A study on the role of aedes mosquitoes in arboviruses and SARS-CoV-2 infection: A new challenge.

Chikungunya, Zika, Dengue Viruses, and now Novel Coronavirus are global health challenges that cause human diseases ranging from febrile illnesses to death. Most of these viruses are mainly vectored by Aedes mosquitoes worldwide. Molecular detection of arboviruses was made in female Aedes mosquito pools caught from all the seven districts by using a reliable molecular technique, "RT-PCR." From 216 collections of Aedes species, arboviruses were detected in 27, including only Alphavirus genus to determine mosquito abundance and evaluate the potential role of Aedes aegypti and Ae. albopictus mosquitoes in arboviruses and nvel Coronavirus transmission. 5322 mosquitoes were collected using aspirators; 35.31% (n = 2049) were identified as female Aedes using morphological keys, pooled into 216 pools, and tested for arboviruses and coronaviruses by using RT-PCR with the help of specific primers. Novel Coronavirus was not detected in this study. Only the Flavivirus genus was detected in twenty-seven pools giving an infection rate of 62.96% (n = 17) for DENV2, while DENV3 was 37.03% (n = 10). Furthermore, our results indicated no role of mosquitoes in the spread of Covid-19. Results showed a higher infection rate in urban sites than in rural ones. The detection of arboviruses indicates possible human health risk due to active role of these mosquitoes in spreading of arbovirus in the study area.

Efficacy of Probiotics Supplementation on Growth Performance, Carcass Composition and Hematological Parameters of Cyprinus carpio Fingerlings Fed Corn Gluten Meal-Based Diet

Abstract Plant based protein sources are one of the best, cost effective and easily available protein sources being used in fish feed. But due to a lower number of micro-biota in fish gut plant meal based diets cannot be digested and absorbed well in fish body. Probiotics were supplemented at 0, 1, 2, 3, 4 and 5 gkg-1 levels in fish feed for formulating one control and five test diets. In this study, three replicates of each treatment were used and number of fingerlings was 15 in each replicate. The C. carpio (common carp) fingerlings were fed at 5% of live wet weight on their prescribed diet twice daily. The results revealed that supplementation of probiotics in corn gluten meal based diets significantly (p<0.05) improved growth performance, carcass composition and hematological parameters. Most optimum values of growth performance parameters were noted at 2 gkg-1 level of probiotics supplemented diet. C. carpio fingerlings fed corn gluten meal based diet supplemented with 2 gkg-1 level of probiotics indicated significant (p<0.05) improvements in crude protein (17g) crude fat (9g) and gross energy (3 kcalg-1) whereas higher red blood cells (RBCs), white blood cells (WBCs) and hemoglobin (Hb) was also recorded in fish blood when fed 2 gkg-1 probiotics level diet. From these results, it was concluded that 2 gkg-1 probiotics supplementation in corn gluten meal based diet is optimum for improving growth performance, body composition and hematology of C. carpio fingerlings.

Evaluation of Larvicidal Efficacy of Ricinus communis (Castor) Plant Extract and Synthesized Green Silver Nanoparticles against Aedes albopictus.

BACKGROUND: Aedes mosquitoes are the most important group of vectors having ability of transmitting pathogens including arboviruses that can cause serious diseases like Chikungunya fever, Dengue fever and Zika virus in human. Biosynthesis and the use of green silver nanoparticles (AgNPs) is an important step in the search of reliable and ecofriendly control of these vectors. METHODS: In this study an aqueous leaves extract of Ricinus communis (castor) and silver nanoparticles (AgNPs) synthesized from this extract were evaluated as larvicidal agent for 2nd and 3rd instar larvae of the Aedes albopictus. Different concentrations (50, 100, 150, 200 and 250ppm) of plant extract and synthesized nanoparticles were prepared and applied on second and third instar larvae. The percent mortality was noted after 6, 12, 18, 24, 30, 36, 42 and 48H of exposure and subjected to probit analysis to calculate LC50 and LC90. RESULTS: Synthesized Ag+ nanoparticles were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR), and energy-dispersive X-ray spectroscopy (XRD). The nanoparticles were more toxic against larvae of Ae. albopictus with LC50 value (49.43ppm) and LC90 value (93.65ppm) for 2nd instar larvae and LC50 (84.98ppm) and LC90 (163.89ppm) for 3rd instar larvae as compared to the plant extract (149.58ppm, 268.93ppm) and (155.58ppm, 279.93ppm) for 2nd and 3rd instar larvae of Ae. albopictus respectively after 48H. CONCLUSION: Our results suggest the extract of R. communis and synthesized nanoparticles as excellent replacement of chemical pesticides to control the vector mosquitoes.

