Female mosquitoes get choosy quickly to offset invasions

From Science Daily
August 16, 2018

At issue is the displacement of Aedes aegypti (yellow fever) mosquitos by a cousin species, Aedes albopictus (Asian tiger), which occurred in the southeastern United States in the 1980s. In this “battle of the Aedes,” the invading A. albopictus decimated A. aegypti populations throughout the Southeast, leaving smaller A. aegypti populations in Key West, Florida, Arizona and a few other southern locales. A. aegypti mosquitoes carry and spread many diseases that harm humans, including Zika, dengue fever and chikungunya.

Part of the takeover was attributed to how the larvae of each species grew; A. albopictus mosquitoes seemed to be able to outcompete the native mosquitoes. But another factor also played a huge role in the battle: When A. aegypti females mated with A. albopictus males — a genetic no-no — those females became sterile for life, a process called “satyrization.” A. albopictus females didn’t face the same fate; no offspring were produced when they mated with A. aegypti males, but they were later able to be fertile when mating with males of their own species.

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NIH begins clinical trial of live, attenuated Zika vaccine

From EurekAlert!
August 16, 2018

Vaccinations have begun in a first-in-human trial of an experimental live, attenuated Zika virus vaccine developed by scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. The trial will enroll a total of 28 healthy, non-pregnant adults ages 18 to 50 at the Johns Hopkins Bloomberg School of Public Health Center for Immunization Research in Baltimore, Maryland, and at the Vaccine Testing Center at the Larner College of Medicine at the University of Vermont in Burlington. NIAID is sponsoring the trial.

Although most people experience a mild illness or no symptoms when infected with Zika virus, babies born to women infected with Zika virus during pregnancy may have birth defects and/or develop health problems in their early years.

Zika virus is primarily transmitted to humans by the bite of an infected mosquito or can be transmitted through sex. As a result, the Centers for Disease Control and Prevention (CDC) advises that pregnant women should not travel to areas with risk of Zika. CDC also recommends that partners of pregnant women and couples considering pregnancy should know pregnancy risks and take certain precautions. The U.S. Zika Pregnancy and Infant Registry has recorded the number of pregnant women with laboratory evidence of possible Zika virus infection since 2015. As of July 17, 2018, the registry had recorded 2474 pregnancies in states and the District of Columbia and 4900 pregnancies in U.S. territories and freely associated states.

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West Nile virus found in mosquitoes in Santa Clara, Sunnyvale

From the Mercury News
August 14, 2018

West Nile virus was detected in mosquitoes collected from an area around the 94087, 95050 and 950512 zip codes in parts of Santa Clara and Sunnyvale, the Santa Clara County Vector Control District announced Monday.

The vector control district is planning a targeted treatment operation on Wednesday in an effort to prevent human cases of West Nile virus, which has resulted in 292 fatalities statewide since 2003.

The vector control district said the truck-mounted treatment will begin at 11 p.m. and last about three hours. The boundaries of the area being treated include Cabrillo, Machado, Santa Maria and Warburton avenues to the north, Long Street, Scott Boulevard, Fairfield Avenue and Robin Drive to the east, E. Homestead Road, Lehigh and Kenyon drives, Forbes and Taft avenues to the south and Swallow and Teal drives, Turnstone Way, Halford Avenue and Lawrence Expressway to the west. The map is available here.

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In the war on West Nile Virus, mosquito-eating fish are the latest biological weapon

From the Los Angeles Daily News
August 14, 2018

Millie Cavafian lives in South Pasadena next door to a vacant home with an old swimming pool teeming with green algae.

“Five minutes out of the house and we are bitten by mosquitoes. We have kids and they have complained about it,” she told Marc Mitchell, vector control specialist.

Mitchell scooped several mosquito fish from his bucket and let them swim free into the murky pool waterAt one end of the kidney-shaped pool, rings popped up in the green muck marking where mosquito larvae were jumping up for air.

“Thank you for addressing that one over there,” Cavafian said to him.

One look at these skinny topminnows being dropped into pools, fountains and flood control channels and you would never know they have a voracious appetite.

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Experts recommend longer follow-up period for children exposed to Zika

From Healio
August 14, 2018

For children with suspected or confirmed exposure to Zika virus in utero, the CDC recommends screening for signs of congenital Zika syndrome and other birth defects by 1 month of age. The agency also recommends evaluating children for microcephaly until age 24 months and older. However, authors of a recent editorial published in Trends in Microbiology are now suggesting that because the effects of Zika virus infection may extend well into childhood, regular screening may be necessary through adolescence.

Approximately one in 10 U.S. pregnant women with confirmed Zika virus infection had a fetus or baby with birth defects in 2016, according to the CDC. The highest risk for birth defects occurred when mothers were infected in the first trimester.

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From Action News Now
August 13, 2018

Chico, Calif.– Maybe the most infamous pest of the summer season is the mosquito – with reports of West Nile Virus in recent years across the North State, these pests can be a serious problem.

We know already that there are several mosquitoes in Butte County plagued with WNV; Honcut, Palermo, and Dayton – the virus is here.

With increasing mosquito populations, the Butte County Mosquito and Vector Control District urges residents to take all precautions necessary to drain any and all unneeded standing water, report any suspected mosquito-breeding sites and protect themselves from the bites of mosquitoes.

Remove standing water on your property from plant saucers, clogged gutters and garden containers — they’re potential breeding sites.

There’s an array of products marketed to help deal with mosquitoes and other annoying flying critters: sprays, herbs, zappers, citronella, coils, lanterns, candles, oils, dunks, fogs, torches, table-top diffusers, wipes, lotions and one-time yard treatments.

And another creepy-crawly that makes itself known in warm weather is the spiders.

