MOSQUITO- AND BIRD-BORNE DISEASE IS HEADING TO CALIFORNIA.Byline: Staff Writer
After two straight summers of rapid westward movement, the West Nile virus West Nile virus, microorganism and the infection resulting from it, which typically produces no symptoms or a flulike condition. The virus is a flavivirus and is related to a number of viruses that cause encephalitis. is poised to complete its sweep of the continental United States United States territory, including the adjacent territorial waters, located within North America between Canada and Mexico. Also called CONUS. and arrive in California this year. State health officials are bracing for the mobile virus, which is transmitted by mosquitoes and caused 284 deaths nationwide in 2002.
Just in time for mosquito season, blood banks around the country inaugurated a screening test to detect the virus in the first week of July. Around the same time, the first confirmed case of West Nile virus for 2003 was reported in South Carolina South Carolina, state of the SE United States. It is bordered by North Carolina (N), the Atlantic Ocean (SE), and Georgia (SW). Facts and Figures
Area, 31,055 sq mi (80,432 sq km). Pop. (2000) 4,012,012, a 15. . While the virus has not been detected in California this year, West Nile activity is expected to peak in mid-August and September.
``We've had three years to prepare while the rest of the country has been hit,'' said Evelyn Tu, West Nile surveillance coordinator for the California Department of Health Services Department of Health Services may refer to:
Detection efforts include tests on dead birds, mosquito pools and horses. Sentinel chicken flocks placed strategically around the state are checked every two weeks. Human cases of viral encephalitis viral encephalitis Viral meningoencephalitis Neurology, infectious disease A general term for nonpurulent–'aseptic' viral infection of the CNS Etiology Coxsackie A and B–eg, A7, enterovirus 71, herpes simplex, etc Clinical If the viral load is extreme, and aseptic meningitis aseptic meningitis Infectious disease Nonpurulent meningeal inflammation, which is more common in those < age 30 Etiology Viruses, especially Coxsackievirus and echovirus, circumscribed bacterial infections, hemorrhage, neoplasia–eg leukemia and lymphoma, are reported and investigated.
California did have one inexplicable and isolated case of West Nile in Los Angeles County in 2002. So far, the state's stepped-up surveillance efforts have not detected the virus in the mosquito or bird populations. Birds, particularly the crow and jay, have been highly susceptible to West Nile. Mosquitoes typically become carriers by feeding on a bird infected with the virus.
Officials say the likelihood of people falling ill after being bitten by an infected mosquito remains very low - less than 1 percent. In about 20 percent of people infected with the virus, West Nile causes headaches, fever, body aches, nausea, vomiting and a skin rash. Encephalitis encephalitis (ĕnsĕf'əlī`təs), general term used to describe a diffuse inflammation of the brain and spinal cord, usually of viral origin, often transmitted by mosquitoes, in contrast to a bacterial infection of the meninges and meningitis develop in 1 out of 150 cases, according to the Centers for Disease Control and Prevention Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. .
Dry heat helps
California's dry climate isn't considered conducive to mosquito-borne diseases. But climate is not the key factor that concerns Thomas Scott, director of the mosquito research laboratory at the University of California, Davis The University of California, Davis, commonly known as UC Davis, is one of the ten campuses of the University of California, and was established as the University Farm in 1905. . What worries Scott is a particular species of mosquito called Culex Culex /Cu·lex/ (ku´leks) a genus of mosquitoes found throughout the world, many species of which are vectors of disease-producing organisms.
n. tarsalis, common in rural areas of California. In the lab, Culex tarsalis has proven to be proficient at transmitting West Nile to other hosts. Worse, the mosquito also passes on the virus to its offspring.
``They transmit the disease more effectively than any mosquito in North America,'' Scott said. ``If the virus is introduced, it will get into that mosquito. There could be high levels of transmission.''
There are an estimated 200 species of mosquito in the United States and more than 2,500 worldwide, according to the American Mosquito Control Association. More than 30 different mosquito species carrying West Nile have been identified in North America. West Nile's ability to infect numerous species of mosquitoes and birds has fueled its rapid movement, said Dr. Rachel Civen, a medical epidemiologist with the Los Angeles Department of Health Services.
In the United States, West Nile first emerged in New York New York, state, United States
New York, Middle Atlantic state of the United States. It is bordered by Vermont, Massachusetts, Connecticut, and the Atlantic Ocean (E), New Jersey and Pennsylvania (S), Lakes Erie and Ontario and the Canadian province of in 1999. By the end of 2001, the virus had spread as far west as Iowa, Missouri, Arkansas and Louisiana. By the end of 2002, only Oregon, Nevada, Utah and Arizona remained free of the virus.
In 2002, the CDC See Control Data, century date change and Back Orifice.
CDC - Control Data Corporation reported 4,156 confirmed cases of West Nile, including that of a 31-year-old woman from Inglewood. The lone Los Angeles County case stumped investigators. They still do not know how she contracted the virus, Civen said.
``She had no travel history,'' Civen said. ``We did a thorough environmental investigation with mosquito control. We trapped mosquitoes. We even had sentinel chickens on her work route and close to her home. It's a mystery.''
