APPENDIX I-1B:  E-Mail from John Pape Epidemiologist, State of Colorado, July 5, 2007.


Date: Thu, 05 Jul 2007 17:57:18 ‑0600

From: John Pape <>

To: MAZIAR ANNE LEE <Anne.Maziar@Colorado.EDU>, walter@Colorado.EDU,

Cc: Heath Harmon <>,

    Joe Malinowski <>

Subject: Re: report on meeting with state health today (fwd)


Ms. Maziar and colleagues,


I read with interest the 32 emails that Ms. Maziar forwarded to me regarding

the recent meetings with the Longmont City Council and Boulder County

Commissioners. I usually don't respond to such blast emails as I find this

accomplishes little with groups in which to paraphrase Mr. Walters statement

"Predetermined assumptions guides [their] whole program".


However since I was personally attacked in the string of discussions, I felt

a need to respond to clarify some points that were made.  I don't have the

time to address  the numerous  inaccuracies and errors in these email

strings, but would offer the following comments for consideration.


First, the reason for which both of these meetings were held was to discuss

trigger points and issues to consider when deciding if adult mosquito

control (spraying) should be conducted during a WNV outbreak.  This was a

very narrow focus, not a discussion on mosquito control 101.  However by

leaving out this important context, it makes statements like "Larviciding

was not mentioned..."   or the "best approach to control ... is aerial

spraying" sound much more sinister and ominous.  Maybe the persons attending

this meeting were unaware of the purpose of the discussion?


However, I have observed over my years in public health that using quotes or

statements out of context or attributing statements to a person they did not

make  is a common tactic with groups advocating a specific agenda. I would

be like to hear the tape where I used the term "wall to wall spraying" that

is mentioned several times in these emails.  A comment attributed to me

included "Pape implicitly dismissed larviciding", again used  out of context

and contrary to written information we have been promoting for years ( i.e

one of the prevention 4 D's ‑‑ drain standing water).  Even the email string

contradicted this statement as in the Longmont City Council notes it states

" He confirmed for Mayor Pirnack that the larvicide's control in City limits

is very effective."


We have been using surveillance data to determine the best ways to prevent

human WNV infections.  One pattern that has occurred several times is the

initiation of spraying well after the peak of the transmission season, when

it has limited impact on preventing human illness. The spraying in Longmont

at the end of August last year is a good example of this.   Our goal is to

limit the times when spraying is used and if used that it has the most

impact on preventing infections based on surveillance data we have been

collecting for 5 years.


To that end our data has shown approximately 85% of WNV cases are infected

between July 1 and the second week of August. But due to reporting delays,

most human cases are reported in August and September. Culex populations

tend to peak in mid to late July.  Thus, based on available surveillance

data,  the most effective time to do adult control would be in July at the

front end of the mosquito population and infection curves.  But at this

point few human cases will have been reported.


I have been discussing these findings with local decision makers to insure

that if spraying is being done for disease control purposes it is most

effective and to not spray when there would be no public health benefit. Our

mosquito‑borne arbovirus response plans was revised to reflect this with the

inclusion of the statement: "Based on epidemiological data from Colorado,

adulticiding after the third week of August will have a minimal impact on

human case totals. "  The plan also discusses trigger points as to when

spraying should be considered, so despite inferences in the email strings to

the contrary, I only recommend spraying when indicators are showing

significant human risk.  As a case in point, no spraying for disease control

was needed or recommended in Boulder County during the 2004 or 2005 seasons


based on surveillance data.


However, I cannot support this groups main position, that spraying should

not be done under any circumstance.  We have logged nearly 4,000 human

cases, many with permanent sequelae, and 76 deaths over the past 4 years

(514 cases; 8 deaths in Boulder County).  Adult mosquito control is one tool

that can lower this impact.  I have not received one report of a physician

diagnosed illness or death related to emergency ultra low volume (ULV)

mosquito spraying. 


This brings me to my final point regarding statements :" Mr. Poppy added

that there have not been any conclusive studies that link

spraying to illnesses.  Either he is totally incompetent, or he is

deliberately misrepresenting the truth. "


I have asked no spray groups repeatedly over the years to provide a

reference of a scientific article in the peer‑reviewed literature showing a

causal link between human morbidity and ULV mosquito spraying.  I have yet

to be provided with such a reference. 


However, this should be easy to document. My sister lives in a Midwest town

that conducts ground based ULV spraying for nuisance mosquitoes from May ‑

September; the truck goes down her street 1‑2 per week. This is a common

practice in the eastern and southern U.S. so the doom predicted in these

email strings should be evident in such areas.


I'm well aware of studies showing illness with high doses fed to mice, long

term chronic exposures or acute intoxications due to mishandling or improper

application and have read the MSDS sheets for adulticide products. I'm also

aware of the attempts to extrapolate such data into predictions of wide

spread human illness due to ULV applications without any supporting data.


These studies do not change my view that targeted, appropriately timed adult

mosquito control as one component of an integrated mosquito control program

can significantly reduce human morbidity and mortality.  This view appears

to be held by the majority of the CO citizens.


I actually receive more complaints from citizen about why there is no

mosquito control in their area.  Every public vote to expand or fund

mosquito control districts in Colorado since 2003 has passed by large

margins. One way to prohibit spraying, is to start a petition, get it on the

ballot and put it to a community vote.  I suspect though it wouldn't be

successful based on  a 2004 state‑wide population based survey. When asked

the question "If testing showed there were lots of West Nile Virus infected

mosquitoes in your community, would you support spraying to reduce the

number of mosquitoes?" responses were YES 84.6% (95% confidence interval

81.5 ‑ 87.3%); NO 8.5% (CI 5.9 ‑ 11.1%); DO NOT KNOW 6.8% (CI 4.8 ‑ 8.8%);

REFUSED 0.2%.  


My position of trust requires me to consider the views of all Colorado

citizens. This includes the concerns of pesticide exposure that your group

voices along with the concerns of  thousands of Coloradoans and their

families who have been adversely impacted by WNV.  While I hope most years

we do not have to resort to mosquito adulticiding, there are times when the

public health benefit of adult mosquito control will outweigh the risks

associated with spraying. 


I appreciate the opportunity to provide the context in which my comments

were made at these public meetings.  Please feel free to forward this to

other members in your email group.  JP


John Pape, Epidemiologist

Colorado Department of Public Health & Environment

4300 Cherry Creek Drive South

Denver, CO 80246