They have plenty of benefits, but that doesn’t mean we want to see them all over our homes.

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West Nile virus found in dead birds in eastern Contra Costa County

From The Mercury News
August 11, 2018

West Nile virus was found in two dead birds and mosquitoes in eastern Contra Costa, the county Mosquito & Vector Control District said Friday.

The district warns the virus peaks in August and September, when baby birds leave nests and mosquitoes bite more often.

So far in 2018, there was one other dead bird and four other groups of mosquitos who tested positive for the virus in Contra Costa County, the district said.

“This puts people at higher risk of virus transmission and so it’s important for Contra County residents to take steps now to avoid mosquito bites,” said Steve Schutz, the district’s scientific programs manager.

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Dead birds, mosquitoes test positive for West Nile Virus in Discovery Bay area

From 7 News
August 11, 2018

Two dead birds found in Discovery Bay have tested positive for West Nile virus, according to the Contra Costa Mosquito & Vector Control District.

In addition, mosquitoes found in Oakley and Discovery Bay also tested positive, the district said Friday in a news release.

There have been a total three dead birds and five groups of mosquitoes so far this year to test positive for the virus in Contra Costa County, according to the district.

“West Nile virus activity typically peaks in August and September, when baby birds have left their nests and mosquitoes begin to feed on humans more often,” Steve Schutz, the district’s scientific programs manager, said in a statement.

Last month, the district’s sentinel chicken flock in Martinez tested positive, the first sign of West Nile virus activity in the central part of Contra Costa County.

Since 2005, 63 Contra Costa residents have been diagnosed with West Nile virus, according to the district. In 2006, two people died from the disease.

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Press Release from Contra Costa MVCD
August 10, 2018

CONCORD, CALIFORNIA – The Contra Costa Mosquito & Vector Control District is reporting mosquitoes from Oakley and Discovery Bay and two dead birds from Discovery Bay have tested positive for West Nile virus. This is the fifth group of mosquitoes and the third  dead bird from Contra Costa County so far this year to test positive for the virus.  
According to the District’s Scientific Programs Manager Steve Schutz, Ph.D., “West Nile virus activity typically peaks in August and September, when baby birds have left their nests and mosquitoes begin to feed on humans more often. This puts people at higher risk of virus transmission and so it’s important for Contra County residents to take steps now to avoid mosquito bites.”
Mosquitoes that can transmit West Nile virus are active at dawn and dusk. 
Steps to take now to avoid mosquito bites:
  • Stay indoors in the evening when mosquitoes can be present 
  • Wear mosquito repellent when outside

Repellents containing DEET, Picaridin, or Oil of Lemon Eucalyptus are most effective and are recommended by the Centers for Disease Control and Prevention (CDC).

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Mosquito known to carry Zika and other viruses found in Ontario

From the Daily Bulletin
August 10, 2018

A mosquito known to transmit the Zika virus has been discovered in Ontario.

The Aedes aegypti, known as the Yellow Fever mosquito, was found in a trap near Euclid Avenue and Walnut Street, according to a news release from the West Valley Mosquito and Vector Control District.

This is the first time the mosquito has been found in Ontario. In July, it was found in Montclair.

The small, black and white mosquitoes are closely associated with human dwellings. They will actively pursue people both during the day and the evening, according to the District.

They are also known transmitters of Chikungunya, Dengue, and Yellow Fever viruses.

District officials are urging residents to remove all standing water sources, such as buckets, tires and planter pots. They also recommend scrubbing the inside of containers to dislodge eggs deposited above the water line.

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Mosquitoes Carrying Encephalitis Virus Found On Westside

From the Venice Patch
August 10, 2018

LOS ANGELES, CA — A batch of mosquitoes trapped in Playa Vista tested positive for the St. Louis Encephalitis virus, which is similar to West Nile virus, vector control officials said Friday.

The mosquitoes are the first found to be carrying SLEV in Los Angeles County this year. There has not been a human case of the virus in Los Angeles County since 1997. Mosquitoes carrying the virus have been found in the county each of the past two years.

Like West Nile, SLEV is transmitted to people through bites from infected mosquitoes. Also like West Nile, most people who contract the virus do not show any symptoms. Others will develop flu-like symptoms, such as fever, headache and body aches.

In the most severe cases, SLEV and West Nile virus can affect the central nervous system and lead to meningitis or encephalitis, potentially causing death or long-term disabilities. People over age 50 years and people with compromised immune systems are at greater risk of experiencing severe symptoms.

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From Action News Now
August 9, 2018

OROVILLE, Calif. – The Butte County Mosquito and Vector Control District (BCMVCD) said various groups of mosquitoes, and some chickens have been infected with West Nile Virus in the county.

At least 17 mosquito pools and 11 sentinel chickens tested positive for the virus, according to District Manager Matthew Ball from BCMVCD.

The mosquitos were found in south, central and northern areas of Butte County making it a total of 35 mosquito pools with one wild dead bird, officials said.

Butte County officials are urging residents to drain any and all un-needed standing water and to report any suspected mosquito-breeding sites to the district.

The Thursday announcement comes a week after the Butte County Public Health Department announced its first human case of WNV for 2018.

Officials said WNV is continuing to increase in California and that Butte County is following that trend.

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Mosquito Season Getting Longer

August 8, 2018

The number of days each year that are suitable for disease transmission by mosquitoes is rising in much of the U.S., as temperatures climb with climate change. This can increase the risk of mosquito-borne diseases such as Zika and West Nile. Following research from Stanford University, Climate Central analyzed the number of days in the spring, summer, and fall each year with an average temperatures between 61°F and 93°F, which is the range for transmission of diseases spread by Aedes or Culex type mosquitoes. Of the 244 cities analyzed, 94% are seeing an increase in the number of these “disease danger days.”

