the county so far this year. The others were in Cypress, Buena Park and Tustin.

Vector control also collected its first mosquito sample that tested positive for West Nile this year at El Camino Real Park in the city of Orange on July 30. Mosquitoes collected in other area cities haven’t tested positive for the virus, Young said.

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After positive West Nile test, more mosquito spraying planned across valley

August 5, 2019

COACHELLA VALLEY, Calif.- – Mosquito pesticide treatments in the Coachella Valley will be continuing Monday following Friday’s announcement that West Nile Virus has been detected in mosquitoes in Indian Wells for the first time this year.
Aerial and truck-mounted mosquito control applications are underway today in Indio, La Quinta and Mecca, and are planned to begin in Palm Springs tomorrow, according to the Coachella Valley Mosquito and Vector Control District.
While there have been no reported human cases of West Nile Virus in the Coachella Valley this year, 74-year-old Robert Mears of nearby Imperial County was reported to have died of the virus earlier this month. The Vector Control District has also detected St. Louis encephalitis virus in Coachella Valley mosquitoes this year.

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Two L.A. County residents are sick with West Nile — the county’s first cases of 2019

From the Los Angeles Times
August 5, 2019

Two people in Los Angeles County have been diagnosed with West Nile virus, in what officials say are the first two cases in the county this year.

Both people became ill with West Nile, which is transmitted to humans through a mosquito bite, late last month and are recovering, officials said Monday. One lives in the San Fernando Valley and the other in the southeastern region of L.A. County, they said.

“We are glad to hear that these two people are recovering from their West Nile fever infections and wish them well. Every year in Los Angeles County, we see cases of West Nile virus infection, which can be serious, even deadly, especially for people over 50 and those who have existing health problems,” L.A. County health officer Dr. Muntu Davis said in a statement. “Mosquito bites aren’t just annoying, they may make you sick.”

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Mosquitoes collected in Orange test positive for West Nile virus; 9 birds also found with the disease around Orange County

From The Orange County Register
August 5, 2019

Mosquitoes found at El Camino Real Park in Orange have tested positive for West Nile virus, the Orange County Mosquito and Vector Control District announced Monday, Aug. 5. The mosquito sample, collected July 30, was the first batch to test positive for the virus in the county in 2019.

The vector control district also announced, Monday, that a total of nine dead birds infected with the disease were found in Cypress, Buena Park, Huntington Beach and Tustin. Given the number of birds infected, “we anticipate we’ll get more positives (in mosquitoes) with West Nile virus throughout the county,” Lora Young, spokeswoman for the vector control district, said.

No human cases of West Nile virus have been reported in Orange County this year, according to vector control officials.

However, the Los Angeles County Department of Public Health, on Monday, confirmed L.A. County’s first two cases of human West Nile virus in 2019. One resident of the San Fernando Valley and another in the southeastern portion of the county contracted the virus in late July and are in recovery.

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Sacramento-Yolo mosquito district offers free repellent for Tuesday’s National Night Out events

From the Sacramento Bee
August 3, 2019

The Sacramento-Yolo Mosquito and Vector Control District is offering free mosquito repellent to community groups planning outdoor activities for the National Night Out on Tuesday. All you have to do is schedule pickup.

Mosquitoes carry the deadly West Nile virus and can transmit it to birds, humans and other mammals when they bite them. The district reported that, in Sacramento County, seven dead birds and 11 mosquito samples have tested positive for the deadly West Nile virus this year. Placer County also reported a positive mosquito sample, but neither El Dorado nor Yolo counties has found evidence of activity this year.

“We know many people will be outside for this event, and we want to remind the public that personal protection against mosquitoes is critical in the prevention of West Nile virus,” said District Manager Gary Goodman. “We encourage everyone to take advantage of the free repellent we are offering as part of our public outreach program.”

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More West Nile-positive mosquitoes found in L.A. County

From Los Angeles Fox 11
August 2, 2019

 – Another batch of West Nile virus-positive mosquitoes has been collected in Bellflower.

