Impact of urbanization on the abundance and distribution of Anophelines population in Ghaziabad district, Uttar Pradesh, India.

BACKGROUND OBJECTIVES: In urban areas, upsurge in population has resulted in more breeding sites for malaria vectors, and hence this scenario potentially undermine malaria elimination and control programs. The change in land use due to urbanization may result in the presence and distribution of malaria vectors. Understanding potential malaria vectors is essential for current and future malaria transmission control strategies. This study investigated the effects of rapid urbanization on malaria vectors An. culicifacies s.l. and An. stephensi L. in Ghaziabad district. METHODS: Ghaziabad district which presents several levels of urbanization was selected for this study. Entomological investigations were conducted seasonally from 2014-2016 in the rural, urban, and peri-urban regions. Vector incrimination study was done using ELISA (confirmation by PCR) on suspected Anopheles vectors viz. An. culicifacies, An. stephensi, An. annularis and An. subpictus. RESULTS: An. culicifacies showed alteration in distribution influenced by rural and agricultural land whereas An. stephensi was found to be influenced by artificial habitats and population growth. INTERPRETATION CONCLUSION: The study also confirms the association between the abundance of malaria vectors and land use change.

Influence of climatic factors on the life stages of Aedes mosquitoes and vectorial transmission: A review.

BACKGROUND OBJECTIVES: Aedes aegypti and Aedes 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 Aedes aegypti and Aedes 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 setting, assessing both conspecific and interspecific 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 exhibited high insemination rates, with percentages of 98% and 94%, respectively. However, interspecific mating exhibited interesting asymmetries: Ae. albopictus males achieved a notable insemination success rate of 28% when mating with Ae. aegypti females, while Ae. aegypti males achieved only 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 conspecific 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.

Profiles of global mutations in the human intercellular adhesion molecule-1 (ICAM-1) shed light on population-specific malaria susceptibility.

Plasmodium falciparum is responsible for malaria-related morbidity and mortality. PfEMP1 (P. falciparum erythrocyte membrane protein 1) mediates infected erythrocytes adhesion to various surface vascular receptors, including intercellular adhesion molecule-1 (ICAM-1), associating this interaction with severe malaria in several studies. Genetic variation in host ICAM-1 plays a significant role in determining susceptibility to malaria infection via clinical phenotypes such as the ICAM-1Kilifi variant which has been reported to be associated with susceptibility in populations. Our genomic and structural analysis of single nucleotide polymorphisms (SNPs) in ICAM-1 revealed 9 unique mutations each in its distinct A-type and BC-type PfEMP1 DBLß-interacting regions. These mutations are noted in only a few field isolates and mainly in the African/African American population. The ICAM-1Kilifi variant lies in a flexible loop proximal to the DBLß-interacting region. This analysis will assist in establishing functional correlations of reported global mutations via experimental and clinical studies and in the tailored design of population-specific genetic surveillance studies. Understanding host polymorphism as an evolutionary force in diverse populations can help to predict predisposition to disease severity and will contribute towards laying the framework for designing population-specific personalized medicines for severe malaria.

Chemical constituents and strong larvicidal activity of Solanum xanthocarpum among selected plants extracts against the malaria, filaria, and dengue vectors.

