Mosquitoes require stagnant pools of water to breed. Enter NAP... The artificial habitats created and supported by
NAP have resulted in the propagation of stagnant pools of water, standing water in the stumps of trees that have been cut
down, abandoned tires, and brush piles. These sites are all ideal breeding grounds
for disease-borne mosquitoes. Evidence of such can be seen at such sites as Glen Park (near the children’s day care
Known the world over for its bloodsucking bite, the mosquito is probably
one of the most unpopular creatures known to man. In fact, the mosquito inspired American inventor Thomas Alva Edison to create
the electric bug zapper. For centuries, people have tried to kill mosquitoes, only to find them flourishing in spite of their
efforts. Recognizing the inherent public health issues surrounding the mosquito, municipalities are spending millions of taxpayer
dollars forming mosquito abatement districts in an effort to eradicate this menace.
What makes the mosquito so unpopular is the disease and pestilence they
carry and pass on to the victims of their bite. The mosquito has caused more human suffering than any other organism known
to mankind. One million people die from mosquito-borne diseases every year, and about half of the world’s population
is at risk. World history is replete with reports of the life threatening diseases transmitted by mosquitoes including West Nile Virus, Eastern Equine Encephalitis, Malaria
the United States there are hundreds of millions of cases of mosquito-borne
diseases," says Dawn Wesson, associate professor at the Tulane School of Public Health in Louisiana. "It's just huge in terms of the magnitude."
Last year, the U.S. Centers for Disease Control
and Prevention recorded 2,470 cases of West Nile virus and 88 deaths from West Nile virus in the United States.
Those numbers are dwarfed by the statistics
associated with another mosquito-borne disease, malaria, which infects an estimated 300 million to 500 million people each
year. In Africa, malaria kills one child every 30 seconds, according to the CDC. Malaria was eradicated in the United States
in the 1950s. Still, about 1,300 malaria cases are reported each year, the majority of the patients being travelers and immigrants,
according to the CDC.
Dengue fever afflicts tens of millions per
year globally, while the more violent form, Dengue hemorrhagic fever, affects hundreds of thousands annually. Japanese encephalitis,
found mainly in Asia, causes 30,000 to 50,000 people to become ill each year, while yellow fever claims an estimated 30,000
lives annually in South America and Africa.
Other mosquito-transmitted diseases on the
U.S. radar include eastern equine encephalitis
and St. Louis encephalitis. Eastern equine encephalitis
has a much higher fatality rate than West Nile virus, but on average infects only four people
a year. St. Louis encephalitis, while not as dangerous, is diagnosed in an average of 128 Americans a year.
But experts say West Nile virus is
the biggest mosquito-borne threat facing Americans, just six years after being detected in the United States. The Sacramento Bee reports as of September 1, 2005, California has seen a total of 416 West Nile cases, eight of which have
resulted in deaths. On August 15, 2005, San Francisco health officials confirmed the City's first human case of West
In fact, San Francisco Recreation and Park Department acknowledges the mosquito
problem in their “System Wide Management
Actions and Practices” document pertaining to significant natural areas. Section
5, page 22 of that document states:
“First detected in the United States
in 1999, West Nile virus (WNV) is a mosquito-borne
disease that is common in Africa, west Asia and the Middle East. In 2004, there were
a total of 829 WNV human infections, from 23 counties in California.
West Nile virus activity has been detected in all counties, but there have been no cases reported from San Francisco (DHS 2005). Although it can be fatal to birds (and even humans), most of the
people infected with WNV do not exhibit any symptoms. The San Francisco Health Department currently participates in the statewide
IPM program targeting WNV. In Natural Areas, two types of BMPs [Best Management Practices] are recommended:
1. Staff should be provided education regarding the most effective way to avoid
contracting WNV, which is to not get bitten by mosquitoes. Clothing such as long
pants, long-sleeved shirts, and application of a mosquito repellent may all be helpful in
this regard. Volunteers and site stewards working with the program should also be
2. Some Natural Areas contain small water features such as abandoned tires and other
refuse that holds water. These features could provide breeding habitat for mosquitoes.
At times it may be feasible to remove the water from these areas or to treat the features
with BT (Bacillus thuringiensis israeliensis), a safe and ready to
use biocontrol treatment
for mosquitoes. In other cases, removal of water cannot occur without damaging a sensitive resource.”
Click here to view a copy of the complete SFRPD document.