West Nile Virus is not present in the City.
(Barstow)– On Monday, September 19, 2011, the San Bernardino County
Department of Public Health reported that a 57 year old City of Barstow resident was
infected with West Nile Virus on or around August 29, 2011. After learning of the
situation, the City began coordinating with the County to respond to the event.
However, after further research and review, it has been determined that the infectious
mosquito bite which transmitted the disease took place in the City of Fontana. This
means that the mosquitoes which caused the West Nile Virus infection did not come
from the Barstow area.
As soon as information became available this week indicating that a potential human
transmission of West Nile Virus occurred in the Barstow area, the City coordinated with
San Bernardino County to proactively conduct surveillance and mosquito abatement
activities within City limits. This week, mosquito trapping occurred in town and the
County Vector Control Agency notified the City tonight that all tests have come back
negative for West Nile Virus. It is also important to note that San Bernardino County
Public Health authorities are of the opinion that the mosquitoes in Barstow are not
transmitting the West Nile Virus.
Some frequently asked questions and corresponding answers regarding the West Nile
Virus include the following:
What is West Nile Virus?
West Nile virus (WNV) is a mosquito-borne disease that was originally found in Africa.
In 1999, it was detected in the eastern United States; since then the virus has spread
throughout the United States and is well established in most states, including California.
How do people get WNV?
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.
How soon do infected people get sick?
People typically develop symptoms from 3 to14 days after they are bitten by an infected
What are the symptoms of WNV?
WNV affects the central nervous system. However, symptoms vary:
No Symptoms in Most People. Approximately 80 percent of people (about 4 out
of 5) who are infected with WNV will not show any symptoms.
Milder Symptoms in Some People. Up to 20 percent (about 1 in 5) of the people
who become infected will display symptoms which can include fever, headache,
body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin
rash on the chest, stomach and back. Symptoms generally last for just a few
days, although even previously healthy people have been sick for several weeks.
Serious Symptoms in a Few People. Less than one percent (about 1 in 150
people) of individuals infected with WNV will develop severe illness. The severe
symptoms can include high fever, headache, neck stiffness, stupor,
disorientation, coma, tremors, convulsions, muscle weakness, vision loss,
numbness and paralysis. These symptoms may last several weeks, and
neurological effects may be permanent. WN virus infection can be fatal.
Who is at greatest risk of getting severely ill from WNV?
People over the age of 50 have a higher chance of getting sick and are more likely to
develop serious symptoms when infected with West Nile virus. Being outside,
especially at dawn or at dusk, increases your risk of being bitten by an infected
mosquito. Take precautions to avoid mosquito bites if you spend a lot of time outside,
either working or playing. Risk of transmission through medical procedures is very low.
All donated blood is checked for West Nile Virus before being used. The risk of getting
WNV though blood transfusions and organ transplants is very small, and should not
prevent people who need surgery from having it.
How is WNV infection treated?
There is no specific treatment for WNV infection. In cases with milder symptoms, people
experience fever and aches that pass on their own. In more severe cases, people may
need to go to the hospital where they can receive supportive care including intravenous
fluids, help with breathing, and nursing care.
What should I do if I think I have WNV?
Milder WNV illness improves without treatment, and people do not necessarily need to
seek medical attention for this infection, though they may choose to do so. If you
develop symptoms of severe WNV illness, such as unusually severe headaches or
confusion, seek medical attention immediately. Pregnant women and nursing mothers
are encouraged to talk to their doctor if they develop symptoms that could be WNV.
If you have had WNV, are you immune to further infections?
It is thought that once a person has recovered from WNV, they are immune for life to
future infections with WNV. This immunity may decrease over time or with health
conditions that compromise the immune system.
Can animals get sick from WNV?
An infected mosquito can bite any animal, but not all animals will become sick. The
disease most often affects birds but may occasionally cause disease in other animals.
Wild birds serve as the main source of virus for mosquitoes. Infection has been reported
in more than 225 bird species. Although many birds that are infected with WNV will not
appear ill, WNV infection can cause serious illness and death in some birds. The most
severe illnesses are seen among the corvid birds , which include crows, jays, ravens,
Outside of birds, do other animals get sick from WNV?
Tree squirrels with West Nile virus can develop neurological symptoms such as
uncoordinated movement, paralysis, shaking, or circling and may die.
Like people, most horses bitten by mosquitoes will not become sick with WNV.
However, of those that do, clinical signs may include stumbling, circling, hind leg
weakness, inability to stand, muscle tremors, and death. A vaccine to prevent West Nile
virus is available for horses and horse-owners should consult with a veterinarian about
WNV vaccine and other vaccines against mosquito-borne viruses, such as western
equine encephalitis. For more information on West Nile Virus and horses, please visit
the California Department of Food and Agriculture website at http://www.cdfa.ca.gov.
Dogs and cats can be exposed to WNV in the same way as humans. However, these
animals are very resistant to WNV and rarely become ill. Concerned pet owners should
consult with a veterinarian.
How do I protect myself from exposure to mosquito bites / WNV?
WNV Campaign promotes the following are the most effective ways for individuals to
prevent exposure to mosquito bites and WNV:
DEET – Apply insect repellent containing DEET, picaradin, oil of lemon
eucalyptus or IR 3535 according to label instructions. Repellents keep the
mosquitoes from biting you. DEET can be used safely on infants and children 2
months of age and older.
DRESS – Wear clothing that reduces the risk of skin exposure.
CONTINUED – How do I protect myself from exposure to mosquito bites / WNV?
DOORS – Make sure doors and windows have tight-fitting screens. Repair or
replace screens that have tears or holes to prevent mosquitoes from entering
DAWN AND DUSK – Mosquitoes that carry WNV bite in the early morning and
evening so it is important to wear repellent at this time.
DRAIN or DUMP – Mosquitoes lay their eggs on standing water. Eliminate all
sources of standing water on your property, including flower pots, old car tires,
rain gutters and pet bowls. If you have a pond, use mosquito fish or
commercially available products to eliminate mosquito larvae.
Are there any other tips / information that I need to know about WNV?
Report any “green pools” or pools of standing water to the City of Barstow’s Code
Enforcement Division at (760) 255-5190.
The following are websites where you can find more information about the
symptoms of West Nile Virus and other ways to prevent exposure:
The City has pamphlets with information at City Hall available as well as our
website at www.barstowca.org for updates on the WNV in Barstow.