BACKGROUND & OBJECTIVES: The role of mosquitoes is instrumental in the transmission of various diseases. Mosquitoe-borne diseases account for a significant share of the global burden of total infectious diseases. Vector control is the principal method for the control of these mosquito-borne diseases. Plant-derived insecticides serve as an effective alternative to chemical insecticides. The present study has been undertaken to assess the larvicidal potential of methanol and petroleum ether extracts of leaves of Solanum xanthocarpum, Parthenium hysterophorus, Manihot esculenta, and Chamaecyparis obtusa. METHODS: Larvicidal activity was tested against the early four-stage instar larvae of laboratory-reared susceptible strains of the malaria vector, Anopheles stephensi, dengue fever vector, Aedes aegypti, and the lymphatic filariasis vector, Culex quinquefasciatus at 20 to 120 ppm concentrations. Further, liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectroscopy (GC-MS) analyses were carried out to identify the bioactive compounds present in the methanolic leaf extracts of Solanum xanthocarpum for designing a larvicidal product in future. RESULTS: After 72 h of exposure high larvicidal activities were observed in methanolic and petroleum ether leaves extract of S. xanthocarpum against An. stephensi, Ae. aegypti and Cx. quinquefasciatus. The larvicidal activities for methanol and petroleum ether leaf extract of S. xanthocarpum with LC50 = 09.201 and 12.435 ppm and LC90 = 21.578 and 27.418 ppm for An. stephensi; LC50 = 11.450 and 10.026 ppm and LC90 = 26.328 and 22.632 ppm for Ae. aegypti and LC50 = 12.962 and 13.325 ppm and LC90 = 26.731 and 30.409 ppm for Cx. quinquefasciatus, respectively, were found to be most effective. GC-MS analysis revealed 43 compounds, amongst these phytol (13.09%), 3-allyl-2-methoxy phenol (9.55%), (9Z, 12Z)-9, 12-octadecadienoyl chloride (7.93%), linoleic acid (5.45%), alpha-tocospiro B (5.08%) and hexadecanoic acid (4.35%) were identified as major compounds. INTERPRETATION & CONCLUSION: Present work showed that leaf extracts of S. xanthocarpum are a source of potential natural candidate that possess several phytochemicals which can be explored further for the development of ecologically safer mosquito control products.

Studies on the breeding potential and entomological indices of dengue vector Aedes aegypti and Aedes albopictus in the district Ghaziabad of Uttar Pradesh, India.

BACKGROUND & OBJECTIVES: The female Aedes mosquito is a vector of many arboviruses-borne diseases. The evidence and information regarding their breeding habitats are vital for implementing appropriate control policies. METHODS: An entomological survey was done at three sites in Ghaziabad district of Uttar Pradesh, India viz. Indirapuram, Vasundhara, and Vaishali to generate the first boundary line information of breeding sites of Aedes aegypti larvae for the early prevention and control interventions for dengue management. RESULTS: A total of 2994 containers were checked in 1169 households at the time of the survey for breeding sites of Aedes mosquito during the pre-monsoon, monsoon, and post-monsoon period, out of which 667 containers were found positive in 518 positive households. The total HI, CI, and BI were 44.31, 22.27, and 57.05 respectively. The maximum and minimum breeding indices were found during monsoon and pre-monsoon respectively. The most preferred containers for Aedes breeding were cement tanks for lotus plants in nurseries, drums, and small and large size pots for storage of water and ornamental plants mostly in 8 plant nurseries. INTERPRETATION & CONCLUSION: Breeding of Aedes was found in nurseries and desert coolers which were the primary breeding containers found during the survey. The containers found positive during surveys were emptied or destroyed with the help of the local community and the breeding status of nurseries was informed to the health authorities of Ghaziabad to take necessary action against the breeding sites of the Aedes mosquitoes.

A rapid method for DNA Isolation from blood, dried blood spots and rapid diagnosis test.

Background & objectives: Malaria is a parasitic disease spread by Plasmodium parasite. Microscopy, lateral flow devices such as the Rapid Diagnostic Test (RDT), molecular methods such as Polymerase Chain Reaction (PCR), isothermal methods such as Loop-mediated isothermal amplification (LAMP), and other diagnostic methods are available for malaria. On the other hand, the accuracy of molecular diagnosis is dependent on genomic DNA isolation. A quick method for isolating and subjectively determining the presence of genomic DNA from blood, dried blood spot (DBS), and rapid diagnostic test (RDT), was identified. Methods: We have developed a protocol for isolating DNA from blood, DBS, and RDTs using the HUDSON Buffer (TCEP and EDTA). Isolated genomic DNA was seen with SYBR Safe DNA stain (1X) under a UV transilluminator without running in 0.8 percent gel electrophoresis or using a spectrophotometer. Results: The technique for DNA isolation was accurate for the presence of malaria parasite genomic DNA from positive samples confirmed by microscopy with a sensitivity of 76% and specificity of 78.67% and RDT with a sensitivity of 88% and specificity of 66%. The requirements were minimal, and the process took 30 minutes for a hundred sample processing. Interpretation & conclusion: Finding a fast and reliable method of separating nucleic acids from many samples is crucial. This approach extracts intact genomic DNA in under ten minutes, making it ideal for large-scale investigations.

