Research Articles (Veterinary Tropical Diseases)

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Antibody kinetics and shedding dynamics of MERS-CoV in dromedary camels from different production systems in Kenya : a longitudinal cohort study
Wangilam, Rinah Sitawa; Nyariki, Thomas; Nyaguthii, Dickson Machira; Wachira, Timothy Muthui; Kimutai, Joshua; Azegele, Allan; Ndany, Romona; Ngoci, James; Muasa, Bridgit; Njogu, George; Gathura, Peter Baaro; Gardener, Emma G.; Ihab, El Masry; Kamau, Joseph; Ofwete, Robert; Makungu, Chitwambi; Shittu, Aminu; Beba, Charles; Fasina, Folorunso Oludayo (Springer, 2026-03-12)
Understanding long-term antibody kinetics in different camel production systems is crucial for risk assessment for Middle East respiratory syndrome coronavirus (MERS-CoV), a zoonotic pathogen first detected in humans in Saudi Arabia. Though the virus is endemic in dromedary camels across Africa, the Middle East, and parts of South Asia, zoonotic transmission outside of the Arabian Peninsula is undocumented. A retrospective analysis of longitudinal surveillance data of MERS-CoV was conducted on 2460 serum samples collected from 174 camels in three high-risk counties of Kenya from April 2018 to March 2021. Data were analyzed using descriptive statistics, logistic regression, and survival analysis. A total of 93/174 (53.4%) camels were seropositive at least once (animal-level), while 882/2460 (35.85%) of all serum samples tested seropositive (sample-level). Data were analyzed using descriptive statistics, logistic regression and survival analysis. A total of 93/174 (53.4%) camels were seropositive at least once. All camels in the pastoral system seroconverted, exhibiting significantly higher odds of seropositivity (OR: 9.4) compared to ranched camels, and camels above 3 years (OR: 21.2) are more likely to be seropositive compared to young ones. The median duration of seropositivity was 21 days (IQR: 11–53), varying significantly by geographical site. Camels from Garissa and Soysambu have 97% (aOR: 0.03 (CI95%: 0.001–0.79; p = 0.035) and 98% (aOR: 0.02 (CI95%: 0.001–0.48; p = 0.015) longer durations of seropositivity than those from Isiolo. The study demonstrates the spatiotemporal and biological variability of antibody levels, indicative of fluctuations in viral exposure and the resultant immune response among the camel herds. Thus, camel production practices, not just seroprevalence, drive MERS-CoV infection dynamics, demanding surveillance and stewardship strategies that are tailored to specific production systems to effectively mitigate zoonotic risk.
The journey into the ecology and distribution of the genus Amblyomma in southern Africa
Smit, Andeliza; Morar-Leather, Darshana; Neves, Luís C.B.G. (Elsevier, 2026-04)
The genus Amblyomma represents a fascinating and ecologically diverse group of hard ticks, widely distributed across southern Africa. Despite their importance as vectors of numerous pathogens, many species remain poorly studied, with limited ecological, seasonal, and distributional records. In this review we discuss observed patterns of sympatry and parapatry, noting that reproductive interference mediated by species-specific attraction-aggregation-attachment (AAA) pheromones may play a key role in shaping species boundaries. Molecular analyses using mitochondrial markers (12S rRNA, 16S rRNA, coi, and cytb) reveal high intraspecific variation within A. variegatum. The limited differentiation between A. pomposum and A. variegatum suggests recent divergence, motivating further genome-wide investigations. Additionally, we document the introduction of A. hebraeum and A. lepidum into established ranges of other species, emphasising the need for ongoing surveillance to assess the ecological consequences of such events. Finally, we outline an integrated, multi-pronged approach for advancing the understanding of Amblyomma ecology, species boundaries, and distribution, combining extensive field sampling, genome-wide molecular tools, pheromone studies, biological compatibility experiments, and curated voucher-linked data. This holistic framework aims to resolve taxonomic ambiguities, clarify evolutionary relationships, and guide future research on this medically and veterinary significant genus. HIGHLIGHTS • Identifies gaps in pheromone and reproductive data for understudied species. • Highlights unresolved distributions and taxonomic ambiguities in Amblyomma. • Emphasises the lack of set standards for species delineation. • Underlines an approach to address current gaps in Amblyomma ecology, distribution and phylogenetics in southern Africa.
