Dengue is the most important mosquito-borne viral infection of humans. Although outbreaks of disease which are now recognized as clinically consistent with dengue have been reported for centuries, it was not until half a century ago that laboratory identification of dengue viruses as the etiological agent of febrile illness was achieved. This debilitating and sometimes fatal disease is widely distributed in >125 countries in tropical and subtropical zones of the world. Asia, South America and the Pacific Islands are hyper-epidemic regions while currently there is less prevalence in Europe, North America and Australia. The estimated global incidence ranges between 200 and 400 million clinical cases per year. While some areas of past epidemics are now considered to be under control, recent decades have witnessed an epidemic rise in dengue worldwide. Major factors facilitating expansion include climate change and increase in urbanization and international travel. Concurrently, the non-availability of an efficacious antiviral drug or vaccine and a lack of effective vector control strategies collectively make dengue a serious public health concern. Thus, it is of paramount importance to analyze the history of the spread of infection and to gain a deeper understanding of patterns of transmission in order to anticipate epidemiological trends more accurately, thereby enabling better preparedness for future outbreaks.

Zika virus infection is an emerging mosquito-borne disease, first identified in Uganda in 1947. It is caused by the Zika arbovirus, and transmitted by the bites of infected mosquitoes of the genus Aedes. For almost half a century, the Zika virus was reported as the causative agent of sporadic human infections. In 2007, the Zika virus emerged outside Asia and Africa causing an epidemic on the Island of Yap in Micronesia. The manifestation of the newly acquired human infection varies from asymptomatic to self-limiting acute febrile illness with symptoms and clinical features similar to those caused by the Dengue virus ('Dengue-like syndrome'). The real-time PCR and serological methods have been successfully applied for the diagnosis of the disease. The treatment is symptomatic, since there is no specific antiviral treatment or a vaccine. During the recent outbreaks in French Polynesia and Brazil, incidents of Guillain-Barrι syndrome and microcephaly were associated with Zika virus infection, giving rise to fears of further global spread of the virus. Prevention and vector control strategies have to be urgently implemented by national health authorities in order to contain future outbreaks in vulnerable populations. This review summarizes the existing information on Zika virus characteristics, pathogenesis and epidemiology, the available methods for the diagnosis of Zika virus infection and recent approaches for prevention and control.

Background & objectives: Despite continuous global attempts to fight parasitic infections, malaria still remains one of the major human life threatening diseases. Difficulty of producing efficient antimalaria vaccines and increasing drug-resistant strains, highlight the urgent need to search for a new alternative antimalaria drug. The aim of this study was to find a new agent against malaria parasite with maximum efficacy and minimum range of side-effects. For this, the antiplasmodial activity of commercial chitosan, a natural carbohydrate polymer, was evaluated on Plasmodium berghei via in vivo experiments. This is the first report that to highlight antimalarial effects of low molecular weight chitosan against P. berghei in vivo. Methods: Low molecular weight chitosan with 95% degree of deacetylation was melted in normal saline with 1% (w/v) acetic acid for preparing 10, 20, 40 and 80 mg/kg concentrations of chitosan, which were then examined for their antimalarial efficacy in P. berghei infected mice. Results: The study showed that differrent concentrations of chitosan exhibited significant antimalarial effect (p= 0.002) when compared with the control group. Also, analysis of mice survival time showed significant differences between 20 and 80 mg/kg concentrations of used chitosan in comparison to negative control group. Interpretation & conclusion: The results of this study showed that the chitosan has potent antimalarial activity and could be suggested as an alternative antimalarial drug component.

Background & objectives: Phlebotomine sandflies lose their legs after exposure to pyrethroids. In some insects leg loss helps to defend them from intoxication and predation, a phenomenon known as autotomy. A field observation has shown that sandflies that have lost some legs are still able to blood-feed. The aims of the study were to determine whether leg loss in sandflies, after exposure to deltamethrin, is due to autotomy and to establish the effect of the leg loss on blood-feeding. Methods: Two experiments were carried out with Lutzomyia longipalpis: (i) Females were individually exposed to a sublethal time of deltamethrin and mortality and the number of leg loss were recorded; and (ii) Groups of females with complete legs or with 1-3 legs lost due to pyrethroid exposure were offered a blood meal and percentages of blood-fed and fully-fed females were recorded. Results: Most females lost a median of 1 leg within 1-48 h post-exposure to deltamethrin. Mortality (after 24 h) was significantly higher for exposed females with lost legs (31.1%), compared to exposed females with complete legs (7.3%), and there were no differences in mortality between females with complete legs and the control (unexposed females). There were no differences between the three treatments in the percentages of blood-fed and fully-fed females. Interpretation & conclusion: Leg loss in sandflies is a toxic effect of pyrethroids and there was no evidence of autotomy. The loss of up to three legs after exposure to pyrethroids does not affect blood-feeding behaviour in laboratory and probably also in wild conditions.

