Forensic insects attracted to human cadavers in a vehicular environment in Riyadh, Saudi Arabia

Insect fauna attracted to cadavers at the crime scene can be identified and used to estimate the post-mortem interval (PMI). In the current study, insects associated with two human cadavers in a vehicular environment were collected and analysed. The first cadaver was found five days' post mortem in a garage. The second cadaver was found in a car ten days after his death. The weather conditions were obtained from the nearest weather station located to the scenes of the death. During the study, six adults, 32 larvae and egg batches were collected from case 1 and identified as Chrysomya albiceps Wiedemann (Diptera: Calliphoridae). From the second case, two larvae of Megaselia scalaris Loew (Diptera: Foridae) and seven larvae of Musca domestica L. (Diptera: Muscidae) were identified. mPMI ranged from five to twelve days. This information expands the knowledge on the insect fauna in the vehicular environment, which could be used to assist estimation of the PMI.

Molecular identification of ticks infesting camels and the detection of their natural infections with Rickettsia and Borrelia in Riyadh province, Saudi Arabia

The present work aimed to identify camel ticks Hyalomma dromedarii and Hyalomma marginatum using direct sequence of the mitochondrial 16S rRNA gene and the detection of their natural infection rate with Rickettsia and Borrelia using the PCR/ hybridization method for amplification of the citrate synthase (gltA) gene. The phylogenetic analysis showed 99% similarity between Hyalomma dromedarii and its reference with accession # L34306.1, as well as between Hyalomma marginatum and its reference with accession # KT391060.1 obtained from GenBank data base. The prevalence of H. dromedarii and H. marginatum was about 99% and 1%, respectively. The intraspecific variation among H. dromedarii ranged between 0.2-6.6%. The interspecific variation between H. dromedarii and H. marginatum was 18.3%. PCR/hybridization of the sampled H. dromedarii detected about 31%, 37% and 18% natural infection with Rickettsia, Borrelia and co-infection with both pathogens, respectively. In contrast, none of Rickettsia or Borrelia was detected in H. marginatum. The present study emphasizes the accuracy of the identification of camel ticks based on molecular techniques. The ability of H. dromedarii to spread more than one disease is an important issue from the epidemiological standpoint. Future epidemiological research should be carried out in Saudi Arabia to monitor the distribution of tick species and suggest effective control strategies.