Susceptibility status of Aedes aegypti (Diptera: Culicidae) against insecticides of public health use in Delhi and NCR region, India.

BACKGROUND & OBJECTIVES: Aedes (Stegomyia) aegypti is a primary vector responsible for the transmission of various arboviral diseases in India. Without an effective drug or vaccine against these diseases, chemical insecticide-based vector control supplemented with source reduction remains the best option for their effective management. The development of insecticide resistance due to the continuous use of insecticides might affect the control operations. METHODS: Adults and larvae of Aedes aegypti were collected from different localities in Delhi. Larvae were exposed to discriminating (0.02mg/l) and application (1mg/l) doses of temephos. WHO tube assay was conducted for F1 adults using impregnated insecticide papers of dichlorodiphenyltrichloroethane (DDT), malathion, deltamethrin, permethrin, cyfluthrin, and lambda-cyhalothrin. RESULTS: Larvae of Ae. aegypti were found resistant (76.0%) to the discriminating dose of temephos, whereas suscep-tible (100.0%) to the application dose of the temephos. Adult Aedes (Fl) mosquitoes were resistant to DDT (23.7%), malathion (90.5%), deltamethrin (76.0%), permethrin (96.2 %) cyfluthrin (85.5%), and lambda-cyhalothrin (94.0%). INTERPRETATION & CONCLUSION: Indoor residual spray is not used in Delhi for vector control. Resistance in Aedes might be due to pesticide usage for agricultural activities in peripheral regions of Delhi. There is a need to investigate more on the insecticide resistance mechanisms for indirect resistance development. Understanding the insecticide susceptibility status of urban vectors is critical for planning effective control strategies.

Design and validation of multiplex polymerase chain reaction as a diagnostic tool for Plasmodium species.

BACKGROUND & OBJECTIVES: The highly sensitive method for a true understanding of malaria prevalence is of utmost importance for India's elimination strategy. The PCR reaction type with rapid detection, cost-effectiveness, and less workforce should be preferable. Multiplex PCR type accomplishes the present requirement by saving time and resources to find true surveillance data for malaria, especially in low-parasitemia/asymptomatic groups or populations. METHODS: The present study focuses on designing multiplex PCR (mPCR) to detect simultaneously Plasmodium genus (PAN) and two common Plasmodium species found in India. It is compared to standard nested PCR on 195 clinical samples to diagnose malaria. The mPCR was designed with a minimum number of primers, leading to less clogging and effective and enhanced detection. It contains one common reverse primer and three forward primers amplifying three targeted genes corresponding to P. falciparum, P. vivax, and Plasmodium genus. RESULTS: The sensitivity and specificity for mPCR were 94.06 and 95.74, respectively. The limit of detection for mPCR was 0.1 parasites/µl. The study has shown a ROC curve area for the mPCR of 0.949 for Plasmodium genus and P. falciparum and 0.897 for P. vivax with standard nPCR. INTERPRETATION & CONCLUSION: The mPCR is rapid in detecting species together, cost-effective, and requires fewer human resources than the standard nPCR. Therefore, the mPCR can be used as an alternative technique for the higher sensitive detection of the malaria parasite. It could also become a vital tool for determining malaria prevalence, facilitating the application of the most effective measures.

Mosquito larvicidal potential of Solanum xanthocarpum leaf extract derived silver nanoparticles and its bio-toxicity on non-target aquatic organism.

