Non-biting Flies Research Articles

African swine fever virus DNA is present in non-biting flies collected from outbreak farms in Romania

BackgroundAfrican swine fever (ASF) is a highly contagious and severe haemorrhagic disease of Suidae, with mortalities that approach 100 percent. Several studies suggested the potential implication of non-biting dipterans in the spread of ASFV in pig farms due to the identification of the ASFV DNA. However, to our knowledge, no study has evaluated the viral DNA load in non-biting dipterans collected in outbreak farms and no risk factors have been analysed. In this context, our study aimed to analyse the risk factors associated with the presence of non-biting dipterans collected from ASF outbreaks in relation to the presence and load of viral DNA.MethodsBackyard farms (BF), type A farms (TAF), and commercial farms (CF), were targeted for sampling in 2020. In 2021, no BF were sampled. Each farm was sampled only once. The identification of the collected flies to family, genus, or species level was performed based on morphological characteristics using specific keys and descriptions. Pools were made prior to DNA extraction. All extracted DNA was tested for the presence of the ASFV using a real-time PCR protocol. For this study, we considered every sample with a CT value of 40 as positive. The statistical analysis was performed using Epi Info 7 software (CDC, USA).ResultsAll collected non-biting flies belonged to five families: Calliphoridae, Sarcophagidae, Fanniidae, Drosophilidae, and Muscidae. Of the 361 pools, 201 were positive for the presence of ASFV DNA. The obtained CT values of the positive samples ranged from 21.54 to 39.63, with a median value of 33.59 and a mean value of 33.56. Significantly lower CT values (corresponding to higher viral DNA load) were obtained in Sarcophagidae, with a mean value of 32.56; a significantly higher number of positive pools were noticed in August, mean value = 33.12.ConclusionsOur study brings compelling evidence of the presence of the most common synanthropic flies near domestic pig farms carrying ASFV DNA, highlighting the importance of strengthening the biosecurity measures and protocols for prevention of the insect life cycle and distribution.Graphical

Highlights of Veterinary Entomology, 2022.

The field of veterinary entomology is dominated by research concerning insects and arthropods that negatively impact the health of domestic animals. A curated selection of peer-reviewed research which was highlighted at the 2022 Joint Meeting between the Entomological Society of America, the Entomological Society of Canada, and the Entomological Society of British Columbia, which prioritized exploring entomology through the lens of art, science, and culture are summarized. Articles are categorized into (i) biting and non-biting flies, (ii) ectoparasites, and (iii) review articles, with the overall goal of showcasing innovative methodologies, addressing overlooked questions in veterinary entomology, and highlighting comprehensive reviews. While not exhaustive, the selected studies represent a myriad of arthropods, methodologies, and perspectives, to inspire future scientists with diverse research avenues and emphasize the continual evolution and importance of entomological studies in today's world.

Comparative mitogenome analyses of twelve non-biting flies and provide insights into the phylogeny of Chironomidae (Diptera: Culicomorpha)

The family Chironomidae is represented by seven subfamilies in China, among which Chironominae and Orthocladiinae are the most diverse. To gain a better understanding of the architecture and evolution of the mitogenomes of Chironomidae, we sequenced mitogenomes of twelve species (including two published species) of the two subfamilies Chironominae and Orthocladiinae, and comparative mitogenomic analyses were performed. Thus, we identified highly conserved genome organization of twelve species with regard to genome content, nucleotide and amino acid composition, codon usage, and gene characteristics. The Ka/Ks values of most protein-coding genes were far smaller than 1, indicating that these genes were evolving under purifying selection. Phylogenetic relationships between the family Chironomidae were reconstructed using 23 species representing six subfamilies, based on protein-coding genes and rRNAs using Bayesian Inference and Maximum Likelihood. Our results suggested the following relationship within the Chironomidae: (Podonominae + Tanypodinae) + (Diamesinae + (Prodiamesinae + (Orthocladiinae + Chironominae))). This study contributes to the mitogenomic database of Chironomidae, which will be significant for studing the mitogenome evolution of Chironomidae.

