Journal of Vector Borne Diseases

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Canine leishmaniasis in Maghreb countries: A systematic review and meta-analysis
(Wolters Kluwer – Medknow, 2024-12) Baaziz, Sabrina; Sadeddine, Rima; Zeroual, Faycal; Benakhla, Ahmed; Righi, Souad
Canine leishmaniasis (CanL) is a zoonotic disease caused by infection with Leishmania infantum and transmitted by female phlebotomine sandflies. It is prevalent in the Mediterranean basin, including the Maghreb region which comprises of Algeria, Tunisia, and Morocco. The environmental conditions in this area provide a suitable habitat for the proliferation of the phlebotomine sandfly, making it an endemic region for CanL. In this context, we carried out a systematic review and meta-analysis on the prevalence of canine leishmaniasis in these three Maghreb countries, identifying the risk factors for L. infantum infection. Data were collected from 27 papers published between 1973 and 2022 selected from five databases: PubMed, Google Scholar, ResearchGate, ScienceDirect and Scopus. Our selection criteria included both descriptive and analytical studies on canine leishmaniasis in Maghreb, as well as epidemiological studies that reported the prevalence of leishmaniasis infection. The meta-analysis was performed using Review Manager (RevMan) software version 5.4.1. based on predefined inclusion criteria. A total of 11,736 dogs were included in the analysis, among which 2481 were tested Leishmania positive cases. Over the years, the highest prevalence (68.32%) was recorded in Tiaret (Algeria) and the lowest (4.3%) in Tunisia. The examination of the risk factors revealed a heightened incidence of the disease in dogs of shepherd breeds, living in rural environ- ments, displaying no apparent symptoms, and falling within the age range of 2 to 4 years. The findings presented in this study contribute a significant value to the exploration of leishmaniasis in this region, particularly by shedding light on the associated risk factors. Ultimately, substantial endeavors are warranted to enhance prevention, treatment, and overall control of the disease.
Computational design, docking, and molecular dynamics simulation study of RNA helicase inhibitors of dengue virus
(Wolters Kluwer – Medknow, 2024-12) Satpathy, Raghunath; Acharya, Sonali; Behera, Rashmiranjan
Background & objectives: RNA viruses are complex pathogens in terms of their genetic makeup, mutation frequency, and transmission modes. They contain the RNA helicase enzyme, which plays a crucial role in the viral genome replication process. This work aims to develop and screen a potential molecule that could function as a dengue virus (DENV) RNA helicase inhibitor. Methods: The present study was performed by taking 26 potential derivatives of gedunin phytochemicals from the PubChem database as ligands. The binding of the compounds was analyzed by in silico docking considering DENV RNA helicase enzyme as the receptor. Results: After a thorough analysis of the docking scores, toxicity, and physicochemical properties, the compound tetrahydrogedunin was obtained as the best. Based on tetrahydrogedunin molecular structure, 100 drug-like molecules were designed using the Data Warrior tool. After screening for drug-likeness and ADMET properties, derivative number 42 was considered as promising. Further comparative docking of derivative 42 and a standard inhibitor molecule ST-610 with DENV RNA helicase enzyme showed binding affinity of 10.0 kcal/mol and -9.6 kcal/mol, respectively. The favorable interaction between DENV RNA helicase and derivative 42 was further validated by 50 nanoseconds molecular dynamics simulation and MM-GBSA analysis. Interpretation & conclusion: Since the antiviral activity of derivative 42 has not been reported till date, the compound was predicted as a novel therapeutic molecule that can act against the dengue virus (DENV) RNA helicase enzyme.