BACKGROUND & OBJECTIVES: Mosquitoes are insects of public health importance that act as a vector to transmit various vector-borne diseases in humans including dengue, malaria, filariasis and yellow fever. The continually employed synthetic insecticides have developed resistance in mosquitoes. Nano-based botanical insecticides can be considered as the best alternative due to several advantages like being simple, non-pathogenic, biodegradable and safe to the environment. The present work reported the maximum larvicidal potential of green synthesized silver nanoparticles (AgNPs) derived from the leaf extract of Solanum xanthoearpum against the third instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus over its crude leaf extract. METHODS: The synthesis of AgNPs was done by adding leaf extract into silver nitrate solution in a conical flask. The characterization of AgNPs was done using different techniques such as UV-Vis, SEM, TEM, XRD, DLS and SAED. FT-IR analysis was done to find out the compound responsible for bio-reduction of silver nitrate. Larvicidal activity of AgNPs was checked against An. stephensi, Ae. aegypti, and Cx. quinquefasciatus according to WHO standard protocol and toxicity was evaluated against Poecilia reticulate. RESULTS: A change in colour was observed indicating the synthesis of AgNPs which was further confirmed by a strong surface plasmon resonance peak at 421nm under the UV-Vis spectrum. SEM and TEM micrographs exhibited that the most common shape of AgNPs was spherical. XRD spectrum showed crystalline nature of silver nanoparticles. FT-IR spectrum showed the presence of various functional groups such as carboxyl and hydroxyl which might be responsible for bio-reduction and capping of silver nanoparticles. Further, silver nanoparticles were very effective against An. stephensi, Ae. aegypti, and Cx. quinquefasciatus with LC50 and LC90 values of 1.90, 2.36, 2.93, 3.82, 4.31 and 7.63 ppm, respectively, as compared to aqueous leaf extract after 72 h of exposure and were non-toxic against non-target organism P. retieulata. Interpretation & eonelusion: From the above finding, it can be concluded that fabricated AgNPs can be promising eco-friendly tools for controlling mosquito vectors.

Sustainable control of malaria employing Gambusia fishes as biological control in Jalore and Barmer districts of Western Rajasthan.

Sardar Sarovar Irrigation Canal system was constructed by Narmada Valley Development Authority (NVDA) to cater to drinking water as well as for irrigation purposes in Jalore and Barmer districts of Western Rajasthan. To cater to the needs of water for the villagers in the command areas, 'Diggies' (surface water tanks) with 'Sumpwells' (water supply surface tanks) were installed. In a health impact assessment study of the irrigation canals from December 2010 to February 2016, the breeding of two major malaria vectors. An. culicifacies and An. stephensi were observed in diggies and sumpwells. As a biological control, Gambusia affanis fishes were employed for larval control in such stagnated water sites during the intervention phase viz. February 2012 in 251 diggies and 251 sumpwells. A significant reduction of breeding in diggies (99.54%) and sumpwells (97.81%) was observed. The positivity and larval density (dip index) were monitored in the control from up to February 2016 for their sustainability.

Comparative Assessment of Diagnostic Performance of Cytochrome Oxidase Multiplex PCR and 18S rRNA Nested PCR.

Malaria elimination and control require prompt and accurate diagnosis for treatment plan. Since microscopy and rapid diagnostic test (RDT) are not sensitive particularly for diagnosing low parasitemia, highly sensitive diagnostic tools are required for accurate treatment. Molecular diagnosis of malaria is commonly carried out by nested polymerase chain reaction (PCR) targeting 18S rRNA gene, while this technique involves long turnaround time and multiple steps leading to false positive results. To overcome these drawbacks, we compared highly sensitive cytochrome oxidase gene-based single-step multiplex reaction with 18S rRNA nested PCR. Cytochrome oxidase (cox) genes of P. falciparum (cox-III) and P. vivax (cox-I) were compared with 18S rRNA gene nested PCR and microscopy. Cox gene multiplex PCR was found to be highly specific and sensitive, enhancing the detection limit of mixed infections. Cox gene multiplex PCR showed a sensitivity of 100% and a specificity of 97%. This approach can be used as an alternative diagnostic method as it offers higher diagnostic performance and is amenable to high throughput scaling up for a larger sample size at low cost.