According to the Greater Los Angeles County Vector Control District this is the second group of infected insects captured in the county this year.

Vector-control officials noted that West Nile activity was off to a slow start in the county, but warned the warm weather still to come will likely exacerbate matters.

The district noted that 445 positive mosquito samples have been collected in Southern California.

The first positive sample in the county was found in mid-July in Long Beach. West Nile is transmitted to people and animals through the bite of an infected mosquito. Symptoms from contracting the disease can include fever, headache, body aches, nausea or a skin rash, according to the department.

The symptoms can last for several days to months.

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Mosquitoes capable of carrying the Zika Virus discovered for the first time in Stanislaus County

From ABC 10
August 2, 2019

MODESTO, California — Two aedes aegypti mosquitoes are now held in containers at the East Side Mosquito Abatement District Headquarters in Modesto.

“Not a major surprise that they are here because the population takes awhile to build up to a number where we can catch them in our traps,” said Dr. Wakoli Wekesa, who is the new manager of the East Side Mosquito Abatement District.

He has 30 years of studying mosquitoes across California, having worked in other mosquito control districts.

He says the aedes egypti mosquito has been found in California for years and has been steadily progressing its way northward from Southern California.

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Yikes! More West Nile Bug Danger In LA County

August 2, 2019

Another batch of West Nile virus-positive mosquitoes was collected in Bellflower, the second group of infected insects captured in the county this year, the Greater Los Angeles County Vector Control District announced Friday.

Vector-control officials noted that West Nile activity was off to a slow start in the county, but warned the warm weather still to come will likely exacerbate matters. The district noted that 445 positive mosquito samples have been collected in Southern California outside of the county.

The first positive sample in the county was found in mid-July in Long Beach.

West Nile is transmitted to people and animals through the bite of an infected mosquito. Symptoms from contracting the disease can include fever, headache, body aches, nausea or a skin rash, according to the department. The symptoms can last for several days to months.

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Shasta County reports first positive West Nile virus mosquito sample

From the Record Searchlight
July 29, 2019

A mosquito sample collected in the Cottonwood area has tested positive for the West Nile virus, the Shasta Mosquito and Vector Control District reported Monday morning.

“Although this is our first indication of West Nile virus activity, we know it is endemic in Shasta County and will be a concern every year,” Shasta Mosquito and Vector Control District Manager Peter Bonkrude said in a news release.

The sample was taken in west Cottonwood.

Bonkrude said as warmer temperatures persist, the increase risk for transmitting the virus will continue.

The Shasta Mosquito and Vector Control District reminds residents to take precautions to decrease the risk by draining any standing water that may produce mosquitoes, avoid outside activities at dusk or dawn, and dress in long-sleeves and pants when mosquitoes are active.

Also, defend yourself and your home by using insect repellent, and making sure that screens on doors and windows are in good condition.

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New gene-editing study finds protective genes against Zika virus

From News Medical Life Sciences
July 28, 2019

Tel Aviv scientists have discovered certain genes that protect the host organism against attack by Zika virus, raising hopes of an eventual vaccine or cure for this dreaded viral disease.

The Zika virus, which is rampant in South America, can cause severe damage especially to unborn babies, including fetal death or stillbirth, or serious birth defects which are collectively called the congenital Zika syndrome. This includes such issues as a significant and crippling reduction in head size (microcephaly), neurological anomalies, and retarded development. Over 60 million people have been affected so far by this insect-borne virus, which can also cause the paralyzing disease Guillain-Barre syndrome and other nerve illnesses. However, scientists have not come up with a vaccine or cure for this devastating disease.

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Guest Editor: Mosquito Abatement and Trash Capture Devices

From Forester Media
July 26, 2019

This piece is an abridged version of a feature article by the author that appeared in the Spring 2019 issue of Wing Beats magazine, an official publication of the American Mosquito Control Association.

In August 2012, I investigated a catch basin in the City of San Leandro, CA, that I had inspected for mosquito production many times before. To my surprise, I saw a metal screened box bolted to the wall of the basin covering the outlet pipe. I walked to another catch basin and there was another one, and then another. What were these things, and why were they there?