Chemical composition and mosquitocidal activity of methanolic leaf extracts from Ziziphus mauritiana L. against Aedes aegypti L. and Culex quinquefasciatus Say
(Wolters Kluwer – Medknow, 2024-12) Sumathi, Ganesan; Pushpanathan, Thambusamy; Abhirami, Muthukumar
Background & objectives: Mosquito vectors are a significant cause of pathogen transmission to both animals and humans. Mosquitoes are responsible for transmitting various diseases, including chikungunya, filariasis, West Nile fever, dengue, malaria, and Zika fever, placing approximately 80% of the world’s population at risk of infection at any given time. Controlling mosquitoes has become a multifaceted challenge, influenced by diverse environmental factors such as deforestation, urbanization, and climate change on a global scale. For centuries, medicinal plants have been utilized as bioinsecticides to control insect pests. Ziziphus mauritiana, also known as Chinese apple or Indian jujube is a deciduous thorny tree or shrub. Different parts of the Z. mauritiana plant have been traditionally used to treat various common diseases, a practice still prevalent in India and China. Methods: In the current investigation, the chemical properties of Z. mauritiana leaf extract were examined through UV-Vis Spectroscopy, Fourier Transform Infra-Red Spectroscopy (FTIR), and GC-MS Analysis. Second and fourth instar larvae, as well as pupae, of Aedes aegypti and Culex quinquefasciatus were subjected to different concentra- tions of the methanolic extract of Z. mauritiana for 24 h and 48 h to assess larvicidal and pupicidal activity. Results: The FT-IR spectrum analysis revealed the presence of various functional groups in the chemical com- pounds extracted from Z. mauritiana, including amines, aromatics, alkanes, alkyls, carbonyls, and carboxylic acids. Additionally, GC-MS analysis identified Isoborneol (25.37%), 4-Acetylbutyric Acid (26.82%), and 2-Vinyl- 9-[Beta-D-Ribofuranosyl] Hypoxanthine (24.24%) as the three major phytoconstitutents in the methanol extracts of Z. mauritiana. Regarding the larvicidal activity, the methanolic extract of Z. mauritiana exhibited LC50 values of 155.67 mg/L and 208.57 mg/L for second instar larvae, and 177.68 mg/L and 252.13 mg/L for fourth instar larvae of Cx. quinquefasciatus and Ae. aegypti, respectively, after 24 h of exposure. For pupicidal activity, the LC50 values were 502.02 mg/L and 514.99 mg/L on pupae of Cx. quinquefasciatus and Ae. aegypti, respectively, within 24 h. Interpretation & conclusion: Overall, the GC-MS analysis provides valuable insights into the chemical composition of the Z. mauritiana extract, highlighting its potential as a natural and eco-friendly alternative for combating insect vectors and contributing to integrated mosquito management programs.
Outcome assessment of the implementation of Mass Drug Administration against lymphatic filariasis in Kalaburagi (Gulbarga) Karnataka, India: A cross-sectional survey
(Wolters Kluwer – Medknow, 2024-12) Babu, Puttamaligaiah Subhas; Goud, Bhoompuram Nagaraja; Kambale, Shambhulinga B
Background & objectives: Mass Drug Administration (MDA) of Di-Ethyl Carbamazine and Albendazole is an ef- fective strategy recommended by the World Health Organization to prevent transmission and eliminate lymphatic filariasis. Under the National Vector Borne Disease Control Programme (NVBDCP) in India, MDA is carried out as a yearly activity in endemic areas to accelerate the progress towards elimination of lymphatic filariasis. The study was carried with the objective to determine the coverage of MDA against lymphatic filariasis among the eligible population in Kalaburagi district, Karnataka and delineate the common reasons for non-acceptance of MDA. Methods: Field-based cross-sectional survey was carried out. Cluster sampling of 4 clusters (3 rural and 1 urban) from four different taluks (one cluster from each taluk) of the district reporting high, medium and low coverage of MDA (as reported by District Malaria Office) Members from selected households in all clusters were interviewed regarding MDA administration, directly observed treatment, side effects and any co morbidities which ruled out MDA administration. Responses documented as tally marks in assessment sheets shared by NVBDCP office. Proportions, frequencies, and mean were calculated and inferential statistics were used. Results: A total of 1263 individuals were assessed for MDA from a total 240 households (60 households in each cluster). The coverage of MDA varied from 90.33% in Heerapur in Kalaburagi Urban to 97.87% in Mogala thanda (Chittapur Taluk). Interpretation & conclusion: MDA Coverage against lymphatic filariasis has improved when compared to previous studies and it has also exceeded the coverage threshold as determined by programme for elimination of lymphatic filariasis.