Reno leads the list of cities with additional disease danger days, averaging an additional 52 days per year in that temperature range compared to a half-century ago. The top 10 cities can be found in the report and cover a variety of climates across the U.S. For example, San Francisco, Tucson, and Erie all have more than four additional weeks each year when transmission is possible. Baton Rouge’s “disease danger days” has increased by 9 days over the last 47 years.

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Ohio State Researchers Finding Early Success With Zika Vaccine

August 8, 2018

Ohio state researchers may have come up with an effective Zika vaccine. Symptoms from the primarily mosquito-borne disease are often mild, but the virus can lead to birth defects when it’s contracted by pregnant mothers.

According to the World Health Organization, the threat of Zika has calmed since a 2015 epidemic in the Western Hemisphere. But without an effective vaccine the disease remains a risk.

Shan-Lu Liu, who’s part of a team from Ohio State, says their focus was on a protein created within a virus-infected cell, rather than just a weakened version of the virus like many other vaccines.

“For Zika virus, it’s a little different because people have found Zika virus’ antibodies, against Zika virus, can even make the disease more severe,” Liu says.

And because Zika is similar to other diseases like Dengue fever, the team – headed up by Jianrong Li – were concerned a vaccine could make those other infections worse, too.

Liu explains they’ve avoided that reaction by adding the protein, known as NS-1, which the virus normally produces inside a host cell to replicate itself. To get the proteins into the body, the research team is using a weakened version of a virus that affects cattle but has no effect on people.

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Babies with Zika-related Health Problems Continue to Need Attention

From the CDC
August 7, 2018

About 1 in 7 babies now 1 year or older who were born to women with Zika virus infection during pregnancy had one or more health problems possibly caused by exposure to the virus before birth, according to the latest Vital Signs report. Some of these problems were not apparent at birth.

About 4,800 pregnancies from areas with Zika (Puerto Rico, American Samoa, U.S. Virgin Islands, Federated States of Micronesia, Republic of Marshall Islands) in the U.S. Zika Pregnancy and Infant Registry (USZPIR) had a laboratory result showing possible or confirmed Zika virus infection between 2016 and 2018. From these pregnancies, 1,450 babies were at least 1 year old by February 1, 2018, and had any follow-up care reported to the USZPIR. Many of these babies did not receive all the recommended screenings for health problems potentially related to Zika virus. Careful monitoring and evaluation of these children is essential to ensure early detection of possible disabilities and referral to early intervention services.

“We know that Zika virus infection during pregnancy can cause serious health problems in babies, such as birth defects and vision problems, including conditions not always evident at birth,” said CDC Director Robert Redfield, M.D. “We are still learning about the full range of long-term health problems these babies could face. We thank clinicians for their continued commitment to conduct all necessary tests and evaluations to ensure appropriate care.”

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Invasive crayfish lead to more mosquitoes and risk of disease in Southern California

From Phys.org
August 7, 2018

Invasive red swamp crayfish are a serious problem in the Santa Monica Mountains and other parts of Southern California. They devastate native wildlife, including threatened species such as the California red-legged frog, throwing off the natural balance of ecosystems.

They also pose a threat to people, according to a new paper in the journal Conservation Biology. The study is based on field research in the Santa Monica Mountains and lab experiments at UCLA La Kretz Center for California Conservation Science.

Mosquitos are notorious vectors that spread diseases such as malaria, Zika and West Nile virus. In the mountains, mosquito populations are kept in check by dragonfly nymphs, which voraciously consume their aquatic larvae. But invasive crayfish disrupt that predator-prey relationship, killing and driving dragonfly nymphs from waterways. And while crayfish also consume mosquito larvae, they’re simply not as good at it, the researchers found.

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West Nile Virus Confirmed in Dead Bird and Mosquitoes in Brentwood, Discovery Bay

From East County Today
August 4, 2018

CONCORD, CALIFORNIA – The Contra Costa Mosquito & Vector Control District is reporting a dead bird from Brentwood and mosquitoes from Discovery Bay have tested positive for West Nile virus. This is the second group of mosquitoes from Discovery Bay and the first dead bird of the year from Contra Costa County to test positive for the virus.

This virus activity serves as an important reminder that residents should wear repellent to reduce the risk of mosquito bites, especially as summer heat continues, prompting residents to delay outdoor activities until temperatures cool in the evening. The mosquitoes that can transmit West Nile virus are active at dawn and dusk.

According to the District’s Scientific Programs Manager Steve Schutz, Ph.D., “Although this is the second group of mosquitoes from Discovery Bay to test positive for West Nile virus, virus transmission can occur anywhere in the county so it’s very important to wear repellent if you’re going to be outdoors in the evening.”

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Mosquitoes Test Positive For Encephalitis, West Nile

From the Palm Desert Patch
August 3, 2018

COACHELLA VALLEY, CA – “Persistent virus activity” in Mecca stemming from disease-carrying mosquitoes has led local vector control officials to call for increased efforts to control the Eastern Coachella Valley mosquito population and reduce transmission of West Nile and St. Louis Encephalitis in the region, beginning with a round of helicopter and truck-mounted spraying in the city that started Thursday.

Mosquitoes from Mecca have tested positive for St. Louis Encephalitis, while West Nile virus has been detected in mosquitoes found in Thermal, according to the Coachella Valley Mosquito and Vector Control District.

The detections prompted the district to call for a round of truck- mounted spraying during the early mornings and helicopter aerial applications in the evenings through Saturday.

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From Action News Now
August 2, 2018

The first confirmed human case of West Nile Virus in Butte County has been announced Thursday morning by the Butte County Public Health Department.