Trash capture devices (TCD) are installed in catch basins to prevent trash from flowing into creeks, canals, and bays. These devices are a byproduct of the federal Clean Water Act and similar state regulations. Trash capture is a prominent issue in the San Francisco Bay Area as the region set ambitious goals to reduce trash entering waterways, and by 2030 the mandate will be fully implemented statewide in California.

While TCDs come in many shapes, configurations, and designs to maximize trash capture performance, an unintended and problematic consequence is that many pose substantial problems for inspecting and treating catch basins for mosquito larvae without completely dismantling the device. With tens of thousands of catch basins in Alameda County that need to be inspected and treated several times in a season, we quickly realized the profound impact TCDs would have on our ability to control mosquitoes and protect public health.

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Stanislaus County woman infected with West Nile Virus

From the Turlock Journal
July 26, 2019

Health officials reported Wednesday that an area woman diagnosed with a neuroinvasive form of West Nile Virus is the first confirmed human case of the disease in Stanislaus County this season.

The first mosquitoes of the season tested positive for West Nile virus on July 9, the Stanislaus County Health Services Agency reported.

The California Department of Public Health has found West Nile Virus in 21 counties in the state, including two human cases, which does not take into count the recent diagnosis for the Stanislaus County woman. The state has seen one death from the virus this year.

Mosquitoes become infected with West Nile Virus when they feed on infected birds. Infected mosquitoes can then spread West Nile Virus to humans and other animals when they bite, according to the Centers for Disease Control.

Approximately 1 in 5 people who are infected with West Nile virus will develop symptoms such as fever, headache, body aches, joint pains, vomiting, diarrhea, or rash. Less than 1 percent will develop a serious neurologic illness such as encephalitis or meningitis (inflammation of the brain or surrounding tissues). About 10 percent of people who develop neurologic infection due to West Nile virus will die, according to the CDC.  People over 50 years of age and those with certain medical conditions, such as cancer, diabetes, hypertension, kidney disease, and organ transplants, are at greater risk for serious illness.

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First case of West Nile virus for 2019 reported in Sutter County

From the Sacramento Bee
July 26, 2019

West Nile virus has been detected in Sutter County for the first time so far in 2019, in one human patient as well as in mosquito samples, the Sutter-Yuba Mosquito and Vector Control District said Friday.

The Sutter County Health Department reported an asymptomatic human had tested positive for West Nile virus, the vector control district said in a news release. Recent mosquito samples west of Yuba City also tested positive, the release said.

The district warns mosquito populations may increase with high temperatures, which are incoming this weekend.

Any resident who sees a dead bird should report it to the state Department of Public Health, at


Genetic screen identifies genes that protect cells from Zika virus

From Science Daily
July 25, 2019

A new Tel Aviv University study uses a genetic screen to identify genes that protect cells from Zika viral infection. The research, led by Dr. Ella H. Sklan of TAU’s Sackler School of Medicine, was published in the Journal of Virology on May 29. It may one day lead to the development of a treatment for the Zika virus and other infections.

The study was based on a modification of the CRISPR-Cas9 gene-editing technique. CRISPR-Cas9 is a naturally occurring bacterial genome editing system that has been adapted to gene editing in mammalian cells. The system is based on the bacterial enzyme Cas9, which can locate and modify specific locations along the human genome. A modification of this system, known as CRISPR activation, is accomplished by genetically changing Cas9 in a way that enables the expression of specific genes in their original DNA locations.

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Opinion: California faces rising danger of mosquito-borne diseases

From the East Bay Times
July 24, 2019

In the past year, California has experienced multiple public health crises. Last October, San Diego County health authorities declared an end to a Hepatitis A outbreak that killed 20 people and sickened nearly 600. That same month, health officials warned the public of a typhus outbreak in downtown Los Angeles. And now public health departments across the state are scrambling to prevent a widespread outbreak of measles.