Social, behavioral and environmental determinants of vector-borne diseases: A narrative review of evidence and implications for integrated control approaches
(Wolters Kluwer – Medknow, 2024-12) Alqassim, Ahmad Y
Vector-borne diseases exert immense health burdens worldwide. Malaria alone causes over 200 million cases and 600,000 deaths annually. Transmission involves complex drivers requiring examination beyond entomological factors. A systematic literature search across databases identified relevant studies on vector-borne disease determinants published in the last two decades, with priority given to rigorous designs like longitudinal analyses, reviews, and meta-analyses from diverse epidemic regions, allowing narrative synthesis of key determinants, relationships, and gaps. This narrative review synthesizes evidence on social, behavioral, and environmental determinants of major vector-borne disease risks over the past decade. Lower education, poverty, unplanned urbanization, gender inequities, inadequate water and waste management, climate variations, and land-use changes stood out as key determinants. However, significant knowledge gaps remain around quantifying precise threshold effects and impacts of tailored interventions across contexts. A social-ecological perspective recognizing interdependencies between determinants should frame integrated control programs. Multicomponent strategies addressing environmental modifications, protective measures, behavioral motivators, and infrastructure alongside governance and community engagement require implementation research and impact evaluation. Overall, this review highlights priority areas for advancing evidence-based vector control through contextualized, determinant-targeted policies and interventions. Further research incorporating modeling, trials, and cost-effectiveness analyses is critical to validate approaches that address influential drivers, leverage motivators, and reduce the global burden.
Aedes aegypti oviposition in urban communities in the Northern Chihuahuan Desert
(Wolters Kluwer – Medknow, 2024-12) Vera, Adam J; Soliz, Albert G; de la Mora-Covarrubias, Antonio; Watts, Douglas M
Background & objectives: Aedes aegypti (Linnaeus) is the vector of multiple arboviruses, the most important being dengue viruses (DENV) that causes more than 90 million cases per year. The expanded range of Ae. aegypti into temperate climates has contributed to the increasing risk of DENV to new human populations. As an effort to better understand the ecology of Ae. aegypti in a temperate climate, larval surveillance was conducted to identify oviposi- tion locations of this species from 2016–2018 in two nonincorporated communities located in El Paso, Texas and Ciudad Juárez, Chihuahua, Mexico. Methods: This survey was conducted inside and outside private residences examining any possible water holding containers to collect with a dipper, turkey baster, or Pasteur pipette. Larvae and pupae were transported to the labo- ratory and reared to adults for morphological identification. A total of 601 Ae. aegypti larvae were collected and reared to adults from 24 containers in the Sparks community. In contrast, a total of 68 Ae. aegypti were collected and reared to adults from seven containers in the Anapra community. Results: In both locations, the predominant container type that yielded immature mosquitoes were plastic buckets. Although the results were based on a small sample size, the finding provided a preliminary understanding of the oviposition sites of Ae. aegypti in two urban communities in a temperate climate region. Interpretation & conclusion: The identification of oviposition sites can be used to develop and implement vector control strategies.
Single jar for collecting and rearing mosquito life stages: An innovative prototype
(Wolters Kluwer – Medknow, 2024-12) Kachhwaha, Neetu
Background & objectives: Mosquitoes vectors are the key threat that spread viruses, bacteria, nematodes, protozoans, and other infections responsible for the transmission of serious public health ailments including dengue, yellow fever, malaria, and chikungunya. Methods: To rear and cultivate mosquitoes at multiple stages of development (egg, larva, pupa, and adult) to be employed in various biomedical research, an innovative tool mosquito larva adult 2-in-1 rearing jar was designed and developed. The eggs/larvae or adults collected from the field or laboratory cultures can be released into the lower larvae or upper adult-rearing chamber so that they can find a suitable breeding place to oviposit or metamorphose into wrigglers and tumblers attaining the adult stage. Aedes, Anopheles, and Culex are three significant genera (Diptera: Culicidae) that were reared in experiments using this jar (Method I) in contrast to other conventional instruments available (Method II). Results: Results of one-way ANOVA showed that the prototype was compatible and competitive for rearing, as the data was non-significant when compared in both groups. However, throughout the trials, it was discovered that the prototype had a greater record of mean percentage of adult emergence (98.33), which supports the novelty of the instrument. Interpretation & conclusion: This unique device eliminates the need for multiple tools, causes minimum bodily damage to stages during handling, can be used in both the lab and the field, is inexpensive, lightweight, portable, and requires single manpower to operate.