No Evidence of SARS-CoV-2 Among Flies or Cockroaches in Households Where COVID-19 Positive Cases Resided

Flies and other arthropods mechanically transmit multiple pathogens and a recent experimental study demonstrated house flies, Musca domestica L. (Diptera: Muscidae), can mechanically transmit SARS-CoV-2. The purpose of this study was to explore the possibility of mechanical transmission of SARS-CoV-2 by domestic insects and their potential as a xenosurveillance tool for detection of the virus. Flies were trapped in homes where at least one confirmed human COVID-19 case(s) resided using sticky and liquid-baited fly traps placed inside and outside the home in the Texas counties of Brazos, Bell, and Montgomery, from June to September 2020. Flies from sticky traps were identified, pooled by taxa, homogenized, and tested for the presence of SARS-CoV-2 RNA using quantitative reverse transcription PCR (RT-qPCR). Liquid traps were drained, and the collected fluid similarly tested after RNA concentration. We processed the contents of 133 insect traps from 40 homes, which contained over 1,345 individual insects of 11 different Diptera families and Blattodea. These individuals were grouped into 243 pools, and all tested negative for SARS-CoV-2 RNA. Fourteen traps in seven homes were deployed on the day that cat or dog samples tested positive for SARS-CoV-2 RNA by nasal, oral, body, or rectal samples. This study presents evidence that biting and nonbiting flies and cockroaches (Blattodea) are not likely to contribute to mechanical transmission of SARS-CoV-2 or be useful in xenosurveillance for SARS-CoV-2.

Human Ocular Thelaziasis: A Case Report

Thelaziasis is a zoonotic disease which affects the eye of domestic and wild carnivores caused by the nematode Thelazia. It is transmitted to humans by secretophagous arthropod-borne zoophilic nonbiting flies of the family Drosophilidae. Human thelaziasis is rare and occurs in poor socio-economic families of the rural locations where people live in close proximity with animals. A one and halfyear-old was presented to the outpatient ophthalmology clinic after her mother noticed a whitish, thread-like worm in her right eye. A total of four worms were mechanically removed from her right eye. All the collected worms were gravid female nematodes of Thelazia species. The present case of human ocular thelaziasis from Palpa, Nepal is presented for its rarity.

Analysis of vaccine-like lumpy skin disease virus from flies near the western border of China.

Lumpy skin disease (LSD) is a devastating viral disease that occurs in cattle. In China, it was first detected in the Xin-Jiang autonomous region, near the border with Kazakhstan, in August 2019. As there were no new occurrences of LSD in either country following the first detection, the initial introduction of the virus remains unknown. Arthropod vectors were considered as potential vectors. Consequently, to identify the arthropod vectors involved in transmitting LSD virus (LSDV), an insect surveillance campaign was launched at four different sites scattered along the border, and samples from 22 flying insect species were collected and subjected to PCR assays. Following the Agianniotaki LSDV vaccine and Sprygin's general LSDV assays, two kinds of non-biting flies, namely, Musca domestica L and Muscina stabulans, were positive for LSDV. However, all the other insects tested negative. Viral DNA was only detected in wash fluid, implying body surface contamination of the virus. The negative test results suggest that non-biting flies are the dominant insects involved in the observed local epidemic. Three genomic regions encoding RPO30, GPCR, and LW126 were successfully sequenced and subjected to phylogenetic analysis. The sequences shared high homology with LSDV/Russia/Saratov/2017, a recombinant vaccine-like strain formerly identified in Russia, and clustered with LSDV vaccine strains in phylogenetic trees of RPO30 and LW126. However, the GPCR gene was seen to be solely clustered with LSDV field strains, implying differences in host affinity between these closely related vaccine-like strains. Despite this, there is no direct evidence to support cross-border transmission of the vaccine-like LSDV. To our knowledge, this is the first report of vaccine-like LSDV DNA detection in non-biting flies in China.

Public Health and Medically Important Non-Biting Flies in Hail, Saudi Arabia

Public Health and Medically Important Non-Biting Flies in Hail, Saudi Arabia

Experimental and field investigation of non-biting flies as potential mechanical vectors of Echinococcus granulosus eggs

