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Abstract Background The western districts of Mizoram (Lunglei, Mamit, and Lawngtlai) are malaria hotspots. Understanding the knowledge, attitude, and practices of the tribal communities in Mizoram’s western districts will aid the development of specific interventions. Methods An explanatory sequential mixed-method study was conducted from April to November 2023 in the Lunglei district. In a community-based cross-sectional survey of 353 participants, the knowledge, attitude, practices, and care-seeking behaviour toward malaria were assessed using a semi-structured questionnaire. Data was analysed using SPSS version 29 software; univariate variables were presented in percentage, and bivariate and multivariate variables were analysed using the chi-square test and logistic regression, respectively. This was followed by in-depth telephonic interviews of twelve participants, and the data was analysed using NVivo. Results Out of the 353 respondents, 77.9%, 82.7%, 55.5%, and 63.2% of the participants had good knowledge, attitude, practices, and care-seeking behaviour, respectively. The in-depth qualitative interviews highlighted the villagers’ good knowledge of the various aspects of malaria transmission, treatment, and prevention practices (indoor residual spraying and use of insecticide-treated nets). Conclusion High disease endemicity, awareness programmes and vector control interventions might be contributing to the overall good knowledge, attitude, and practices toward malaria among the villagers. In addition to vector control measures, active parasite surveillance is key to malaria control in this region.

Photorhabdus and Xenorhabdus are the bacterial symbionts of insect pathogenic nematodes, Heterorhabditis and Steinernema, respectively. This study aims to characterize the bacterial symbionts from Mizoram, North-east India and to evaluate their antibacterial potential. The bacterial isolates were characterized using recA and gyrB gene regions. The ethyl acetate extract of bacterial isolates was tested against pathogenic bacterial strains, viz. Escherichia coli (ATCC 10536), Klebsiella pneumoniae (ATCC 10031), Pseudomonas aeruginosa (ATCC 10145), and Bacillus subtilis (ATCC 11774) using disk diffusion method. Analysis of recA and gyrB genes revealed that the Photorhabdus isolates were P. hindustanensis, and P. namnaonensis. This study constitutes the first documentation of P. namnaonensis from India. The two isolated Xenorhabdus belong to X. vietnamensis and X. stockiae. The ethyl acetate extracts of the studied bacteria suppressed the development of all the microorganisms tested. Based on MIC and MBC values, the highest activity was exhibited by TS (P. hindustanensis) and TD (P. namnaonensis) isolates against P. aeruginosa and K. pneumoniae respectively. The lowest inhibitory activity was observed on both Xenorhabdus isolates (RF and PTS) against B. subtilis. This study focuses on the existence and identification of symbiotic bacteria from Mizoram, an Indo-Burma biodiversity hotspot region, and details their activity against different pathogenic bacteria. Since these metabolites could be potent antibiotics, further research is required to better understand the genetic information, chemical composition, and method of action against other microorganisms.

BackgroundIn the past decade, scrub typhus cases have been reported across India, even in regions that had no previous history of the disease. In the North-East Indian state of Mizoram, scrub typhus cases were first recorded only in 2012. However, in the last five years, the state has seen a substantial increase in the scrub typhus and other rickettsial infections. As part of the public health response, the Mizoram Government has integrated screening and line listing of scrub typhus and other rickettsial infections across all its health settings, a first in India. Here we detail the epidemiology of scrub typhus and other rickettsial infections from 2018-2022, systematically recorded across the state of Mizoram.Methodology/principal findingsThe line-listed data positive for scrub typhus and other rickettsial infections identified by rapid immunochromatographic test and/or Weil-Felix test from 2018-22 was used for the analysis. During this period, 22,914 cases of rickettsial infections were recorded, out of which 19,651 were scrub typhus cases. Aizawl is the worst affected, with 10,580 cases (46.17%). The average incidence of rickettsial infections is 3.54 cases per 1000 persons-year, and the case fatality rate is 0.35. Only ∼2% of the reported scrub typhus cases had eschar. Multivariate logistic regression analysis indicate patients with eschar (aOR = 2.5, pConclusionThe integration of systematic surveillance and recording of rickettsial diseases across Mizoram has shed important insights into their prevalence, morbidity, and mortality. This study underscores the importance of active surveillance of rickettsial infections across India, as the burden could be substantially higher, and is probably going undetected.

