Though asymptomatic plasmodial infection (API) is well known phenomenon and play an important role in different populations and malaria transmission settings, it has received less attention in malaria intervention strategies. This review was aimed to estimate the prevalence of API in pregnant women across the world. The bibliography records relevant to the study were searched on PubMed and Lilacs, till August 15, 2016, without restriction of language. A total of 78 references were identified, of which 29 met the inclusion criteria. The study of the identified reports revealed that the mean prevalence of API in pregnant women was 10.8% (3382/31186), with wide variation among countries and transmission settings. The reports showed that APIs are very common even in low malaria transmission areas, and most of the APIs are due to submicroscopic plasmodial infection (SPI). More sensitive diagnostic tools are required to address API and SPI in such areas. Every malaria endemic region/country should carry out systematic studies for accurate estimation of frequency for both these events (API and SPI) in different populations for planning appropriate intervention measures.

Background & objectives: An increase in Zika virus (ZIKV) epidemic during the last decade has become a major global concern as the virus affects both newborns and adult humans. Earlier studies have shown the impact of ZIKV infection in developing human foetus. However, effective in vitro model of target cells for studying the ZIKV infection in adult human neurons is not available. This study aimed to establish the use of human neuroblastoma cell line (SH-SY5Y) for studying an infection of ZIKV in vitro. Methods: ZIKV growth kinetics, viral toxicity, and SH-SY5Y cell vialibity were determined after ZIKV infection in SH-SY5Y cells in vitro. ZIKV-infected SH-SY5Y cells were morphologically analysed and compared with nonhuman primate Vero cells. Furthermore, the susceptibility of SH-SY5Y cells to ZIKV infection was also determined. Results: The results showed that ZIKV efficiently infects SH-SY5Y cell lines in vitro. Gradual changes of several cellular homeostasis parameters including cell viability, cytotoxicity, and cell morphology were observed in ZIKV-infected SH-SY5Y cells when compared to mock-treated or non-human primate cells. Interestingly, ZIKV particles were detected in the nucleoplasmic compartment of the infected SH-SY5Y cells. Interpretation & conclusion: The results suggest that ZIKV particle can be detected in the nucleoplasmic compartment of the infected SH-SY5Y cells beside the known viral replicating cytoplasmic area. Hence, SH-SY5Y cells can be used as an in vitro adult human neuronal cell-based model, for further elucidating the ZIKV biology, and highlight other possible significance of Zika virus distribution through nuclear localization, which may correlate to the neuropathological defects in ZIKV-infected adult humans.

Background & objectives: Malaria is a deadly parasitic disease, having a high rate of incidence and mortality across the world. The spread and development of resistance against chemical insecticides is one of the major problems associated with malaria treatment and control. Hence, plant based formulations may serve as an alternative source towards development of new drugs for treatment of malaria. The present study was aimed to evaluate the in vitro antiplasmodial activities of leaf, stem and flower of Calotropis gigantea against chloroquine-sensitive Plasmodium falciparum (3D7 strain) and its cytotoxicity against THP-1 cell lines. The plant extract which showed highest potency, in the in vitro antimalarial activity was further tested in vivo against P. berghei (ANKA strain) for validating its efficacy. Methods: The crude extracts of methanol, ethyl acetate and chloroform from leaves, stem and flowers of C. gigantea were prepared using Soxhlet apparatus. These extracts were screened for in vitro antimalarial activity against P. falciparum 3D7 strain. The cytotoxicity studies of crude extracts were conducted against THP-1 cell line. Phytochemical analysis of these extracts was carried out by following the standard methods. The damage to erythrocytes due to the plant extracts was tested. The in vivo study was conducted in P. berghei (ANKA) infected BALB/c albino mice by following the 4-day suppressive test. Results: The phytochemical screening of the crude extracts showed the presence of alkaloids, flavonoids, triter-penes, tannins, carbohydrates, phenols, coumarins, saponins, phlobatannins and steroids. Out of all the extracts, the methanolic extract of leaves showed highest antimalarial activity with IC₅₀ value of 12.17 μg/ml. In cytotoxicity evaluation, none of the crude extracts, showed cytotoxicity on THP-1 cell line. Since, methanolic leaf extract of C. gigantea showed good antimalarial activity in vitro, it was tested in vivo. In the in vivo results, the methanolic leaf extract of C. gigantea exhibited an excellent activity against P. berghei malaria parasite, wherein the decrement of parasite counts was moderately low and dose-dependent (p < 0.05) in comparison to the P. berghei infected control group, which showed a daily increase of parasitaemia unlike the chloroquine-treated group. Interpretation & conclusion: The methanolic leaf extract of C. gigantea may act as potent alternative source for development of new medicines or drugs for the treatment of drug-resistant malaria. Thus, further research is needed to characterize the bioactive molecules of the extracts of C. gigantea that are responsible for inhibition of malaria parasite.