Comparative genomics of Bacillus anthracis A and B-clades reveals genetic variation in for spore germination
Mokgokong, Sankwetea Prudent; Hassim, Ayesha; Mafuna, Tendo; Turner, Wendy C.; Van Heerden, Henriette; Lekota, Kgaugelo Edward (Elsevier, 2025-09)
Bacillus anthracis, the causative agent of anthrax, is composed of three genetic clades (A, B, and C). Clade-A is the most common and distributed worldwide, B-clade has a narrow geographic distribution, and C-clade is rare. South Africa's Kruger National Park (KNP) has high diversity of B. anthracis, with strains from A and B clades described from its northernmost region, Pafuri. We employed whole genome sequencing to investigate the genomic diversity of B. anthracis strains isolated from animal carcasses (n = 34) during the 2012-2015 outbreaks. Whole-genome single-nucleotide polymorphism (wgSNP) analysis assigned the 2012-2015 B. anthracis genomes to the A-clade branch, distributed across the branch's two minor sub-clades A.Br.005/006. Additionally, pan-genomic analysis distinguished the A- and B-clade genomes, identifying unique accessory genes. Notable genetic differences include the biosynthetic spore cell wall genes; long-chain fatty acid CoA ligases (FaD13), Bacillus collagen-like protein of anthracis (BclA) involved in the exosporium germination, as well as a truncated murein DD-endopeptidase (mepH) found in the pXO2 plasmid of the B-clade strains. The tryptophan synthase subunit alpha gene (trpA), which results in a pseudogene in B-clade genomes separates the A- and B-clade genomes. These differences in biosynthetic cell wall genes suggest variation in adaptability or cell growth of the B-clade strains in the environment, further influenced by the truncation of the trpA gene involved in spore germination. The A.Br.005/006-clade strains in KNP exhibit higher genetic diversity, which may enhance their resilience to environmental stressors. In contrast, the KNP B-clade (B.Br.001/002) strains show limited genetic variation, potentially reducing their adaptability. This pattern is evident through whole-genome SNP analysis and pan-genomics investigating the evolution of B. anthracis.
WHO preferred product characteristics for bivalent Salmonella Typhi/Paratyphi A vaccine for comprehensive protection against enteric fever – key considerations and research gaps
Pavon, Ana Belen Ibarz; Clemens, John; Craviotto, Alejandro; Crump, John A.; Garrett, Denise O.; Gordon, Melita A.; John, Jacob; Keddy, Karen Helena; Laurens, Matthew B.; Liu, Xinxue; Marks, Florian; Pollard, Andrew J.; Saha, Senjuti; Wilder-Smith, Annelies (F1000 Research Ltd., 2025-09-15)
In 2021, Salmonella Paratyphi A caused >2 million illnesses, resulting in >14,000 deaths, most of which occurred among children under 5 years of age in socioeconomically deprived populations. Both typhoid fever and paratyphoid fever occur in such areas, but paratyphoid fever is currently concentrated in South Asia. Typhoid conjugate vaccines are recommended for the control of enteric fever in typhoid-endemic settings; however, there are increasing demands for the development of vaccines that can address enteric fever more broadly by including protection against paratyphoid fever. The WHO preferred product characteristics (PPC) and a research and development (R&D) technology roadmap are normative documents developed with the guidance and contribution of a multidisciplinary expert group following a standard methodological framework. In this paper, we summarize the PPC and R&D roadmap presenting the key attributes for a bivalent Salmonella enterica serovar Typhi and Paratyphi A vaccine, and discuss the identified key research and data gaps needed to optimize vaccine value and to inform public health and policy decisions, with a particular focus in paratyphoid and enteric fever endemic countries.
Pilot study on the population genetics structure of Fasciola hepatica from seven provinces of South Africa
Nukeri , Sophy; Malatji , Mokgadi P.; Mnisi, Clearance M.; Chaisi, Mamohale E.; Mukaratirwa, Samson (Frontiers Media, 2025-09-11)
INTRODUCTION : Fasciolosis is a neglected tropical disease caused by Fasciola hepatica and Fasciola gigantica, affecting livestock, wildlife, and humans globally. Understanding the genetic diversity and population structure of Fasciola spp. is essential for tracking transmission patterns, detecting drug resistance, and guiding targeted control efforts. In South Africa, where such data are lacking, this study provides critical insights to support evidence-based interventions. This study aimed to assess genetic structure of Fasciola populations collected from cattle across seven provinces in South Africa. METHODS : Liver flukes were collected from 57 cattle from 13 provincial abattoirs across South Africa, and DNA was extracted from 189 F. hepatica specimens. Although sampling efforts varied slightly due to abattoir throughput, efforts were made to maximize geographic and ecological representation. Six polymorphic microsatellite loci were selected to assess genetic diversity based on their broad allelic range and prior validation for F. hepatica population genetic studies. The allele frequencies, Fis and Fst values, heterozygosity, and genetic distances were calculated on GenAlEx 6.51b2. Structure 2.3.4 was used to detect population structure. RESULTS : A total of 277 alleles were identified across loci, with allelic richness varying by province. All loci were polymorphic, and the mean number of alleles varied from 3.667 to 9.667. Moreover, out of the total number of alleles identified, 3% were private alleles. Observed heterozygosity (Ho) ranged from 0.182 to 1.000, while the expected heterozygosity (He) ranged from 0.165 to 0.899. These ranges suggest differences in genetic diversity and potential inbreeding or population structure across the samples studied. The fixation index (F) value ranged from −0.017 to 0.426. Fst values varied from 0.064 to 0.107, suggesting moderate genetic differentiation between the populations, and the number of migrants per generation (Nm) varied between 2.080 and 3.898, with an average of 3.173, which indicated a high gene flow between provinces. CONCLUSION : The Ho and He indicated moderate genetic diversity within populations, while the F-value showed moderate differentiation among populations. Geographic structuring of populations was observed, with the STRUCTURE and principal coordinate analysis (PCoA) revealing four distinct genetic clusters across seven provinces. Mpumalanga and Gauteng provinces displayed high genetic diversity and a high number of private alleles, suggesting potential reservoirs of genetic variation. Genetic distances varied by region, with neighboring provinces showing lower genetic distances, indicating gene flow and genetic connectivity across regions, which might be supported by the movement of livestock for trade. These findings highlight the genetic complexity and potential epidemiological challenges for fasciolosis in South Africa. Furthermore, considerable genetic diversity and gene flow across regions may complicate fasciolosis control and surveillance efforts in South Africa.
