Journal of Arthropod-Borne Diseases最新文献

Background: Head lice infestation is known as a serious health problem in developing and developed countries. The prevalence of pediculosis in children and females is higher than others. The infestation may cause the absence of student from school and make their parents upset. The aim of current study was to evaluate the WHO recommended insecticides for control of head lice in Islamshahr health center.

Methods: In the current study infested individuals were older than 6 years old and have been diagnosed with at least 3 head lice adult and 10 live nits from less than 0.7 cm scalp. The pediculicides was applied randomly among groups. Permethrin shampoo as a golden standard was used. Dimethicone lotion 4% and Ivermectin lotion was compared with it. This study was conducted on 179 infested people. Results of infestation were evaluated after one month of intervention. Different indicators such as: present of head lice adult or live nit, redness and irritation in head skin were invested.

Results: All the participants were female and 72.6% of them were in the age group of 6-11. The result revealed that aging not only decreases the infection rate but also raised the recovery percentage. The results showed that 79.5% permethrin receiver, 83% of people who treated with Dimethicone lotion and 90.6% of Ivermectin receiver had no head lice. There was no significant difference among these three pediculicides.

Conclusion: There was no significant difference among tested pediculicides. An appropriate pediculicide can be selected by training people.

Background: Cockroaches are one of the most common pests in many residential areas. In this study, the simultaneous effects of fungi, Metarhizium anisopliae and fenitrothion-coated baits on the mortality rate of the German cockroach nymphs were investigated.

Methods: To determine the lethal level of fenitrothion insecticide, a bioassay test was performed on the last instar nymphs of the German cockroach reared at insectarium conditions. Various toxic concentrations of fenitrothion (0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1.5%, and 2%) were used. Different concentrations of M. anisopliae (1×10⁴, 1×10⁵, 1×10⁶, 1×10⁷, 1×10⁸ Conidia/ml) were also applied to nymphs. Eventually, we combined the effective dose of fenitrothion (0.93%) with the effective concentration of M. anisopliae (6.6 ×10⁶ Conidia/ml) to provide the fungus-coated bait to attract insects. Mortality was recorded 24-96 hours after exposure to the toxic bait. The resulting data were subjected to Probit analysis.

Results: The results of applying M. anisopliae spores with fenitrothion composition showed that the mortality rate of German cockroach nymphs was significant. Therefore, the optimal dose of fenitrothion used in combination with M. anisopliae seems essential to reduce the German cockroach nymphs.

Conclusion: The results of this study can be considered a suitable method as a mixture with low cost and minimal damage to the environment and other organisms.

Cutaneous leishmaniasis is a neglected and parasitic vector borne diseases that is endemic in tropical and subtropical countries, including Iran. The aim of this study was to explain the present status of CL in Iran. This report is based on data that recorded by cutaneous leishmaniasis surveillance system in 2019, and evaluated in Center for Communicable Diseases Management in Ministry of Health in Iran. Iran has been considered an endemic area for cutaneous leishmaniasis in the world. Dependent to activities for cutaneous leishmaniasis control the number of cases decreased from 23202 in 2008 (Incidence rate 32 per 100000) to 13124 in 2019 (Incidence rate 15.8 per 100000), more cases reported from September to December, in 2019, 46% of cases had one lesion and 21% had 2 lesions, 85% of cases diagnosed when the diameter of lesions had 3 centimeters and bellows. Although the Leishmania control program began in 1977, the incidence of the disease has dropped dramatically since 2008 when the new cutaneous leishmaniasis control program have been implemented. Although in some areas the incidence of the disease increased, but the implementation of the new program has reduced the number of cases, in order to continue reducing the disease, permanent support for the control programs is needed.

Background: Any mosquito control methods requires precise information about population dynamics, variety, biology and mosquito habitat. This research assessed Culicid mosquitoes' attraction to a human host and a calf to better understand their behavior.

Methods: Adult mosquitoes were sampled in 22 weeks in southwestern Iran's Nur Ali Village from May to October 2015. The mosquitoes were drawn to the person and calf as bait, while the unbaited trap was also used. A substantial statistical difference between attracted mosquitoes to the hosts was determined in the T-test.

Results: Within 22 weeks, 29821 mosquitoes were captured. Only 9% were collected from the human baited net trap, 89.1% from the calf baited net trap, and 1.9% from the unbaited net trap. The number of collected female mosquitoes was statistically significantly higher using the calf baited net trap of the total mosquitoes, 916 were randomly identified at the species level by local identification keys. Of these, 63 were Anopheles stephensi (human: 16%, calf: 75% and unbaited: 9%), 83 An. pulcherrimus (human: 27%, calf: 60% and unbaited: 13%), 118 Aedes caspius (human: 24%, calf: 69% and unbaited: 7%), 493 Culex tritaeniorhynchus (human: 52%, calf: 37% and unbaited: 11%), 153 Cx. quinquefasciatus (human: 44%, calf: 47% and unbaited: 9%), and 6 Cx. theileri (human: 33%, calf: 50% and unbaited: 17%).

Conclusion: The obtained results here provide useful insights into the mosquito population and the possibility of using this information as an essential part of integrated vector management regarding the reemergence of malaria or other mosquito-borne.

Background: Phlebotomus papatasi is known as the main vector of zoonotic cutaneous leishmaniasis. This study aimed to investigate the effect of geographical and bioclimatic factors on the Ph. papatasi distribution.

