Mapping current and future risk of scorpion sting from a species with low medical concern, Mesobuthus phillipsii (Scorpiones: Buthidae) in Iran.

Scorpion stings are one of the most important health challenges and high priority research topic in public health. In this study, we aimed to model habitat suitability of the Mesobuthus phillipsii (Pocock 1889), a species with low medical concern, under current and future climatic conditions in Iran. We also identified vulnerable populations to scorpion stings in the country. Scorpion sting risk modeling was done using an ensemble approach by considering two species distribution modeling methods: MaxEnt and Random Forest methods. Distribution modeling was performed using the sdm R package. The results showed that due to climate change in 2070, the high-risk areas will increase from 20,839 to 79,212 km2. Habitats with a moderate risk of scorpion stings will also increase from 139,347 to 222,833 km2. Consequently, the number of villages in high-risk areas of scorpion stings will increase from 2,870 to 7,017, while this number will increase from 12,759 to 20,104 in the case of medium-risk villages. The results of this study can be used for scorpion stings management in Iran. This study can be used as an example for similar studies on scorpions with high medical emergency.

Susceptibility of Culiseta longiareolata to insecticides in West Azerbaijan province, northwestern Iran.

Mosquitoes are involved in the transmission of a wide range of diseases and among them, Culiseta longiareolata, acts as a vector of avian malaria, tularemia and several arboviruses like West Nile fever. The current study was conducted to determine the susceptibility of C. longiareolata against deltamethrin 0.05% (pyrethroids), fenitrothion 1.00% (organophosphate) and bendiocarb 0.10% (carbamate). Mosquitoes were collected from different parts of Urmia county, the capital of West Azerbaijan. In the current study, 443 empty 3 - 5 days old adult female C. longiareolata were used for susceptibility tests. The susceptibility status of C. longiareolata was determined using WHO's recommended procedure. The results indicated higher mortality rates of Culiseta longiareolata against studied insecticides. Culiseta longiareolata, was resistant to all studied insecticides (deltamethrin, mortality rate: 62.50%, fenitrothion, mortality rate: 35.96% and bendiocarb, mortality rate: 20.16%). The current study represents the first report of susceptibility status of C. longiareolata to fenitrothion and bendicarb in Iran. Considering the climatic diversity and geographical conditions of northwestern Iran, reports of resistance of other mosquitoes' of this region, the susceptibility status of medically and veterinary important mosquitoes should be given serious attention.

Molecular Characterisation of Cytochrome Oxidase I and Internal Transcribed Spacer 2 Fragments of Culiseta longiareolata.

Objective: Among the mosquitoes, Culiseta longiareolata plays a notable role in the transmission of avian malaria, tularemia and arboviral diseases, including West Nile fever. We conducted this study to characterise the cytochrome oxidase I (COI) and internal transcribed spacer 2 (ITS2) fragments of Cs. longiareolata in northwestern Iran to determine the classification status of this species. Methods: The COI and ITS2 fragments from six populations of Cs. longiareolata were amplified, sequenced and analysed. For phylogenetic analysis, the evolutionary history was estimated using the Tamura-Nei-based Maximum Likelihood approach. Results: Thirteen sequences (six for ITS2 and seven for COI) from six populations of Cs. longiareolata were acquired and deposited into the GenBank. Phylogenetic analysis showed that the COI sequences from the current study cluster together with the same species from other parts of the world. Moreover, the ITS2 sequences of the current study and sequences retrieved from the GenBank, despite intraspecies variation, fall into a distinct clade with acceptable bootstrap values. Conclusion: Notable genetic variations were observed between various Cs. longiareolata populations based on the evaluations of ITS2 and COI fragments. By conducting such studies, the exact classification status of this species can be determined.

Molecular characterization of Ribosomal DNA (ITS2) of hard ticks in Iran: understanding the conspecificity of Dermacentor marginatus and D. niveus.

OBJECTIVES: Hard ticks (Acari: Ixodidae) are ectoparasites of medical and veterinary importance. They are obligate blood-feeding vectors with the ability to transmit a wide variety of pathogens. Standard morphological keys are normally used for the identification of tick species. However, considering the importance of accurate species identification and the determination of bio-ecological characteristics of species, relying on morphological keys alone can be questionable. In this study, two DNA fragments (ITS2 and COI) were selected for phylogenetic evaluation of Iranian hard tick species belonging to the genera Dermacentor, Hyalomma, and Rhipicephalus. RESULTS: 1229 specimens of Dermacentor marginatus, D. niveus, Hyalomma anatolicum, Rhipicephalus bursa, and R. sanguineus s.l constituting 11 populations were collected from three different climatic and zoogeographical zones in Iran. Morphological studies revealed notable differences in important morphological characteristics between different populations of D. marginatus. The results of ITS2 sequence analysis provided additional evidence which supports the conspecificity of D. niveus and D. marginatus. Contrary to this finding, the sequence analysis of COI and phylogeny favored the separation of the two species. Given the greater importance of COI in identifying and discriminating species, a possibility heterospecificity between the two species should be considered.

Experimental Study on Plasmodium berghei, Anopheles Stephensi, and BALB/c Mouse System: Implications for Malaria Transmission Blocking Assays.