Management of dental disease in eared seals (family Otariidae) : a Delphi approach
Simeone , Claire A.; Schwitzer, Nora; Johnson, Shawn P.; Ruiz, José C. Almansa; Debosschere, Yves; Force, Judy; Forsayeth, Aaron; Gawor, Jerzy P.; Gracis , Margherita; Holmstrom, Steven; Legendre, Loïc; Mestrinho, Lisa A.; Sogorb, Arlete R.; Steenkamp, Gerhardus; Tucker , Rebecca; Tutt, Cedric; Urgel, Ignacio Velázquez; Woody, Allison (Frontiers Media, 2025-08-26)
OBJECTIVE : Published literature is sparse on topics associated with eared seal (otariid) dentistry. The objective of this study was to establish consensus on effective management of dental disease in otariids, using a Delphi approach. METHODS : A total of 25 veterinarians with experience managing dental disease in seven species of otariids participated in the Delphi process. RESULTS : Oral lesions and their contributing risk factors were ranked according to perceived frequency. Consensus statements for best practices were agreed upon for a variety of topics within the categories of planning and preparation, procedural details, intervention strategies, and postoperative care. Panelist comments were collated into a Supplementary File to assist clinicians in forming their own conclusions on topics for which no consensus yet exists. CONCLUSION : Opportunities for future research include factors associated with oral lesions, ideal anesthetic management, identification of ideal candidates for endodontic therapies, ideal local and regional anesthesia, ideal suture and closure techniques, particularly with the goal of reducing dehiscence as a postoperative complication, and ideal postoperative care options.
Spatial distribution and predictive risk of perpetuation of non-typhoidal salmonellosis in poultry farms and human communities: meta-analysis of data from Nigeria
Sanni, Abdullahi Ozomata; Jonker, Annelize; Johnson, Olatunji O.; Gayawan, Ezra; Shittu, Aminu; Fasanmi, Olubunmi G.; Adebowale, Oluwawemimo O.; Fasina, Folorunso Oludayo (Page Press, 2026-02)
To gain insight into the common pathogenic, bacterial zoonosis represented by Salmonella infections in poultry and humans, we acted to determine salmonellosis prevalence in poultry and humans in Nigeria mapping hotspots. Using multi-sourced data, we conducted a meta-analysis to determine national and sub-national prevalence of salmonellosis in poultry from 2000 until 2020. Bayesian spatial joint modelling was used to map Non-Typhoidal Salmonella (NTS) infections in humans and poultry using climatic and demographic predictor variables. With the overall prevalence in poultry at 31.6%, the highest state-level prevalence rates were seen in Ogun (70.2%), Lagos (61.8%), Zamfara (58.2%) and Bauchi (57.1%). The North-West, South-West and South-South regions of Nigeria have the highest regional-level prevalence in poultry amounting to 38.5%, 36.9% and 33.6%, respectively. Thirteen states have higher than the average national prevalence (31.6%). While we found a negative association between NTS in humans and in poultry, the prevalence of diarrhoea in humans positively predicted salmonellosis in poultry. Not surprisingly, poultry populations positively predicted salmonellosis in other poultry populations. Higher numbers of human cases were predicted in the North, with more poultry cases in the South and in some North-Eastern states. The observed human NTS-poultry salmonellosis correlation is counterfactual to logic and plausibility as high poultry density and contamination in poultry are expected to predict human infection. The outcome pointed to under-reporting linked to self-treatment, under-testing in the public health and veterinary laboratory and lack of uniform primary healthcare services, particularly in under-served areas of Nigeria. Salmonellosis continues to be a serious burden, and provision of better health data is needed.