But when most people think about mosquitoes, they consider them nuisances that cause itchy bites. They don’t think about the public health risk and potential for mosquito-borne disease transmission. However, the threat of mosquito-borne diseases, especially West Nile virus, is also very serious and must be a public-health priority.

That’s why I’m advocating for more state funding to support vector-borne-disease research, surveillance and data collection. It’s critical that mosquito- and vector-control professionals and public health officials have resources they need to track and predict the emergence of mosquito-borne diseases and efficiently respond.

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West Nile disease strikes in Stanislaus County. Here’s what you need to know

From Merced Sun-Star
July 24, 2019

Stanislaus County health officials have reported a serious case of west Nile illness as prime conditions for the virus create a threat to the public.

The patient was only identified as a female in the news release Wednesday from the county Health Services Agency.

She was diagnosed with the potentially deadly neuroinvasive disease, which can result in long-term disabilities.

People may come down with symptoms of the endemic west Nile virus after they’re bitten by infected mosquitoes. According to health agencies, 1 in 5 will have symptoms including headache and fever possibly lasting for several weeks.

How to protect yourself from mosquitoes during monsoon season

July 24, 2019

INDIO, Calif. – With monsoonal moisture comes unwanted pests. Mosquitoes carrying deadly viruses could be lurking around your backyard.

News Channel 3’s Caitlin Thropay spoke with Coachella Valley Mosquito and Vector Control District to find out how you can beat the bite.

Three steps they recommended are to, “dump it, drain it and scrub it clean.” If you have any “kiddy” pools, tires lying around, bird baths, flower pots, plant saucers or anything that holds still water in it, you need to follow these simple steps. 

“This is a really unprecedented year for West Nile Virus activity in the Coachella Valley and it’s also been a pretty productive year for mosquitoes because of the weather we have been having all year,” General Manager of Coachella Valley Mosquito and Vector Control District, Jeremy Wittie told News Channel 3. 

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Tree swallows may be answer to mosquito problem

From The Monroe News
July 23, 2019

Have you ever been bothered by mosquitoes or other flying insects while enjoying quiet time on your deck or patio?

Have you ever been bothered by mosquitoes or other flying insects while enjoying quiet time on your deck or patio?

If so, let me introduce you to a tree swallow family.

These colorful, high flying, acrobatic creatures may be an answer to enjoying that quiet time on your deck or patio and with added entertainment. During an average day, adult tree swallows soar, swoop, and dive to consume about 2,000 flying insects.

Multiply that by two, a male and female, and four to seven nestlings, you can see how this might improve your outdoor enjoyment.

How can you enjoy these beautiful active birds?

After a one to two-month migration north from California, Mexico and Central America, tree swallows find their way to our area.

They are cavity nesters but are unable to dig their own nest cavities. When planning to start their family, they look for an old woodpecker hole or a cavity in a dead tree or a bluebird nesting box. They nest in a cavity with the same size entrance as the eastern bluebird.

I have two bluebird boxes in my backyard, one used by bluebirds and one used by tree swallows, 75 feet apart and facing each other.

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Getting Eaten Alive By Mosquitoes? Here’s All You Ever Needed to Know

From NBC Los Angeles
July 20, 2019

It’s that time of year again: it’s time for barbecuing, basking in the sun, and of course, fending off annoying bites from mosquitoes. 

What’s worse, in Southern California, is the presence of an aggressive ankle-biter mosquito that will bite multiple times, and doesn’t wait for dusk — they’ll attack right in the middle of the day, or even inside your house. That’s atypical mosquito behavior, at least for the kinds that are native to Southern California. 

If you’ve noticed you’ve suddenly been bitten multiple times around your ankles, you were likely victim to the Aedes mosquito, which officials believe arrived on a container ship from Asia. It’s an invasive species, meaning not native to Southern California, and fueled by bloodlust (basically). And they have the potential to carry harmful diseases, like in the case of one 74-year-old Imperial County man who died after contracting West Nile virus, which was the first person to die of the virus in California in 2019. 

