Biology subjects

Blagrove, M. S. C.

Publications and source records attributed to Blagrove, M. S. C..

6 recordsLinked to original sources

bioRxiv2026

Integrated behavioural, morphological, and reproductive responses reveal a trade-off during diapause in Culex pipiens

Diapause is a critical adaptive strategy that enables temperate mosquito species to survive adverse environmental conditions and maintain population persistence across seasons. In Culex pipiens, diapause plays a key role in overwintering and influences the seasonal dynamics of arbovirus transmission. However, diapause expression is often assessed using single traits, limiting our understanding of its integrated physiological basis and variation among populations. In this study, we investigated the behavioural, morphological, and reproductive signatures of diapause across three laboratory strains of Culex pipiens (Mogden, Pirbright, and Pirbright Hybrid) reared under diapause-inducing (10 {degrees}C), cold (14 {degrees}C), and control (26-27 {degrees}C) conditions. We quantified blood-feeding behaviour, wing size as a proxy for somatic growth, and spermatheca size as an indicator of reproductive development. Diapause-inducing conditions resulted in a coordinated phenotype characterised by strong suppression of blood-feeding, increased somatic size, and marked inhibition of reproductive development. Mosquitoes reared at 10 {degrees}C exhibited near-complete feeding inhibition and significantly reduced spermatheca size, consistent with reproductive arrest, while those reared at 14 {degrees}C showed intermediate phenotypes. In contrast, control mosquitoes displayed active feeding and fully developed reproductive structures. Wing size increased progressively with decreasing temperature, with the largest individuals observed under diapause-inducing conditions. When analysed together, wing size and spermatheca development exhibited opposing responses across temperature treatments, revealing a strong negative association and indicating a trade-off between somatic growth and reproductive investment. This integrated response supports the interpretation of diapause as a coordinated life-history strategy involving resource reallocation towards survival. Additionally, diapause expression varied among strains, with the Mogden strain showing reduced sensitivity compared with Pirbright and hybrid populations, highlighting the role of genetic background in diapause plasticity. These findings demonstrate that diapause in Culex pipiens is a multi-trait, plastic phenotype with important implications for overwintering success and the seasonal dynamics of arbovirus transmission in temperate regions.

ecology↗

bioRxiv2025

Evaluating the Role of Anopheles Mosquitoes in the Global Spread of Arboviruses: A Review of Laboratory-Confirmed Viral Competence

Mosquito-borne diseases are a major global health concern, infecting up to 700 million people annually and causing over one million deaths. Of the several genera of biting mosquito, species of Anopheles are mostly studied for their ability (vector competence) to transmit Plasmodium protozoan parasites, some species of which cause malaria. More than 480 species of Anopheles have been described worldwide and about 70 of these are responsible for Plasmodium spp. transmission. However, the focus on Anopheles as vectors of Plasmodium has led to a relative lack of study about the ability of Anopheles to transmit viruses. Some Anopheles species have been experimentally confirmed as competentfor various arboviruses. In most cases they are secondary vectors, with relatively low competence, contributing to overall transmission while other species of mosquito or other vector are responsible for sustained transmission. Although secondary vectors may contribute less to transmission, they may play important epidemiological roles by extending transmission seasons and/or providing a means of virus overwintering. Here, we conducted an extensive review of scientific repositories, accessing a diverse range of journals and reports to build an exhaustive database of known Anopheles competence for arboviruses. Opinion pieces, modelling papers lacking experimental confirmation, and papers without vector competence data were excluded. In total, we reviewed 7,343 papers, and after exclusions, we retained 427 papers. We analysed these data, cross-referenced with ability to undergo diapause and geographical range. Our results show that some Anopheles spp. have the potential to be secondary vectors of some arboviruses, as well as undergoing diapause as adults in temperate regions of their range. Hence, we infer they could also play an epidemiologically significant role in the overwintering of mosquito-borne viruses. Author SummaryMosquito-borne diseases remain a major global health challenge, causing over one million deaths annually. Though Anopheles mosquitoes are widely studied for their spread of parasites that cause malaria, much less is known about their interaction with viruses. In this study we reviewed scientific articles to identify their role in the spread of mosquito-borne viruses. We examined studies that showed experimental evidence of transmission in the laboratory, and thus could potentially contribute to transmission as secondary vectors. Additionally, some Anopheles species in temperate regions can survive winter in a dormant state (diapause) as adults, which could enable viruses to persist between transmission seasons. Together, these results suggest that Anopheles mosquitoes may play a larger role in virus transmission than is currently appreciated, especially in temperate regions.