Serological and virological evidence of MERS-CoV infection among dromedary camels in Africa: a systematic review and Meta-analysis
Gaddafi, Mohammed Sani; Lawal, Habiba; Musawa, Ibrahim Aliyu; Garba, Bashiru; Goni, Mohammed Dauda; Jolayemi, Kelvin Olutimilehin; El-Yakub, Abdulgaffar Usman; Jibril, Abdulrahman Hassan; Saeed, Shamsaldeen Ibrahim; Bitrus, Asinamai Athliamai; Salman, Maryam; Fasina, Folorunso Oludayo; Yakubu, Yusuf (Springer, 2026-02)
Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is a zoonotic pathogen of major public health concern due to its pandemic potential. Dromedary camels are the principal reservoir, and Africa harbors over 60% of the global dromedary population. This systematic review and meta-analysis assessed the serological, molecular, and geographical distribution of MERS-CoV infection and associated risk factors among African dromedary camels over the past decade. A systematic search of Web of Science, PubMed, Scopus, and African Journals Online (AJOL) was conducted for studies published between 2012 and 2025, following PRISMA 2020 guidelines. Thirty-nine eligible studies from 13 African countries were included, predominantly from East Africa, followed by North and West Africa. The pooled seroprevalence and viral RNA prevalence of MERS-CoV among dromedaries were 75.1% (95% CI: 68.2%-82.0%; I2 = 99.4) and 6.2% (95% CI: 3.5%-8.9%; I2 = 99.7), respectively, indicating extensive exposure history. Subgroup analysis showed regional variation, with the highest pooled seroprevalence in North Africa and highest viral RNA prevalence in West Africa (5.5%). Adult camels had higher seroprevalence (78.5%) than juvenile camels (42.5%), while viral RNA detection was slightly higher in young (5.5%). Female camels showed slightly higher (descriptive) pooled seroprevalence (69.7%) than males (65.8%), whereas males had slightly higher pooled viral RNA prevalence (5.1%) compared to females (4.0%). Nine studies examined human infection among camel handlers, yielding a pooled prevalence of 12.3% (95% CI: 1.4%-25.9%; I2 = 99.9). These findings highlight widespread MERS-CoV circulation in African camels and the urgent need for coordinated One Health surveillance to mitigate zoonotic risks.
The continental distribution of Theileria and Babesia species in African wild mammals : a systematic review and meta–analysis of molecular prevalence
Cossu, Carlo Andrea; Blignaut, Coenraad; Bhoora, Raksha Vasantrai; Neves, Luís C.B.G.; Smit, Andeliza; Sibeko-Matjila, Kgomotso Penelope; Morar-Leather, Darshana; Collins, Nicola E.; Oosthuizen, Marinda C.; Van Heerden, Henriette (Elsevier, 2026-05)
Tick–borne piroplasmids of the genera Theileria and Babesia are emerging threats at the wildlife–livestock–human interface, particularly in Africa, where ecosystems are rapidly changing due to anthropogenic pressures. This systematic review and meta-analysis synthesizes current knowledge on their occurrence and molecular prevalence of these piroplasmids in African wild mammals. A total of 56 studies met the inclusion criteria, identifying 24 recognized species of Babesia and Theileria species, along with an additional 17 species that have provisional/uncertain denomination across nine African countries. Of these, 47 studies were suitable for meta-analysis, revealing a high overall molecular prevalence of Theileria/Babesia spp. in wild mammals (62.4 %; CI: 39.3–82.8 %), with Babesia spp. generally more prevalent in wild carnivores, while Theileria spp. predominated in wild ruminants. In African buffalo (Syncerus caffer), pooled prevalence of T. parva, the agent of East Coast fever and Corridor disease, was estimated at 62.9 % (CI: 37.5–85.0 %), with significant geographic differences. Babesia bovis, the most pathogenic agent of bovine babesiosis, was rare in buffalo (0.4 %; CI: 0–6.5 %), whereas the less pathogenic B. occultans reached 23.3 % (CI: 16.2–31.3 %) in the same species and 30 % (CI: 15.2–47.3 %) in blue wildebeest (Connachaetes taurinus). Zoonotic B. microti was detected in non-human primates, wild felids, and rodents, and a B. odocoilei–like organism was identified in lions (Panthera leo). Our findings underline the ecological complexity and hidden burden of piroplasms in African wildlife and the potential for spillover to domestic animals and humans. This review provides the first continental-level synthesis of Theileria and Babesia distribution in African wild mammals and emphasizes the need for expanded and enhanced molecular monitoring in underrepresented countries and animal taxa, as well as extensive taxonomic clarification. HIGHLIGHTS • First systematic review of Theileria and Babesia in African wild mammals, covering 56 studies across nine countries. • Identified 24 recognized piroplasmid species and 17 provisionally named taxa, highlighting substantial taxonomic gaps. • Molecular prevalence of piroplasms was 62.4%. Babesia dominated carnivores, Theileria ruminants. T. parva in buffalo 62.9%. • Detection of B. bovis in buffalo, B. occultans and zoonotic B. microti in non-human primates, wild felids and rodents. • Need for expanded molecular surveillance and taxonomic clarification of piroplasmid burden in African wildlife.