Asymmetrical reproductive interference between Aedes aegypti and Aedes albopictus: Implications for coexistence
(Wolters Kluwer – Medknow, 2024-12) Hasan, Tanvir; Afrin, Sadia; Sultana, Afroza; Islam, Ashekul
Background & objectives: Aedes aegypti and Ae. albopictus are two sympatric mosquito species that compete with each other for resources when their breeding habitats overlap. This study examines what happens when sympatric Ae. aegypti and Ae. albopictus mosquitoes’ mate with each other and other species by looking at insemination rates, fecundity, and hatchability rate. Methods: We performed controlled mating experiments in laboratory settings, assessing both conspecific and inter- specific crosses. We measured insemination rates, egg numbers, and hatching success to examine the reproductive interference dynamics between these two distinct mosquito species. Results: In the context of conspecific mating, it was observed that both female Ae. aegypti and Ae. albopictus exhib- ited high insemination rates, with percentages 98% and 94%, respectively. However, interspecific mating exhibited interesting asymmetries as Ae. albopictus males achieved a notable insemination success rate of 28% when mating with Ae. aegypti females, while Ae. aegypti males achieved only an 8% insemination success with Ae. albopictus females. Additionally, females that mated with interspecific males had reduced production of viable eggs compared to conspecific mating. Most notably, interspecific mating resulted in the production of infertile eggs, while conspe- cific mating led to successful hatching. Interpretation & conclusion: The study reveals that Ae. aegypti and Ae. albopictus can asymmetrically interfere with each other’s reproduction, causing a ‘satyr’ effect. This understanding of interspecific competition and reproductive interference in these mosquito species could impact their coexistence in shared breeding habitats.
Diversity of mosquito natural enemies and their feeding efficacy on Aedes vectors
(Wolters Kluwer – Medknow, 2024-12) Dissanayake, Dinithi Shyamalee; Wijekoon, Chandana Dammika; Wegiriya, Hemantha
Background & objectives: Mosquito-borne diseases are a major health issue among communities in Asia, and dengue has become a serious public health concern in Sri Lanka with varying magnitude since 1960. With the realization of the failures and limitations of current vector control strategies, the authorities are moving towards simple, low- cost, and eco-friendly vector management methods. Thus, the present study was devised to evaluate the potential densities of mosquito natural enemies in natural water habitats in Galle district, Sri Lanka, and to investigate the feeding efficacy of prominent mosquito natural enemies on main dengue vectors (Aedes sp.) in a laboratory setting. Methods: The survey was carried out using eight sentinel sites in Galle district, and samples of mosquito natural enemies and mosquito larvae were collected, and identified using taxonomic keys. Results: Study records, the aquatic insects of family Hydrometridae, Belostomatidae, Notonectidae, Nepidae, Ranat- ridae, and Corixidae as dominant mosquito natural enemies, and Libellulidae and Dytiscidae insects as sub-dominant families. The highest density of the family Hydrometridae was recorded in rural, natural inland, and rocky study sites. The order Hemiptera was recorded as the key order of the mosquitos’ natural enemies in Galle district. The family Hydrometridae had the highest density of recorded mosquito natural enemies. Interpretation & conclusion: Aedes aegypti and Ae. albopictus were recorded as abundant vector mosquitoes. Family Nepidae is the most effective natural mosquito predator on Ae. aegypti and Ae. albopictus, and this knowledge will be vital for implementing future biological control strategies for Aedes vectors in Sri Lanka.
