West Nile Virus

[KC]

It's West Nile Virus time again....

California West Nile Virus website:

http://www.westnile.ca.gov/

> From their website

2006

11 dead birds have tested positive for WNV in 2006, from Sacramento, Santa Clara, San Diego, and Orange Counties.

2005

West Nile virus activity was detected in 54/58 California counties in 2005.

Humans

To date in 2005, there have been 935 human WNV infections from 40 counties in California.

101 of the 935 infections were first detected in asymptomatic individuals through screening done at blood banks - 42 later became symptomatic. Eight of the 101 presumptively viremic blood donors did not confirm in follow-up testing, and have been removed from the totals. Four asymptomatic individuals were detected via local public health agencies.

Of the 880 WNV cases with symptoms, 305 were classified as West Nile neuroinvasive disease, 534 were classified as West Nile fever cases, and 41 were of unknown clinical presentation.

There were 19 West Nile virus-related fatalities reported in California in 2005 from Amador, Butte, Fresno, Kings, Madera, Plumas, Riverside, Sacramento, San Bernardino, San Joaquin, Stanislaus, and Tulare counties.

Equines (Horses)

In 2005, 456 horses from 43 counties were infected with WNV. Of the horses with infections, 200 have either died or been euthanized.

Dead Birds

In 2005, 3,046 dead birds from 52 counties tested positive for WNV in California.

The top 4 species affected by WNV are 1) American Crows 2) Western Scrub-Jays 3) Yellow-billed Magpies and 4) Steller's Jays

Mosquito Pools and Sentinel Chickens

In 2005, 1,242 mosquito pools from 29 counties tested positive for WNV.
1,053 chickens from 31 counties tested positive for WNV/SLE ***antibodies (seroconverted) in 2005.

* Horse data is only updated on Fridays

** A mosquito pool is a collection of approximately 50 mosquitoes that are tested together for West Nile virus.

*** WNV and SLE (St. Louis encephalitis) are closely related viruses in the family Flaviviridae and preliminary testing cannot distinguish between these two viruses. Further testing is conducted as needed to determine if the sentinel chickens are antibody positive to WNV or SLE.
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> Also from the website

How is WNV transmitted?


Infected Mosquitoes. Most often, WNV is spread by the bite of an infected mosquito. Mosquitoes are WNV carriers ("vectors") that become infected when they feed on infected birds. Infected mosquitoes can then spread WNV to humans and other animals when they bite.

Transfusions, Transplants, and Mother-to-Child. All donated blood is checked for WNV before being used. The risk of getting WNV through blood transfusions and organ transplants is very small, and should not prevent people who need surgery from having it. Transmission during pregnancy from mother to baby or transmission to an infant via breastfeeding is extremely rare.

Not through touching. WNV is not spread through casual contact such as touching or kissing a person with the virus, or by breathing in the virus.

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Observations:

1) West Nile is a vector borne illness that IS HUMAN TO HUMAN.

2) We saw hundreds of dead crows in our area. They were reported but nobody ever came to pick them up and have them tested. These were official reports from one government agency to another.

3) I read a few posts about H5N1 and migration routes along the Nile River... coincidence or correlation?

3) It is suspected to have arrived on the East Coast of the United States in 1999.

4) Symptoms are very similiar to Chik, Dengue, and other vector borne diseases. All the emphasis has been on avoiding mosquitoes.

5) It has also infected cats, dogs, and squirrels.

[KC]

Re: West Nile Virus

VERY BAD ADVICE

> From the California Website on West Nile Virus

Identify and Report Dead Birds

Information on Reporting Dead Birds

CLICK HERE TO REPORT A DEAD BIRD
or call toll-free:
1-877-WNV-BIRD (1-877-968-2473)
Operators available: 8 am - 5 pm / 7 days a week
After 5 pm, please leave a message

After you have reported a dead bird, you will be contacted if that bird will be picked up for West Nile virus testing. If you have not been contacted within 24 hours of your report, you may safely dispose of the dead bird in your trash. There is no evidence that West Nile virus can be acquired by handling dead birds, but it is best not to handle the dead bird with your bare hands. Use gloves, a shovel, or a plastic bag to place the bird in a trash bag for disposal. Please DO NOT freeze dead birds. West Nile virus is transmitted by mosquitoes, so the best way to protect yourself from West Nile virus is to avoid getting bitten by mosquitoes. Click here for prevention information.

Due to the high volume of reports to the hotline, the California Department of Health Services is unable to respond to each report. However, all of the information received about dead birds is used by public agencies to track where birds are dying. Dead birds are an indicator of West Nile virus activity. This allows the local mosquito and vector control agencies to concentrate mosquito control efforts in those areas. Thank you for your cooperation.