Evaluation of larvicidal efficacy of Ricinus communis (Castor) and synthesized green silver nanoparticles against Aedes aegypti L.

Aedes mosquitoes are the most important group of vectors that transmit pathogens, including arboviruses, and cause human diseases such as dengue fever, yellow fever, Zika virus, and Chikungunya. Biosynthesis and the use of green silver nanoparticles (AgNPs) is a vital step to identify reliable and eco-friendly controls for these vectors. In this study, Aedes (Ae.) aegypti larvae (2nd and 3rd instar) were exposed to leaf extracts of Ricinus communis (Castor) and AgNPs synthesized from the extract to evaluate their larvicidal potential. Synthesized AgNPs were characterized by UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), and energy-dispersive X-ray spectroscopy (XRD). Ae. aegypti larvae were treated with different concentrations (50-250 ppm) of the leaf extract and synthesized AgNPs. There were five replicates per treatment, in addition to a positive (temephos) and negative control (dechlorinated water). Mortality was recorded after 12, 24, 36, and 48 h and the data were subjected to Probit analysis. The nanoparticles were more toxic (LC50 = 46.22 ppm and LC90 = 85.30 ppm) than the plant extract (106.24 and 175.73 ppm, respectively). The leaf extracts of Ricinus communis were subjected to HPLC analysis to identify their chemical constituents. This study suggests that plant extracts and synthesized nanoparticles are excellent alternatives to hazardous chemical pesticides used to control vector mosquitoes. This is a potentially useful technique that can reduce aquatic toxicity from insecticide use.

Effect of Climatic Conditions and Water Bodies on Population Dynamics of the Dengue Vector, Aedes aegypti (Diptera: Culicidae).

BACKGROUND: The population of mosquitoes is mainly influenced by the biotic and abiotic factors. Although Aedes aegypti was reported until 1960's in the Punjab, Pakistan, the population has increased dramatically since 2009 and caused severe epidemics in 2011 due to heavy floods and rains. Thus, this study was carried out to know the effect of biotic and abiotic factors on the population of Aedes aegypti. METHODS: Mosquitoes were collected from fresh, sewage, and rain water ponds, fish ponds, rice fields, tyres, tree holes, and manmade storage containers present in and around residential homes twice during every winter (October-February), summer (March-June) and monsoon season (July-September) from marked rural areas. RESULTS: More mosquitoes were collected in 2010 and 2011 due to floods than other years with heavy rains. High population (52.4%) was recorded during the rainy season due to high temperature (28-36 °C) and high relative humidity (up to 75%), while low population was recorded during the winter due to low temperature (< 5 °C) and low relative humidity (< 22%). Specimens were recorded indoors when outside temperature was below freezing point. Ae. aegypti was largely collected from tyres and urban areas mostly during the rainy season from small water containers. Years, months, seasons, temperature and relative humidity were statistically significant concerning the population dynamics of mosquitoes. CONCLUSION: Abiotic factors (temperature & relative humidity) along with habitat have significant impact on population dynamics of mosquitoes.

Genetic Analysis of Aedes aegypti Using Random Amplified Polymorphic DNA (RAPD) Markers from Dengue Outbreaks in Pakistan.