Elevated IL-6, IL-10, and IFN-g levels in fatal elephant endotheliotropic herpesvirus – hemorrhagic disease cases suggest an excessive proinflammatory cytokine response contributes to pathogenesis
Hoornweg, Tabitha E.; Schaftenaar, Willem; IJzer, Jooske; Mulder, Myrna M.P.; Lugtenburg, Mariska; Van Beest, Anne; De Haan, Cornelis A.M.; Rutten, Victor P.M.G. (Frontiers Media, 2025-10-27)
INTRODUCTION : Hemorrhagic disease developed as a consequence of an EEHV infection (EEHV-HD) is the leading cause of death of young Asian elephants in Zoos worldwide and also affects elephants in range countries. Although a cytokine storm has long been suggested to underlie disease pathogenesis, there is little evidence and the role of cytokines in EEHV-HD pathogenesis remains unclear to date. METHODS : In the current study, we compared mRNA levels of eight different cytokines between blood and tissue samples of EEHV-HD cases (n=11) and controls (n=12) in order to determine whether cytokines may contribute to EEHV-HD pathogenesis. RESULTS : We show the presence of significantly elevated mRNA levels of IFN-γ, IL-6 and IL-10, cytokines typically associated with cytokine storms, in blood or tissues with high viral loads (heart and liver) of EEHV-HD cases. Comparable cytokine inductions were not observed in tissues with lower viral loads (tongue, lung and kidney), indicating an association between viral replication and cytokine induction, and suggesting damage observed in these tissues is likely collateral. DISCUSSION : In conjunction with pathological findings, including acute systemic inflammation and multiple organ dysfunction, we propose that a pathogen-induced cytokine storm indeed underlies EEHV-HD pathogenesis, which would support investigation into the use of anti-inflammatory therapies to control disease.
Knowledge, attitudes, and practices of abattoir workers about Taenia solium cysticercosis in the Eastern Cape Province, South Africa
Sibutha, Siziwe; Byaruhanga, Charles; Jaja, Ishmael Festus (Wiley, 2026-06)
The tapeworm, Taenia solium, is the cause of cysticercosis, a neglected zoonotic disease that poses a significant global threat to animal and public health. Data were collected between May and June 2024 using a structured, interviewer-administered questionnaire (n = 152) comprising demographic items and sections on knowledge, attitudes, and practices. The knowledge section included basic conceptual questions such as “Have you ever heard about the word zoonosis?” and disease-specific items such as “Taenia solium can be contracted through the consumption of undercooked pork Yes or No?” Additional questions assessed recognition of cysts, understanding of transmission pathways, and hygiene and inspection practices relevant to daily work routines. This is important for disseminating knowledge about prevention measures among communities. Most respondents were unfamiliar with the disease, with only 12.5% (n = 19) demonstrating a good understanding of the source and transmission of T. solium. The attitudes of the workers were negative or just moderate (63.2%), specifically toward hygiene in the abattoirs, personnel training, and the fate of infected carcasses. However, a good level of practice (90.2%) was achieved regarding sanitation and disposal of condemned carcasses, which can be attributed to management regulations rather than workers' concerns. There is a need to enhance awareness among abattoir workers about the public health and economic consequences of T. solium infection, thereby improving their knowledge of the disease and its transmission. This can be beneficial to the rest of the community, especially pork consumers, in preventing the continuous spread of cysticercosis. PLAIN SUMMARY This research examined the level of knowledge among slaughterhouse workers in South Africa regarding Taenia solium, a tapeworm that can lead to severe illness in pigs and humans. Humans and animals contract infections by consuming food or water that contains the parasite's eggs. Given that abattoir workers frequently manage pork, they must understand how the disease transmits and the methods to avert it. To gain further insights, we distributed questionnaires to 152 employees in the Eastern Cape Province. Most of them had minimal knowledge about the disease, with only a few demonstrating a solid understanding. We additionally discovered that age, gender, or education did not influence their level of knowledge. The findings indicate a critical requirement for training initiatives to assist abattoir employees in comprehending and mitigating the transmission of this detrimental illness. CORE IDEAS • Abattoir workers play a crucial role in the detection and prevention of Taenia solium transmission due to their involvement in pork processing. • Lack of formal training on zoonotic diseases and food safety presents a barrier to disease control. • Targeted educational interventions are urgently needed to improve workers’ understanding and practices related to T. solium, thereby reducing risks to public and animal health.