According to Lisa Almaguer from public health, there have been 10 human infections of the virus as of July 10.

The virus is typically active from July through October with August being the peak month.

West Nile Virus is spread to humans by animals by the bite of an infected mosquito, once they feed on infected birds, according to public officials.

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The case for greater focus on mosquitoes, ticks in epidemiology

From Science Daily
August 2, 2018

The textbook approach to managing disease outbreaks focuses on three factors — pathogen, host, and environment — but it leaves out one critical component in the case of afflictions such as Zika, malaria, and Lyme: the insect or arthropod responsible for transmission to humans. A new report proposes a new version of the classic ‘epidemiologic triad’ that better reflects the complexities of managing vector-borne diseases.

The emergence of the mosquito-borne Zika virus captured the world’s attention in 2016, and likewise the continued rise of tick-borne Lyme disease in the United States has highlighted the need for robust response capabilities to vector-borne disease. The classic “epidemiologic triad,” however, is due for a revision in the case of infections spread primarily by insects and related arthropods, and a new report in the Annals of the Entomological Society of America proposes a new version that better reflects the complexities of managing vector-borne diseases.

“Rather than focusing on managing diseases at the host or pathogen level, we suggest the focus should be at the environmental and vector levels, an approach known as integrated vector management, or IVM,” says Natalia Cernicchiaro, DVM, MS, Ph.D., assistant professor in the Department of Diagnostic Medicine and Pathobiology at Kansas State University and senior author on the report. “Management strategies applied at these levels tend to be more sustainable and effective.”

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Sacramento Area Is Set to Receive an Aerial Insecticide Spraying

From Gazette Day
August 2, 2018

To curb the ballooning threat of West Nile Virus, an aerial insecticide spraying has to be conducted. The officials reported that the spray would take place in Elk Grove, the neighborhood’s south of Fruitridge, and the pocket. The spraying will begin on Monday and continue till Tuesday. The Sacramento Vector Control District reported that the spraying would kill the insects that transmit the virus. The announcement came after reports that the Sacramento city unintentionally elevated the risk of its residents contracting the virus courtesy of the developing bodies of stagnant waters that are ideal for mosquito breeding. The Sacramento Vector Control said that the sprayings were scheduled to take place from 8 PM to 12 AM on Monday and Tuesday. A news release said that the spraying is meant to cover about 41,000 acres in area.

The district’s website is reported to contain a mosquito treatment notification service including a communicating map so that the residents can freely figure out whether they are in the spraying zone. Gary Goodman, the district manager, said that it was paramount that they act fast to decrease the risk of the residents contracting West Nile virus and also protect the public. This is especially during the hot summer when the mosquito population is immensely high. When the numbers of these insects are high, the more the residents are at risk of contracting the virus.

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Health officials confirm case of West Nile virus in Tuolumne County

From The Union Democrat
July 31, 2018

A person in Tuolumne County tested positive for West Nile virus last week, the first time the sometimes deadly mosquito-borne illness has been detected in a human locally since 2005.

Dr. Bob Bernstein, county health officer, said that staff from the county’s Public Health and Environmental Health departments are investigating how the person may have been exposed to a mosquito infected with the virus.

“This is a rare event in our county,” he said.

Bernstein noted that more people in the county could have come down with West Nile since the last reported case in 2005 and simply not have known it.

Symptoms of the disease are typically not worse than those of a common flu, if even that.

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County to abate mosquitoes near State Recreation Area on Monday

From the Benicia Herald
August 1, 2018

The Solano County Mosquito Abatement District (Solmad) will be working to thin the mosquito population near Benicia State Recreation Area on Monday, the city announced.

Between 6 and 7:30 a.m. Monday, Aug. 6, Solmad officials will be doing an area application of larvicide by helicopter on the south side of Interstate 780 running into Southampton Bay near the State Recreation Area. The park will be closed during this time, and advance notice will be given starting Friday. The goal is to diminish the number of mosquitoes who may be carrying diseases.

 In addition to causing severe annoyance and allergic reaction, mosquitoes found in California are capable of spreading many diseases to humans and animals including Chikungunya, Dengue, Filariasis (canine and feline heartworm), Malaria, Saint Louis encephalitis (SLE), West Nile virus (WNV), Western Equine encephalitis (WEE), Yellow fever and Zika,” the Mosquito Vector and Control Association of California (MVCAC) wrote in a statement. 

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FIU Researchers Invent Machine That Can Detect Zika in 40 Minutes

From the Miami New Times
July 30, 2018

It’s been two years since Miami’s Summer of Zika, when everyone was freaked out about mosquitoes and your friends all canceled their trips to Florida. But although the public frenzy about the virus has since died down, dozens of Floridians are still being diagnosed with Zika. According to the Department of Health, at least 59 travel-related cases have been reported across the state so far this year.

Unfortunately, testing for Zika remains a somewhat lengthy process. Although very reliable, the commonly used urine test can detect the virus only two weeks after the onset of symptoms, and getting the results can take up to three weeks.

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Mosquitoes in Lake County test positive for West Nile virus

From Lake County News
July 28, 2018

LAKEPORT, Calif. – One mosquito sample collected in Lake County has tested positive for West Nile virus this week, health officials reported Friday.

The mosquitoes, Culex tarsalis, or Western encephalitis mosquito, were collected in Lower Lake on July 26, according to the Lake County Vector Control District.

The district reported that this is the first detection of WNV in Lake County in 2018.

The Lake County Vector Control District traps and tests mosquitoes throughout the county to identify the areas that have the highest risk, and targets those areas for source reduction and treatment using an integrated vector management program. 