Background & objectives: The Ramgarh district of Jharkhand state, India is highly malarious owing to abundance of different malaria vector species, namely Anopheles culicifacies, An. fluviatilis and An. annularis. In spite of high prevalence of malaria vectors in Ramgarh, their larval ecology and climatic conditions affecting malaria dynamics have never been studied. Therefore, the objective of this study was to identify the diversity of potential breeding habitats and breeding preferences of anopheline vectors in the Ramgarh district. Methods: Anopheles immature collection was carried out at potential aquatic habitats in Ramgarh and Gola sites using the standard dipper on fortnightly basis from August 2012 to July 2013. The immatures were reared till adult emergence and further identified using standard keys. Temperature of outdoor and water bodies was recorded through temperature data loggers, and rainfall through standard rain gauges installed at each site. Results: A total of 6495 immature specimens representing 17 Anopheles species including three malaria vectors, viz. An. culicifacies, An. fluviatilis and An. annularis were collected from 11 types of breeding habitats. The highly preferred breeding habitats of vector anophelines were river bed pools, rivulets, wells, ponds, river margins, ditches and irrigation channels. Larval abundance of vector species showed site-specific variation with temperature and rainfall patterns throughout the year. The Shannon-Weiner diversity index ranged from 0.19 to 1.94 at Ramgarh site and 0.16 to 1.76 at Gola site. Interpretation & conclusion: The study revealed that malaria vector species have been adapted to breed in a wide range of water bodies. The regular monitoring of such specific vector breeding sites under changing ecological and environmental conditions will be useful in guiding larval control operations selectively for effective vector/ malaria control.

Background & objectives: Phlebotomus papatasi is the main vector of the zoonotic cutaneous leishmaniasis (ZCL) in Qom Province and many other provinces of Iran. Attractive toxic sugar baits (ATSB) treated barrier fence is one of the new methods for controlling the vectors such as sandflies. The present study was designed to evaluate the residual activity of ATSB-treated barrier fence that was used in control of P. papatasi. Methods: Following the selection of villages in Markazi district of Qom Province, central Iran during 2015 for ATSB and ASB (bait containing no active ingredient) methods; barrier fences on the ground in front of the rodent's colony were installed. A total of four conical tubes were installed and fixed on surfaces of treated barrier net of dimension 25 Χ 25 cm at biweekly interval. In each conical tube, 10 sand flies were released and after 3 min of exposure they were transferred to sterile cups. After 24 h, the obtained results were recorded according to the survival and mortality rate of sandflies. These tests were carried out five days after the installation of barrier fences, and repeated every 15 days until the mortality rate decreased to 60-65%. Results: The bioassay tests results showed that the mortality rate of P. papatasi on ATSB-treated barrier fence for 5, 15, 30 and 45 days after spraying was 100, 95.83, 88.18 and 66.67% respectively, which decreased to 50.83% after 60 days. Interpretation & conclusion: Persistence and residual activity of the active ingredient of the bait in the hot and dry climatic conditions of Qom Province remained significantly effective for at most 45 days, which subsequently decreased at a high rate. Hence, every 45 days barrier fences need to be impregnated with ATSB bait. The method also appeared cost-effective and could be practical in implementation of vector control programmes against ZCL.