The impact of mosquito proof lids of underground tanks "tanka" on the breeding of Anopheles stephensi in a village in western Rajasthan, India.

BACKGROUND: Western Rajasthan in India has a typical desert climate. Until the introduction of the canal water irrigation system, malaria was an unstable and seasonal occurrence. Due to the scarcity of water, the community practised having one large underground tank (locally known as the tanka) in their house to collect rainwater for long-term household use. Anopheles stephensi, one of the major malaria vectors, breeds in improperly covered "tankas" if not properly covered and harbours a vector population throughout the year. METHODS: Two villages, Ajasar (intervention) and Tota (control), with similar ecological features, were selected for the study. A pre-intervention survey was carried out in both villages to assess the presence and quality of lids of tankas, and mosquito breeding and adult mosquito density. Awareness of the community about malaria and mosquitoes was also assessed during the pre-intervention period. In the intervention village, damaged or improper lids were replaced with improved mosquito proof polyvinyl chloride plastic (PVC) lids and lasted longer than the conventional lids. The fitness of the lids was assessed one year after the pre-intervention survey. The entomological assessment was carried out in both intervention and non-intervention villages. The level of community awareness about malaria, mosquitoes, their breeding places, and the role of tankas in malaria transmission was assessed both during pre- and post-intervention. RESULTS: During the pre-intervention survey, Anopheles breeding was found in 22.1% (58/262) of tankas in the intervention village and 27.1% (19/70) in tankas in the control village. Mosquito breeding was observed in the tankas with iron lids in the intervention village (48.3%) and the control village (42.1%). In the intervention village, out of 262 tankas in the village, 200 lids were replaced, resulting in the complete absence of mosquito breeding. In the pre-intervention survey conducted in May 2018, Anopheles stephensi consisted of 46% of adult mosquitoes in the intervention village and 55% in the control village. Its density was significantly reduced to 0.55 per man-hour (94.95%) and 0.22 per man-hour (97.8%) in the post-intervention survey in June 2018 and a follow-up survey in May 2019, respectively, in the intervention village. DISCUSSION: The density of Anopheles stephensi adults was reduced significantly (97.8%) in the intervention village due to complete prevention of breeding in the underground tankas in the intervention village as compared to the control with no density reduction. The awareness level of the community was also improved due to their involvement in the study. CONCLUSION: Provision of proper metal lids or replacement of damaged lids on underground water storage tanks as an environmental management approach prevented the breeding of  the malaria vector, Anopheles stephensi, in a desert village in western Rajasthan.

Mobile app based pictorial identification key for Indian anophelines.

BACKGROUND & OBJECTIVES: Malaria control strategies for a particular area largely depends on the correct identification of the mosquito species prevalent in that area. This study aimed to develop an android mobile app named 'Pictorial Indian anophelines key', which can be used to identify the 58 species of Indian female adult anophelines based on morphological characteristics. METHODS: The pre-requisite to use this app requires a minimum basic knowledge of mosquito morphological characteristics and features. The user needs to view the collected mosquito under a dissecting binocular microscope and has to select the observations on the app presented in the form of labelled picture format. The app uses a divide and conquer algorithm which narrows the selection from genus level to final identification of species. RESULTS: The app is user-friendly, quick and it accurately identifies the mosquito species in a maximum of six consecutive clicks. The result displays a complete image of identified mosquito along with its quick identification features. It can be used for both subgenus Cellia and Anopheles. INTERPRETATION & CONCLUSION: This pictorial key-based mobile app could be helpful for entomologists, malariologists, researchers, public health workers as well as students in the quick and correct identification of anopheline mosquitoes prevalent in India which in turn could be helpful in devising appropriate approaches towards malaria control and prevention. The app can be modified as per future requirements.

Co-distribution of dengue and Chikungunya viruses in Aedes mosquitoes of Delhi, India.

