West Nile Virus is a mosquito-borne virus that originated in
Africa. It first appeared in the United States in 1999 and it
moved West until it reached California in 2003. It is present
throughout the year, although illness is often associated with
peaks during hot summer months.
Zika virus is a mosquito-borne virus that can make humans
How can I get Zika virus?
Zika virus is transmitted through the bite of an infected
mosquito. Mosquitoes infected with Zika virus are currently found
in areas of Africa, Asia, the Pacific Islands, and most recently,
South and Central America and Mexico. Zika may also be
transmitted between partners of any gender during sex, and from a
mother to her unborn baby during pregnancy.
Saint Louis Encephalitis is a virus, related to West Nile virus,
transmitted by the bite of an infected mosquito. Culex tarsalis and to
a lesser extent Culex
pipiens are the mosquito species responsible for
transmitting St. Louis Encephalitis.
Western Equine Encephalitis is a virus transmitted through the
bite of an infected mosquito. The transmission cycle is between
wild birds and mosquitoes. A mosquito will bite a bird infected
with Western Equine Encephalitis and become infected. While
looking for another blood meal, an infected mosquito can infect
an uninfected bird, horse, or human. In past outbreaks, this
disease has caused severe illness and death in horses.
Dog heartworm is a disease caused by a roundworm (Dirofilaria
immitis) which lives in the heart and lungs of dogs.
Heartworm disease has become a serious health problem for dogs
throughout the United States. The disease is transmitted into the
bloodstream of dogs, coyotes, foxes and even cats through the
infective bite of a western treehole
mosquito (Aedes sierrensis). These microscopic
larvae move into the heart and lungs of the animal where they
complete its development.
Chikungunya is a virus transmitted by the bite of an infected
mosquito. It has been found in many parts of the world, including
recently the Caribbean, South and Central America, and North
What are the signs and symptoms of chikungunya?
Symptoms of chikungunya usually begin 3-7 days after infection,
and include fever, severe joint pain, headache, muscle pain,
joint swelling, or rash. Chikungunya is not usually fatal, but
may cause severe pain and discomfort.
Dengue is a virus transmitted by the bite of an infected
mosquito. It has been found in many parts of the world,
including recently the Caribbean, South and Central America, and
What are the signs and symptoms of dengue?
Symptoms of dengue include high fever, severe headache, eye pain,
joint pain, muscle pain, rash, and mild bleeding. A more severe
form of the disease, dengue hemorrhagic fever, has similar
symptoms that are followed by vomiting, severe abdominal pain,
and difficulty breathing.
Yellow fever is a virus transmitted by the bite of an
infected mosquito. It has been found in areas of South America
What are the signs and symptoms of yellow fever?
Symptoms of yellow fever usually begin 3-6 days after
infection, and include fever, chills, severe headache, back pain,
body aches, nausea and vomiting, fatigue, and weakness. These are
rarely followed by a more severe form of yellow fever, including
jaundice, bleeding, high fever, and organ failure.
Malaria is a parasite that is transmitted to humans through the
bite of an infected mosquito. There are four species of malaria
parasites: Plasmodium falciparum, P.
vivax, P. ovale, and P.
malariae. These four species differ in their biology and in
severity of disease.