Background & objectives: Antimalarial drug resistance is a serious challenge to malaria control worldwide. In vitro sensitivity assays provide an early indication of emerging drug resistance. In vitro susceptibility of field and culture adapted Plasmodium falciparum isolates to different antimalarials was compared using two Methods: World Health Organization (WHO) micro-test (MARK III) and histidine rich protein II (HRP II) based enzyme- linked immunosorbent assay (ELISA). Methods: In total, 50 P. falciparum isolates were collected from five states, viz. Chhattisgarh, Meghalaya, Mizoram, Tripura and Odisha of India during December 2011-September 2014. The isolates were revived and evaluated for their susceptibility to chloroquine (CQ), monodesethylamodiaquine (AQ), mefloquine (MQ), quinine (QN) and artemisinin (ART) using the WHO micro-test (Mark III) and HRP II ELISA. The data were analyzed using non- linear regression analysis. Results: The geometric mean (GM) IC50 values of different antimalarials for WHO Mark III assay were comparatively lower than HRP II ELISA assay. The GM IC50 value for CQ was 59.5 nM (95% confidence interval [CI]: 49.35-71.73 nM) and 78.34 nM (95% CI: 64.57-95.03 nM) for Mark III and HRP II ELISA, respectively. Similarly, the values of GM IC50 for AQ, MQ, QN and ART by Mark III and HRP II ELISA were 13.31, 7.07, 146.4, 0.43 nM and 22.02, 11.46, 258.7, 1.00 nM, respectively. On analyzing statistically, the results of both assays were comparable (R2 = 0.96, p < 0.001; mean log difference at IC50= 0.037). Interpretation & conclusion: The HRP II ELISA assay showed a reliable sensitivity in comparison to WHO Mark III micro-test complemented with distinguishing features such as high specificity, ease of performance, and notable consistency.

Background & objectives: Lyme borreliosis is the most common tick-borne disease in Europe and the USA. However, a great variety of pathogens are transmitted by ticks, which results in mixed infections, with Lyme borreliosis. The aim of the present study was to show the incidence of Borrelia burgdorferi, Anaplasma phagocytophilum, and Babesia microti coinfections among the population of foresters and farmers, as these people, due to their profession, are particularly exposed to tick contact. Methods: The study was carried out in eastern Poland (the northern part of the Lublin Province) in 2013. The study was performed in a group of 93 individuals occupationally exposed to tick bites (foresters and farmers), whose blood serum showed the presence of IgG anti-B. burgdorferi antibodies. Blood serum in this group were evaluated for IgG anti-A. phagocytophilum and IgG anti-B. microti antibodies by means of IFA IgG indirect immunofluorescence tests. Information related to age, sex, number of tick bite episodes, presence of various symptoms related to the tick bites, and antibiotic therapy applied as treatment for diagnosed Lyme borreliosis were obtained from the subjects through a structured questionnaire. The results were analyzed in Statistica v. 7.1 statistical analysis software. Results: The presence of IgG antibodies against the analyzed pathogens revealed B. burgdorferi and A. phagocytophilum coinfection in 26 (28%) of the examined subjects and B. burgdorferi and B. microti coinfection in one person (1.1%). No coinfection with all the three pathogens was observed in any individual. The co-occurrence of headache plus bone, joint and muscle pain was noted significantly more often among individuals diagnosed with B. burgdorferi and A. phagocytophilum coinfection. Interpretation & conclusion: Foresters and farmers are exposed to B. burgdorferi and A. phagocytophilum coinfection in the study area. Therefore, it is probable that these pathogens may severely interfere with the clinical course of Lyme borreliosis.

Background & objectives: Many etiological agents of zoonoses are considered as significant biological hazard to people visiting forested areas frequently, for instance, hunters. They may be exposed to ticks, rodents, and birds as well as excreta/secretions of wild animals or contaminated water and soil. Hence, this population is at risk of contracting infection with pathogens such as Borrelia burgdorferi sensu lato (s.l.), Anaplasma phagocytophilum, Babesia spp., tick-borne encephalitis virus, Bartonella spp., Francisella tularensis, Echinococcus spp., or hantaviruses. The aim of the study was to assess the seroprevalence of zoonotic agents, viz. A. phagocytophilum, hantaviruses, and Echinococcus spp., with special regard to B. burgdorferi s.l., among hunters in Lubelskie Voivodeship (eastern Poland). Methods: Serum samples collected from 134 hunters from Lubelskie Voivodeship were analyzed with the use of immunological techniques (enzyme-linked immunosorbent assay, line immunoblot test, and indirect fluorescence assay) for the presence of antibodies against the agents. Results: Specific antibodies were detected in 66% of the tested individuals. Antibodies against B. burgdorferi s.l. (39%), A. phagocytophilum (30%), hantaviruses (9%), and Echinococcus spp. (8%) were detected individually or as mixed results. Interpretation & conclusion: The results confirm that there is a risk of exposure to different pathogens in the forested areas in eastern Poland and that hunters are highly vulnerable to infection with the examined zoonotic agents. A significant proportion of co-occurring antibodies against different pathogens was noticed. Thus, hunters have to take special care of their health status evaluation and mitigate the exposure risk by using adequate prophylaxis measures.