BACKGROUND & OBJECTIVES: In India, vector-borne diseases, dengue and chikungunya are major public health concerns. In recent decades, dengue outbreaks have been reported in almost every part of India. In 2016, India recorded 101388 dengue cases and 210 deaths, including 4337 cases and six deaths in Delhi, whereas Chikungunya outbreaks were reported from several states in 2006, with 1.3 million cases. The Dengue virus (DENV) and Chikungunya virus (CHIKV) are both transmitted by the same Aedes mosquito species. DENV and CHIKV co-infections have been reported in 13 of 98 countries, with both viruses being transmitted locally. The reasons for the sudden upsurge in cases of these diseases are undetermined. METHODS: From March to December 2016, a study was carried out in 66 localities of Delhi in collaboration with the Municipal Corporation of Delhi. Localities were selected on the basis of confirmed dengue cases reported during the last five years and the study area was visited once a month. A door-to-door entomological survey was conducted to identify Aedes breeding in all water-filled containers in and around houses. Both immature and mature stages of Aedes mosquitoes were collected. Mosquitoes were pooled (n≤10 each for male and female) breeding site-wise and stored in Trizol at -80°C. The Chikungunya and dengue viruses were detected using a multiplex RT-PCR. RESULTS: A total of 981 Aedes mosquitos were distributed among 146 Pools, and DENV and CHIKV were detected using Multiplex Reverse Transcriptase-PCR. Chikungunya virus was identified in 19 pools of females captured adults, whereas dengue virus was found in 8 pools of females captured adults. There was no evidence of coinfection in any of the pools. INTERPRETATION & CONCLUSION: In endemic areas, continuous surveillance for both dengue and Chikungunya viruses is required to identify and characterize these viral pathogens. This information will also help implement effective strategies to combat outbreaks produced by these emerging viral pathogens.

Role of Various Gene Expressions in Etiopathogenesis of Type 2 Diabetes Mellitus.

CONTEXT: Diabetes is a metabolic disease, with high mortality, and is characterized by increased glucose levels in the blood occurring due to poor pancreatic insulin secretion or development of insulin resistance in the body. Type 2 DM (T2DM) represents 90% of diabetic cases, and its pathogenesis involves a genetic correlation with insulin resistance, ß-cell dysfunction, lifestyle, and environmental factors. OBJECTIVE: The current study intended to examine the pathophysiology of T2DM, including factors influencing insulin resistance and beta (ß)-cell dysfunction as well as the genetic factors that indicate susceptibility to T2DM. DESIGN: The research team performed a narrative review by searching the Mendeley, Science Direct, Medline, PubMed, Google Scholar, and Springer databases. The search used the keywords Diabetes, insulin secretion and environmental factor. SETTING: This study was take place in School of Pharmacy, Suresh Gyan Vihar University, Jaipur, India. RESULTS: The paraoxonase-1 gene Q192R and the L55M, INS-VNTR, and IL-38 gene alterations can result in insulin resistance while PAM variants and miR-132 and miR-18 expression can lead to ß-cell dysfunction. Palmitate-like FFA expression of mRNA MafA, and IRS-2 can lead to impairment of insulin secretion. CONCLUSIONS: T2DM is the most common metabolic disorder of the twenty-first century, and its incidence, complications, and morbidity increase every day. The examination of T2DM's pathophysiology and the literature review have revealed that it has a strong correlation with genetic defects.

The Impact of COVID-19 Pandemic Infection in Patients Admitted to the Hospital for Reasons Other Than COVID-19 Infection.

COVID-19 or SARS CoV-2 is a worldwide public health emergency. The first case of COVID-19 was described in Wuhan, China in December, 2019 and within a short time the infection had spread quickly to the rest of China and then the world. The COVID-19 pandemic has had a huge impact on patients who do not have COVID-19 but other diseases like cancer, diabetes, and many more non-communicable diseases; their care is compromised because of the pandemic. COVID-19 also poses a work-related health risk for healthcare workers who are treating patients with COVID-19, and many have themselves become infected. Healthcare workers involved in diagnosing and treating patients with COVID-19 should be evaluated for stress, anxiety and depression.