Synanthropic fly species can be potential mechanical vectors of many infectious agents. The potential of the flies to carry Echinococcus granulosus eggs is not fully documented. The purpose of the present study was to determine the possible role of non-biting flies to carry taeniid eggs. A total of 210 flies were collected from seven selected sites in areas of Kerman city, southeastern Iran from November 2016 to May 2017. Adult flies were live-caught using sweeping nets. Flies were placed individually in small glass bottles and transported to the laboratory. All the flies were killed by deep freezing and then identified to the species level using both morphological and molecular methods. The flies were homogenized in test tubes and genomic DNA was extracted and amplified by PCR. PCR protocols were used both to identify the live-caught flies to the species level, and for the detection of E. granulosus. The laboratory reared second generation flies were experimentally exposed to dog feces manually spiked by Echinococcus eggs. Two runs of experiments with 1–3 h of exposure were designed. For each experiment 20 flies were selected from the stock colony and were starved for three days. After each experiment, the flies were frozen for further molecular studies. The dominant fly species were Musca domestica and Lucilia sericata. No eggs were found on the body surface and/or guts of live-caught flies. After the first hour of exposure, 60%, of the flies of both species were found to harbor Echinococcus eggs. However, in the case of L. sericata 50% of the flies harbored Echinococcus eggs after 3 h of exposure. Results of the present study indicate the probable role of synanthropic flies in harboring Echinococcus eggs and mechanical transmission of cystic echinococcosis. When the helminth eggs are susceptible to desiccation grooming flies can remove many of eggs from exterior surfaces of them. Despite this result the role of synanthropic flies in the transmission of certain helminthiases should not be discounted because of their vagility and feeding mechanisms.

Projected economic losses due to vector and vector-borne parasitic diseases in livestock of India and its significance in implementing the concept of integrated practices for vector management.

Broadly, species of arthropods infesting livestock are grouped into flies (biting and non-biting), fleas, lice (biting and sucking), ticks (soft and hard), and mites (burrowing, non-burrowing, and follicular). Among which, biting and non-biting flies and ticks are the potent vectors for many bacterial, viral, rickettsial, and protozoan diseases. Vectors of livestock are having economic significance on three points (1) direct losses from their bite and annoyance, worries, and psychological disturbances produced during the act of biting and feeding, (2) diseases they transmit, and (3) expenditure incurred for their control. Flies such as Culicoides spp. and Musca spp. and various species of hard ticks play important role in disease transmission in addition to their direct effects. For control of vectors, recent concept of integrated pest management (IPM) provides the best solution and also addresses the problems related to acaricide resistance and environmental protection from hazardous chemicals. However, to successfully implement the concept of IPM, for each vector species, estimation of two monitory benchmarks, i.e., economic injury level (EIL) and economic threshold level (ETL) is essential prerequisite. For many vector species and under several circumstances, estimation of EIL and ETL appears to be difficult. Under such scenario, although may not be exact, an approximate estimate can be accrued by taking into account several criteria such as percent prevalence of vectors in a geographical area, percent losses produced, total livestock population, and current prices of livestock products such as milk, meat, and wool. Method for approximate estimation is first time described and elaborated in the present review article.

Field evaluation of a semi-automatic funnel trap targeted the medically important non-biting flies

Bait-trapping is a useful approach for monitoring fly population dynamics, and it is an effective tool for physical control of pest species. The aim of this study was to test a newly developed semi-automatic funnel fly trap with some modifications of the former prototype fly trap to study medically important fly population density. The efficacy of the semi-automatic funnel trap was assessed by field sampling during July 2013-June 2014 using 1-day tainted beef offal as bait. The modified semi-automatic funnel traps were able to capture a total of 151,141 adult flies, belonging to the families: Calliphoridae (n=147,248; 97.4%), Muscidae (n=3,124; 2.1%) and Sarcophagidae (n=769; 0.5%), which are the medically important fly species. Among the total of 35 species collected, Chrysomya megacephala (Diptera: Calliphoridae) (n=88,273; 59.95%), Musca domestica (Diptera: Muscidae) (n=1,324; 42.38%) and Boettcherisca peregrina (Diptera: Sarcophagidae) (n=68; 33.01%) were the predominant species of each family. High number of flies was captured in forest area, representing 42.47% (n=64,197) of total specimens. Female flies were trapped more than male with total sex ratio of 0.37 male/female. Flies were trapped throughout the year with peak population in summer. Peak activity was recorded in the afternoon (12.00–18.00h). In summary, the modified semi-automatic funnel fly trap can be used for field collection of the adult fly. By setting the timer, population dynamics, diversity, and periodic activity of adult flies were determined.

