DNA detection rates of host mtDNA in bloodmeals of human body lice (Pediculus humanus L., 1758)

Abstract

Using polymerase chain reaction, we investigated the extent to which digestion affects the potential to amplify 12S mitochondrial DNA sequences from bloodmeals of individual human body lice (Pediculus humanus L.) (Phthiraptera, Pediculidae) up to 72 h after feeding on a surrogate rabbit host (Oryctolagus cuniculus L.) (Lagomorpha, Leporidae). Two rabbit-specific primer pairs were developed to produce amplicons of 199 bp and 283 bp, the smaller of which was found to have a significantly slower decay rate. Median detection periods (T50) for the amplicons were 20 h and 12 h, with maximum detection periods of 24 h and 12 h, respectively, suggesting an inversely proportional linear relationship between amplicon size and digestion time. The data provide an indication of timeframes essential for the design of forensic sampling protocols and a basis for investigating the feeding frequency of human lice.

Autosomal Short Tandem Repeats and anAluInsertion Polymorphism Are Detectable inCimex lectulariusL. (Hemiptera: Cimicidae) for 48 Hours after Human Blood Ingestion1

“…We did not calculate decay rates for human DNA in bed bugs, because we found that recovery for any one time point was variable and a function of the blood meal or the individual bed bug. However, we did recover amplifiable human DNA up to 72 h after blood feeding with all 9 samples, as shown previously for rabbit DNA from body lice (Davey et al 2007).…”

“…Szalanski et al (2006b) identified a mtDNA marker 7 d post-blood feeding and a 271 bp STR marker 60 d post-blood feeding. When attempting to detect rabbit DNA in human body lice, Pediculus humanus humanus L. (Phthiraptera: Pediculidae), a 199 basepair (bp) amplicon had a significantly slower decay rate than a 283 bp amplicon, suggesting that amplicon size may be inversely proportional to decay rate (Davey et al 2007). We did not calculate decay rates for human DNA in bed bugs, because we found that recovery for any one time point was variable and a function of the blood meal or the individual bed bug.…”

Mosquito vector‐associated microbiota: Metabarcoding bacteria and eukaryotic symbionts across habitat types in Thailand endemic for dengue and other arthropod‐borne diseases

“…Others have shown that mosquito midgut bacterial communities are dynamic and vary significantly with respect to bloodfed state (Wang et al., 2011). Host DNA is detectable by sequencing even when engorgement is no longer visible (Davey, Casey, Burgess, & Cable, 2007; Lee et al., 2002), and quite interestingly, we identified 18S rRNA sequences belonging to phylum Chordata, class Mammalia, in a few of our mosquito samples. Although their presence was not frequent enough across pools to conduct further analyses, with the everimproving depth of sequencing provided by technological advances, we envision future studies being able to simultaneously characterize both microbial community composition and vertebrate host utilization from field‐collected mosquitoes.…”

Combining Real-Time Polymerase Chain Reaction Using SYBR Green I Detection and Sequencing to Identify Vertebrate Bloodmeals in Fleas

“…Mitochondrial DNA is a commonly used and effective target for bloodmeal assays because of its high copy number and rapid rate of evolution relative to nuclear DNA (Kent 2009). Optimal amplicon size for real-time assays using SYBR Green I as a ßuorescent reporter is between 75 and 200 base pairs (bp) (Bio-Rad Laboratories 2006), and the ability to detect partially digested bloodmeals via PCR appears to be inversely related to amplicon size (Kirstein and Gray 1996, Kent and Norris 2005, Davey et al 2007). Therefore, we sought to identify primers that would amplify a relatively small mitochondrial gene fragment from vertebrates without amplifying ßea DNA.…”