Larvicidal activity of Ricinus communis extract against mosquitoes.

BACKGROUND & OBJECTIVES: Vector control strategies play significant role in reducing the transmission of malaria, dengue and other vector-borne diseases. The control of vector population using synthetic insecticides has resulted in development of insecticide resistance and negative effects on humans and environment. The present investigation evaluated the larvicidal potential of methanol, dichloromethane and hexane extracts of leaves and seeds of Ricinus communis (castor) plant against the early IV instar larvae of the dengue vector, Aedes aegypti, and malaria vector, Anopheles culicifacies. METHODS: Plant extracts were screened for their efficacy against Ae. aegypti and An. culicifacies using WHO standard larval susceptibility test method. Dose response bioassay was performed to get lethal concentrations. Further, gas chromatography-mass spectroscopy (GC-MS) analysis was carried out to identify the bioactive chemical constituents of the extracts of R. communis. Toxicity of the extracts towards non-target organism, Poecilia reticulata was also evaluated. RESULTS: The leaf and seed extracts of R. communis showed significant mortality against the larvae of Ae. aegypti and An. culicifacies at concentrations of 31.25, 62.5, 125, 250, 500 ppm; and 2, 4, 8, 16, 32, 64 ppm, respectively. At 24 h of the exposure period, the larvicidal activities were highest for the methanol extract of seeds with LC50 15.52 and 9.37 ppm and LC90 45.24 and 31.1 ppm for Ae. aegypti and An. culicifacies, respectively. The methanol extract of seeds and leaves was found to be safe towards non-target organism, P. reticulata. The GC-MS profile showed that seed extracts were having higher concentration of stigmasterol (7.5%), ß-sitosterol (11.48%), methyl linoleate (2.5%), vitamin E (11.93%), and ricinoleic acid (34%) than the leaf extracts. INTERPRETATION & CONCLUSION: The seed extract of R. communis has better larvicidal activity than the leaf extract and can be used as an effective larvicide against mosquitoes. The non-toxicity of the extracts towards P. reticulata further suggests that these plant extracts could be used along with predatory fishes in integrated vector control approaches.

Detection of dengue virus in individual Aedes aegypti mosquitoes in Delhi, India.

BACKGROUND & OBJECTIVES: Delhi, the capital city of India, has so far witnessed several outbreaks of dengue fever since 1967 (last one reported in 2013). Improved virological and entomological surveillance are the only tools that can help in prevention of dengue as well as in the development of dengue control programmes. The aim of the study was to conduct a prospective field study to detect dengue virus in adult Aedes aegypti mosquitoes collected from various localities represented by different socioeconomic groups in Delhi. METHODS: The study areas were selected and categorized into high, medium and low income groups on the basis of socioeconomical characteristics of the resident population, where dengue cases were reported during the past three years by MCD. Dengue viral infection was detected in the head squash of each adult mosquito by immunofluorescent assay (IFA) employing monoclonal antibodies against dengue virus (DENV). A total of 2408 females and 1206 males of Ae. aegypti were collected and tested by IFA. RESULTS: Out of 2408 Ae. aegypti females, 14 were found positive, with minimum infection rate (MIR) of 5.8 per 1000 mosquitoes. Among the 18 study areas, 11 localities were found positive for dengue virus infection. Low income group (LIG) areas showed highest mosquito infectivity (9.8), followed by medium income group (MIG), i.e. 6.2; while least was observed in high income group (HIG), i.e. 1.3. No vertical transmission of dengue virus could be detected in 1206 Ae. aegypti males collected. INTERPRETATION & CONCLUSION: The study concludes that there was high MIR in the identified localities of low and medium income groups. Estimation of MIR in a female Aedes mosquito in the existing arsenals for dengue surveillance would be an added advantage for early warning of dengue outbreak. The presence of infected mosquitoes in identified localities of Delhi was alarming and require rigorous vector surveillance so that the severe outbreaks can be prevented.