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Advice: Don't pick up dead birds even if a government agency tells you it is safe to do so.

[KC]

Re: West Nile Virus

American Chik?

United States West Nile Virus info:

http://www.cdc.gov/ncidod/dvbid/westnile/

[KC]

Re: West Nile Virus

From 2004.... before the big surge in 2005... hmmm..... Points to ponder....

Virus undercount called likely

WEST NILE: Thousands may not know they've had it, officials say. Bird deaths top 2 million, an expert says.

11:52 PM PDT on Friday, October 15, 2004

By DOUGLAS E. BEEMAN / The Press-Enterprise

WEST NILE VIRUS
County Human cases
San Bernardino 191
Riverside 102
Los Angeles 300
Orange 59
Imperial 1
San Diego 1
California 750

County Deaths
San Bernardino 5
Los Angeles 9
Riverside 2
Orange 3
Tehama 1
California 20

County Equine cases
Riverside 94
San Bernardino 37
California 496
County Equine deaths
Riverside 49
San Bernardino 15
California 210

Numbers as of Friday (2004)

SOURCE: California Department of Health Services, California Department of Food and Agriculture

The number of human West Nile virus cases may be vastly undercounted because most people didn't realize they had been infected, Inland health officials said Friday at a half-day briefing in Riverside.

While the mosquito-borne virus may have gone unnoticed in thousands of people, it has been devastating to bird populations in the state, a UC Riverside scientist said.

"We probably lost something like half a million crows" in California, said Tom Scott, a conservation biologist at UCR. He estimates that as many as 2.5 million birds have died of West Nile virus this year.

"There's never been a virus that's done anything like this in California," Scott said.

Some 750 people in 22 California counties have been infected with the virus this year, according to the latest state figures.

On Friday, state officials announced that an Orange County man has become California's 20th fatality this year from the virus.

The 70-year-old man first became ill Aug. 18, but the state did not confirm the West Nile infection until Wednesday.

The virus also infects horses, which are very vulnerable to it, but there are vaccines available to protect them.

Inland health officials said Friday that the number of reported human infections is lower than they had anticipated. They credited aggressive mosquito control efforts.

Riverside County has confirmed 102 infections, including 42 cases in which people have suffered more serious complications, such as encephalitis and meningitis, said Sarah Mack, the county's chief of health statistics.

The milder form of the disease is called West Nile fever, with symptoms that can include headaches, body aches, a body rash and profound fatigue.

"There probably was more West Nile fever than was reported, but the magnitude is unknown," Mack said.

Historically, about 1 percent of West Nile's victims develop serious complications.

If that is true in California, Mack said, it could equate to more than 4,000 Riverside County infections. (By the same measure, San Bernardino County could have about 5,000 infections.)

The county has reported 49 serious West Nile infections this year, according to county health data.)

Whatever the number, Inland health officials hope fewer people will fall ill next year.

West Nile virus first surfaced in Southern California last year. Infections in other states have peaked in the second year.

"We hope the numbers (of infections) tail off next year," said Dr. Eric Frykman, health officer in San Bernardino County, where 191 infections have been reported. "If this isn't the second year, the numbers will be bigger next year."

Scott, for one, believes next year will see fewer infections. The reason: Many of the birds thought to help the virus amplify in nature have been decimated.

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Comments:

1) Scott was wrong. The death rate among birds and people intensified in 2005 as compared to 2004. The virus continues in 2006. Happy belated new year to anyone studying virology and trends.

[KC]

Re: West Nile Virus

Ventura County added today.

> From California West Nile Virus Site

In 2006:

12 dead birds have tested positive for WNV in 2006, from Orange, Sacramento, San Diego, Santa Clara, and Ventura Counties.

[KC]

Re: West Nile Virus

2005 WNV Map:

[KC]

Re: West Nile Virus

2003 and 2004 WNV Maps:

[KC]

Re: West Nile Virus

From the California West Nile Virus Website:

What is West Nile Virus?
West Nile virus (WNV) is a mosquito-borne disease that is common in Africa, west Asia, the Middle East, and more recently, North America. Human infection with WNV may result in serious illness. Experts believe WNV is established as a seasonal epidemic in North America that flares up in the summer and continues into the fall.

When was WNV first found in the United States?West Nile virus was first detected in the United States in New York in 1999. Since then, WNV has spread to 48 states, and to Canada and Mexico. Last year there were 2,448 human cases of WNV detected in the United States, including 84 deaths. This is much lower than in 2003 when there were more than 10,000 human cases of WNV detected, including 262 deaths.

When was WNV first found in California?
WNV first appeared in California in 2002 with the identification of one human case. In 2003, three human cases occurred in California and WNV activity was detected in six southern California counties. By 2004, WNV activity was observed in all 58 counties in California and 830 human infections were identified. Click Here for a summary of West Nile Virus in California in 2004.