Background & objectives: Leishmaniasis is caused by protozoa of Leishmania genus and is considered as a zoonotic disease. It is a major public health problem worldwide, with high endemicity in developing countries like Iran. Various chemical drugs are used for leishmaniasis treatment, but their side-effects and the emergence of drug resistance have led to look for new effective compounds. The aim of this study was to introduce purslane (Portulaca oleracea) as a traditional and medicinal herb which might act as a valuable source for designing new pharmaceutical drug/lead against Leishmania sp. Methods: This study was conducted in the laboratory of Seddigheh Tahereh Infectious Disease Research Center, Isfahan, Iran during the spring of 2015. The essence from the purslane plant was prepared through water distillation and the alcoholic extract was prepared through maceration method. The essence was dried, and diluted with DMSO (5%). Leishmania major promastigotes were cultured in 25 ΁ 2΀C temperature in the stationary phase of RPMI-1640 medium, enriched with 10% fetal calf serum and penicillin-streptomycin to yield higher quantity. The biological activity of herb essence was evaluated on L. major promastigotes and compared to glucantime reference drug using methylthiazole tetrazolium (MTT) colorometric assay. The optical density absorbance was measured with Eliza reader set, and the IC50 value was calculated at different time intervals. All tests were repeated thrice. Results were analyzed by using Tukey test and t-test. Results: The IC50 values after 48 h, for glucantime against standard parasite promastigotes and clinical strains were equal to 12 and 19 mg/ml, respectively, whereas for purslane herb leaves and stems essence; it was equal to 360 and 680 mg/ml, respectively. Although, the glucantime pharmaceutical drug was more efficient compared to the investigated herb essence, the essense had significant effect on L. major promastigotes with increasing density (p <0.05). The ingredients of the herb leaves and stem essence were-Phytol, squalene, palmitic acid, ethyl- linoleate, ferulic acid, linolenic acid, scopoletin, linoleic acid, rhein, apigenin, and bergapten. Interpretation & conclusion: The study showed that essence of purslane has considerable antileishmanial effects and can stop the growth of parasites in the laboratory compared to glucantime. More experiments are necessary to investigate its effect on Leishmania parasite in animal model.

Background & objectives: The mechanism of antimony resistance in Leishmania has been studied extensively, in connection with decreased influx and/or increased eflux of the drug. Aquaporin 1 (AQP1) protein has been shown to mediate the uptake of trivalent antimony. This study was aimed to find the expression level of AQP1 gene in resistant versus non-resistant clinical isolates of Leishmania major in Iranian patients. Methods: Clinical isolates were obtained from 16 considered patients referred to Navab Safavi Clinical Center, Isfahan, Iran from October 2014 to December 2015. After diagnosis of cutaneous leishmaniasis using microscopic observation, biopsy was performed from lesion(s) of each patient and stored inside RNAlater solution at -20΀C. Written informed consent was obtained from all the patients to participate in the study before recording their information and sampling based on Helsinki declaration. Each patient was treated with Glucantime and followed for three months. All sensitive and resistance isolates were considered and compared with AQP1 gene expression using real time PCR that was analyzed with delta-delta Ct. Results: Out of 16 clinical isolates, four patients were resistant and 12 were non-resistant. The AQP1 gene expression in resistant isolates was significantly higher than the one in response failure isolates (p = 0.001). Interpretation & conclusion: The significant over expression (0.5 fold) of AQP1 gene in resistant versus non- resistant isolates suggests different mechanism of drug resistance such as mutations. Mutations may change the physiological function of the Aquaporin 1 protein that might affect its expression level.