Characterization of Leclercia adecarboxylata isolated from field collected Anopheles subpictus in Berhampur, Odisha, India
(Wolters Kluwer – Medknow, 2024-12) Agrawal, Ankita; Barik, Tapan Kumar; Patel, Amiya Kumar
Background & objectives: Malaria, a vector-borne disease, is caused by Plasmodium species and transmitted by Anopheles species. Among these vectors, Anopheles subpictus has emerged as a potent malarial vector in coastal areas of India. Numerous studies have highlighted that bacterial communities within mosquito influence vector com- petence. The present study was designed to isolate and characterize bacterial microbiota from An. subpictus larvae. Methods: Isolation and purification of the predominant bacterial strain (AL1) was carried out. Morphological, bio- chemical, antibiotic susceptibility and molecular characterization of the isolated bacteria was performed. Results: Bacterial isolate (AL1) was found to be rod, gram negative, catalase positive and oxidase negative. AL1 was identified as Leclercia adecarboxylata (Accession number: OR649235) through 16S rRNA ribotyping. Further, the leaf extract of Nyctanthes arbortristis showed inhibitory effect against AL1. Interpretation & conclusion: The study provided the first report on the isolation of symbiotic bacteria (L. adecarbox- ylata) from An. subpictus and its control by leaf extract of Nyctanthes arbortristis. Isolated gram-negative bacterial strain might inhibit the development of mosquito vectors and can be implemented for various biological control strategies to combat malaria transmission.
Development of data-driven machine learning models and their potential role in predicting dengue outbreak
(Wolters Kluwer – Medknow, 2024-12) Mazhar, Bushra; Ali, Nazish Mazhar; Manzoor, Farkhanda; Khan, Muhammad Kamran; Nasir, Muhammad; Ramzan, Muhammad
Dengue fever is one of the most widespread vector-borne viral infections in the world, resulting in increased socio-economic burden. WHO has reported that 2.5 billion people are infected with dengue fever across the world, resulting in high mortalities in tropical and subtropical regions. The current article endeavors to present an overview of predicting dengue outbreaks through data-based machine-learning models. This artificial intelligence model uses real world data such as dengue surveillance, climatic variables, and epidemiological data and combines big data with machine learning algorithms to forecast dengue. Monitoring and predicting dengue incidences has been significantly enhanced through innovative approaches. This involves gathering data on various climatic factors, including temperature, rainfall, relative humidity, and wind speed, along with monthly records of dengue cases. The study functions as an efficient warning system, enabling the anticipation of dengue outbreaks. This early warning system not only alerts communities but also aids relevant authorities in implementing crucial preventive measures.
Investigation of in vitro and in vivo therapeutic activity of Tarantula cubensis extract (Theranekron®) on Leishmania major
(Wolters Kluwer – Medknow, 2024-12) Akyol, Elif; Polat, Zübeyda Ak?n
Background & objectives: Cutaneous leishmaniasis (CL) is a vector-borne parasitic disease caused by several species of the protozoan parasite Leishmania. The need for new anti-leishmanial drugs for the treatment of CL is complicated by factors such as high cost, toxicity, potential for resistance and limited long-term use of existing anti-leishmanial drugs. The aim of this study was to investigate the therapeutic effect of Tarantula cubensis alcoholic extract (TCE), which has been shown to have wound-healing, anti-inflammatory, regenerative, resolving and epithelialising effects, on Leishmania major promastigotes in vitro and in vivo in an experimental mouse model of CL. Methods: The effect of TCE on L. major promastigotes in vitro was investigated after determining non-cytotoxic concentrations of TCE using the XTT method. To establish a CL model, L. major amastigotes were injected into the paws of BALB/c mice. Lesion size and histopathological evaluation were used to assess the effect of treatment. Results: TCE was found to be effective against L. major promastigotes at 24 h and 48 h at concentrations 250 ?g/ mL, 125 ?g/mL and 62.5 ?g/mL (P<0.05). TCE was found to be more effective than meglumine antimonate in treating CL in the experimentally induced CL model in BALB/c mice. Interpretation & conclusion: The results suggest that TCE holds promising potential as a therapeutic agent for the treatment of CL. However, further extensive investigations are required to substantiate and expand our understand- ing in this area.