“The hot weather we’ve had this summer is perfect for both West Nile virus and mosquitoes to multiply quickly,” said Jamesina Scott, Ph.D., district manager and research director of the Lake County Vector Control District. “This is the first West Nile virus we’ve found in Lake County this year, and in most years, we continue to find West Nile virus into September.”

No other West Nile virus activity has been detected in Lake County yet this year. Statewide, 24 California counties have detected WNV this year, mainly in mosquitoes. Twelve human cases of West Nile virus illness have been reported in California residents this year. 

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Mosquitos in San Fernando Valley Test Positive for West Nile Virus

From NBC Los Angeles
June 28, 2018

Summer is in full swing in Southern California, and after a brief early lull, so is the West Nile virus.

Mosquito samples collected in Sherman Oaks and Porter Ranch tested positive for the virus in the past week, the Greater Los Angeles County Vector Control District announced Saturday.

With only three positive samples this year – including one a week ago – the inevitable annual West Nile virus infestation is off to a slower start in 2018, the district said.

“Last year [at this time] we already had 43 positive samples reported,” district Director of Scientific Technical Services Susanne Kluh said in a statement.

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Press Release From Contra Costa MVCD
July 26, 2018

West Nile Virus Activity Increases with Prolonged Heat

CONCORD, CALIFORNIA – The Contra Costa Mosquito & Vector Control District reports mosquitoes from two locations in Contra Costa County have tested positive for West Nile virus. 
The infected mosquitoes were caught in traps in Discovery Bay and an agricultural area east of Brentwood. The District uses this information to direct prevention and control efforts within the vicinity.  
The confirmation of infected mosquitoes comes less than one week after the District confirmed chickens tested positive for antibodies against West Nile virus near Knightsen.  

Orlando scientists report cancer-killing potential of Zika virus in early study

From the Orlando Sentinel
July 26, 2018

Dr. Kenneth Alexander was driving home one day last year when he thought of the idea: what if the Zika virus could be used to kill a childhood cancer called neuroblastoma?

The Zika outbreak was in its third year and scientists had learned that the virus damages the nervous systems of unborn babies by destroying the developing nerve cells.

Those developing nerve cells also make up neuroblastomas.

So, Alexander, chief of the Division of Infectious Diseases at Nemours Children’s Hospital, started brainstorming with a surgeon colleague and brought on board Dr. Griffith Parks, a University of Central Florida scientist who has been studying Zika.

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Zika may be sexually transmissible for shorter than previously thought

From Healio
July 25, 2018

The period during which Zika virus can be sexually transmitted is shorter than was estimated in the earliest studies published after the epidemic, according to results of a living systematic review published in PLOS Medicine.

“Zika virus (ZIKV) can be transmitted between humans through sexual contact, although it is most commonly transmitted by infected Aedes spp. mosquitoes,” researchers in Switzerland and the United States wrote. “Sexual transmission of ZIKV has important implications for public health, for people living in endemic regions, and sexual partners of travelers returning to nonendemic regions from endemic regions because ZIKV infection during pregnancy can cause congenital infection of the fetus and because ZIKV infection can trigger the immune-mediated neurological condition Guillain-Barré syndrome.”

A CDC spokeswoman told Infectious Disease News in April that the agency would re-evaluate its guidance for the prevention of sexual transmission of Zika virus based on findings published in The New England Journal of Medicine that showed that men can sexually transmit the virus for only a short period of time — perhaps just a few weeks after they become ill. Asked for an update, the spokeswoman said she was not aware of any changes to the guidance.

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Treatment scheduled Thursday in Sunnyvale and Santa Clara to eradicate West Nile Virus-infected mosquitoes

From The Mercury News
July 25, 2018

Parts of Sunnyvale and Santa Clara will be sprayed late Thursday night as part of a mosquito eradication effort to protect against the spread of West Nile virus.

The Santa Clara County Vector Control District scheduled the 11 p.m. truck-mounted mosquito control treatment after determining that a sampling of adult mosquitoes near Sunnyvale and Santa Clara had tested positive for the virus.

West Nile virus is transmitted to humans by mosquitoes and can cause mild to severe flu-like symptoms, such as fever, headache and body ache. In severe cases, the virus can cause significant neurological damage and even death, according to the district.

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Tickborne diseases are likely to increase, say NIH officials

The incidence of tickborne infections in the United States has risen significantly within the past decade. It is imperative, therefore, that public health officials and scientists build a robust understanding of pathogenesis, design improved diagnostics, and develop preventive vaccines, according to a new commentary in the New England Journal of Medicine from leading scientists at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

Bacteria cause most tickborne diseases in the United States, with Lyme disease representing the majority (82 percent) of reported cases. The spirochete Borrelia burgdorferi is the primary cause of Lyme disease in North America; it is carried by hard-bodied ticks that then feed on smaller mammals, such as white-footed mice, and larger animals, such as white-tailed deer. Although there are likely many factors contributing to increased Lyme disease incidence in the U.S., greater tick densities and their expanding geographical range have played a key role, the authors write. For example, the Ixodes scapularis tick, which is the primary source of Lyme disease in the northeastern U.S., had been detected in nearly 50 percent more counties by 2015 than was previously reported in 1996. Although most cases of Lyme disease are successfully treated with antibiotics, 10 to 20 percent of patients report lingering symptoms after effective antimicrobial therapy. Scientists need to better understand this lingering morbidity, note the authors.

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Press Release From Coachella Valley MVCD
July 25, 2018

Mosquito-borne virus activity intensifies in the East Valley, truck-mounted control planned in Mecca.