Background & objectives: Increase in prevalence and intensity of insecticide-resistance in vectors of vector-borne diseases is a major threat to sustainable disease control; and, for their effective management, studies on resistance mechanisms are important to come out with suitable strategies. Esterases are major class of detoxification enzymes in mosquitoes, which confers protection against insecticides in causing resistance. This study was aimed at biochemical characterization of esterases responsible for malathion resistance in Anopheles stephensi mosquitoes, along with its validation through biochemical techniques and native-PAGE assays. Methods: Laboratory maintained susceptible and resistant An. stephensi mosquitoes were used for assessing the activity and effect of α- and β-esterases on malathion. Bioassay, synergist bioassay, biochemical assay and native- PAGE were employed to characterize the role of esterases in conferring malathion-resistance. Results: Notably significant (p < 0.0001) enhancement in α- and β-esterases activity was observed with 2-fold increase in resistant An. stephensi_GOA compared to susceptible An. stephensi_BB native-PAGE depicted two major bands ‘a’ (R_f = 0.80) and ‘b’ (R_f = 0.72) in susceptible An. stephensi_BB while one intense band ‘b’ (R_f = 0.72) was visible in resistant An. stephensi_GOA. Inhibition assay revealed complete inhibition of α- and β-esterases activity in presence of 1 mM malathion in susceptible strain compared to observed partial inhibition in resistant strain on native-PAGE. Interpretation & conclusion: This study provides a better understanding on the role of esterase enzyme (carboxylesterase) in conferring malathion-resistance in An. stephensi mosquitoes, as evident from the native-PAGE assay results. The study results could be used in characterizing the resistance mechanisms in vectors and for suggesting alternative chemical insecticide based resistance management strategies for effective vector-borne disease control.

Background & objectives: Cutaneous leishmaniasis displays two epidemiological routes of transmission, zoonotic cutaneous leishmaniasis (ZCL) which includes animal reservoir hosts in the transmission cycle and anthroponotic cutaneous leishmaniasis (ACL), where human is the sole source of infection for the vector sandflies. About 10–13% of CL cases are reported each year from Adana province in Turkey. The aim of this study was to develop a predictive model for determining the spatial risk level of cutaneous leishmaniasis in the Adana province, southern part of Turkey, in relation to environmental factors. Methods: Entomological survey was carried out between June 2015 and September 2016. Sandflies were collected from Karaisali district of the Adana province using light-traps and sticky papers. Sandfly fauna results were compared with environmental data obtained from field-survey, and examined with univariate and binary logistic regression in PASW statistical software. The ArcMap application of ArcGIS10.0. software was used for geographical adjustments to create maps and establish a risk model. Results: In total five sandfly species were identified in the study area, and three of them (Phlebotomus tobbi, P. neglectus/syriacus and P. perfiliewi) were detected as potential vectors of cutaneous leishmaniasis. The results showed that enhanced vegetation index (EVI) and emissivity band 31 (EMIS31) values are related to the distribution of these three species. Interpretation & conclusion: The created risk maps may provide useful information to guide the control programme interventions and prevent the economic loses in the future insecticide applications. They could be used to better understand the distribution of vectors, and determine the epidemiology and risk level of the CL.

Background & objectives: Despite a tremendous expansion in the financing and coverage of malaria control programmes, the disease continues to be a global health threat. This study was conducted to assess the entomological parameters of anopheline mosquitoes, viz. species composition, abundance, longevity, behaviour and infectivity rates in Kersa district, Jimma zone, southwestern Ethiopia. Methods: Mosquito collection was carried out from each selected household in each of the nine selected study villages of Kersa district, using CDC light-traps and pyrethrum spray catches (PSCs) for seven months (June to December 2014). Mosquito count data were log transformed before analysis and the data were analyzed using SPSS software package version 16.0. Analysis of variance (ANOVA) was employed to compare means and Tukey’s post-hoc test was used for mean separation. Results: In total, 1559 adult female anopheline mosquitoes, representing at least three species were collected from the study villages. Of these, 1122 were collected by CDC light-traps and the rest 437 were collected by PSCs. Anopheles gambiae s.l. (71.8%) was the most abundant species, followed by An. coustani s.l. (22%) and An. pharoensis (6.2%). The mean monthly density of anopheline mosquito species was highly significant (p < 0.001). Significantly (p <0.05) higher population of An. gambiae s.l. were trapped indoor than outdoor. However, outdoor mean densities ofAn. pharoensis and An. coustani s.l. were significantly (p < 0.001) higher than indoor mean densities. The longevity of An. gambiae s.l. was higher in the months of June, July and August (mean 7.32 days) and lower in the months of October, November and December (mean 2.94 days). Two An. gambiae s.l. specimens were found positive for Plasmodium vivax 210 polymorphs and the overall infectivity rate was estimated to be 1.04%. Interpretation & conclusion: This study could contribute to the understanding of anopheline mosquitoes with respect to their composition, dynamics, distribution and behaviour in Kersa district, for evidence based malaria vector control programmes, mainly in the appropriate timing of the indoor residual spray programme.