Identification of natural inhibitors targeting trehalase of Anopheles funestus in the management of malaria: A Biocomputational assessment
(Wolters Kluwer – Medknow, 2024-12) Al Ali, Amer; Asiri, Abdulaziz; Abu-Alghayth, Mohammed H; Althobiti, Maryam Musleh; Al Hader, Bandar Ali; Alhindi, Zain
Background & objectives: Anopheles funestus is playing an increasingly important role in malaria transmission in sub-Saharan Africa. Trehalase, an enzyme required for trehalose breakdown, is important for mosquito flight and stress adaptation. Hence, its inhibition has emerged as a promising malaria management strategy. Methods: A collection of 1900 natural compounds from the ZINC database were screened against the 3D modeled structure of An. funestus trehalase protein using in silico tools. ADMET-AI, a web-based platform, was used to predict the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of the selected compounds. Results: We report 5 natural compounds namely, ZINC00488388, ZINC00488525, ZINC00488566, ZINC00488304, and ZINC00488456 that demonstrated strong binding affinity to the trehalase protein. These compounds interacted with critical residues of the trehalase protein and exhibited good drug-like characteristics. Interpretation & conclusion: These compounds show promise as trehalase protein inhibitors for malaria manage- ment. Nonetheless, additional experimental studies are required to optimize these compounds as potential trehalase inhibitors.
The role of clinical and laboratory finding in the differential diagnosis of hantavirus and leptospirosis infections
(Wolters Kluwer – Medknow, 2024-12) ?ahin, Ahmet Melih; Çetin, Sinan; ?enel, ?lknur; Erdem-Çak?r, Tu?çegül; Ayd?n, Emsal; Yetkin, Meltem Arzu
Background & objectives: Hantavirus and leptospirosis infections are zoonotic diseases with similar clinical and laboratory findings. The aim of this study is to identify the distinguishing features of these two diseases, for which a definitive diagnosis can take a long time. Methods: Between September 2021 and June 2023, a total of 45 patients who were admitted to our hospital and were diagnosed with hemorrhagic fever with renal syndrome (HFRS) or leptospirosis were retrospectively evaluated. Patients were compared in terms of demographic data, clinical, and laboratory parameters. The role of these variables in predicting HFRS or leptospirosis was investigated. The two diseases were compared with regard to outcomes. Receiver operating characteristics were employed for the calculation of cut-off values, sensitivity, specificity, and positive and negative predictive values for parameters showing significant differences. A statistical significance level of p<0.05 was considered. Results: Fifteen patients diagnosed with HFRS and thirty patients diagnosed with leptospirosis were included in the study. In both groups, hospital admissions were observed with non-specific and similar symptoms. There was no statistically significant difference observed between the two groups in terms of length of hospital stay, blood product transfusion, requirement for hemodialysis, intensive care unit admission, the rate of return to normal renal function and mortality. Elevated ferritin levels were statistically significant in favor of HFRS, while lymphopenia, elevated bilirubin, CRP, and ESR were statistically significant in favor of leptospirosis. Interpretation & conclusion: The use of laboratory findings and clinical symptoms can aid in the challenging task of accurately diagnosing and using appropriate treatment for these two diseases.
Evaluation of InBios Scrub Typhus Detect IgM Rapid Test in acute fever cases from Southwest and East India
(Wolters Kluwer – Medknow, 2024-12) Punekar, Madhura; Jayaram, Anup; Varamballi, Prasad; Oliver, Dsa; Sabeena, Sasidharanpillai
Background & objectives: Scrub typhus is clinically undifferentiated from other aetiologies for acute febrile illness such as enteric fever, dengue, malaria, and leptospirosis. Rapid ELISA tests are being used as an alternative to im- munofluorescence assay in tropical countries. Methods: In this study, we compared and evaluated commercially available InBios Scrub Typhus Detect IgM Rapid Test (USA) for diagnosing human scrub typhus infection using archived and prospectively collected samples against the reference standard, InBios Scrub Typhus Detect IgM ELISA (USA). Results: The data analysis of archived samples on rapid test revealed a moderate sensitivity of 53.92% and a speci- ficity of 100%. Meanwhile, prospective serum samples demonstrated higher sensitivity and specificity of 96.4% and 94.6%, respectively. Interpretation & conclusion: The InBios Scrub Typhus Detect IgM rapid test can be a good point-of-care assay during surveillance, outbreak investigations, and case identification.