Though the risk of contracting West Nile through blood transfusion blood transfusion, transfer of blood from one person to another, or from one animal to another of the same species. Transfusions are performed to replace a substantial loss of blood and as supportive treatment in certain diseases and blood disorders. is slight, health officials moved to create a screening test that was implemented in early July by blood banks nationwide. Blood banks are now using a nucleic acid nucleic acid, any of a group of organic substances found in the chromosomes of living cells and viruses that play a central role in the storage and replication of hereditary information and in the expression of this information through protein synthesis. amplification test to screen for the virus. After scientists confirmed that 23 cases of West Nile infections could be traced to blood-product transfusions, it became critical to develop and implement the test before the summer mosquito season, said Dr. Steven Kleinman, chairman of the Transfusion Transmitted Diseases Committee for the American Association of Blood Banks.
``We had a target date in mind - and everyone pulled out all the stops,'' Kleinman said.
Previously, clinical tests looked for antibodies formed by the human body. But a person could be infected for 14 to 28 days before producing those antibodies, said Dr. Ross Herron, American Red Cross American Red Cross: see Red Cross. medical director for blood services for Southern California. The nucleic acid amplification test detects the genetic material of the virus. Donated blood already is screened for HIV HIV (Human Immunodeficiency Virus), either of two closely related retroviruses that invade T-helper lymphocytes and are responsible for AIDS. There are two types of HIV: HIV-1 and HIV-2. HIV-1 is responsible for the vast majority of AIDS in the United States. , hepatitis B Hepatitis B Definition
Hepatitis B is a potentially serious form of liver inflammation due to infection by the hepatitis B virus (HBV). It occurs in both rapidly developing (acute) and long-lasting (chronic) forms, and is one of the most common chronic and hepatitis C Hepatitis C Definition
Hepatitis C is a form of liver inflammation that causes primarily a long-lasting (chronic) disease. Acute (newly developed) hepatitis C is rarely observed as the early disease is generally quite mild. , among other diseases.
``The risk of West Nile is low enough, so if transfusion is medically indicated, people shouldn't be worried,'' Kleinman said.
Public health officials also are encouraging Californians to take precautions. When outdoors, wear pants and long-sleeved shirts. Use insect repellent containing DEET. Avoid going outside when mosquitoes are most active - at dawn and dusk. Clear any areas of standing water where mosquitoes can breed. And make sure doors and windows Doors and Windows is a multimedia disk by the Irish band The Cranberries. Track listing
`'Just take the basic preventive measures,'' Tu said. ``There's no need to go out and spend a lot of money. Prevention and precaution are the main things.''
Staff writer Lisa M. Sodders contributed to this report.
Mariko Thompson, (818) 713-3620 mariko.thompson(at)dailynews.com
West Nile facts WHAT IT IS: A flavovirus that has been found in Africa, West Asia, and the Middle East. In the United States, it was first detected in New York in 1999. The virus can infect humans, birds, mosquitoes, horses and some other mammals. HOW IT SPREADS: West Nile is transmitted to people and animals by infected mosquitoes. A mosquito typically becomes infected by feeding on a bird with the virus. SYMPTOMS: Most people infected with West Nile don't experience any symptoms. But for those who do contract signs of the flu-like illness, they may experience fever, headache, nausea, body aches, mild skin rash and swollen lymph nodes. In 1 in 150 cases, patients will develop encephalitis or meningitis. The elderly are at greater risk for developing a severe case of West Nile infection. SURVEILLANCE: The dying off of birds, particularly crows and jays, can be a sign that the West Nile virus has struck. If you come across a dead bird, don't touch it. Report the sighting to the California Department of Health Services at its toll-free number, (877) WNV-BIRD. They will collect the bird and test for West Nile if appropriate. PREVENTION: Public health officials say basic preventive measures will reduce the risk of infection. -- When outdoors, wear pants and long-sleeved shirts. -- Use insect repellent containing DEET. -- Avoid going outside when mosquitoes are most active - at dawn and dusk. -- Clear any areas of standing water where mosquitoes can breed. At least once a week, empty water from flowerpots, bird baths, swimming pool covers, pet bowls and other places where water collects. -- Make sure doors and windows have tight-fitting screens. For more information on West Nile: Los Angeles County Department of Health Services The Los Angeles County Department of Health Services (DHS) in Los Angeles County's department providing public and personal health services to the over 10 million residents in the County. www.lapublichealth.org/acd/VectorWestNile.htm California Department of Health Services www.westnile.ca.gov Centers for Disease Control and Prevention www.cdc.gov/ncidod/dvbid/westnile/index.htm Sources: Centers for Disease Control and Prevention and California Department of Health Services
3 drawings, photo, box
Drawing: (1 -- cover -- color) WEST NILE ON THE WEST COAST California braces itself for the virus (2 -- 3) no caption (mosquitos) Illustrations by Jon Gerung/Staff Artist Photo: Health officials created a screening test for West Nile virus that was implemented earlier this month at blood banks nationwide, including at the Red Cross in Van Nuys. Joe Binoya/Special to the Daily News Box: West Nile facts (see text)