Low potential for mechanical transmission of Ebola virus via house flies (Musca domestica)

BackgroundEbola virus (EBOV) infection results in high morbidity and mortality and is primarily transmitted in communities by contact with infectious bodily fluids. While clinical and experimental evidence indicates that EBOV is transmitted via mucosal exposure, the ability of non-biting muscid flies to mechanically transmit EBOV following exposure to the face had not been assessed.ResultsTo investigate this transmission route, house flies (Musca domestica Linnaeus) were used to deliver an EBOV/blood mixture to the ocular/nasal/oral facial mucosa of four cynomolgus macaques (Macaca fascicularis Raffles). Following exposure, macaques were monitored for evidence of infection through the conclusion of the study, days 57 and 58. We found no evidence of systemic infection in any of the exposed macaques.ConclusionsThe results of this study indicate that there is a low potential for the mechanical transmission of EBOV via house flies - the conditions in this study were not sufficient to initiate infection.

Frequency (Occurrence) and seasonal variation of bacterial species on the external surface of non-biting flies in Egypt

Frequency (Occurrence) and seasonal variation of bacterial species on the external surface of non-biting flies in Egypt

Flies and Yaws: Molecular Studies Provide New Insight

Flies and Yaws: Molecular Studies Provide New Insight

Prevalence of biting and non-biting flies in relation to species in the Jos Museum Zoological Garden, north central Nigeria

Several Dipteran flies are vectors of diseases in the Afro-tropical region. The study was carried out to determine the species abundance of biting and non biting flies prevalent at the Jos Museum Zoological Garden, north central Nigeria. The flies were trapped using Biconical traps during the raining season of August -September 2013. The flies were harvested three times a week at an interval of 48 hours. Stomoxys calcitrans is the most abundant species trapped. There were significantly more flies in the Lion, Bovidae (Donkey, Carmel and Horse) and Ostrich sites compared to Human routes, Chimpanzee and Hyena sites suggesting a correlation between flies abundance and body size of animal. Flies proportions were compared using Chi-square test. There is a significant difference in the abundance of biting and non-biting flies. There is also a significant difference in the abundance of flies in relation to species and trapping sites. The biting effects on resident animals and tourists were discussed. The Jos Museum Zoological Garden being the oldest and second largest tourist destination in Nigeria will require concerted efforts to put in proper control measures to prevent flies infestation. This can be done through improved hygienic conditions and wastes management.Key words: Biting, flies, Garden, Museum, Zoological

Failure of Sterne- and Pasteur-like strains of Bacillus anthracis to replicate and survive in the urban bluebottle blow fly Calliphora vicina under laboratory conditions.

This study aimed to elucidate the bacteriological events occurring within the gut of Calliphora vicina, selected as the European representative of blow flies held responsible for the spread of anthrax during epidemics in certain parts of the world. Green-fluorescent-protein-carrying derivatives of Bacillus anthracis were used. These lacked either one of the virulence plasmids pXO1 and pXO2 and were infected, or not infected, with a worm intestine phage (Wip4) known to influence the phenotype and survival of the pathogen. Blood meals were prepared for the flies by inoculation of sheep blood with germinated and, in case of pXO2+ strains, encapsulated cells of the four B. anthracis strains. After being fed for 4 h an initial 10 flies were externally disinfected with peracetic acid to ensure subsequent quantitation representing ingested B. anthracis only. Following neutralization, they were crushed in sterile saline. Over each of the ensuing 7 to 10 days, 10 flies were removed and processed the same way. In the absence of Wip4, strains showed steady declines to undetectable in the total B. anthracis counts, within 7–9 days. With the phage infected strains, the falls in viable counts were significantly more rapid than in their uninfected counterparts. Spores were detectable in flies for longer periods than vegetative bacteria. In line with the findings in both biting and non-biting flies of early workers our results indicate that B. anthracis does not multiply in the guts of blow flies and survival is limited to a matter of days.