INDIO, CA, JULY 25, 2018: The Coachella Valley Mosquito and Vector Control District detected West Nile virus (WNV) activity for the first time in Thermal in 2018 and continued activity of St. Louis encephalitis virus (SLEV) in Mecca. Mosquitoes trapped in downtown Mecca tested positive for SLEV, the first mosquito-borne virus activity detected in an East Valley residential community this year.

In Mecca, mosquitoes collected from a trap near Lincoln Street and 65th Avenue and from a trap near Colfax Street and 72nd Avenue tested positive for SLEV. The mosquitoes that tested positive for WNV came from a trap in Thermal near Pierce Street and Avenue 70.

This brings the number of WNV-positive mosquito samples to 11 and the number of SLEVpositive mosquito samples to 11 for 2018. Last year at this time the District had detected 69 WNV-positive mosquito samples and no SLEV-positive mosquito samples. All mosquitoes were tested at the Coachella Valley Mosquito and Vector Control District laboratory.

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Press Release from San Joaquin County MVCD
July 23, 2018

(STOCKTON, CA) – Although San Joaquin County experienced a cool spring with low mosquito populations, hot weather has caused a significant rise in mosquitoes. Subsequently, San Joaquin County Mosquito and Vector Control District’s (District) surveillance and disease testing laboratory continues to report high West Nile virus (WNV) infection rates in collected mosquitoes. “The District is taking an aggressive approach to reducing mosquito populations; however with high infection rates in collected mosquito samples, we are notifying the public to take precautions, said Ed Lucchesi, Manager with the District. “Using EPA registered repellents containing DEET, Picaridin, IR3535, or Oil of Lemon Eucalyptus are recommended to prevent mosquito bites and reduce the risk of mosquito-borne disease,” said Lucchesi.

Other prevention tips include eliminating standing water and using mosquitofish in water troughs, neglected pools, and water features. Avoid being outdoors if mosquitoes are present. When appropriate, loose fitting long sleeves and pants help prevent mosquito bites. To reduce mosquitoes indoors, maintain good tight fitting screens on windows and doors.

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Here’s what you need to know about West Nile aerial spraying in Elk Grove, Pocket area

From The Sacramento Bee
July 23, 2018

In an effort to target and kill mosquito populations, aerial spraying will take place Monday and Tuesday nights in areas with intense West Nile Virus activity within the Sacramento region.

The Sacramento-Yolo Mosquito and Vector Control District has planned for spraying to begin at 8 p.m. both nights.

Luz Robles, a spokesperson for the district, answered questions from The Bee about the spraying.

Here’s what you need to know.

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Mosquito control district finds more West Nile virus

From the Tracy Press
July 23, 2018

A jump in the number of mosquitoes found with West Nile virus in San Joaquin County has brought new warnings from the San Joaquin County Mosquito & Vector Control District as the San Joaquin Valley heats up.

Aaron Devencenzi, a public information officer for the vector control district, said the number of mosquito samples testing positive for West Nile virus had increased by more than 10 times within three weeks.

“When we were looking at the week of June 24 through the 30th, we only had eight mosquito samples positive for West Nile virus, and as of now — we collected last week — we’re at 89 samples that are positive, so we have had substantial amount showing positive in that three-week period,” Devencenzi said.

Devencenzi said that the rise in temperatures was the likely cause of the increased mosquito numbers this summer.

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City may have contributed to West Nile virus outbreak in Pocket area, officials say

From The Sacramento Bee
July 20, 2018

As concerns grow over reports of intense West Nile virus activity in the Sacramento region, the city of Sacramento Department of Utilities may have unintentionally accelerated a localized increase of West Nile activity in the Pocket area.

The Sacramento-Yolo Mosquito and Vector Control District confirmed that a disruption in water flow from the Pocket Canal to the Sacramento River caused mosquitoes to proliferate in the area. Efforts by the city to apply an algaecide treatment to the Pocket Canal caused the water disruption.

As a result, water backed up into drain inlets in residential areas of the Pocket. The stagnant water within the basins acted as an ideal breeding ground for mosquitoes during West Nile virus season.

With high activity in the area, aerial sprays for West Nile virus could occur next week, the vector control district announced Wednesday. The district is expected to decide Friday whether to spray over Pocket/Greenhaven, south Sacramento and Elk Grove.

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Dangerous mosquito-borne virus detected at Buena Vista Lake

From KGET.com
July 20, 2018

BUENA VISTA LAKE, Calif. – A dangerous mosquito-borne virus has been detected at Buena Vista Lake, marking its first appearance in Kern County this season, according to the West Side Mosquito & Vector Control District. 

St. Louis Encephalitis Virus was detected in mosquito samples taken from a source near the lake, the district said. 

SLEV can cause “fever, headache, dizziness, nausea, and malaise,” as well as coma in extreme cases, according to the Centers for Disease Control and Prevention. 

The overall fatality rate of SLEV is between five and 15 percent. 

Other symptoms include “stiff neck, confusion, disorientation” and “tremors and unsteadiness,” the CDC says. 

Technicians are “actively treating and monitoring the area” of Buena Vista Lake, the district said.  

The district is urging the public to take precautions against mosquitos while engaging in outdoor activities, and says peak mosquito activity occurs during dawn and dusk. 

People should use insect repellant containing DEET, picaridin, oil of lemon eucalyptus, or IR3435, the district said. 

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First cases of West Nile virus found in Shasta County

July 19, 2018

The first two positive results for West Nile virus have been found in mosquito samples gathered in the northern Anderson and central Redding areas according to the Shasta Mosquito and Vector Control District

The district is asking people to drain standing water in an effort to limit mosquito breeding areas. 

“Despite knowing that West Nile virus will be in Shasta County at some level for the foreseeable future, it is important that residents take these indicators seriously and do what they can to prevent mosquito bites,” Peter Bonkrude, District Manager of the Shasta Mosquito and Vector Control District said in a statement.