Spatiotemporal, demographic, and climatic drivers of malaria transmission in the endemic setting of Jazan, Saudi Arabia: A retrospective study
(Wolters Kluwer – Medknow, 2024-12) Alqassim, Ahmad Y
Background & objectives: Despite progress, malaria remains endemic in Jazan, Saudi Arabia necessitating epidemio- logical research to guide elimination strategies. This study analyzed recent surveillance data to elucidate drivers of sustained transmission. A retrospective epidemiological study was conducted using malaria surveillance data from the Jazan region of Saudi Arabia over a 3-year period from January 2018 to December 2020. Methods: Deidentified records of all confirmed malaria cases reported across Jazan during the study period were obtained from Jazan Department of Health infectious disease surveillance system. Additional meteorological data was acquired to assess climatic correlates. The final analysis included 5255 confirmed cases that met the complete- ness criteria for key variables. Descriptive statistics characterized cases across demographic factors and spatial and temporal distributions. Correlations and linear regression modeling identified associations between monthly cases and weather parameters mapping visualized geographic patterns. Results: Of the 5255 confirmed cases, most were concentrated in Baish sector (50.8–72.0% annually), affected adult male foreigners (93.8–97.0%), peaked inconsistently across seasons, and were imported (85.4–94.9%). Non-Saudi nationalities had 6-fold higher incidence versus Saudi citizens in 2020 (677.6 vs 23.1 per 100,000). Monthly cases associated negatively with temperature (p=0.015) and positively with windspeed (p=0.005). Interpretation & conclusion: Malaria persistence in Jazan involves geographic and demographic hotspots driven by imported infections and climate effects on vectors. Tailored programming aligned with evolving local dynamics will be essential to sustain elimination gains. Surveillance, optimized interventions, and flexible adaptation to high-risk locations and/or populations and meteorological influences are key priorities.
MBORS: Mosquito vector Biocontrol Ontology and Recommendation System
(Wolters Kluwer – Medknow, 2024-01) Jeyakodi, G; Shanthi Bala, P; Sruthi, OT; Swathi, K
Background & objectives: Mosquito vectors are disease-causing insects, responsible for various life-threatening vector-borne diseases such as dengue, Zika, malaria, chikungunya, and lymphatic filariasis. In practice, synthetic insecticides are used to control the mosquito vector, but, the continuous usage of synthetic insecticides is toxic to human health resulting in communicable diseases. Non-toxic biocontrol agents such as bacteria, fungus, plants, and mosquito densoviruses play a vital role in controlling mosquitoes. Community awareness of mosquito biocontrol agents is required to control vector-borne diseases. Mosquito vector-based ontology facilitates mosquito biocontrol by providing information such as species names, pathogen-associated diseases, and biological controlling agents. It helps to explore the associations among the mosquitoes and their biocontrol agents in the form of rules. The Mosquito vector-based Biocontrol Ontology Recommendation System (MBORS) provides the knowledge on mosquito-associated biocontrol agents to control the vector at the early stage of the mosquitoes such as eggs, larvae, pupae, and adults. This paper proposes MBORS for the prevention and effective control of vector-borne diseases. The Mosquito Vector Association ontology (MVAont) suggests the appropriate mosquito vector biocontrol agents (MosqVecRS) for related diseases. Methods: Natural Language Processing and Data mining are employed to develop the MBORS. While Tokenization, Part-of-speech Tagging (POS), Named Entity Recognition (NER), and rule-based text mining techniques are used to identify the mosquito ontology concepts, the data mining apriori algorithm is used to predict the associations among them. Results: The outcome of the MBORS results in MVAont as Web Ontology Language (OWL) representation and MosqVecRS as an Android application. The developed ontology and recommendation system are freely available on the web portal. Interpretation & conclusion: The MVAont predicts harmless biocontrol agents which help to diminish the rate of vector-borne diseases. On the other hand, the MosqVecRS system raises awareness of vectors and vector-borne diseases by recommending suitable biocontrol agents to the vector control community and researchers.
