Volume 9, Number 1—January 2003
Research
Seasonal Dynamics of Anaplasma phagocytophila in a Rodent-Tick (Ixodes trianguliceps) System, United Kingdom
, Michael Begon*, Malcolm Bennett*, Zerai Woldehiwet*, and Nicholas H. Ogden*
Table 2
Differences in abundance of larval and nymphal Ixodes trianguliceps ticks, counted on rodents of the study, in groups of sample periods deduced from the most parsimonious negative binomial regression models of the variations in tick abundance among sample periodsa
| Months | chi square | df | p value |
|---|---|---|---|
| Larvae |
|||
| Month group 2 vs. 1 |
5.21 |
1 |
<0.03 |
| Month group 3 vs. 1 |
68.34 |
1 |
<0.001 |
| Month group 3 vs. 2 |
6.25 |
1 |
<0.025 |
| Nymphs |
|||
| Month group 2 vs. 1 | 53.75 | 1 | <0.001 |
aRodent ID was included in the models as a random effect. For larvae, month group 1 = March to early May 1997, July and December of 1997, January to late May, and July and August of 1998; month group 2 = February, August and September of 1997, and June of 1998; month group 3 = January, late May, June, October and November of 1997, and September to December 1998. For nymphs, month group 1 = January–April, September, November, and December of both 1997 and 1998; month group 2 = early May to August and October of both 1997 and 1998.