A review of rabies in Southern African wildlife : reservoir hosts, transmission dynamics, and control implications
Eze, Ukamaka Uchenna; Sabeta, Claude Taurai (Eldaghayes Publisher, 2026-01)
Rabies is a fatal zoonotic disease that affects warm-blooded vertebrates and is caused primarily by members of the Lyssavirus genus (family Rhabdoviridae, order Mononegavirales). Three Lyssavirus species, namely Lyssavirus duvenhage and the putative lyssaviruses Lyssavirus matlo and Lyssavirus phyla, were first identified in insectivorous bat species in South Africa through lyssavirus surveillance activities. For the proposed and effective global elimination of dog-mediated human rabies by 2030; it is important to contextualize the pivotal role of wildlife in the maintenance and the likely spillover of rabies virus infections into naive dog populations that could potentially derail the progress toward rabies elimination. This review on rabies in wildlife identifies the current reservoir host species for sylvatic rabies, species predominantly affected by rabies (and non-rabies lyssaviruses) in southern African wildlife, and rabies transmission dynamics between these species. Canid rabies is maintained in a variety of southern African wildlife carnivores, including the black-backed jackal species (Canis mesomelas), side-striped jackals (Canis adustus), bat-eared foxes (Otocyon megalotis), and most recently, aardwolves (Proteles cristatus). In addition, the yellow mongooses (Cynictis penicillata) and slender mongooses (Galerella sanguinea) are reservoirs of the mongoose rabies virus (RABV) biotype (in South Africa and Zimbabwe, respectively). In Namibia, rabies virus infection is associated with wild ruminants, especially the kudu antelope (Tragelaphus strepsiceros), thereby posing a conservation threat to specific wildlife species. Oral rabies vaccination of wild carnivores using baited vaccines has been used as a complementary approach to mass dog vaccinations to mitigate infection spillover into domestic host species.
A systematic review and meta-analysis of mosquito arboviral infections detected through xenosurveillance in Africa : a focus on West Nile, Rift Valley fever, and chikungunya virus infections
Mgongoma, Mxolisi; Bastos, Armanda D.S.; Ramoelo, Abel; Tchouassi, David Poumo (Elsevier, 2026)
This systematic review and meta-analysis comprehensively evaluated the mosquito arboviral infections with West Nile virus (WNV), Rift Valley fever virus (RVFV), and chikungunya virus (CHIV), detected through xenosurveillance, reported in mosquito vectors across Africa in the last 25 years (2000–2024). The study analysed xenosurveillance data from 45 studies conducted with over 115,000 mosquito specimens, and incorporated moderator analyses to assess the influence of trap type, seasonality, regional location, settlement type, and screening methods on virus detection rates. The estimated pooled prevalence of WNV was 1.18% (95% CI: 0.60–3.43%), with higher rates observed in Culex quinquefasciatus and Culex pipiens, particularly in Northern Africa. RVFV prevalence was 2.00% (95% CI: 0.96–4.52%), with notable detections in Cx. tritaeniorhynchus and Aedes mcintoshi in Eastern Africa. Pooled prevalence was highest for CHIV (8.00%, 95% CI: 2.92–22.25%), primarily in Ae. aegypti and Ae. albopictus in Central and Eastern Africa. In meta-regression analysis, qRT-PCR and indirect immunofluorescence were identified as screening methods associated with higher WNV detection, while wet season sampling and CDC light traps were linked to elevated RVFV prevalence. There was substantial heterogeneity (I2 > 97%) in regional and methodological approaches. The disparities underscore the need for standardised xenosurveillance protocols, region-specific strategies, and enhanced diagnostics to mitigate arboviral risks in Africa. Limitations included sparse CHIV data and underrepresentation of studies from Southern and Central Africa, emphasising the need for expanded longitudinal and geographically inclusive research. HIGHLIGHTS • Pooled WNV prevalence was 1.18%, with higher values for Cx. quinquefasciatus and Cx. pipiens in Northern Africa. • Pooled RVFV prevalence was 2.00%, primarily in Cx. tritaeniorhynchus and Ae. mcintoshi in Eastern Africa. • CHIV showed the highest pooled prevalence, mainly in Ae. aegypti and Ae. albopictus in Central and Eastern Africa. • qRT-PCR and indirect immunofluorescence were screening methods associated with higher WNV detection in mosquitoes. • Wet season sampling using CDC light traps was associated with elevated RVFV prevalence.
Citizen scientists for moveApps : innovations and insights from volunteer coders in wildlife conservation
Kolzsch, Andrea; Safi, Kamran; Armfield, Margaux M.; Beaupre, Chloe; Bennitt, Emily; Bock, Matthias; Brown, William; Eichler, Christoph; Fielder, Wolfgang; Hahn, Clemens; Jain, Varalika; Ketchin, Matthew W.; Long, Jed A.; Merdian-Tarko, Alexander V.; Minchin, Lauren; Neves de Matos, Tomé; Rakesh, Ambati; Van Schalkwyk, Ockert Louis; Wikelski, Martin; Scharf, Anne K. (Wiley, 2025-08)
Amidst numerous global crises, decision-makers have recognized the critical need for fact-based advice, driving unprecedented data collection. However, a significant gap persists between data availability and knowledge generation, primarily due to time and resource constraints. To bridge this gap, we propose involving a novel group of citizen scientists: volunteer code developers. 2. Utilizing the modular, open-source analysis platform MoveApps, we were able to engage 12 volunteer coders in a challenge to create tools for movement ecology, aimed at animal conservation. These volunteers developed functioning applications capable of analysing animal tracking data to identify stationary behaviour, estimate ranges and movement corridors and assess human–wildlife conflicts using data sets from human infrastructure, such as OpenStreetMap. 3. Engaging citizen scientists in developing code has surfaced three primary challenges: (i) Community Building—attracting the right participants; (ii) Community Involvement—maintaining quality standards and directing tasks effectively; and (iii) Community Retention—ensuring long-term engagement. We explore strategies to overcome these challenges and share lessons learnt from our coding challenge experience. Our approaches include engaging the community through their own preferred channels, providing an accessible open-source tool, defining specific use cases in detail, ensuring quality through feedback, fostering self-organized community exchanges and prominently illustrating the impact of contributions. 4. We also advocate for other disciplines to consider leveraging volunteer involvement, alongside artificial intelligence, for data analysis and generating state-of-the-art, fact-based insight to address critical issues such as the global decline in biodiversity.