BACKGROUND: Keeping in view the havoc situation of dengue fever in Pakistan, the current study was designed to demonstrate the genetic variations, gene flow and rate of migration from Lahore and Faisalabad. METHODS: The larvae were collected from both natural and artificial breeding places from each collection site. The adult mosquitoes were collected by means of sweep net and battery-operated aspirator. DNA extraction was performed using TNE buffer method. Ten GeneLink-A series RAPD primers were used for PCR amplification and the data was analyzed through POPGENE. RESULTS: The number of amplification products produced per primer varied from 8-12, ranging from 200 to 2000 bp with an average of 10.0 bands per primer. The percentage of polymorphic loci amplified by each primer varied from 22.5 to 51%. The UPGMA dendrogram demonstrates two distinct groups from Faisalabad and Lahore populations. The genetic diversity ranged from 0.260 in Faisalabad to 0.294 in Lahore with a total heterozygosity of 0.379. The GST value for nine populations within Lahore was 0.131 (Nm= 3.317), whereas for nine populations in Faisalabad GST value was 0.117 (Nm= 3.773). The overall genetic variation among eighteen populations showed GST= 0.341 and Nm= 1.966. CONCLUSION: The genetic relatedness and Nm value show that Ae. aegypti populations exhibit intra-population gene flow both in Faisalabad and Lahore. Although, both cities show a distinct pattern of genetic structure; however, few areas from both the cities show genetic similarity. The gene flow and the genetic relatedness in few populations of Lahore and Faisalabad cities need further investigation.

Paederus beetles: the agent of human dermatitis.

BACKGROUND: Rove beetles of the genus Paederus cause dermatitis when they come in contact with human skin. This condition is prevalent in some tropical and subtropical regions, such as in northern Pakistan, where it was recorded for the first time by US troops. Despite much research from other countries on this subject, few studies, mostly clinical, have been performed in a Pakistani context. A survey was carried out in villages, towns and cities of Punjab province, Pakistan, to explore the rove beetle population dynamics and to develop a model to elucidate the symptoms, preventive measures and treatment strategies for this dermatitis. METHODS: The prospective observational and patient surveys were performed bimonthly over a period of two years, in different districts of Punjab province. Collection was carried out in fields, gardens and houses during every visit with the aid of a pitfall trap, light trap, flight intercept trap, Berlese funnel trap and sweep netting. These traps were installed for four days during every visit. Interviews of ten individuals of different ages and sexes from each site were recorded during each visit. RESULTS: Out of 980 individuals, 26.4% were found to suffer from Paederus dermatitis. Lesions were most commonly found on the neck followed by the face. In July-August during the rainy season, this skin irritation was most prevalent and the population of these beetles peaked (36.2%). During May-June, the beetle population was lowest (7.85%) due to soil dryness. About 70% of such irritation cases were from individuals living in farming villages or in farmhouses. Their houses typically (80%) had broken doors and screen-less windows while 97% of the residents were unaware of how they may have come into contact with these beetles. In most cases (91% from villages/small towns and 24% from cities and adjoining areas) the local residents were unaware of modern treatment strategies. CONCLUSIONS: Paederus dermatitis is extremely frequent in villages with poor housing facilities and could be avoided via community awareness.

Paederus beetles: the agent of human dermatitis

Background Rove beetles of the genus Paederus cause dermatitis when they come in contact with human skin. This condition is prevalent in some tropical and subtropical regions, such as in northern Pakistan, where it was recorded for the first time by US troops. Despite much research from other countries on this subject, few studies, mostly clinical, have been performed in a Pakistani context. A survey was carried out in villages, towns and cities of Punjab province, Pakistan, to explore the rove beetle population dynamics and to develop a model to elucidate the symptoms, preventive measures and treatment strategies for this dermatitis. Methods The prospective observational and patient surveys were performed bimonthly over a period of two years, in different districts of Punjab province. Collection was carried out in fields, gardens and houses during every visit with the aid of a pitfall trap, light trap, flight intercept trap, Berlese funnel trap and sweep netting. These traps were installed for four days during every visit. Interviews of ten individuals of different ages and sexes from each site were recorded during each visit. Results Out of 980 individuals, 26.4% were found to suffer from Paederus dermatitis. Lesions were most commonly found on the neck followed by the face. In July-August during the rainy season, this skin irritation was most prevalent and the population of these beetles peaked (36.2%). During May-June, the beetle population was lowest (7.85%) due to soil dryness. About 70% of such irritation cases were from individuals living in farming villages or in farmhouses. Their houses typically (80%) had broken doors and screen-less windows while 97% of the residents were unaware of how they may have come into contact with these beetles. In most cases (91% from villages/small towns and 24% from cities and adjoining areas) the local residents were unaware of modern treatment strategies. Paederus dermatitis is extremely frequent in villages with poor housing facilities and could be avoided via community awareness.(AU)