A case series of Mediterranean spotted fever and murine typhus with neurological manifestations
(Wolters Kluwer – Medknow, 2024-07) Hammami, Fatma; Koubaa, Makram; Chakroun, Amal; Rekik, Khaoula; Mezghani, Sonda; Hammami, Adnane; Marrakchi, Chakib; Smaoui, Fatma; Jemaa, Mounir Ben
Background & objectives: Severe cases with neurological manifestations of rickettsiosis have been reported. We aimed to identify the epidemiological, clinical and laboratory features of central nervous system rickettsial infec- tions and to describe the treatment. Methods: We carried out a retrospective study that included all patients hospitalized with rickettsiosis in the infec- tious diseases department of Hedi Chaker University Hospital in Sfax, Tunisia between 1993 and 2018. Results: We identified 47 patients with central nervous system rickettsial infections among 440 patients with rickettsial infections (10.7%). Skin rash (31.9% vs 87.8%; p<0.001) and eschar (4.2% vs 27.7%; p<0.001) were less frequent among patients with central nervous system rickettsial infections. Complications (6.4% vs 0.5%; p=0.01) and death (4.2% vs 0.3%; p=0.03) were more frequent among patients with central nervous system rickettsial infections. Interpretation & conclusion: Cardinal clinical features and typical laboratory results including thrombocytopenia were less frequent, and prognosis was more severe in patients with central nervous system rickettsial infections.
Seroprevalence study of dengue-malaria coinfection in an East-Cameroonian public hospital: A comparison between malarial and non-malarial groups
(Wolters Kluwer – Medknow, 2024-01) Ndeme, Elodie Ayangma; Tietcheu, Borris Rosnay Galani; Demanou, Sylvie Agokeng; Djamen, Dieudonne Pascal Chuisseu; Yanou, Nicolas Njintang
Backgrounds & objectives: Recent research in Cameroon reported several occurrences of dengue in urban settings, but concurrent dengue-malaria infection has received less attention, particularly in the East region. Methods: A two-month cross-sectional and comparative research was performed at Bertoua Regional Hospital which included 50 malaria-positive participants and 90 non-malaria subjects. Participants were selected and provided with a questionnaire to collect sociodemographic data. Blood samples were collected and tested for dengue infection and hematological parameters were assessed. Results: Dengue fever was found in 14% of malarial patients vs 66.66% of controls. Secondary dengue infection was more prevalent in malarial patients than in non-malarial patients. Gender, age, and place of residence were positively correlated to dengue seropositivity. Platelets were substantially lower (P<0.001) in the malarial group than in the non-malarial group. Interpretation & conclusion: In the study, coinfected patients were found to be more vulnerable to dengue, emphasizing the importance of epidemiological surveillance.
Isolation and molecular detection of dengue and chikungunya virus from field-collected adult mosquitoes in Kelantan, Malaysia
(Wolters Kluwer – Medknow, 2024-01) Jusoh, Tuan Nur A Mat; Jaafar, Izhan S; Shueb, Rafidah H
Background & objectives: Dengue and chikungunya infections are one of the major health problems that have plagued the human population globally. All dengue virus (DENV) serotypes circulate within Malaysia with particular serotypes dominating in different years/outbreaks. In the state of Kelantan, an increasing number of DENV and chikungunya virus (CHIKV) new cases have been reported, including several deaths. This study aimed to isolate and detect these arboviruses from adult mosquitoes in Kelantan. Methods: Adult mosquito samples were collected from January to August 2019 and were identified according to gender, species and locality. The isolation of the virus was done in C6/36 cells. Dengue NS1 antigen was carried out using direct mosquito lysate and mosquito culture supernatant. Detection and serotyping of the DENV was performed using multiplex RT-PCR and CHIKV detection using a one-step RT-PCR assay. Results: Of 91 mosquito pools, four were positive for NS1 antigen comprising two pools (2.2%) of male Ae. albopictus (Pulau Melaka and Kubang Siput) and two pools (2.2%) of Ae. aegypti (Kampung Demit Sungai). DENV 1 was detected in one pool (0.9%) of female Ae. albopictus among 114 tested Aedes pools. Two pools of 114 pools (1.7%) from both male Aedes species were positive with double serotypes, DENV 1 and DENV 2 (Pulau Melaka). However, no pool was positive for CHIKV. Interpretation & conclusion: The presence of DENV and the main vectors of arboviruses in Kelantan are pertinent indicators of the need to improve vector controls to reduce arbovirus infections among people in the localities.

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