PhD thesis - University of Hertfordshire Research Archive

More documents

Recommendations

Info

Percent 18 16 14 12 10 8 6 4 2 0 0-9 10-19 20-29 30-39 40-49 50-59 60-69 70-79 80+ Age group 43 Isolates (N=30,890) Quest (N=20,299) Figure 4. The age distribution of cases where isolates were received and questionnaires referred. Linkage. Of 20,387 cases where a questionnaire was received it was possible to integrate typing data in 14,383 instances (71%). Linkage was done in this direction as the questionnaires could be guaranteed to be from residents of the sentinel health authorities. Closer scrutiny of these data, however, revealed that in 116 instances (0.6%) the linked individuals were not identical (different spellings of first names; different postcodes etc) and in 382 instances (1.9%) the two records were not coincident in time (for 82 cases the specimen date occurred before the onset date and for 300 cases the specimen data was more than 28 days after the onset date). These records were considered unlinked in analyses involving linked data. Cases with linked data were no different to unlinked cases in terms of age (mean 39.4 years in both groups) or gender (68 and 69% linkage in males and females respectively) and linkage did not differ greatly across ethnic groups. The only exception to this was cases who described their ethnicity as „Other Asian‟ or „Other‟, where linkage was 65 and 50% respectively compared to 68% in other ethnic groups. These cases only accounted for 2% of all cases however.
The published work. 7.1 Epidemiological distinctions between cases of Campylobacter jejuni and Campylobacter coli infection. Standard isolation methods for campylobacters currently used by clinical microbiology laboratories in England and Wales do not differentiate the species within the Campylobacter genus. This is achieved through additional serological and biochemical testing, which is beyond the remit of routine public health microbiology. Campylobacters are therefore generally reported to national surveillance as „Campylobacter species‟ and, as a result, are often considered by investigators to be a single disease. This militates against understanding the epidemiology of individual Campylobacter species, as species-specific risk factors for infection might be obscured in an epidemiological study conducted at the genera level i.e. if a „risk factor‟ for one species is a „protective factor‟ for another. In order to assess this assumption, the exposures of 272 cases infected with C. coli (the second most common Campylobacter species, accounting for ~8% of isolations or an estimated 3700 laboratory-confirmed cases reported annually) and 3489 cases infected with C. jejuni (the most common species, accounting for ~90% of isolations, or an estimated 41,600 laboratory- confirmed cases reported annually) were therefore compared to identify epidemiological differences between the two species and to inform case definitions for future studies (paper 1 (Gillespie et al., 2002)). Although cases were similar clinically, a number of epidemiological differences were identified. Cases infected with C. coli tended to be older than those with C. jejuni and were more likely to be of Asian ethnicity. Travel abroad was important for infection with C. coli, as was the consumption of certain meats and bottled water. A number of interactions between variables were observed, giving an indication of the complexity of the epidemiology in different demographic groups and at different times of the year. 44
Page 1 and 2: Population-Based Sentinel Surveilla
Page 3 and 4: The research carried out by the can
Page 5 and 6: Dedication. This thesis is dedicate
Page 7 and 8: 7. Results (the published work). ..
Page 9 and 10: Statement identifying the degree fo
Page 11 and 12: Paper Reference Page 6 Gillespie IA
Page 13 and 14: Statement of the candidate’s cont
Page 15 and 16: Declaration form. I, Iain Andrew Gi
Page 17 and 18: 2. History. In contrast to other co
Page 19 and 20: The application of veterinary techn
Page 21 and 22: The incidence of laboratory-confirm
Page 23 and 24: were elderly or had a pre-existing
Page 25 and 26: they would for other bacterial gast
Page 27 and 28: papers (Pearson et al., 1977; Bruce
Page 29 and 30: Studies were most frequently conduc
Page 31 and 32: The content of peer-reviewed public
Page 33 and 34: infection. An approximation of the
Page 35 and 36: hypotheses a „blank canvas‟ app
Page 37 and 38: 6. Materials and methods. Regional
Page 39 and 40: presentation and severity, foreign
Page 41 and 42: together, etc). The results of the
Page 43: and improve response during the stu
Page 47 and 48: community illness was more common a
Page 49 and 50: north west England and in Yorkshire
Page 51 and 52: community was no different from oth
Page 53 and 54: provide useful insights into the ep
Page 55 and 56: Cases in case-control studies of la
Page 57 and 58: 8. Discussion. The research carried
Page 59 and 60: The sentinel health authorities wer
Page 61 and 62: fundamentally flawed. Since the app
Page 63 and 64: control studies. The potential role
Page 65 and 66: Campylobacter spp. from cattle farm
Page 67 and 68: Cameron, S., Ried, K., Worsley, A.,
Page 69 and 70: Doyle, L. P. 1948, "The etiology of
Page 71 and 72: other industrialised countries," in
Page 73 and 74: Hanel, C. M. & Atanassova, V. 2007,
Page 75 and 76: Hudson, S. J., Lightfoot, N. F., Co
Page 77 and 78: Kessel, A. S., Gillespie, I., O'Bri
Page 79 and 80: costs-of-illness, Rijksinstituut vo
Page 81 and 82: Department of Health and Human Serv
Page 83 and 84: Potter, R. C., Kaneene, J. B., & Ha
Page 85 and 86: Siemer, B. L., Harrington, C. S., N
Page 87 and 88: Sopwith, W., Birtles, A., Matthews,
Page 89 and 90: Campylobacter infection: a general
Page 91: The published work 90
Page 102 and 103:
101
Page 104 and 105:
103
Page 106 and 107:
105
Page 108 and 109:
107
Page 110 and 111:
109
Page 112 and 113:
111
Page 114 and 115:
113
Page 116 and 117:
115
Page 118 and 119:
117
Page 120 and 121:
119
Page 122 and 123:
121
Page 124 and 125:
123
Page 126 and 127:
125
Page 128 and 129:
127
Page 130 and 131:
129
Page 132 and 133:
131
Page 134 and 135:
133
Page 136 and 137:
135
Page 138 and 139:
137
Page 140 and 141:
139
Page 142 and 143:
141
Page 144 and 145:
Table A1.1: Notable events in the h
Page 146 and 147:
Year Human medicine Veterinary medi
Page 148 and 149:
Levy, A. J. 1928, "A gastro-enterit
Page 150 and 151:
Appendix 2. An assessment of the ro
Page 152 and 153:
compare the period after 2000 with
Page 154 and 155:
condition was significantly associa
Page 156 and 157:
Deaths/100,000 cases 600 500 400 30
Page 158 and 159:
Table A2.1: Factors affecting the u
Page 160 and 161:
Appendix 3. An analytical review of
Page 162 and 163:
to indigenously acquired infection
Page 164 and 165:
susceptibility to Campylobacter inf
Page 166 and 167:
year demonstrated that only the num
Page 168 and 169:
Table A3.1 Reported epidemiological
Page 170 and 171:
Table A3.3 Selected reported risk f
Page 172 and 173:
Table A3.5. The effect of various r
Page 174 and 175:
Deming, M. S., Tauxe, R. V., Blake,
Page 176 and 177:
Harris, N. V., Weiss, N. S., & Nola
Page 178 and 179:
Kist, M. & Rossner, R. 1985a, in Ca
Page 180 and 181:
Oosterom, J., den Uyl, C. H., Banff
Page 182 and 183:
Severin, W. P. J. 1982, "Epidemiolo
Page 184 and 185:
Appendix 4. The Campylobacter Senti
Page 186 and 187:
185
Page 188 and 189:
187
show all

PhD thesis - University of Hertfordshire Research Archive

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?