Abstract Background Outbreak of the fall armyworm Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) occurred in Mizoram, North-Eastern India. The infestation spread in the entire state covering a total area of around 2840 hectares of maize cultivated land. Entomopathogenic nematodes (EPNs) represent potential candidates for the biological control of S. frugiperda. In the study, the susceptibility of the pest against 4 locally isolated EPN species Heterorhabditis indica, H. baujardi, Steinernema sangi and S. surkhetense was evaluated. Results The results indicated that all the isolated EPN species showed a high rate of larvicidal and pupicidal activities against the pest. Mortality between 43.75–100.00 and 25.00–100.00% of 3rd and 5th larval instars, respectively (at concentrations 10–800 IJs/larva), and 37.50–68.75% mortality of pupae (at concentrations 200–1600 IJs /pupa) were found after exposure to the EPN species. The mortality rate of the pest showed significant variations with life stages of the host insect, nematode concentrations and incubation time. Based on the median lethal concentration (LC50), H. indica was the most pathogenic species, followed by S. sangi, H. baujardi and S. surkhetense. The LC50 values of H. indica at 72 h post-incubation were 20.26 and 62.07 IJs/larva for the 3rd and 5th larval instars, respectively, and 913.34 IJs/pupa. The penetration assay showed that H. indica had the highest penetration rate into the hosts, 27.24, 21.30 and 20.00% in the 3rd, 5th larval instars and pupae, respectively. Furthermore, all the EPN isolates were capable of successful multiplication inside the cadaver of S. frugiperda that showed significant differences with the EPN isolates and life stages of the pest. Among the isolates, H. indica showed the highest multiplication rates, 17,692.25 ± 2103.59, 8345.63 ± 785.34 and 79,146.38 ± 5943.73 IJs per 3rd instar larva, 5th instar larva and pupa, respectively. Conclusions The study revealed that the 4 species of EPNs showed a high potency against S. frugiperda, thereby having the potential to be developed as a biological control agent against the pest. Moreover, the isolated EPN species could potentially serve as alternatives for chemical insecticides and could further be incorporated into the Integrated Pest Management (IPM).

Photorhabdus and Xenorhabdus are the bacterial symbionts of insect pathogenic nematodes, Heterorhabditis and Steinernema, respectively. This study aims to characterize the bacterial symbionts from Mizoram, North-east India and to evaluate their antibacterial potential. The bacterial isolates were characterized using recA and gyrB gene regions. The ethyl acetate extract of bacterial isolates was tested against pathogenic bacterial strains, viz. Escherichia coli (ATCC 10536), Klebsiella pneumoniae (ATCC 10031), Pseudomonas aeruginosa (ATCC 10145), and Bacillus subtilis (ATCC 11774) using disk diffusion method. Analysis of recA and gyrB genes revealed that the Photorhabdus isolates were P. hindustanensis, and P. namnaonensis. This study constitutes the first documentation of P. namnaonensis from India. The two isolated Xenorhabdus belong to X. vietnamensis and X. stockiae. The ethyl acetate extracts of the studied bacteria suppressed the development of all the microorganisms tested. Based on MIC and MBC values, the highest activity was exhibited by TS (P. hindustanensis) and TD (P. namnaonensis) isolates against P. aeruginosa and K. pneumoniae respectively. The lowest inhibitory activity was observed on both Xenorhabdus isolates (RF and PTS) against B. subtilis. This study focuses on the existence and identification of symbiotic bacteria from Mizoram, an Indo-Burma biodiversity hotspot region, and details their activity against different pathogenic bacteria. Since these metabolites could be potent antibiotics, further research is required to better understand the genetic information, chemical composition, and method of action against other microorganisms. [ABSTRACT FROM AUTHOR]