ecology↗

bioRxiv2024

Meta-analyses of Culex blood-meals indicates strong regional effect on feeding patterns

Understanding host utilization by mosquito vectors is essential to assess the risk of vector-borne diseases. Many studies have investigated the feeding patterns of Culex mosquitoes by molecular analysis of blood-meals from field collected mosquitoes. However, these individual small-scale studies only provide a limited understanding of the complex host-vector interactions when considered in isolation. Here, we analyse the Culex blood-feeding data from 90 publications over the last 15 years to give a global insight into the feeding patterns of Culex mosquitoes, with particular reference to vectors of currently emerging Culex-borne viruses such as West Nile and Usutu. Data on 26,857 blood-meals from 71 different Culex species were extracted from published literature. The percentage of blood-meals on amphibian, avian, human, non-human mammalian, and reptilian hosts was determined for each Culex species. Our analysis showed that feeding patterns were not significantly explained by mosquito species-level phylogeny, indicating that external factors play an important role in determining mosquito feeding patterns. For Cx. quinquefasciatus, Cx. pipiens complex, and Cx. tritaeniorhynchus, feeding patterns were compared across the worlds seven biogeographical realms. Culex tritaeniorhynchus, Cx. pipiens complex and Cx. quinquefasciatus all had significantly varied feeding patterns between realms. These results demonstrate that feeding patterns of Culex mosquitoes vary between species but can also vary between geographically distinct populations of the same species, indicating that regional or population-level adaptations are major drivers of host utilization. Ultimately, these findings support the surveillance of vector-borne diseases by specifying which host groups are most likely to be at risk. Author summaryBeing aware of mosquito biting behaviour is essential to determine the threat of mosquito-borne diseases. Studying the feeding patterns of Culex mosquitoes is crucial as these mosquitoes are vectors of currently emerging or re-emerging arboviruses such as West Nile and Usutu. Feeding behaviour of Culex mosquitoes has been examined in many individual small-scale studies. These studies only focus on the feeding patterns in a specific area. To gain a more global understanding of these feeding patterns we analysed all available Culex blood-feeding data from the last 15 years. In summary, data on 26,857 blood-meals from 71 different Culex species was collected. For each species the percentage of blood-meals on different host groups was determined. We analysed the relationship between feeding patterns and mosquito phylogeny, which showed that phylogeny alone could not explain feeding patterns. These results indicate that external factors such as land use and climate could play an important role in determining feeding patterns. For further analysis we determined the feeding patterns for three important vector species, Cx. quinquefasciatus, Cx. pipiens complex, and Cx. tritaeniorhynchus in different biogeographical realms. All three species showed different feeding patterns in the included realms. Thus, the same species can have different feeding patterns in different regions, indicating the importance of local surveillance.

ecology↗

bioRxiv2022

Monkeypox virus shows potential to infect a diverse range of native animal species across Europe, indicating high risk of becoming endemic in the region

