Odonata larvae as a bioindicator of metal contamination in aquatic environments: application to ecologically important wetlands in Iran

Monitoring of hard tick parasitism in domestic ruminants: A scale evidence for policymakers

Domestic ruminants such as camels, cattle, goats, and sheep represent a substantial part of the global world economy. Hard ticks are well-known as obligatory bloodsucking ectoparasites of domestic ruminants. Policymakers need to get results that show the global distribution of tick genera and species, their parasitic levels, and their roles as disease vectors in camels, cattle, goats, and sheep. Iran is endemic to a broad range of hard tick-borne diseases. A study that reviews the tick genera and species, life stage, seasonal and attachment site parasitism levels, the global mean ranks of tick species parasitism rates and records, and their distribution in target animals would be of particular importance. Accordingly, this review aims to summarize the above objectives. After evaluating the identified articles, 147 were selected to be part of the survey based on the study objectives. Globally, tick parasitism levels were 28.7, 29.9, 36.0 and 47.6% for goats, cattle, sheep, and camels, respectively. The tick parasitism trends have exhibited an increasing trend for camels and sheep over the years while remaining constant for cattle and goats, indicating that current tick control measures are not being properly followed. Ticks tend to parasitize females more than males because males are more resistant to certain pests than females. The distribution of tick genera and species, their parasitism levels, and their roles as disease vectors provided. This information addresses the needs of decision-makers to make decisions.

Nutritional Compositions of Aquatic Insects Living in Rice Fields, with a Particular Focus on Odonate Larvae

Although the human consumption of aquatic insects is prevalent in many regions, the nutritional composition of the insects has not been comprehensively determined. The proximate composition of Pantala sp. was shown to be a good source of protein (49.45 ± 0.32 g/100 g DW), as well as of minerals such as sodium, calcium, potassium, phosphorus, zinc, and iron. All nine essential amino acids are present in this species, with valine being the most abundant. The major fatty acids are palmitic acid (1.19 ± 0.02 g/100 g DW), oleic acid (0.63 ± 0.02 g/100 g DW), and linoleic acid (0.55 ± 0.01 g/100 g DW). Lead (Pb), arsenic (As), and cadmium (Cd) showed a value of 0.18 ± 0.01 mg·kg^-1, 3.51 ± 0.12 mg·kg^-1, and 0.17 ± 0.00 mg·kg^-1, respectively. Furthermore, microplastic (MP) contamination in odonate larvae (419 individuals belonging to three identified families) was found in varying shapes, e.g., fibers, fragments, and rods. FTIR analysis revealed the following MP polymers, polyethylene terephthalate, polyvinyl acetate, bis(2-ethylhexyl), polybutadiene, poly(methyl methacrylate-co-methacrylic acid); P(MMA-co-MA), poly(ethylene glycol) tetrahydrofurfuryl ether, poly(acrylonitrile-co-butadiene), and polypropylene glycol. The results of this work could be a nutritional reference for food security and the risk of eating insects.

Detailed Infestation Spectrums About Biological Stages of Hard Ticks (Acari: Ixodida: Ixodidae) in Humans: A Systematic Review and Meta-Analysis

PURPOSE

A comprehensive systematic meta-analysis review which deals with the degrees and trends of human infestation by biological stages of ticks, the degrees and trends of human infestation by biological stages of ticks in rural and urban areas, the infestation scale of tick attachment sites in body parts of humans, and the degrees of tick infestation in human age groups is critical. Therefore, this systematic meta-analysis review summarizes the above-detailed human infestation spectrums about biological stages of hard ticks.

METHODS

After a preliminary review from 605 papers representing areas of the study objectives, 96 were selected for detailed human infestation spectrums of biological stages of hard ticks.

RESULTS

In general, the results suggest that the adult ticks, and mostly females attack humans more than larval and nymphalid ones, and adult males, respectively. Unlike the trends of human infestation by larval and nymphalid stages of ticks, and the adult, male and female ticks which exhibited approximately a sharply decreasing trend, the global trend of human infestation by hard ticks exhibited approximately a sharply increasing trend over time. Ticks attack humans more in rural area than urban area. Also, the trends of human tick infestation in rural and urban areas exhibit, respectively, a sharp increase and decrease trends over time.

CONCLUSIONS

The majority of ticks mostly attach to human body trunk and extremity than head and neck, and genital area. Ticks attack human age groups of 0-9, 20-39, and 40-59 years more than those aged between 10 and 19 or older than 60 years.

