West Nile Virus

Question 1

West Nile virus is in the _______ family, and causes ______ and ______

Answer 1

Flavivirus; encephalitis; myelitis

Question 2

West Nile is _____, and the equine mortality rate is __ - __% while human mortality is __ - __&

Answer 2

Zoonotic; 30-40; 10-15

Question 3

Those who are highly susceptible to West Nile, in both horses and humans, include…

Answer 3

• the old
• the young
• the immunocompromized

Question 4

The principle carries of West Nile are _____, particularly _________

Answer 4

Birds; crows and bluejays (but 110 bird species are known to carry it)

Question 5

The West Nile vector is _______, particularly the _____ species, of which there are only __, some of which only feed on birds. The others breed near _______ and are known to ______

Answer 5

Mosquitoes; culex; 6; humans and horses; bite viciously

Question 6

The West Nile virus is carried in the mosquitoes’ ______ and is injected into the _______ when they feed

Answer 6

Salivary glands; blood stream

Question 7

The West Nile virus is small enough to pass through the _________ barrier, infecting the ______ and causing Inflammation

Answer 7

Blood brain barrier; brain

Question 8

There is no documented cases of West Nile being transmitted between ______ or ______

Answer 8

Horse-to-horse; horse-to-human

Question 9

Horses with West Nile are only infectious for _____

Answer 9

2-4 days

Question 10

Most horses that develop clinical signs of West Nile have not been ______, or have only had ______

Answer 10

Vaccinated; one dose of the vaccine

Question 11

West Nile symptoms include…

Answer 11

• asymmetric incoordination (ataxia)
• mildly depressed and apprehensive
• fine and course muscle twitching in neck and muzzle
• hypersensitivity to touch/sound
• changes in mental capability
• propulsive walking/pushing forward

Question 12

Horses with West Nile can go from _____ to _____ to _____ in a matter of minutes

Answer 12

Hypersensitive; drowsy; unresponsive

Question 13

To diagnose West Nile, ______ tests like ______ should be run, or a ____ sample can be taken from ____ horses

Answer 13

Blood serum; MAC ELISA and WNV-MAC; brain tissue; dead

Question 14

To treat West Nile, supportive therapy like ______ and _____ should be given, plus lots of ____

Answer 14

Anti-inflammatory medication; acepromazine (to relieve anxiety); rest

Question 15

A large majority of the horses with West Nile virus ____, but some may have _____. It can take a _____ or more to recover, but effects in most cases are not ______.

Answer 15

Recover; prolonged weakness; month; permanent

Question 16

To prevent West Nile, you should…

Answer 16

• vaccinate
• reduce mosquito breeding grounds (no standing water, pesticides, keep grass short)