How is WNV detected and monitored in California?
California is well prepared to detect, monitor, and respond to WNV through ongoing collaboration between over 100 public agencies. The California surveillance system includes human and horse case detection and testing of mosquitoes, sentinel chicken flocks, and dead birds for WNV.

[KC]

Alaska on the watch for West Nile Virus

Alaska is on the watch list for West Nile Virus. It will be interesting to see how many birds die from West Nile as compared to H5N1.

http://westnilevirus.nbii.gov/states/alaska.html

Also, a 2002 news article:

http://www.homestead.com/ipmofalaska/files/ADNbugsWNV.html

[KC]

Re: West Nile Virus

From the National Biological Information Infrasturcture (NBII) (http://partners.nbii.gov/portal/server.pt) :

"The West Nile virus (WNV) was first detected in the Western Hemisphere in 1999 and has since rapidly spread across the North Americcan continent into all 48 continental states, seven Canadian provinces, and throughout Mexico. In addition, WNV activity has been detected in Puerto Rico, the Dominican Republic, Jamaica, Guadeloupe and El Salvador."

[KC]

Re: West Nile Virus

From the National Institutes of Health (NIH), U.S. Health and Human Services (HHS) http://www.niaid.nih.gov/factsheets/westnile.htm :

"West Nile virus is an emerging infectious disease that made its first appearance in the United States in 1999. The microbe that causes the infection belongs to a group of disease-causing viruses known as flaviviruses, which are usually spread by ticks or mosquitoes. Other well-known diseases caused by flaviviruses include yellow fever, Japanese encephalitis, dengue, and Saint Louis encephalitis." (My note: Chik also)

... "The first step in the transmission cycle of West Nile virus occurs when a mosquito bites an infected bird or other infected animal. Crows are commonly associated with the virus because they are highly susceptible to infection. Scientists have identified more than 138 bird species that can be infected, and more than 43 mosquito species that can transmit West Nile virus. Although the virus primarily cycles between mosquitoes and birds, infected female mosquitoes also can transmit West Nile virus through their bites to humans and other "incidental hosts" such as horses. With so many susceptible hosts to amplify the virus and so many types of mosquitoes to transmit it, West Nile virus has spread rapidly across the United States."

"West Nile virus was first isolated in Uganda in 1937. Today it is most commonly found in Africa, West Asia, Europe, and the Middle East. In 1999, it was found in the Western Hemisphere for the first time in the New York City area. In early spring 2000, it appeared again in birds and mosquitoes and then spread to other parts of the eastern United States. By 2004, the virus had been found in birds and mosquitoes in every state except Alaska and Hawaii."

... "No specific vaccines or treatments exist for West Nile virus. Faced with a potentially deadly illness spreading quickly across the United States, scientists and public health officials have accelerated research on developing tools to prevent and treat West Nile disease."

... "BASIC RESEARCH"

Complex interactions between the virus, birds and other animals, mosquitoes, and the environment have influenced the pattern of West Nile virus emergence and distribution across the United States. Yet specific factors contributing to the emergence of West Nile virus are poorly understood. Knowledge of these principles is essential in planning strategies to prevent, treat, and control this disease. The goal of NIAID basic research on West Nile virus is to develop the knowledge base to enable the development of medical countermeasures against West Nile virus.

NIAID supports basic research at universities to better understand the infection in animals and humans, the virus itself, and the environmental factors that influence disease emergence. For example, researchers are:

- Determining how the virus replicates and spreads throughout the body in order to develop vaccines and drugs to prevent and treat disease

- Determining which viral proteins contribute to the virus' ability to cause disease

- Investigating how the immune system responds in the most serious form of the disease, West Nile encephalitis

- Studying whether migrating bird populations carry the virus to points in Central and South America. The emergence of West Nile virus in these new areas, which harbor abundant mosquito populations, could set up conditions for a potentially severe epidemic

- Examining the ecology and year-to-year maintenance of mosquito-borne encephalitis viruses and how genetic variation affects spread and virulence of the virus

- Researchers are also working to better understand other insects and ticks that transmit other flaviviruses. Such an understanding will allow improved monitoring and surveillance, and enable development and preliminary testing of strategies to control carriers of the virus.

[KC]

Re: West Nile Virus

Recent News Articles:

http://dailydemocrat.com/news/ci_3739520

http://www.ksby.com/home/headlines/2675861.html

http://cbs2.com/local/local_story_110190228.html

[KC]

Re: West Nile Virus

(Cross Posted into West Nile Virus and Pandemic Chikungunya forums)

2006: From the article posted by Snowy Owl in Pandemic Chik news http://www.flutrackers.com/forum/showthread.php?t=3728 , Aedes and Culex mosquitoes are now known to spread Chik.

