Multivariate Analysis of Risk Factors Associated with a Community Outbreak of Cryptosporidiosis in Kansas, 2003 Público
Brou, Lina (2012)
Abstract
      
      Multivariate Analysis of Risk Factors Associated with a
Community Outbreak of
      
      Cryptosporidiosis in Kansas, 2003
    
By Lina Brou
      Background: The chlorine-resistant protozoan,
Cryptosporidium, commonly associated with
daycare and swimming facilities, has emerged as the leading known
cause of recreational waterborne
diarrhea outbreaks in the United States. In the summer of 2003, an
outbreak of cryptosporidiosis
occurred among residents of one county in Kansas.
      Methods: To determine the magnitude of the outbreak and
identify risk factors for infection, we
performed a secondary analysis of a county-wide matched
case-control interview study. Subjects
included laboratory-confirmed cryptosporidiosis cases (n=63), a
random sample of clinical cases
(n=88), and age-matched controls identified by random-digit dialing
(n=302). Clinical
cryptosporidiosis was defined as diarrhea (≥3 loose stools in
a 24 hour period) for ≥ 3 days within a
one week period after June 15, 2003. Conditional logistic
regression was the primary statistical
methodology used.
      Results: The final model included the following predictors:
treated recreational water (adjusted
matched odds ratio = 7.753; 95% CI = 3.577, 16.804; p-value
<0.0001), having a child in childcare
outside of the home (amOR = 3.609; 95% CI = 1.69, 7.709; p-value =
0.0009), and having a
household contact with diarrhea (amOR = 10.575; 95% CI = 5.102,
21.916; p-value<0.0001). To
identify which facilities could be implicated, a second model
resulted in the following predictors:
Swimming Pool D (amOR = 4.324; 95% CI = 1.087, 17.209; p-value =
0.0377); Daycare 2 wading
pool (amOR = 19.475; 95% CI = 2.719, 139.464; p-value = 0.0031);
and having a household contact
with diarrhea (amOR = 7.914; 95%CI = 2.744, 22.821; p-value =
0.0001). No interaction terms were
significant and there was no indication of collinearity.
      Discussion: This is one of the largest reported U.S.
community-wide cryptosporidiosis outbreaks
and the first outbreak associated with this Cryptosporidium
subtype. Although the original source of
the outbreak was identified as a single contaminated swimming pool,
the outbreak spread throughout
the community via secondary and tertiary exposures (i.e., daycare
exposure and person-to-person
contact). It draws attention to the need for collaborative efforts
between local, state, and federal
agencies to define and develop policies that facilitate prompt
intervention to prevent community-
wide transmission of Cryptosporidium.
Table of Contents
      
      
      Table of Contents
      
      
      
      1. Background 1 
        
        
      
      1.1 Epidemiology 3
      1.2 Pathogen 4
      1.3 Environment 5
      1.4 Human Cryptosporidiosis 6
      1.5 Risk Factors in Cryptosporidiosis Outbreaks 7 
        
        
        
        
      
      2. Manuscript 13
      
      2.1 Introduction 13
      2.2 Methods 16
      2.3 Results 19
      2.4 Discussion 21
      2.5 References 26
      2.6 Tables and Figures 36
      
      
      
      3
      . Public Health Implications 42
      
      
      4.
      Appendix A: Additional Tables 44
      
      
      5.
      Appendix B: Case Questionnaire 48
    
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Primary PDF
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|  | Multivariate Analysis of Risk Factors Associated with a Community Outbreak of Cryptosporidiosis in Kansas, 2003 () | 2018-08-28 11:20:28 -0400 |  | 
Supplemental Files
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|   | Appendix B_Case Questionnaire.doc () | 2018-08-28 11:20:46 -0400 |  |