Extraction of saliva, haemolymph, salivary glands, and midgut from individual ticks (Acari: Ixodidae)
Khogali, Rua Khogali Ibrahim; Getange, Dennis; Bastos, Armanda D.S.; Masiga, Daniel; Villinger, Jandouwe (MyJove Corporation, 2025-10-31)
Ticks are blood-feeding ectoparasites recognised for their ability to transmit several infectious pathogens to humans and animals. Tick-borne pathogen (TBP) surveillance generally relies on detecting pathogens in homogenates of entire ticks, including those acquired during blood feeding, which may not be transmitted by the tick. To better understand the pathogen transmission mechanism, it is essential to investigate the dissemination and concentration of TBPs in various tick tissues, which is important for elucidating transmission mechanisms in ticks and determining their vector competence. This, in turn, rests on procedures for isolating saliva, haemolymph, salivary glands, and the midgut of individual ticks in order to examine the location of TBPs within these tissues and fluids. In this study, we describe a protocol for tick tissue collection, including a novel procedure for the collection of haemolymph. The results confirm that Rickettsia africae occurs at higher levels in the haemolymph of Amblyomma gemma, affirming the likely role of this tick species as a competent vector for R. africae. In contrast, Hyalomma dromedarii exhibited high rates of R. africae in the midgut, but the bacterium was absent in the haemolymph. The presence of TBPs in the haemolymph is therefore a valuable indicator of vector competence, and rests on the availability of a method that ensures ease of collection.
Multi-locus sequence analysis of Anaplasma in the common warthog (Phacochoerus africanus) from South Africa
Rea, Keaton; Buss, Peter Erik; Bastos, Armanda D.S. (Elsevier, 2025-12)
The prevalence and diversity of Anaplasma in common warthog (Phacochoerus africanus) was investigated using a multi-locus sequence analysis (MLSA) approach targeting the 16S rRNA, citrate synthase (gltA) and heat-shock operon (groESL) genes. PCR screening of 100 warthog samples from the Kruger National Park in South Africa with eight published assays identified 50 positive animals, all of which were initially identified with the 16S rRNA assay. In contrast, the gltA and six groESL assays recovered PCR-positivity rates of 2 % and 0 %-4 %, respectively. As optimisation did not improve Anaplasma detection rates, an alternative groESL assay targeting a 923 bp region was designed. This new assay detected 45 positive animals, all of which were positive with the 16S rRNA assay. Nucleotide sequencing of the three MLSA gene targets confirmed that 50 % (50/100) of warthogs were Anaplasma-positive. Juvenile warthogs displayed a significantly higher infection rate (15/18; 83.3 %) than adults (35/82; 42,68 %). Phylogenetic analyses of individual and concatenated gene datasets confirmed that the Anaplasma species in warthogs is closely related to the species detected in Ornithodoros soft ticks from Zambia. This, together with the high levels of nucleotide sequence identity (≥98.97 %), suggests the likely existence of a host-restricted cycle involving warthogs and the soft ticks that inhabit their burrows. Based on the distinctiveness and monophyly of the Anaplasma species in warthogs and Ornithodoros soft ticks, confirmed through genetic characterisation of three gene regions, we propose that Candidatus status be assigned and suggest “Candidatus Anaplasma ornithodorii”. HIGHLIGHTS • Overall sequence-confirmed Anaplasma prevalence of 50 % in warthogs. • Three gene regions (16S rRNA, gltA and groEL) were characterised. • Anaplasma species in warthogs matches species detected in Ornithodoros soft ticks.