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Science bites back . . . Chinese trial wipes out 99% of deadly mosquitoes

From The Times
July 19, 2019

Chinese scientists say they have almost eradicated a virus-carrying mosquito from two islands by releasing infected males into the population.

It is hoped that the study will give officials new tools to fight diseases such as dengue fever and zika.

Asian tiger mosquitoes were exposed to gamma radiation and infected with strains of a parasitic bacterium, according to the journal Nature. Two hundred million of the infertile insects were released on the islands of Shazai and Dadaosha in southeast China.

Female mosquitoes only mate once, so if the male is infertile she will not reproduce. At the end of the two-year trial the native mosquito populations were largely gone.

The work “almost eliminated a notoriously difficult-to-control vector mosquito from the test sites”, Peter Armbruster, a…

West Nile virus found in mosquitoes in Long Beach

From Fox LA
July 19, 2019

 – Mosquitoes collected in Long Beach have tested positive for West Nile virus. It’s the first detection of the virus this year in the county, the Greater Los Angeles County Vector Control District announced Friday. 

“West Nile virus is endemic in Los Angeles County. When temperatures increase, so do mosquito populations and disease risk, which pose a serious public health threat for our communities,” said Susanne Kluh, director of scientific-technical services at the district.

According to the district, West Nile virus activity has been increasing steadily throughout California this year.

West Nile is transmitted to people and animals through the bite of an infected mosquito. Symptoms from contracting the disease can include fever, headache, body aches, nausea or a skin rash, according to the department. The symptoms can last for several days to months.

“Our agency will continue monitoring virus activity and controlling mosquitoes in affected areas,” said Anais Medina Diaz, public information officer for the district. “But it is very important residents take precautions in their own communities by wearing insect repellent and frequently removing standing water to eliminate mosquito sources.”

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Officials work to tackle mosquitoes in Elk Grove

From KCRA 3
July 19, 2019

The Sacramento-Yolo Mosquito and Vector Control District said it’s received several calls from neighbors concerned about the mosquito population.

Jax, 9, was playing soccer Tuesday when the mosquitoes started going after him.

“These mosquitoes were going by my shin guard and my socks,” Jax said, pointing to the back of his leg. “Then one by one, they kept coming towards me.”

The bites started swelling and his skin turned red. His mom blamed the mosquitoes for the problem and took her son the doctor the next day.

“It was blistering, and (the doctor) didn’t want it to pop or anything,” his mother Jennifer said. “(The doctor) said to just air it out. She gave us some antibiotics to take and then some ointment for his legs.”

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Protect your kids and yourself from bug-borne diseases like Lyme

From Baby Center
July 18, 2019

Tick-borne diseases, in particular, have skyrocketed in the past few years. Thankfully, there are a number of steps you can take to lower the risk of bug bites. These include:

  1. Wear repellent: Use EPA-registered insect repellent if you’re in an area with mosquitos or ticks. Check to make sure that the repellents you use are safe for your child.
  2. Avoid tick habitats: Wooded areas, leaf-covered ground, and places with tall grass are popular with these blood-sucking insects. If you do venture into these locations, wear long pants and check your body and clothing for ticks afterward, and take a shower. Regularly check for ticks on your pets as well.
  3. Wear loose, long-sleeved clothing: Light-colored, tightly woven clothing that covers the arms and legs can help protect you and your children from mosquito bites.
  4. Use screen doors and windows: Repair any tears in your screens at home, and stay in lodgings that have screens or air conditioning to keep mosquitos at bay.
  5. Control bugs around your home: Empty all containers of water, such as buckets and birdbaths, so they don’t become a breeding ground for mosquitos. Remove leaf litter and clear tall grasses and brush around homes and children’s play areas to help reduce tick populations.
  6. International travelers should be especially alert to bug-borne disease risks in their destination country and take appropriate safety measures. You can use this interactive search tool to check for health warnings by country, courtesy of the Centers for Disease Control and Prevention (CDC). It includes search options specific to pregnant women and families traveling with kids.

