Physicochemical characteristics of larval habitats and biodiversity of mosquitoes in one of the most important metropolises of southern Iran.

The present study aimed to investigate the roles of the physicochemical characteristics of larval habitats in biodiversity and other bionomic factors of mosquitoes in Shiraz. The physical parameters of all habitats were recorded separately. The collected mosquito larvae were identified based on morphological characters. The water samples of larval habitats were analyzed for Biochemical Oxygen Demand (BOD, mg/L), Chemical Oxygen Demand (COD, mg/L), pH, alkalinity, turbidity, total hardness (mg/L), Electrical Conductivity (EC, µS/cm), Total Dissolved Solids (TDS, mg/L), Cl2 (mg/L), and water temperature (°C). In addition, three main indices were used for surveying biodiversity. A total of 1229 larvae were collected from April to September 2018 and May to August 2019. Seven medically important mosquito species were identified morphologically. Culex quinquefasciatus and Cx. laticinctus had the highest distribution and abundance. Ecological results showed that the richness and diversity of species were higher and more stable in natural sites than in manmade places. The optimum BOD, COD, alkalinity, TDS, EC, pH, and temperature of water for mosquitoes of the studied areas were 140 mg/L, 360 mg/L, 160 mg/L, 420 mg/L, 840 µS/cm, 8.3, and 24 °C, respectively. Most mosquitoes tended to live in manmade, temporary, and sunny larval habitats with turbid water. The results provided a better understanding of the biology and ecology of mosquitoes as the most important group of disease vectors to humans and animals. Hence, they could be used to apply some safer and more environmentally friendly methods for mosquito control.

First molecular detection of SARS-CoV-2 virus in cockroaches.

Coronavirus is one of the main pathogens that primarily targets the human respiratory system. There are several ways to transmit this virus, such as direct contact or droplets spread by coughing or sneezing, and direct contact with fomites and surfaces is another way. This cross-sectional study was conducted in Shiraz, southern Iran, in 2021. 5 locations, including 3 hospitals and 2 dormitories, were selected for the survey. The cockroaches were collected from selected locations and transferred to the Laboratory of Medical Entomology at Shiraz University of Medical Sciences. All specimens were identified morphologically. The external and gastrointestinal washouts of collected samples with sterile phosphate-buffered saline separately were used for molecular analysis. An RT-qPCR assay, which suggests the possible insect­borne transmission, was used. External and gastrointestinal washout of B. germanica from Dastgheyb Dormitory and P. americana from Ali-Asghar Hospital were positive for contamination with the SARS-CoV-2. Cockroaches spread the virus in the environment and contaminate human food and various surfaces of buildings. Their role will be more important in crowded places such as hotels, lodging houses, restaurants, and hospitals; vector control programs should be carried out with more accuracy in such places.

New Record of Spiders (Arachnida: Araneae) from Bashagard District, Southern Iran, with the Report of a Medically Important Species.

Spiders are the largest order of arachnids with some medically important species. Considering that no comprehensive research has been conducted on the fauna and distribution of Araneae in Bashagard County (Hormozgan Province) so far, the present investigation has been carried out on these essential issues in this deprived tropical region. Fifteen sampling locations were selected based on the extent of each area and considering climatic characteristics. Samplings were carried out at least four times in each region from February 2017 to September 2018, covering up to a radius of 500 meters from the defined locations. Specimens were collected using the hand collection method, pitfall trapping, and aspirator sampling. All collected samples were preserved in 70% ethanol and were identified using valid taxonomic keys. Of all the 390 collected samples, 134 identifiable specimens were considered for morphological identification. 11 species belonging to 10 genera and seven families were identified. Immature specimens were identified only at the family level. Wadicosa fidelis was the most distributed and abundant species in the area, with 13 localities and 84.33% of all identifiable samples. Plexippus minor is a new record for the spider fauna of Iran. Moreover, Loxosceles rufescens, a medically important species, Artema doriae, and Eusparassus mesopotamicus were reported for the first time from Hormozgan province. Despite collecting only one specimen, of L. rufescens, due to the lack of proper medical facilities and transportation systems in the area, health staff must be alert about this medically important species and warn residents about its potential dangers.

First molecular-based detection of SARS-CoV-2 virus in the field-collected houseflies.

This is the first report of SARS-CoV-2 detection on field-collected Musca domestica housefly surface and tissue samples using the high-sensitive PCR assay which suggests the possible insect-borne transmission. The study was conducted in Shiraz city, southern Iran, in May and Jun 2020. Adult flies were sampled at the outdoor areas of two hospitals treating COVID-19 patients. Fly samples were first washed twice to remove the insect surface attached to SARS-CoV-2 virions. After that, the disinfected fly samples were homogenized. Fly surface washout and homogenate samples were tested using Taq Man real-time PCR assay for the SARS-CoV-2 virus. In a total of 156 houseflies, 75% of samples from the body washout samples were positive for SARS-CoV-2. Strikingly, 37% of the homogenized specimens were positive for the SARS-CoV-2, suggesting the possible infection of the insects or uptake of the virion to the insect metabolism. The other possibility is the houseflies up took the blood or blood fluids of the patients and the RNA of the SARS-CoV-2 survived in the insect body without replicating. Our preliminary findings suggest that the houseflies could transmit SARS-CoV-2 as a mechanical or biological vector especially during the warm seasons while increasing the population and activity of houseflies.