West Nile that is… a Flavivirus; West Nile Virus (WNV) is a vector born
disease spread by mosquitoes. Birds are the amplifying hosts, transmitting
the disease to mosquitoes when bitten. The disease is spread when a mosquito
then bites a person. “West Nile virus may also be spread through blood
transfusions and organ transplants.
It is possible for an infected mother to
spread the virus to her child through breast milk” (USNLM, 2012). The American robin
(Turdus migratorius) and the American
crow (Corvus brachyrhynchos) are the
most common carriers of WNV in the Western Hemisphere.
The infected mosquito species vary according to geographical
area; in the US, Culex pipiens
(Eastern US), Culex tarsalis (Midwest
and West), and Culex quinquefasciatus
(Southeast) are the main sources (Hayes, et
al., 2005).
“Thus far in 2012 (as of 8/24/12), 47 states have reported
West Nile virus infections in people, birds, or mosquitoes. A total of 1118
cases of West Nile virus disease in people, including 41 deaths, have been
reported to CDC. Of these, 629 (56%) were classified as neuroinvasive disease (such
as meningitis or encephalitis) and 489 (44%) were classified as
non-neuroinvasive disease” (CDC, 2012).
“The 1118 cases reported thus far in 2012 is the highest
number of West Nile virus disease cases reported to CDC through the third week
in August since West Nile virus was first detected in the United States in
1999. Approximately 75 percent of the cases have been reported from 5 states
(Texas, Mississippi, Louisiana, South Dakota, and Oklahoma) and almost half of
all cases have been reported from Texas)” (CDC, 2012).
Generally, people infected with WNV have positive prognosis;
however severe cases can lead to
Encephalitis or meningitis; and can lead to brain damage and
death. 10% of patients with severe cases
do not survive (USNLM, 2012).
Side note and disease
alert 2:
There is a possible outbreak of another disease…
“A second person has died of a rare, rodent-borne disease after visiting Yosemite National Park earlier this summer and park officials are warning past visitors to be aware of some flu-like aches and symptoms as fears of a possible outbreak mount” (AP, 2012).
This outbreak is a hantavirus .
Taken from the U.S. National library of medicine; "Hantavirus is a life-threatening disease spread to humans by rodents
that has symptoms similar to influenza. Hantavirus is carried by rodents,
especially deer mice. The virus is found in their urine and feces, but it does
not make the animal sick.
It is believed that
humans can get sick with this virus if they come in contact with contaminated
dust from mice nests or droppings. You may come in contact with such dust when
cleaning homes, sheds, or other enclosed areas that have been empty for a long
time".
Hantavirus does not spread between humans.
References:
Center for Disease Control (CDC)
Hayes EB, Komar N, Nasci RS, Montgomery SP, O'Leary DR,
Campbell GL (2005). "Epidemiology and transmission dynamics of West Nile
virus disease". Emerging Infect. Dis. 11 (8): 1167–73
Associated press (AP):
U.S. National Library of medicine http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004457/
Image credit: http://en.wikipedia.org/wiki/File:Aedes_albopictus_2.jpg
No comments:
Post a Comment