We attach here some additional concerns about the spraying, which could
not be included in the original op-ed because of word limitations:
• The issue has been badly sensationalized by officials and the
press. The CDC estimates that of those people who do contract the
virus, 80% do not know they have it. 20% develop flu-like
symptoms. 1 in 150 develop the more serious neuro-invasive form
of the disease. Sacramento County reported 49 cases of
neuro-invasive WNv disease out of a population of 1.25 million, which
yields 1 per 25,000. One fatality was reported, for a ratio of
less than 1 per million. While any death is a tragedy, these low
numbers hardly justify the anxiety officials and the media have
fomented. See “West
Nile Risk Low” to help gain some perspective.
• Indiscriminate spraying kills beneficial insects like bees, as
well as predators like dragonflies. Dragonfly experts tell us
that since their reproductive cycle is much longer than that of
mosquitoes, the spraying likely will
make matters worse.
• According to the label, “This
product is highly toxic to
fish.” How can indiscriminate application from airplanes avoid
poisoning numerous ponds and waterways throughout the area?
• Officials insist that small doses are harmless. Yet
spraying with small doses is the ideal way to develop resistant strains
of various insects, which puts us at risk for serious diseases in the
future. We believe that less-dangerous pesticides should be held
abeyance for use in serious epidemics and not in a matter such as this
one. Moreover, the dictum of “the dose makes the response” stems
from the work of the 16th century physician and alchemist
Paracelsus. See “The
ABC’s of Toxicology,” which notes that “In the standard pesticide
response relationship, responses increase as dose increases.
However, some chemicals have an inverted relationship and higher
doses of the chemical ‘actually inhibit some responses that are
stimulated by much lower doses’, ” and “By insisting that only an old
and simplistic dose-response relationship can be relevant to
pesticides, pesticide proponents are hiding from modern
toxicology.” Also see our discussion
about how low doses of substances are not necessarily safe.
• Some years back SYMVCD cultured its own Romanomermis
culicivorax, a mosquito-parasitic nematode that has exhibited a
success rate at killing mosquitoes and has no human or environmental
risks. In some settings single inundative releases have
excellent results for a matter of years. Why has this practice been
replaced with indiscriminate spraying from airplanes? Culturing
Romanomermis is a more labor-intensive process, but it is highly
effective and keeps money in our community instead of paying a
Mississippi firm to douse us with a pesticide manufactured by a
company. See a more detailed discussion here.
• Again, as to effectiveness, Ray Parsons, Ph.D., Medical
entomologist & assistant director at Houston, Texas Mosquito
Control Division states, “It is difficult to determine the
effectiveness of pesticide spraying because there are currently no
accurate means of measuring Culex mosquito populations. Therefore,
scientists cannot accurately determine what percentage of the
population has decreased after spraying.” See "The Truth About Mosquitoes and West Nile
virus," a fact sheet from Beyond
Pesticides. As we noted in the op-ed, mosquito populations
decline after the peak anyway. Claims by officials that the spray
was effective are based on unscientific analysis, and the conclusions
have not been verified by independent analysis.
• According to David Pimentel, Ph.D., an entomologist at Cornell
University, close to 99.9 % of sprayed chemicals go off into the
environment where they can have detrimental effects on public health
and ecosystems, leaving 0.1% to actually hit the target pest. See
"The Truth About Mosquitoes and West Nile
• According to the New York State Department of Health, more
people were reported to have gotten sick from pesticide spraying than
from exposure to WNv in 2000. See
"The Truth About Mosquitoes and West Nile
• The SYMVCD manager has admitted that he is not following CDC
protocols – in April of 2006 he reported to the Sacramento
Environmental Commission that he had not put into place the staff
necessary to handle another intense West Nile season using larval
control, yet he has been predicting an intense year since October of
2005 (“Birds are first line of viral defense,” Brian Joseph, Sacramento
Bee, October 2, 2005).
• We met with the district manager on July 5, and we agreed to
canvas hot spots and distribute door hangers with volunteers. We
canvassed the hot spots immediately. We were given maps of areas
with several thousand homes, yet we were supplied with only 300 door
hangers. We had trouble getting more hangers, and only weeks
later were eventually given 400 more. However, the district
manager criticized the volunteer effort as not being enough.
SYMVCD can afford approximately $700,000 to blanket Sacramento with
poison in the summer of 2005, the last resort in the CDC protocol, yet
it must depend on volunteers to
educate people, a critical initial step in the CDC protocol.
Something is very wrong with this picture.
• The district manager told us that he thought the biggest
problem in terms of growing mosquitoes was in the back yards of
town. We thus recommended that SYMVCD hold a “backyard day,” with
many types of publicity, including newspaper, television, City Council,
sound trucks in neighborhoods, etc. This has never
materialized. Instead, SYMVCD sprayed Davis after the precipitous
drops in infected mosquitoes and total counts noted in the op-ed.
• Pyrethrins decompose rather rapidly in the sunlight, but what
about in the shade or in carpets in homes where children play?
The synergist, PBO, is not photo-sensitive at all, and we see estimates
of half-life of 6 days to 6 months. A recent study out of UC
Berkeley concluded that PBO from the spraying in Sacramento last year
got into the waterways and synergized toxic chemicals that were already
there, making them twice as toxic. So much for PBO rapidly
deteriorating after spraying. Furthermore, it is not clear what
compounds PBO changes into, nor is the safety of those compounds clear.
• We believe that people do not have the right to breed
mosquitoes in their back yards and expose others to disease. We
also believe that SYMVCD does not have the right to expose all of us to
toxic chemicals in an ineffective attempt to protect those who are most
at risk to WNv. We thus envision a two-pronged effort: 1)
aggressive efforts to educate people and help them maintain their homes
properly and eliminate backyard
sources, and 2) aggressive efforts to protect those most at risk in the
population via education, good screens, long-sleeve shirts, mosquito
• Even if we assume that adulticiding is effective, no rigorous
risk-benefit analyses have been done.
• A physician would have a difficult time recommending a vaccine for
WNv, if one were to be developed, because the risk of adverse reaction
to the standard pharmaceutically prepared vaccine is greater
than the risk of exposure to serious disease from WNv.
• The indicator of 5-infected-mosquitoes-per-1000-trapped has not
been justified scientifically. We know of nothing in the
scientific literature to justify that figure, and we have been supplied
no citations. In any event, such a ratio is completely irrelevant
as to the risk of the disease without an accurate estimate of the total
Culex (the suspected vector) population. We have seen none.
• The typical pattern of WNv as it has come across the country
has been a mild first year, a peak in the second year, and a tapering
off in subsequent years. Many scientists recommend that the
disease should be allowed to run its course without attempted
intervention with adulticides.
• Mosquito districts were set up to combat serious illnesses such
malaria and yellow fever. We believe that the SYMVCD is violating
the public trust by responding in this way to a much less dangerous
disease. Any resistance built up in insects from these
applications will hamper efforts to deal with serious problems in the
We do indeed believe that there is a serious public-health problem in
this area, but it is not WNv.