Use of different coloured ovitraps in the surveillance of Aedes mosquitoes in an arid-urban area of western Rajasthan, India.

BACKGROUND & OBJECTIVES: In the absence of any commercially available dengue vaccine or antiviral therapy, controlling the primary mosquito vector, Aedes aegypti, is currently the only means to prevent dengue outbreaks. Ovitraps are being employed as a sensitive method for detecting the presence of Ae. aegypti. Size, colour, material, paddle and use of oviposition attractant have been reported as important factors influencing the efficacy of ovitraps. METHODS: For the study of coloured ovitraps baited with grass infusion, 24 households were randomly selected in a locality and five ovitraps/premises were installed. Weekly ovitrap surveys were conducted during the study for four times. Ovitrap data were analyzed on the basis of its location, day-wise percent positivity, presence of eggs laid and inference of different ovitrap parameters were drawn. RESULTS: Grass infusion, used in the ovitraps has highest attractiveness on Day 6 in comparison to other days. Percent positivity of different coloured ovitraps revealed that red coloured ovitraps have highest positivity (92.7%), followed by black and orange (91.7% each), green (76.3%) and transparent (45.8%). The individual colour-wise ovitrap positivity revealed that the highest ovitrap positivity on Day 1 was recorded for black colour (21.8%), which on D2 and D3, in case of red colour (37.5 and 26%). However, on D4, D5 and D6 highest number of positive ovitraps was recorded in orange coloured (12.5, 21.9 and 31.3%, respectively) and on D7 highest number of positive ovitraps were recorded in transparent (21.9%), followed by green coloured ovitrap (20.8%). The overall location-wise ovitraps positivity revealed that highest positivity was recorded among the ovitraps installed inside bathrooms (92.0%), followed by bedrooms (85.0%), lobby (66.7%) and stores (48.3%). INTERPRETATION & CONCLUSION: The study revealed that for immediate detection of the presence of gravid females in a particular locality during epidemics, the black coloured ovitraps may be useful, however, in normal situations for surveillance of the vector species, the orange coloured ovitraps might be more suitable. Bathrooms were found to be the highest positive location for pitching ovitraps.

Emerging roles of SnoRNAs in the pathogenesis and treatment of autoimmune disorders.

SnoRNAs (small non-coding RNAs) have recently gained prominence in autoimmune diseases, revealing their crucial role in modulating the immune response and contributing to disease pathogenesis. Initially known for their involvement in ribosomal RNA processing and modification, molecular biology and genomics advancements have uncovered their broader impact on cellular function, especially in autoimmune disorders. Autoimmune diseases represent conditions characterized by the immune system's erroneous attacks on self-tissues, encompassing disorders like systemic lupus erythematosus, rheumatoid arthritis, and multiple sclerosis. The complex etiology of these conditions involves a delicate interplay of genetic and environmental factors. Emerging evidence suggests that snoRNAs initially recognized for their housekeeping roles, extend their influence on immune regulation through diverse mechanisms. SnoRNAs have been implicated in epigenetic modification, directly affecting the gene expression profiles of immune cells. Their ability to guide site-specific changes on ribosomal RNAs and other non-coding RNAs can significantly influence the translation of proteins involved in immune response pathways. Moreover, snoRNAs interact with key immune-related proteins, modulating their functions and subsequently impacting immune cell development, activation, and tolerance. Dysregulation of snoRNA expression has been observed in various autoimmune diseases, underscoring their potential as biomarkers for disease diagnosis, prognosis, and therapeutic targets. Manipulating snoRNA expression or activity is a promising therapeutic intervention avenue, offering the potential for personalized treatment strategies in autoimmune diseases. However, there remains a need for comprehensive research efforts to elucidate the precise molecular mechanisms underlying snoRNA-mediated immune modulation. Further investigations in this domain are essential to unravel the potential of snoRNAs in autoimmune disorders.