BACKGROUND: Plasmodium berghei is a rodent malaria parasite and has been very valuable means in the progress of our understanding of the essential molecular and cellular biology of the malaria parasites. Availability of hosts such as mice and vectors such as Anopheles stephensi has made this parasite a suitable system to study the parasite-host and vector-parasite relationships. METHODS: This study was performed at Medical Entomology and Parasitology laboratories of the School of Public Health, Tehran University of Medical Sciences, Iran in 2016. The investigation was carried out to describe life cycle and parameters influencing maintenance of the parasite within the mice or the mosquito. RESULTS: Results have revealed details and addressed some parameters and points influence maintenance of various life stages of the parasite including merozoites, macrogametocytes, ookinetes, oocysts and sporozoites in the laboratory model P. berghei-A. stephensi-BALB/c mouse. Injection of fresh infected blood results in higher gametocytemia in the animals. The more injected parasites result in earlier and higher parasitemia and exfelagellation centers in the mice blood. However, the highest number of infected mosquitoes and oocysts formation were observed when the parasitemia and exflagellation centers per microscopic field were 9% and 3.6 in the infected mice respectively. The infected mosquitoes should be maintained on 8% (w/v) fructose, 0.05% (w/v) PABA at 20±1 °C and 50%-80% relative humidity. CONCLUSION: This study helps to understand the biology of vertebrate-parasite and mosquito-malaria interactions that may aid in the development of a new generation of drug/vaccine and vector-based measures for malaria control.

West Nile Virus in Mosquitoes of Iranian Wetlands.

The West Nile virus (WNV) transmission cycle includes a wide range of migratory wetland birds as reservoirs, mosquitoes as biological vectors, and equines and humans as dead-end hosts. Despite the presence of potential vector species, there is no information about the existence of WNV in mosquito vectors in Iran. The Iranian West Azerbaijan Province is located in the northwestern part of Iran and has borders with Turkey, Iraq, Armenia, and the Republic of Azerbaijan. The current study was conducted to identify the wetland mosquitoes of the West Azerbaijan Province and their infection with WNV. In this study, 2143 specimens were collected, comprising 1541 adults and 602 larvae. Six species belonging to four genera were collected and identified: Anopheles maculipennis sensu lato (s.l.), Culex (Cx.) hortensis, Cx. pipiens s.l., Cx. theileri, Culiseta longiareolata, and Aedes (Ae.) (Ochlerotatus) caspius. In total, 45 pools of mosquitoes were examined. Two of the adult pools collected from the same location showed the presence of WNV in Ae. (Och.) caspius, from Sangar, Makoo County, as confirmed by PCR and sequencing. Due to the discovery of WNV in the mosquito population of the region, and the presence of wetlands and significant populations of migratory birds, the health sector should carefully monitor the factors involved in the cycle of this disease.

Assessing the Fauna of Aquatic Insects for Possible Use for Malaria Vector Control in Large River, Central Iran.

Insects with over 30,000 aquatic species are known as very successful arthropods in freshwater habitats. Some of them are applied as biological indicators for water quality control, as well as the main food supply for fishes and amphibians. The faunistic studies are the basic step in entomological researches; the current study was carried out emphasizing on the fauna of aquatic insects in Karaj River, northern Iran. A field study was carried out in six various sampling site of Karaj River during spring 2013. The aquatic insects were collected using several methods such as D-frame nets, dipping and direct search on river floor stones. Specimens were collected and preserved in Ethanol and identified by standard identification keys. Totally, 211 samples were collected belonging to three orders; Plecoptera, Trichoptera and Ephemeroptera. Seven genuses (Perla, Isoperla, Hydropsyche, Cheumatopsyche, Baetis, Heptagenia and Maccafferium) from five families (Perlidae, Perlodidae, Hydropsychidae, Batidae, Heptagenidae) were identified. The most predominant order was Plecoptera followed by Trichoptera. Karaj River is a main and important river, which provides almost all of water of Karaj dam. So, identification of aquatic species which exist in this river is vital and further studies about systematic and ecological investigations should be performed. Also, monitoring of aquatic biota by trained health personnel can be a critical step to describe water quality in this river. Understanding the fauna of aquatic insects will provide a clue for possible biological control of medically important aquatic insects such as Anopheles as the malaria vectors.

Comparative susceptibility of different biological forms of Anopheles stephensi to Plasmodium berghei ANKA strain.

BACKGROUND: There are varying degrees of compatibility between malaria parasite-mosquito species, and understanding this compatibility may be crucial for developing effective transmission-blocking vaccines. This study investigates the compatibility of different biological forms of a malaria vector, Anopheles stephensi, to Plasmodium berghei ANKA strain. METHODS: Several biologically different and allopatric forms of A. stephensi were studied. Three forms were isolated from different regions of southern Iran: the variety mysorensis, the intermediate form and the native type form, and an additional type form originated from India (Beech strain).The mosquitoes were experimentally infected with P. berghei to compare their susceptibility to parasitism. Anti-mosquito midgut antiserum was then raised in BALB/cs mice immunized against gut antigens from the most susceptible form of A. stephensi (Beech strain), and the efficacy of the antiserum was assessed in transmission-blocking assays conducted on the least susceptible mosquito biological form. RESULTS: The susceptibility of different biological forms of A. stephensi mosquito to P. berghei was specifically inter-type varied. The Beech strain and the intermediate form were both highly susceptible to infection, with higher oocyst and sporozoite infection rates than intermediate and mysorensis forms. The oocyst infection, and particularly sporozite infection, was lowest in the mysorensis strain. Antiserum raised against midgut proteins of the Indian Beech type form blocked infection in this mosquito population, but it was ineffective at blocking both oocyst and sporozoite development in the permissive but geographically distant intermediate form mosquitoes. This suggests that a strong degree of incompatibility exists between the mosquito strains in terms of midgut protein(s) acting as putative ookinete receptors. CONCLUSIONS: The incompatibility in the midgut protein profiles between two biological forms of A. stephensi demonstrates a well-differentiated population structure according to geographical origin. Therefore, the design of potential transmission-blocking strategies should incorporate a more thorough understanding of intra-species variations in host-parasite interactions.