Ticks are obligatory hematophagous ectoparasites and vectors of many animal and human pathogens. Chemosensation plays a significant role in tick communication with their environment, including seeking out blood meal hosts. Studies on the structure and function of Haller’s organ and its components have improved our understanding regarding tick olfaction and its chemical ecology. Compared with the knowledge on insect olfaction, less is known about the molecular basis of olfaction in ticks. This review focused on the chemosensory-related candidate molecules likely involved in tick olfaction. Members of the ionotropic receptor family and a new class of odorant-binding proteins are now known to be involved in tick olfaction, which appear to differ from that of insects. These candidate molecules are more closely related to those of mites and spiders than to other arthropods. The amino acid sequences of candidate niemann–pick type C2 and microplusin-like proteins in ticks exhibit features indicating their potential role as binding proteins. In the future, more comprehensive pertinent research considering the existing shortcomings will be required to fully understand the molecular basis of tick olfactory chemoreception. This information may contribute to the development of new molecular-based control mechanisms to reduce tick populations and related disease transmission.
Background: In the normal life cycle of the parasite (Echinococcus multilocularis) that causes alveolar echinococcosis, domestic and wild carnivores act as definitive hosts, and rodents act as intermediate hosts. The presented study contributes to the research on the distribution and transmission pattern of E. multilocularis in China having identified sheep as an unusual intermediate host taking part in the domestic transmission of alveolar echinococcosis in Gansu Province, China. Methods: From 2020 to 2021, nine whitish different cyst-like were collected from the liver of sheep in Gansu Province for examination. A near complete mitochondrial (mt) genome and selected nuclear genes were amplified from the cyst-like lesion for identification. To confirm the status of the specimen, comparative analysis with reference sequences, phylogenetic analysis, and network analysis were performed. Results: The isolates displayed ≥ 98.87% similarity to E. multilocularis NADH dehydrogenase sub-unit 1 (nad1) (894 bp) reference sequences deposited in GenBank. Furthermore, amplification of the nad4 and nad2 genes also confirmed all nine samples as E. multilocularis with > 99.30% similarity. Additionally, three nuclear genes, pepck (1545 bp), elp-exons VII and VIII (566 bp), and elp-exon IX (256 bp), were successfully amplified and sequenced for one of the isolates with 98.42% similarity, confirming the isolates were correctly identified as E. multilocularis. Network analysis also correctly placed the isolates with other E. multilocularis. Conclusions: As a result of the discovery of E. multilocularis in an unusual intermediate host, which is considered to have the highest zoonotic potential, the result clearly demonstrated the necessity for expanded surveillance in the area. Graphical
Cystic echinococcosis (CE) caused by the parasite Echinococcus granulosus is a zoonotic disease of global concern. Because most African countries have not yet conducted systematic studies on CE, it is difficult to determine its exact status. However, as with any parasitic zoonotic disease, the first step in developing a comprehensive management and control strategy is to identify the host range, transmission risk factors, and national and regional epidemiological data. This review evaluated and summarized articles on CE retrieved from the PubMed and Africa Journal Online (AJOL) databases. Inclusion criteria were studies (including case reports) focused on the prevalence of CE in animals and humans between 1970 and 2025. This review revealed that although numerous early studies on CE exist, only a few were conducted in Africa from 1970 to 2025. Furthermore, data regarding population genetic composition and the role of wildlife in CE transmission remain scarce. This review systematically evaluated the prevalence and transmission of CE in Africa and identified priority areas for surveillance and control.