The Diet of the Pond BatMyotis dasycnemeand Its Seasonal Variation in a Forested Lakeland of Northern Poland

The diet of the Central European trawling vespertilionid, the pond bat Myotis dasycneme, was studied in a nursery roost in the postglacial lakeland of northern Poland , based on a very large (n = 1,725) sample of faecal pellets. This is only the third published dietary study of the species, considered to have a high conservation priority in Europe. Pond bats'prey was dominated by non-biting midges (Chironomidae — both imagines and pupae) and caddis flies (Trichoptera). However, the spectrum of prey was relatively broad, with 16 taxa, including 12 recorded for the first time in the diet of M. dasycneme. Frequency of occurrence (0%) of particular taxa varied through the season. 0% of caddis flies and non-biting midges in droppings were negatively correlated (rs= -0.75, P < 0.05); exceptionally high 0% of caddis flies, being larger (and presumably more profitable) prey, occurred in late June and July, coinciding with high energy demands of lactating females. No evidence of piscivory was revealed.

External Parasites on Horses

Arthropod parasites of horses include internal bots that infest the digestive tract, mites that burrow in the skin and feed on the skin surface, ticks that infest the ears as well as the skin, lice that either suck blood or feed on skin, blood sucking flies and mosquitoes that range in size from biting gnats just observable with the naked eye to the large black horse flies which are almost one inch long. Non-biting flies such as house flies and face flies are also important in producing fly worry, irritation and disease transmission. This document is ENY-283 (IG139), one of a series of the Entomology and Nematology Department, UF/IFAS Extension. Original publication date May 1980. Revised March 2006. ENY-283/IG139: External Parasites on Horses (ufl.edu)

External Parasites Around Animal Facilities

Several kinds of non-biting flies can be found in and around animal facilities. These flies can be harmful to animal health and cause annoyance and discomfort. This document is ENY-255 (IG054), one of a series of the Department of Entomology and Nematology, UF/IFAS Extension. Original publication date June 1993. Revised March 2006. ENY-255/IG054: External Parasites around Animal Facilities (ufl.edu)

A review and case reports of parasitic arthropods infesting local poultry and their roles in the transmission of haemoparasites in Nigeria

Observation of a persistent infestation of turkeys by Stomoxys sp during the day and mosquitoes at night prompted this investigation. Turkeys were mostly infested by Stomoxys calcitrans (74.5%) during the day and by Culex pipiens (15.0%) at night. Plasmodium sp (5.8%) and Haemoproteus (0.1%) were transmitted by these species of flies. Other arthropods identified infesting turkeys included Haematobium sp (3.5%), Simulium sp (2.0%), Aedes sp (1.0%), Culicoides sp (0.2%) and the biting lice Menacanthus stramineus (2.5%). The most common fly species recorded around chickens were the non-biting fly Musca domestica (60.5%) during the day, and Culex pipiens (15.5%) at night. Infesting lice were M. stramineus (17.0%) and oniodes gigas (3.0%). Culicoides sp represented only 1.0% of infestation. Plasmodium sp (2.4%) was the only haemoparasite seen in blood samples examined from chicken. Pigeons were mainly infested by Pseudolynchia canariensis (85.8%) by day and Culex pipiens (12.5%) at night. M. domestica represented only 1.7%. Haemoparasites identified from the blood samples of pigeons were Haemoproteus sp (2.2%) and Plasmodium sp (0.8%). M. domestica (95.0%) and Drosophila melanogaster (5.0%) were the only flies caught around ducks. Both flies are not blood-sucking. No haemoparasite was identified from the blood samples examined. The blood sucking activity of these parasites resulted in irritation and the development of anaemia, leading to production losses due to morbidity and mortality. Keywords : diptera, haemoparasites, poultry Tropical Veterinarian Vol. 22(2) 2004: 61-71

Learning to cope with biting flies: Rapid NMDA-mediated acquisition of conditioned analgesia.

A 30-min exposure to intact biting flies (stable flies) induced an opioid-mediated analgesia in fly-naive male deer mice, whereas exposure to either altered biting flies whose biting mouthparts were removed or nonbiting house flies had no significant effects. However, mice that were previously exposed to intact stable flies for 30 min exhibited significant analgesia when exposed 24-168 hr later to stable flies whose biting parts were removed, but not to nonbiting house flies. Administration of the specific N-methyl-D-aspartate (NMDA) antagonist NPC 12626 to fly-naive mice before exposure to intact flies, although not significantly reducing the analgesic response, blocked the subsequent conditioned analgesia. Naloxone, which blocked the intact biting fly-induced analgesia, did not alter the acquisition of the conditioned analgesic response to the altered stable flies. This demonstrates an NMDA-mediated acquisition of conditioned analgesia to a natural aversive stimulus.