Methods: A total of 34 villages were selected, and sampling was performed three times using 120 sticky traps in each selected village. All the collected species were mounted and identified their species. The densities of Ph. papatasi were measured in all the villages and entered into ArcMap as a point layer. The required bioclimatic and environmental variables were extracted from the global climate database and The normalized difference vegetation index was obtained from the MODIS satellite imagery, also, all variables entered into ArcMap as raster layers, so The numerical value of each independent variable in the cell where the selected village is located in this, was extracted using spatial analyst tools and the value to point submenu. All the data were finally entered into IBM SPSS, and the relationship was examined between the number of collected Ph. papatasi and the independent variables using Spearman's correlation test.

Results: A total of 1773 specimens of Ph. papatasi were collected. The findings of this study showed that max temperature of warmest month, temperature annual range, temperature seasonality, mean diurnal range, precipitation seasonality, mean temperature of driest and warmest quarter were positively associated with the density of Ph. papatasi.

Conclusion: Air temperature and precipitation were shown as the most significant factors in the distribution of Ph. papatasi.

Background: Ticks are forced vertebrate ectoparasites, including humans, and are vectors of serious diseases such as Crimean Congo Hemorrhagic Fever, Relapsing Fever, and various forms of encephalitis. Spatial assessment of the prevalence of ticks and detection of high risk areas for tick-borne disease transmission and evaluation of ecological measures are key aims of this research.

Methods: Ticks were collected using standard methods from 27 villages in the region of Sarab County in north-eastern Iran during the four seasons of 2018-2019 and identified using valid keys. The calculations of indices for biodiversity were based on the Margalef index, Shannon-Weiner index and Simpson index. R2.15 Statistical software was used for statistical analysis of indices of biodiversity, and ArcMap10.4.1 software, IDW and GeneralG methods were used. Analysis were used to investigate spatial distribution and to determine important tick hotspots.

Results: A total of 2500 animals surveyed, 35% of them were infected. In total, 1416 ticks were caught, 74.6 %, 23.9% and 1.4 % were adult, nymph and larvae respectively. 94% of the ticks were hard ticks including 6 genera. According to the Margalef diversity index, the highest species biodiversity was related to summer (1.4234), and the lowest was related to winter (0.7379).

Conclusion: Large hotspot area was found in the central part of the study area. The area of study was very prone to tick-borne disease transmission in terms of tick diversity and tick species richness. Tick-borne disease control is an important measure.

Background: This study was performed to evaluate in vitro and in vivo Leishmanicidal potential of morphine (Mph), imiquimod (IQ), and their combination.

Methods: Leishmania infantum promastigote and amastigote assays were performed at the presence of 0.015-150μM Mph, 0.04-416μM IQ, and their combination. The inhibition effects of these drugs on promastigotes were evaluated after 24, 48, and 72h. The cytotoxic effects of the drugs were evaluated by MTT as well as flow cytometry after 72h. We explored the therapeutic effects of Mph and IQ in BALB/c mice at the end of the treatment using parasite load determination and cytokine assay. One group of mice received Mph for three weeks before infection.

Results: The results of promastigote and amastigote assays showed the cytotoxic effects of the drugs at low concentrations. The cytotoxic effects were higher on promastigotes than amastigotes (p< 0.05). There was a negative correlation between drug concentration and amastigote/promastigote viability. Imiquimod alone or combined with Mph showed remarkable cytotoxic effects at all concentrations (p< 0.05). Flow cytometry results revealed apoptosis in the parasite following exposure to the drug combinations. Accordingly, the reduction of parasite loads in the spleen and liver was observed (p< 0.05) with simultaneous increases in IFN-γ and IL-4. We believe that the in vivo leishmanicidal effect was mediated by Mph through IL-4 and by IQ through both IL-4 and IFN-γ.

Conclusion: Results pointed out the promising effects of Mph and IQ at low concentrations, especially when combined.

Background: Seasonal activity patterns of mosquitoes are essential as baseline knowledge to understand the transmission dynamics of vector-borne diseases. This study was conducted to evaluate the monthly dynamics of the mosquito populations and their relation to meteorological factors in Mazandaran Province, north of Iran.

Methods: Mosquito adults and larvae were collected from 16 counties of Mazandaran Province using different sampling techniques, once a month from May to December 2014. "Index of Species Abundance" (ISA) along with "Standardized ISA" (SISA) was used for assessing the most abundant species of mosquitoes based on the explanations of Robert and Hsi. Pearson's correlation coefficient (R) was used to assess the relationships between the monthly population fluctuations and meteorological variables.

Results: Overall, 23750 mosquitoes belonging to four genera and nineteen species were collected and identified. The highest population density of mosquitoes was in July and the lowest in May. The ISA/SISA indices for Culex pipiens were both 1 for larvae and 1.25/0.973 for adults in total catch performed in human dwellings. For Cx. tritaeniorhynchus, the ISA/SISA were 1.68/0.938 in pit shelter method. A significant positive correlation was observed between population fluctuations of Cx. tritaeniorhynchus and mean temperature (R: 0.766, P< 0.027).

Conclusion: The results indicated that the mosquitoes are more active in July, and Cx. pipiens and Cx. tritaeniorhynchus were the most abundant species. Considering the potential of these species as vectors of numerous pathogens, control programs can be planed based on their monthly activity pattern in the area.