BackgroundMonkeypox is a zoonotic virus which persists in animal reservoirs and periodically spills over into humans, causing outbreaks. During the current 2022 outbreak, monkeypox virus has persisted via human-human transmission, across all major continents and for longer than any previous record. This unprecedented spread creates the potential for the virus to spillback into local susceptible animal populations. Persistent transmission amongst such animals raises the prospect of monkeypox virus becoming enzootic in new regions. However, the full and specific range of potential animal hosts and reservoirs of monkeypox remains unknown, especially in newly at-risk non-endemic areas. MethodsHere, utilising ensembles of classifiers comprising different class balancing techniques and incorporating instance weights, we identify which animal species are potentially susceptible to monkeypox virus. Subsequently, we generate spatial distribution maps to highlight high-risk geographic areas at high resolution. FindingsWe show that the number of potentially susceptible species is currently underestimated by 2.4 to 4.3-fold, and that a high density of wild susceptible species are native to Europe. We provide lists of these species, and highlight high-risk hosts for spillback and potential long-term reservoirs, which may enable monkeypox virus to become endemic. InterpretationWe highlight the European red fox and brown rat, as they have established interactions with potentially contaminated urban waste and sewage, which provides a mechanism for potential spillback. We anticipate that our results will enable targeted active surveillance of potential spillback event, to minimise risk of the virus becoming endemic in these regions. Our results also indicate the potential of domesticated cats and dogs (latter now confirmed) being susceptible to monkeypox virus, and hence support many health organisations advice for infected humans to avoid physical interaction with pets.

ecology↗

bioRxiv2022

Genetic and microbial diversity of the invasive mosquito vector species Culex tritaeniorhynchus across its extensive inter-continental geographic range

Culex (Cx.) tritaeniorhynchus is a mosquito species with an extensive and expanding inter-continental geographic distribution, currently reported in over 50 countries, across Asia, Africa, the Middle East, Europe and now Australia. It is an important vector of medical and veterinary concern, capable of transmitting multiple arboviruses which cause significant morbidity and mortality in human and animal populations. In regions endemic for Japanese encephalitis virus (JEV) in Asia, Cx. tritaeniorhynchus is considered the major vector and this species has also been shown to contribute to the transmission of several other significant zoonotic arboviruses, including Rift Valley fever virus and West Nile virus. Significant variation in vectorial capacity can occur between different vector populations. Obtaining knowledge of a species from across its geographic range is crucial to understanding its significance for pathogen transmission across diverse environments and localities. Vectorial capacity can be influenced by factors including the mosquito genetic background, composition of the microbiota associated with the mosquito and the co-infection of human or animal pathogens. In addition to enhancing information on vector surveillance and potential risks for pathogen transmission, determining the genetic and microbial diversity of distinct populations of a vector species is also critical for the development and application of effective control strategies. In this study, multiple geographically dispersed populations of Cx. tritaeniorhynchus from countries within Europe, Africa, Eurasia and Asia were sampled. Molecular analysis demonstrated a high level of genetic and microbial diversity within and between populations, including genetic divergence in the mosquito CO1 gene, as well as diverse microbiomes identified by 16S rRNA gene amplicon sequencing. Evidence for the detection of the endosymbiotic bacteria Wolbachia in some populations was confirmed using Wolbachia-specific PCR detection and sequencing of Wolbachia MLST genes; in addition to PCR-based detection of insect-specific viruses. Laboratory vector competence showed Cx. tritaeniorhynchus from a Greek population are likely to be competent vectors of JEV. This study expands understanding of the diversity of Cx. tritaeniorhynchus across its inter-continental range, highlights the need for a greater focus on this invasive vector species and helps to inform potential future directions for development of vector control strategies.

genetics↗

bioRxiv2020

Divide and conquer: machine-learning integrates mammalian, viral, and network traits to predict unknown virus-mammal associations

Our knowledge of viral host ranges remains limited. Completing this picture by identifying unknown hosts of known viruses is an important research aim that can help identify zoonotic and animal-disease risks. Furthermore, such understanding can be used to mitigate against viral spill-over from animal reservoirs into human population. To address this knowledge-gap we apply a divide-and-conquer approach which separates viral, mammalian and network features into three unique perspectives, each predicting associations independently to enhance predictive power. Our approach predicts over 20,000 unknown associations between known viruses and mammalian hosts, suggesting that current knowledge underestimates the number of associations in wild and semi-domesticated mammals by a factor of 4.3, and the average mammalian host-range of viruses by a factor of 3.2. In particular, our results highlight a significant knowledge gap in the wild reservoirs of important zoonotic and domesticated mammals viruses: specifically, lyssaviruses, bornaviruses and rotaviruses.

ecology↗