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S.J. County confirms first human case of 2018 West Nile virus

From Lodi News
July 18, 2018

San Joaquin County has seen its first human case of West Nile virus for 2018, according to Public Health Services.

A 51-year-old man living in Stockton was the first to be diagnosed this year and reportedly developed a mild form of the infection, and recovered fully without medical intervention.

Dr. Gordon Arakawa, San Joaquin County assistant public health officer, said the infected man recalls being bitten by mosquitoes recently, but since he works outdoors throughout the Central Valley, he does not know whether or not he was bitten within San Joaquin County.

The majority of people who become infected by the virus do not report any symptoms, Arakawa said.

If symptoms do develop, they usually show 3 to 14 days after being bitten by an infected mosquito, Arakawa said.

Roughly 19 percent of people may develop symptoms such as headaches, fevers, body aches and skin rashes.

However, one percent can develop a serious neurologic illness characterized by severe headaches, very high fevers, neck stiffness, disorientation, convulsions and even paralysis, Arakawa said.

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Mosquitoes pose a triple threat as a vector of three viruses

From the Sun-Gazette
July 18, 2018

VISALIA – Residents of Visalia beware of the dangers lurking around standing water and other mosquito breeding grounds. The Tulare County Health & Human Services and the Delta Vector Control District are asking people to be vigilant against mosquito bites. According to the Delta Vector Control District, sampling from local mosquitoes has detected the St. Louis Encephalitis Virus (SLEV) and West Nile Virus (WNV). And while it has yet to be detected in Tulare County, mosquitoes also carry the Zika Virus.

Any container with as little as a few inches of water standing for more than three days is a potential mosquito breeding source. General areas affected by the virus are viewable on the Delta Vector Control District home page, www.deltavcd.com/ by clicking on the tab “Current Mosquito Collections.”

Of particular concern are these three illnesses that can occur after being bitten by a mosquito:

  • West Nile Virus (WNV) – Although most individuals will experience no effects from WNV, symptoms include fever, headache, body aches, skin rash, and swollen lymph nodes, while more severe symptoms include disorientation, coma, tremors, convulsions, and paralysis.
  • St. Louis Encephalitis Virus (SLEV) – SLEV is transmitted through the bite of an infected mosquito, and most people have no symptoms or only mild, flu-like illness. However, especially in the elderly, SLEV can cause serious illness that affects the central nervous system.
  • Zika Virus – Zika is a public health concern to individuals, especially pregnant women, traveling to areas where the virus is prevalent. It is spread through the bite of an infected mosquito or through unprotected sex with an infected partner. The mosquitoes that carry the Zika virus have been detected in an increasing number throughout California. The most concerning issue with the virus is that it can have detrimental effects on a pregnant woman’s developing baby.

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West Nile Virus Found In Mosquitoes In Santee

From the Santee Patch
July 18, 2018

SAN DIEGO COUNTY, CA – West Nile virus made its first appearance of the summer in San Diego County this week when a batch of mosquitoes in Santee tested positive for the viral infection, county officials announced Wednesday.

West Nile virus mainly affects birds, but it can be transmitted to humans by mosquitoes that feed off an infected animal and then bite people.

Officials said West Nile virus has been present in San Diego County since 2003. However, no people or birds — the main carriers of West Nile virus — have tested positive for the virus in the county this year.

Only about 20 percent of people who get infected with West Nile virus suffer any symptoms, though it can be deadly in rare cases. Symptoms are typically mild, including headache, fever, nausea, fatigue, skin rash or swollen glands.

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St. Louis Encephalitis Detected in More Eastern Coachella Valley Mosquitoes

From MyNewsLA.com
July 18, 2018

More mosquitoes testing positive for St. Louis encephalitis have been located in the Eastern Coachella Valley, local vector control officials reported Wednesday.

Mosquitoes testing positive for the virus have been found in Mecca and North Shore, according to the Coachella Valley Mosquito and Vector Control District.

Officials say that the positive samples were found in traps earlier this month near Grant Street and Avenue 71, as well as Johnson Street, near Avenue 70 in Mecca. In North Shore, officials collected positive samples from a trap near Cleveland Street and Avenue 72.

By this date last year, no positive St. Louis encephalitis samples had been found. This year, eight infected mosquitoes have been located in the Coachella Valley, all in Mecca and North Shore, according to the CVMVCD.

Helicopter spraying will be conducted in the evening hours, weather permitting from Monday to Wednesday in Mecca and North Shore.

The discovery also follows recent detections of West Nile virus in nine mosquitoes found in Palm Desert and Indian Wells, which led to increased mosquito spraying and trapping there.

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It’s supposed to be a ‘mild’ year in Orange County for West Nile virus, but you should still take precautions

From The Orange County Register
July 18, 2018

Though the Orange County Mosquito and Vector Control District expects 2018 to be a “mild” year for West Nile virus, officials from the public health agency are nonetheless advising residents to do what they can to avoid getting bitten.

Orange County residents are encouraged to use mosquito spray; close windows and doors unless screened; and wear light-colored long shirts and pants as darker colors attract mosquitoes.

West Nile virus is transmitted to humans and animals by infected mosquitoes that feed on dead birds carrying the virus. According to the World Health Organization, about 80 percent of infected people will be asymptomatic, but some who contract the viral infection may experience flu-like symptoms such as headaches, fever, or joint and muscle aches.

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West Nile Virus Found In Mosquitoes In East County

From La Mesa Patch
July 18, 2018

EAST COUNTY, CA – West Nile virus made its first appearance of the summer in San Diego County this week when a batch of mosquitoes in Santee tested positive for the viral infection, county officials announced Wednesday.