Preliminary Assessment of Chemical Elements in Sediments and Larvae of Gomphidae (Odonata) from the Blyde River of the Olifants River System, South Africa

Benthic macroinvertebrates and sediments can act as good indicators of environmental quality. The aim of this study was to assess the accumulation of chemical elements in the Gomphidae (Odonata) collected in the Blyde River. Seven sites were sampled for river sediments assessment and five sites for larvae (naiads) of Gomphidae bioaccumulation analysis. The tissue samples were analysed using inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed high levels of all of the tested elements except Cd in the sediment. The mean concentrations of As, Cu and Cr exceeded the standard guideline values, whereas Pb and Zn were below the standard guideline values. In the insect body tissue, the concentrations of most elements were higher than in the sediments. The elements with the highest concentrations were Mn, Zn, Cu, and As. The bioaccumulation factor (BF) showed a tendency for bioaccumulation for almost all of the selected elements in the insect. The BF value was high for Cu, Mn, Sb, and Zn (BF > 1). The high concentrations of elements in the insect body tissue may pose a risk to fish that consume them, and subsequently to humans when fish from the river are consumed. It is therefore important to monitor the river to reduce pollution to prevent health risks in humans, especially in communities that rely on the river for water and food.

New aspects about Crimean-Congo hemorrhagic fever (CCHF) cases and associated fatality trends: A global systematic review and meta-analysis

Crimean-Congo hemorrhagic fever (CCHF) is the most popular tick-borne disease causing by Crimean-Congo hemorrhagic fever virus (CCHFV). There are several valuable reviews considering some fields of the CCHF aspects. While there is no a systematic review about means and trends of CCHF cases and fatality rate, means and trends of CCHF cases and fatality rates of human occupations involved in CCHF. Therefore, this meta-analysis review performed to highlight and provide a global detailed of the above CCHF aspects. Among 398 collected papers, 173 papers were become this meta-analysis review. The study results confirm that an apparent increasing CCHF cases occurred through the past decades. The trends of annually and periodically CCHF cases and fatality rates were also increased. The means of annually and periodically CCHF cases and fatality rates were 57 and 432 cases, and 10 cases and 32.2 % and 49 cases and 28.8 %, respectively. The means of annually and periodically CCHF fatality rates are about one-tenth of CCHF human cases. The mean of CCHF fatality rates in Africa (22.0 %) is lower than Asia (33.5 %) and Europe (33.8 %). Among occupations involved in CCHF, agricultural (28.9 %), health-care (19.2 %) and slaughterhouse (16.7 %) workers, and farmers (13.9 %) had the maximum CCHF fatality rates in order. Based on literature review of CCHFV S-segment aspects, several clades and genotypes are reported to distribute in Africa, Asia and Europe regions. There are very wide fields to investigate the epidemiology characteristics of CCHFV clades, genotypes and their distribution in the future.

Environmental-friendly Contamination Assessment of Habitats Based on the Trace Element Content of Dragonfly Exuviae

We tested the usefulness of exuviae as an environmentally friendly method for exploring the variability of the trace element contents of protected insect populations without killing specimens. It is a notable characteristic of dragonflies that they are good ecological indicators for both aquatic and terrestrial habitat quality. Thus, we investigated the trace element accumulation in different stages of dragonflies: larva, exuvia, and adult. Using microwave plasma atomic emission spectrometry (MP-AES), we analysed the concentrations of Al, Ba, Cr, Cu, Fe, Mn, Pb, Sr and Zn. We found that the trace element contents of exuviae are a good proxy of the trace element contents of both the larvae and the adults. We conclude that exuvia is useful for assessing the environmental health of aquatic ecosystems. It is an environmentally friendly method and it can be used even in the case of protected dragonfly species.

Acute toxicity of four metals to three tropical aquatic invertebrates: The dragonfly Tramea cophysa and the ostracods Chlamydotheca sp. and Strandesia trispinosa

The relatively low availability of toxicity data for indigenous tropical species has often been discussed. In addition, several taxonomic groups of invertebrates are understudied, such as dragonflies and ostracods. The aim of the present study was therefore to evaluate the acute toxicity of four metals (cadmium - Cd, copper - Cu, manganese - Mn, and mercury - Hg) to the tropical dragonfly nymphs of Tramea cophysa and two tropical ostracod species (Chlamydotheca sp. and Strandesia trispinosa). Toxicity data for other invertebrates were also mined to allow comparing the sensitivity of the three test species with that of other (temperate and tropical) invertebrates. The order of metal sensitivity was different for the three test species: T. cophysa: Cu > CdHg > Mn, Chlamydotheca sp.: Cd > Cu > Hg > Mn, and S. trispinosa: Cd > Hg > Cu > Mn. However, manganese was the least toxic metal tested for all three species, which is hypothesized to be due to a possible metal transfer to the cuticle of the moulting test species. The sensitivity ranking of the three test species to the metals was S. trispinosa > Chlamydotheca sp.>T. cophysa (except for Cu for which the ranking was Chlamydotheca sp.>T. cophysa > S. trispinosa). Overall, the test species are concluded to be suitable test organisms for tropical toxicity evaluations. Future studies should also evaluate the chronic toxicity and include other important metal exposure routes such as sediment and food.

