Detection and Prevalence of <em>Wolbachia</em> within the Tick <em>Ambyomma americanum</em> and Fleas (Siphonaptera) in Southeast Georgia

<p><em>Wolbachia</em> spp. are intracellular endosymbionts that have been reported from many arthropods and nematodes. However, there is little known of Wolbachia from either ticks or fleas. This is the first report of <em>Wolbachia</em> within the lone star tick, <em>Amblyomma</em> <em>americanum</em>. Samples from the coastal region of Georgia were collected and screened individually for infection with <em>Wolbachia</em> utilizing nested polymerase chain reaction (PCR) amplification targeting a fragment of the 16S rRNA gene. The average prevalence of <em>Wolbachia</em> within the sampled <em>A</em>. <em>americanum</em> was 11%. This indicates the presence of <em>Wolbachia</em> within the ticks; however, <em>wsp</em> and <em>fts</em>Z primers, which were used in the literature for determination of known strains of <em>Wolbachia</em>, failed to amplify our 16S positive samples. Phylogenetic analysis was run on the 16S sequences obtained, indicating that the amplified organisms do indeed belong in the genus <em>Wolbachia</em>. Phylogenetic analyses showed that this <em>Wolbachia</em> is different from previously reported tick endosymbionts. In addition to the initial survey, one mainland location was selected to test the temporal spread of <em>Wolbachia</em> within the tick population. The infection rate ofticks in this location is compared between the years (1998 and 2000). This comparison showed that the infection rate of <em>Wolbachia</em> significantly decreased over two years within <em>A</em>. <em>americanum</em> at this location. This data is contrary to many previous reports that <em>Wolbachia</em> quickly spread within populations of other arthropods.</p> <p>This is also the first extensive report of <em>Wolbachia</em> within the order Siphonaptera (fleas). <em>Wolbachia</em> were found within natural populations of three different families of fleas. The fleas in which <em>Wolbachia</em> have been found occurred in five different species with varying prevalence: 21% (126 of 604) in <em>Ctenocephalides felis</em>; 7% (2 of 28) in <em>Ctenocephalides</em> <em>canus</em>; 25% (2 of 8) in <em>Polygenus</em> <em>gwynni</em>; 80% 12 of 15) in <em>Orcopeas</em> <em>howardi</em>, 94% 240 of 255) in <em>Pulex</em> <em>simulans</em>; and 24% 24 of 101) in <em>Echidnophaga</em> <em>gallinacea</em>. <em>Wolbachia</em> were detected by PCR amplification utilizing a new 16S rDNA specific primer designed in our lab. Confirmation of <em>Wolbachia</em> infection utilizing <em>wsp</em> and <em>fts</em>Z primers was inconclusive depending upon flea host species. However, phylogenetic analysis of the 16S gene indicated that the fleas were infected with <em>Wolbachia</em>.</p>

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Thesis (restricted to Georgia Southern)

Discipline thesis:degree_discipline

Department of Biology

Year dc:date.available

2001

Author dc:creator

• Gorham, Christopher H.

Contributors dc:contributor

• Lance A. Durden
• William S. Irby
• Oscar J. Pung

• ETD
• Wolbachia
• Intracellular endosymbionts
• Ambloymma americanum
• Nested polymerase chain reaction
• Biochemistry, Biophysics, and Structural Biology
• Biology

Repository record dc:identifier

https://digitalcommons.georgiasouthern.edu/etd_legacy/838

OAI identifier oai:identifier

oai:digitalcommons.georgiasouthern.edu:etd_legacy-1979