Of course, the above suggestions are no guarantee against a bite. And no one is immune. Americans from every state have contracted illnesses from bug bites. 

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Officials In Fresno County Alert People About Possible Spread of West Nile Virus

From the International Business Times
July 17, 2019

he officials of Consolidated Mosquito Abatement District in Fresno County, California, have alerted people in the region about a possible spread of West Nile Virus.

The officials found 46 Culex mosquitoes carrying potentially serious viruses. While 43 of the dangerous mosquitoes carried West Nile virus, the rest of them had St. Louis encephalitis.

“Every year it’s here, so even though we do surveillance, we’re always collecting West Nile virus mosquitoes in this area,” abc30 quoted Katherine Ramirez, who is with the Consolidated Mosquito Abatement District.

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46 mosquitoes with serious viruses found in Fresno County

From ABC 30
July 16, 2019

FRESNO, Calif. (KFSN) — The West Nile virus has not made any humans sick in Fresno County this year, but the potential for infections is growing.

West Nile virus arrived in Fresno County in 2004 and the Consolidated Mosquito Abatement District has stayed busy ever since.

“Every year it’s here, so even though we do surveillance, we’re always collecting West Nile virus mosquitoes in this area,” said Katherine Ramirez with the Consolidated Mosquito Abatement District.

Employees go to ponding basins and neglected swimming pools and use fish or larvicide to control the mosquito population.

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Mosquito discoveries put bite on fresh flowers at Visalia Cemetery

From the Visalia Times Delta
July 12, 2019

The Visalia Public Cemetery District is asking people not to bring fresh flowers to the cemetery after health officials found mosquitos that can carry West Nile and other viruses in standing water containers. 

On June 19, Delta Vector found invasive mosquitoes in three out of four samples at the cemetery. 

Delta Vector is the testing agency tasked with placing traps and identifying West Nile across Tulare County. 

After getting the mosquito news, the cemetery district hired a temporary crew to turn over flower vases and containers to eliminate standing water.

That temporary crew worked 135 hours over seven days to complete this project, cemetery managers said. 

The cemetery is close to 50 acres in size and there are more than 45,000 graves. 

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Mosquitoes test positive for deadly West Nile virus near Florin area in Sacramento County

From the Sacramento Bee
July 11, 2019

The Sacramento-Yolo Mosquito and Vector Control District reported Wednesday that, for the first time this year, a mosquito sample collected within the two-county district has tested positive for West Nile virus.

This particular sample was collected near the Florin area of south Sacramento County, officials said, and the news did not come as a surprise to them because a dead bird tested positive for the disease last week near Elverta in north Sacramento County.

“As we expected, after finding the first positive bird … we are finding virus in the mosquito populations, “ said Gary Goodman, the district manager. “With the very warm weather expected over the next few days, we expect (West Nile virus) activity to quickly ramp up.”

Luz Robles, the district’s public information officer, said cool weather this year likely has helped to keep mosquito activity low. By this time in 2018, there was more activity because temperatures were high.

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UCR Researchers to Target Mosquito Egg Production to Curtail Disease

From Pest Control Technology
July 11, 2019

RIVERSIDE, Calif. — Entomologists at the University of California, Riverside have received a five-year grant of $2.44 million from the National Institute of Allergy and Infectious Diseases, or NIAID, to investigate the role hormones play in the female mosquito’s ability to use human blood for egg production.
Vector mosquitoes need vertebrate blood to develop each batch of their eggs. As a result, reproduction in female mosquitoes is closely linked to blood feeding. The NIAID funding — a competitive National Institutes of Health grant renewal — will allow the entomologists to introduce novel research tools for genetic manipulation, such as CRISPR, in their exploration of the genetic basis for the hormonal control of mosquito reproduction.
“A clear understanding of the molecular mechanisms regulating egg development in mosquitoes can play a critical role in our coming up with innovative and novel vector control methods,” said Alexander Raikhel, a distinguished professor of entomology who will lead the project along with Sourav Roy, an assistant professional researcher who received his doctorate at UCR and joined the Raikhel lab in 2011.