West Nile virus mainly affects birds, but it can be transmitted to humans by mosquitoes that feed off an infected animal and then bite people.

Officials said West Nile virus has been present in San Diego County since 2003. However, no people or birds — the main carriers of West Nile virus — have tested positive for the virus in the county this year.

Only about 20 percent of people who get infected with West Nile virus suffer any symptoms, though it can be deadly in rare cases. Symptoms are typically mild, including headache, fever, nausea, fatigue, skin rash or swollen glands.

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West Nile virus activity intensifies across Sacramento Valley

From the Daily Democrat
July 17, 2018

Elk Grove >> The Sacramento-Yolo Mosquito and Vector Control District continues to closely monitor areas throughout Sacramento County where West Nile virus activity has intensified over the last few weeks.

District officials reported that in Sacramento County, 95 mosquito samples and 49 dead birds have tested positive for West Nile virus to date and that Yolo County had four mosquito samples and four dead birds reported.

As a result, spraying for mosquitoes has been increased slightly. Areas of concern include Elk Grove as well as the Pocket and neighborhoods south of Fruitridge Road in Sacramento.

“We are seeing high levels of West Nile virus activity, we are very concerned and are evaluating aerial spraying,” said Gary Goodman district manager. Lab results received today showed an increase to the already widespread activity. In response to the ongoing West Nile virus activity, the District has intensified ground mosquito control treatments.

Field staff are working extended hours to inspect and treat many area parks, trails, creeks, drainage canals and other riparian corridors where mosquito populations are high.

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Zika and health cuts blamed for rise in baby death rates in Brazil

From The Guardian
July 17, 2018

The number of children dying in their first year of life has risen in Brazil for the first time since 1990.

It’s a worrying setback for a country once seen as a model of poverty reduction.

The infant mortality rate rose by nearly 5% between 2015 and 2016, an increase health officials and specialists have blamed on the outbreak of the Zika virus that year, as well as cuts to health services prompted by an economic crisis from which Brazil is struggling to recover.

Fatima Marinho, director of the non-communicable diseases department and information and analysis at the health ministry, said she expects the 2017 figures to exceed the 2015 levels.

“We are going backwards, not forwards,” Marinho said. “We cannot go on with the situation. Or we lose everything we have gained in 15 years.”

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First West Nile Positive Mosquitoes Found – Panorama City

From SCVNews.com
July 16, 2018

The Greater Los Angeles County Vector Control District confirmed West Nile virus in a sample of mosquitoes collected from Panorama City (zip code 91402), the first confirmation of WNV activity in the district’s service area this year.

While this is only the first confirmation, it should serve as a strong reminder that mosquitoes throughout much of Los Angeles County are active, may be carrying West Nile virus, and can infect people if they bite.

Last year alone, the District collected 394 samples of mosquitoes confirmed positive for WNV.

“We find West Nile Virus widespread throughout the southland every year,” said Susanne Kluh, director of scientific technical services. “This is an annual risk and one residents must be aware of and take actions to prevent. We can’t do this alone.”

Many mosquito repellents are available to prevent bites, but they do not all work equally well. The Centers for Disease Control recommend products with the active ingredients DEET, Picaridin, IR3535, or oil of lemon eucalyptus as being safe and effective against mosquitoes that can transmit disease when used according to the labels. Wearing loose-fitting long sleeves and pants can also help deter bites.

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Researchers to target mosquito egg production to curtail disease

From Phys.org
July 14, 2018

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. 

The research project, titled “Molecular Basis of Ecdysteroid Action in the Mosquito,” is expected to help Raikhel, Roy, and others in Raikhel’s lab identify targets that can block the reproduction of female mosquitoes, thereby resulting in significant declines in mosquito populations and the dangerous diseases they transmit. 

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Garlic? Bananas? Citronella? Debunking mosquito repellent myths

From ABC10
July 13, 2018

As West Nile Virus activity surges in Sacramento County, it’s more important than ever to use mosquito repellent.

But which one should you use? It turns out, there’s a lot of myths around ways to repel the biting pests.

“A lot of people think that if you eat a lot of garlic, if you eat a lot of bananas, if you maybe put a bounce sheet in your pocket, that all of those things will keep mosquitoes away,” Luz Maria Robles with the Sacramento-Yolo Mosquito and Vector Control District explained.

So, do they work? Sorry, but according to Robles, no.

Another common remedy is citronella — an herbal oil found in lemongrass. Citronella candles are advertised as a natural alternative to repellents like DEET. But, although it’s natural, it doesn’t really work. A study in the Journal of Insect Science found it has no affect at all on banishing the bugs.

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From Action News Now
July 12, 2018

Butte County Mosquito and Vector Control announced Thursday that several mosquitos in Butte County are plagued with West Nile and the virus is now active in Butte County.

Groups of positive mosquitoes, known as a “mosquito pool,” collected in the areas of Honcut, Palermo, and Dayton have tested positive with the West Nile virus.

With increasing mosquito populations and the detection of West Nile virus within Butte County, the Butte County Mosquito and Vector Control District urges residents to take all precautions necessary to drain any and all unneeded standing water, report any suspected mosquito-breeding sites and protect themselves from the bites of mosquitoes.

This is the first positive indicator of West Nile Virus in the county for 2018. West Nile Virus is active throughout the State of California.

“It’s imperative that county residents be aware that West Nile Virus is active and to avoid mosquito bites by whatever means necessary,” said Matthew Ball, District Manager for the Butte County Mosquito and Vector Control District. “Residents are urged to do their part to prevent mosquitoes from breeding by inspecting and eliminating all standing water from their properties.”

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