Crimean-Congo hemorrhagic fever (CCHF) seroprevalence: A systematic review and meta-analysis

Crimean-Congo haemorrhagic fever (CCHF) is the most widespread, tick-borne viral disease affecting humans and therefore this paper performed a meta-analysis to highlight seroprevalence features of CCHF in a global context. After a preliminary review of the 396 papers representing areas throughout the world, 206 were selected for detailed meta-analysis. In general the total means of CCHF seroprevalence were, respectively 4.7 and 24.6% for humans and animals; and 17.1, 18.9, 24.3, 29.3 and 27.1% for camels, cattle, goats, sheep and livestock. Statistical analysis revealed a significant difference in seroprevalence between humans and camels (P = 0.043), cattle (P = 0.010), goats (P = 0.015), sheep (P = 0.005) and livestock (P = 0.017). Regionally, there also was a difference between humans, and goats (P = 0.0001), sheep (P = 0.007) and livestock (P = 0.002). Globally, CCHF seroprevalence in at-risk professionals was 7.5 fold greater than in normal humans, while CCHF seroprevalence was 5 fold greater in animals, camels, cattle, goats, sheep and livestock than normal humans. Animal contact, animal husbandry, farming, tick bite history and secretion exposure were the most frequently reported CCHF seropositivity risk factors. This study serves as an important resource for epidemiological discussions related to CCHF and CCHF seroprevalence features, providing specific information in understanding human and animal mean and trend CCHF seroprevalence for different regions of the world and on an aggregate global scale; seroprevalence in at-risk professionals; and total mean and trend CCHF seropositivity involving risk factors.

Effect of seasonality on the population density of wetland aquatic insects: A case study of the Hawr Al Azim and Shadegan wetlands, Iran

Aim:

Wetlands are extremely suitable ecosystems to assess the effect of climate change on the density of aquatic insects. This study aimed to assess the effect of seasonality on populations of aquatic insects in the Hawr Al Azim and Shadegan wetlands.

Materials and Methods:

The insect samplings were conducted at a large area of the Hawr Al Azim and five different sites of the Shadegan wetlands. In total, 18,534 arthropods of different life stages, including 12 orders containing 51 families, were collected and identified from the selected sites of the Shadegan and Hawr Al Azim wetlands.

Results:

Results showed that the population density of wetland aquatic insects gradually increased as the average daily temperature decreased, positively increased with daily mean relative humidity and precipitation, and decreased with the mean daily evaporation between October and April. Conversely, the population density of wetland aquatic insects gradually decreased with increasing average daily temperature and reduction of the mean relative humidity and precipitation and increasing the average evaporation from April to September. When differences between the average daily and water temperatures reached minimum in April, the population density of wetland aquatic insects reached maximum and turned mainly to families that they have high level of biological indices, indicating that wetlands have clean waters around the spring. While around the autumn conversely, they mostly changed to families that they have low level of biological indices, indicating that wetlands have unclean waters.

Conclusion:

The present study showed an optimum condition for the growth of insects around spring. Seasonality affects the population density of wetland aquatic insects during a year.

From sea squirts to squirrelfish: facultative trace element hyperaccumulation in animals

The hyperaccumulation of trace elements is a widely characterized phenomenon in plants, bacteria, and fungi, but has received little attention in animals. However, there are numerous examples of animals that specifically and facultatively accumulate trace elements in the absence of elevated environmental concentrations. Metal hyperaccumulating animals are usually marine invertebrates, likely owing to environmental (e.g. constant exposure via the water) and physiological (e.g. osmoconforming and reduced integument permeability) factors. However, there are examples of terrestrial animals (insect larvae) and marine vertebrates (e.g. squirrelfish) that accumulate high body and/or tissue metal burdens. This review examines examples of animal hyperaccumulation of the elements arsenic, copper, iron, titanium, vanadium and zinc, describing mechanisms by which accumulation occurs and, where possible, hypothesizing functional roles. Groups such as the ascidians (sea squirts), molluscs (gastropods, bivalves and cephalopods) and polychaete annelids feature prominently as animals with hyperaccumulating capacity. Many of these species are potential model organisms offering insight into fundamental processes underlying metal handling, with relevance to human disease and aquatic metal toxicity, and some offer promise in applied fields such as bioremediation.