Background & objectives: Prevention of malaria in pregnancy is a key intervention for reducing maternal mortality and morbidity in the tropical region of Africa. The present study was aimed to determine whether the administration of two doses of intermittent preventive treatment (IPT) with sulphadoxine-pyrimethamine (IPT-SP) and use of insecticide treated nets (ITNs) is correlated with reduced incidence of malaria in pregnancy or not. Methods: In total 270 pregnant women were randomly divided into three groups; A, B and C depending on the use of IPT and ITN, and were tested for malaria in pregnancy. Results: The overall prevalence of malaria parasitaemia was found to be 57.8%. The prevalence rate was 56.7% for group A (IPT alone); 45.6% for group B (IPT and ITN) and 71.1% for group C (None). The difference between group A and C was statistically significant (χ² = 4.07, OR = 1.88,p < 0.04). Also, women in group A were one and half times more susceptible to malaria than women in group B (χ² = 2.22, OR = 1.56,p < 0.14). Interpretation & conclusion: The use of IPT-SP and ITN was found to be significantly associated with reduced malarial infestation during pregnancy in the study area. There is a need to scale up both the strategies in order to reduce the high burden of malaria in pregnant women.

Background & objectives: Dengue fever, caused by dengue virus (DENV), has become a serious threat to human lives. Phytochemicals are known to have great potential to eradicate viral, bacterial and fungal-borne diseases in human beings. This study was aimed at in silico drug development against nonstructural protein 4B (NS4B) of dengue virus 4 (DENV4). Methods: A total of 2750 phytochemicals from different medicinal plants were selected for this study. These plants grow naturally in the climate of Pakistan and India and have been used for the treatment of various pathologies in human for long-time. The ADMET studies, molecular docking and density functional theory (DFT) based analysis were carried out to determine the potential inhibitory properties of these phytochemicals. Results: The ADMET analysis and docking results revealed nine phytochemicals, i.e. Silymarin, Flavobion, Derrisin, Isosilybin, Mundulinol, Silydianin, Isopomiferin, Narlumicine and Oxysanguinarine to have potential inhibitory properties against DENV and can be considered for additional in vitro and in vivo studies to assess their inhibitory effects against DENV replication. They exhibited binding affinity ≥−8 kcal/mol against DENV4-NS4B. Furthermore, DFT based analysis revealed high reactivity for these nine phytochemicals in the binding pocket of DENV4-NS4B, based on E_LUMO, E_HOMO and band energy gap. Interpretation & conclusion: Five out of nine phytochemicals are reported for the first time as novel DENV inhibitors. These included three phytochemicals from Silybum marianum, i.e. Derrisin, Mundulinol, Isopomiferin, and two phytochemicals from Fumaria indica, i.e. Narlumicine and Oxysanguinarine. However, all the nine phytochemicals can be considered for in vitro and in vivo analysis for the development of potential DENV inhibitors.

Background & objectives: The Far-North region of Cameroon has been considered free of tsetse and trypanosomiasis for the past three decades. But recent reports by pastoralists indicate its reappearance in the region. This study was aimed to confirm the existence of cattle trypanosomiasis and determine its prevalence, and to establish pastoralists knowledge and practice (KP) of the disease in Ndiyam Shinwa pastoral zone of Cameroon. Methods: A total of 118 herds were surveyed for a descriptive, cross-sectional study in Ndiyam Shinwa pastoral zone from May to November 2014. Out of these, 110 herds were visited in the beginning of the rainy season, 22 of the 110 herds (suspect cattle) were revisited along with the remaining eight herds in the end of the season. The blood samples of 635 suspect cattle and 135 nonsuspect cattle were collected. Samples were subjected to two diagnostic tests: Buffy coat test (BCT) and packed cell volume (PCV) determination. A survey on pastoralist’s (n = 118) KP about trypanosomiasis was also undertaken. Results: Parasitological analyses revealed six infections by Trypanosoma vivax: Four in suspect cattle against two in nonsuspect cattle, corresponding respectively to apparent prevalence of 0.63 and 1.46% and true prevalence of (0.79–3.15%) and (1.82–7.30%). The proportion of cattle found infected in the PCV as well as BCT tests was 33.26% for suspect cattle. More than 75% of followed-up suspects showed persisting symptoms nearly three months after initial examination. The most common diagnostic signs for pastoralists were ruffled hair, lacrimation, anorexia and emaciation. Interpretation & conclusion: Cattle trypanosomiasis has reappeared in the Far-North region and seems to be in the inter-epizootic phase. Pastoralists have a good knowledge of the disease, but their perception of its importance seems to be influenced by the persistence of symptoms attributed to this disease in suspect cattle.