The optimisation and application of a novel baseScope™ RNA-ISH assay for the detection of foot-and-mouth disease virus in carrier African buffalo (Syncerus caffer) from South Africa
Henning, Alischa; Odendaal, Lieza; Loots, Angelika Katrin; Quan, Melvyn (Elsevier, 2025-12)
The detection of foot-and-mouth disease is limited to BSL-3 laboratories and its detection in carrier animals require increased test sensitivity. In-situ-hybridisation utilises the propensity of a labelled single-stranded sequence of DNA or RNA to anneal to a complementary target. It can be performed on formalin-fixed tissues and with some of the most recent advances, show an increased test sensitivity. BaseScope™ incorporates an additional signal amplification step, which makes it possible to detect RNA splicing variants, point mutations, small insertions or deletions, and short RNA targets (50–300 nucleotides). This study aimed to adjust and optimise the BaseScope™ assay to detect foot-and-mouth disease virus in a novel, carrier wildlife species, i.e., buffalo. Specific steps were adjusted to attempt to address some of the rigidity involved in the workflow. However, none of the in-house reagents or equipment attempted as an alternative to the original and prescribed workflow was successful. This demonstrates the fastidious nature of this diagnostic modality and the synergistic characteristics of a commercial assay. However, keeping tissues in formalin for up to 7 days and storing cut sections for up to 3 months did not have a negative impact on the results. This further demonstrated the reliability of BaseScope™.
Innate resistance to African swine fever virus : current knowledge and future directions
Auer, Agathe; Blome, Sandra; Rozstalnyy, Andriy; Penrith, Mary-Louise (BioMed Central, 2026-01)
This review explores the biological basis and epidemiological implications of natural resistance to ASFV. It dispels the misconception that African wild suids are persistent virus reservoirs and clarifies the role of Ornithodoros ticks in virus maintenance and transmission. Resistance mechanisms appear multifactorial, potentially involving host genetics and immune responses. Genomic studies have begun identifying genes potentially linked to ASFV resistance, including in pigs from areas with more recent ASF incursions. Understanding and harnessing natural resistance is a promising avenue to develop ASFV-resilient pig populations, especially for smallholder farmers in resource-limited settings. While vaccines remain limited, promoting and protecting naturally resistant pigs offers an immediate, practical tool to mitigate the impact of ASF in endemic regions.
In vitro monitoring of Babesia microti infection dynamics in whole blood microenvironments
Li, Chao; Bache, Emily G.; Apgar, Amy L.; Tufts, Danielle M.; Niepa, Tagbo H.R. (Wiley, 2025-11)
Babesiosis – a globally emerging tick-borne infectious disease primarily caused by the intraerythrocytic piroplasm parasite, Babesia microti – has traditionally been studied using animal models such as mice. Compared to animal models, microﬂuidic-based models oﬀer advantages, including direct analysis of human samples (such as patient blood), enhanced assay capacity (including physical/optical access, consistency, and throughput), low costs, and easy adoption. Here, an open microﬂuidic platform named “µ-Blood” is reported for real-time continuous monitoring B. microti infection dynamics invitro. Compared to other microﬂuidic-based models, µ-Blood allows direct examination of infected and uninfected whole blood without preprocessing steps like blood dilution or cell isolation, minimizing observer artifacts and preserving the natural whole blood microenvironment. The system enables extended (72 h) monitoring of infection dynamics, including parasite identiﬁcation, parasitemia measurement, and parasite–host cell interactions, using label-free phase contrast and ﬂuorescence confocal microscopy. With its open microﬂuidic conﬁguration, µ-Blood provides an in vitro model for studying blood-borne infection dynamics while maintaining integrity of the whole blood microenvironment.
Husbandry practices among peri-urban free-roaming pigs in Gert Sibande District Municipality, Mpumalanga, South Africa
Makungo, Priscilla; Fasina, Folorunso Oludayo; Mbajiorgu, Christian Anayochukwu; Oguttu, James Wabwire (University of Kassel, 2025-09-15)
Interactions at the human-animal-environment interface have increased significantly as a result of globalisation, increased urbanisation, environmental degradation and the growing need for animal-based foods, leading to the growth of peri-urban agriculture. We investigated peri-urban free-roaming pig (FRP) production husbandry practices to identify production constraints in a district municipality in South Africa. Pig farmers (n=124) were identified using snowball technique and interviewed. Statistical analyses were performed using SPSS V28.0. Most of the FRP farmers were men (70.2%), aged ≥ 36 years (80.7%), and individuals with ≤ high school education (84.6%). The majority (75.8%) did not have a weaning protocol, and a large proportion (93.5%) conducted peri-urban FRP without permission from the local authority and were not registered for animal identification (72.6%). Over 94.4% of the farms didn’t employ routine disinfection and were unaware of transboundary animal diseases and zoonosis (87.1%). Most pigs in the study area (72.5%) were exotic breeds, or their crosses and most sows (51.6%) farrowed 6-10 piglets per litter. Exotic breeds or their crosses weaned larger litters (>11) compared to indigenous breeds. Pigs scavenging in residential areas had a significantly higher risk of theft and accidents. The widespread poor husbandry practices among FRP farmers provides an opportunity to develop tailored risk communication and community engagement materials for farmers and communities. Municipalities should adopt a fit-for-purpose peri-urban livestock policy, with clear incentives and penalties to promote animal identification and good practices. Given the potential for pigs to spread disease to humans, good practices will reduce the risk of humans contracting diseases from animal-derived food.

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