Until recently, the primary carrier was considered the be Aedes, in particular Aedes aegypti and Aedes albopictus. The addition of other vector mosquitoes may be critical to the rapid spread and increased virulence of Chik. The increased number of vectors causes a widening of the number and type of reservoir hosts available. It may also cause previously dead end hosts to become reservoir hosts. West Nile Virus in North America has undergone a similar shift.

From the W.H.O. (17 February 2006): ..."Chikungunya, a viral disease, is transmitted to humans by infected mosquitoes, typically Aedes aegypti, although there may be other competent mosquito vectors. The name, chickungunya, comes from the Swahili for stooped walk, reflecting the physique of a person suffering from the disease. The disease has been described in Africa, South-East Asia, southern India and Pakistan. It occurs principally during the rainy season."

"Chikungunya is rarely fatal. Symptoms appear between 4 and 7 days after the patient has been bitten by the infected mosquito. A high fever and headache occur, with significant pains in the joints (ankles, wrists) and can persist for several weeks...."
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From the United States CDC: http://www.cdc.gov/ncidod/dvbid/west...itoSpecies.htm

1999 - Known West Nile Virus Vectors in the United States

Aedes Aedes vexans
Culex Culex pipiens, Culex restuans, Culex salinarius

2006 - Known West Nile Virus Vectors in the United States

Aedes Aedes aegypti, Aedes albopictus, Aedes atlanticus/tormentor, Aedes atropalpus, Aedes canadensis, Aedes cantator, Aedes cinereus, Aedes condolescens, Aedes dorsalis, Aedes dupreei, Aedes fitchii, Aedes fulvus pallens, Aedes grossbecki, Aedes infirmatus, Aedes japonicus, Aedes melanimon, Aedes nigromaculis, Aedes provocans, Aedes sollicitans, Aedes squamiger, Aedes sticticus, Aedes stimulans, Aedes taeniorhynchus, Aedes triseriatus, Aedes trivittatus, Aedes vexans

Anopheles Anopheles atropos, Anopheles barberi, Anopheles crucians/bradleyi, Anopheles franciscanus, Anopheles freeborni, Anopheles hermsi, Anopheles punctipennis, Anopheles quadrimaculatus, Anopheles walkeri

Coquillettidia Coquillettidia perturbans

Culex Culex coronator, Culex erraticus, Culex erythrothorax, Culex nigripalpus, Culex pipiens, Culex quinquefasciatus, Culex restuans, Culex salinarius, Culex stigmatosoma, Culex tarsalis, Culex territans, Culex thriambus

Culiseta Culiseta impatiens, Culiseta inornata, Culiseta melanura, Culiseta morsitans

Deinocerites Deinocerites cancer

Mansonia Mansonia tittilans

Orthopodomyia Orthopodomyia signifera

Psorophora Psorophora ciliata, Psorophora columbiae, Psorophora ferox, Psorophora howardii

Uranotaenia Uranotaenia sapphirina

[AlaskaDenise]

Re: Alaska on the watch for West Nile Virus

.........Also, a 2002 news article:

http://www.homestead.com/ipmofalaska...DNbugsWNV.html

Lobo - the above is a commercial (not news) site, that went out of business (due to lack of demand).

We have not WNV cases yet. The good news is that few of our mosquitos are capable of carrying the virus.

See http://www.alaskatrekker.com/mosquitos.htm

Only two (other sites say 4) of the state's 35 species of mosquitoes have been found to carry the virus in the Lower 48. Chances of the virus taking hold in Alaska are slim, according to wildlife veterinarian Kimberlee Beckmen and Jim Kruse, an insect expert at the University of Alaska Museum. Birds carry the virus, and mosquitoes spread the virus by biting infected birds and injecting it into other birds, people or horses. Alaska has natural limitations for the spread of the virus. The Alaska scientists agree that it's a long shot for the West Nile Virus to establish itself in Alaska. The disease has not made it to higher latitudes of Europe and the two mosquito species that have transmitted the virus most often in the Lower 48 don't live in Alaska. "Until we start getting dead birds up here, there's no reason to worry," Kruse said.
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On a personal note - most news reports are saying......"maybe, but unlikely."

.

[KC]

Re: West Nile Virus

AD,

The only thing stopping WNV from Alaska is B.C. It is in every province of Canada except BC, and in every state in the United States except Hawaii (Hawaii just sent in dead bird samples to be identified).

The updated list of mosquito vectors is from January 06. You will see several of those are cold weather mosquitoes and are found in Alaska. Your Alaska trekkers site may not be utilizing the most recent information on what mosquitoes carry WNV.