Volume 30, Number 12—December 2024
Dispatch
Ehrlichia canis in Human and Tick, Italy, 2023
Figure
![Maximum-likelihood phylogenetic tree of Ehrlichia canis 16S rRNA sequences detected in a patient’s blood and in a Haemaphysalis punctata tick removed from the patient in Italy, 2023. Boldface indicates sequences amplified in the study area. The tree was inferred including 12 partial sequences (281 bp) under the maximum-likelihood method based on the general time reversible model (10) and a discrete gamma distribution was used to model evolutionary rate differences among sites (5 categories) (+G, parameter = 0.3727). The percentage of trees in which the associated taxa clustered together is shown next to the branches. A consensus sequence of Rickettsia raoultii (MT509815) in a human from Russia was used as outgroup. The tree with the highest log likelihood (−559.69) is shown, obtained from 1,000 bootstrap replications with MEGA X software (11). Scale bar indicates nucleotide substitutions per site.](/eid/images/24-0339-F1.jpg)
Figure. Maximum-likelihood phylogenetic tree of Ehrlichia canis 16S rRNA sequences detected in a patient’s blood and in a Haemaphysalis punctata tick removed from the patient in Italy, 2023. Boldface indicates sequences amplified in the study area. The tree was inferred including 12 partial sequences (281 bp) under the maximum-likelihood method based on the general time reversible model (10) and a discrete gamma distribution was used to model evolutionary rate differences among sites (5 categories) (+G, parameter = 0.3727). The percentage of trees in which the associated taxa clustered together is shown next to the branches. A consensus sequence of Rickettsia raoultii (MT509815) in a human from Russia was used as outgroup. The tree with the highest log likelihood (−559.69) is shown, obtained from 1,000 bootstrap replications with MEGA X software (11). Scale bar indicates nucleotide substitutions per site.
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