Background & objectives: Japanese encephalitis (JE) is one of the most common causes of acute encephalitis syndrome in many states of India. Uttar Pradesh state is well known for JE endemicity, contributing 75% of total cases during recent past. Several sporadic cases have been reported from Bareilly region of the state. The disease spread by bite of Culex mosquito. Survey of literature revealed no data on mosquito fauna with reference to JE in this region. Therefore, this study was planned to survey seasonal mosquito population and occurrence of JE vectors in Bareilly region. Methods: Mosquitoes were sampled on monthly basis from organized pig farm from February 2016 to January 2017 and identified using mosquito identification keys. The meteorological parameters of the area were obtained monthly and standard statistical methods were used to assess the relationship between different weather variables and mosquito population. Results: A total of 4337 mosquitoes belonging to five genera were collected. Mosquitoes of genus Culex were predominant and contributed 84.41% to the total catch. The most dominant species was Cx. tritaeniorhynchus (30.81%), followed by Cx. quinquefasciatus (28.50%), Cx. gelidus (17.24%), Cx. pseudovishnui (11.85%), Cx. vishnui (8.11%), Cx. fuscocephala (2.70%), Cx. infula (0.76%) and Cx. bitaeniorhynchus (0.03%). Pronounced seasonal variation was observed with majority of mosquitoes showing high density in monsoon and post-monsoon period. Interpretation & conclusion: The present study provides knowledge on distribution of JE vector in Bareilly which indicates that the area is at risk of JE outbreak. Abundance of Culex vector clearly demarcates possible threat of JE incidence in the study area. A long-term entomological study is needed to further evaluate the significant role of different weather variables in shaping mosquito densities.

Background & objectives: Babesia is an intraerythrocytic protozoan parasite which is transmitted by hard ticks of the Ixodidae family. One of the problems associated with protozoan infection is the determination and characterization of the vectors. The aim of the present study was to detect Babesia ovis in the salivary gland of Dermacentor spp. Methods: A total of 200 adult Dermacentor ticks (139 D. niveus and 61 D. marginatus) were collected from sheep suspected to be infected with babesiosis in the Ardabil region of Iran from April to September 2015 (active season of ticks); and were identified using standard taxonomic keys. Deoxyribonucleic acid (DNA) was isolated from the salivary glands of ticks and analyzed with the primers derived from the hyper variable V4 region of 18S ribosomal ribonucleic acid (18S rRNA) of the Babesia species using polymerase chain reaction (PCR). Results: Babesia ovis was detected in 5.8% of the D. niveus and 3.3% of the D. marginatus positive samples in the second round of semi-nested PCR. Interpretation & conclusion: Based on the results obtained from this study, it is concluded that D. niveus and D. marginatus, which are distributed in Ardabil region of Iran, might play a major role in the transmission of infection as a natural vector of B. ovis.

Background & objectives: Phlebotomine sandflies (Diptera: Psychodidae) transmit several important zoonotic diseases to humans and leishmaniasis is one of them. Two types of leishmaniasis, viz. visceral leishmaniasis (VL) and cutaneous leishmaniasis (CL) are endemic in Iran. The main vector of anthroponotic cutaneous leishmaniasis (ACL) is Phlebotomus sergenti. The aim of the present study was to determine the susceptibility status of wild strain of P. sergenti to different imagicides of DDT, bendiocarb and permethrin at the median lethal time, LT₅₀ level. Methods: Sandflies were collected from selected village in North Khorasan Province, northeast of Iran from indoors using CDC light-traps. Susceptibility test was carried out against DDT (4%), bendiocarb (0.1%) and permethrin (0.75%) for all the females according to WHO method, and mortality was calculated. Species identification was carried out using the morphological keys. Data were analysed using probit regression analysis to determine the LT₅₀ and LT₉₀ values. Results: In total, 851 female P. sergenti sandflies were tested. LT₅₀ values to DDT (4%), Bendiocarb (0.1%) and permethrin (0.75%) were 15.4, 19.2 and 6.3 min respectively. The values for LT₉₀ were 51.1, 47.4 and 18.6 min respectively. The mortality rates for 1 h exposure time to DDT, bendiocarb and permethrin were 89.8 ± 1.4; 93.6 ± 1.4; and 95.6 ± 1.7%, respectively. Interpretation & conclusion: The suscesptibility studies revealed development of resistance against DDT (4%) in the wild strain of P. sergenti population. Monitoring and mapping of insecticide resistance in the region is recommended for vector control.