In the last decade, scrub typhus, a zoonotic disease has emerged as a major health concern in Mizoram, a North‐East Indian state that shares international borders with Myanmar and Bangladesh. Mizoram is a biodiversity hotspot and >85% of the state is under forest cover, which provides an ideal ecological niche for the rodents and mites to transmit scrub typhus and other rickettsial infections. Using the Weil‐Felix test, a serosurvey of household rodents from 41 villages spread across all the 11 districts in Mizoram was undertaken to gather important insights on their role in disease transmission. Furthermore, the chigger and flea indexes were calculated from the captured rodents. The 163 rodents captured belonged to five species; the highest numbers were from Rattus tanezumi (87), followed by Rattus rattus (41), Mus musculus (17), Suncus murinus (16), and Bandicota bengalensis (2). The rickettsial seropositivity of the captured rodents was 66.26% (108 out of 163 were positive). Among the 163 rodents, sera of 75 (46.01%), 61 (37.42%), and 73 (44.78%) were reactive to OXK, OX19, and OX2 antigens, respectively. The chigger and flea index were 17.92 and 0.16, respectively. Overall, the study has given important insights into the risk of multiple rickettsial infections that household rodents could transmit in Mizoram. These findings indicate the need for the urgent implementation of effective rodent control strategies in Mizoram. [ABSTRACT FROM AUTHOR]

Scrub typhus, which is one of the rickettsial diseases, is an acute, febrile illness in men caused by the pathogen, 18 a gram-negative bacterium Orientia tsutsugamushi from the bite of infected mite. Outbreaks of scrub typhus have been reported from various parts of North, South, and Eastern India. There was a report of two unfortunate death cases from Cheural village due to scrub typhus at Lawngtlai district hospital. While, multiple cases, having symptoms like scrub typhus illness were also reported by health officials of the residents of Cheural village, Lawngtlai District, Mizoram. Among the 242 person tested, 80 (33.05%) person were found reactive with Weil felix PROGEN OXK at 1:160 titre value. Maximum numbers of cases were observed among the working age group 20-60 years. Among the different occupational groups, farmers were the most affected as more than 90% of the villagers were involved in forest farming. The five captured rodents' sera were also tested with Weil felix. All of the captured rodent sera were reactive with one or more antigen. Mites (chigger) were also collected from the rodent samples and the chigger index was found to be 19.2. This study indicated that scrub typhus and other rickettsial diseases were responsible for the outbreak. The extremely high chigger index with reactivity rate reactivity rate of Weil felix with sera of captured rodents strongly indicated the household transmission of scrub typhus and other rickettsial diseases in the outbreak village. [ABSTRACT FROM AUTHOR]

The complete mitochondrial genome of Himalayan beeApis laboriosa, from Mizoram, India, has been sequenced using Illumina NextSeq500 platform and analysed. The mitogenome was assembled and found to be 15 266 bp in length and the gene arrangement is similar to other honey bee species. TheA. laboriosamitogenome comprises of 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs and an A + T-rich region of 346 bp. Based on the concatenated PCGs, in the phylogenetic tree,A. laboriosais placed as a sister group along with the cavity nesting honey bees. The present study reports the first complete mitochondrial genome sequence ofA. laboriosa, which will enhance our knowledge on Apinae mitogenomes and phylogeny. [ABSTRACT FROM AUTHOR]

Most studies on the diversity of amphibians in northeast India were based on classical morpho-taxonomy, which have a high probability of errors in species identification. DNA barcoding of amphibians using the mitochondrial 16S rRNA gene has been used successfully for the identification of species and detection of cryptic species. In the present study, we carry out DNA barcoding of two rhacophorid species of the genus Raorchestes and Kurixalus that are not readily identifiable to the species level based on their morphology. Our analysis on the 16S rRNA gene revealed that these species were Raorchestes cangyuanensis and Kurixalus yangi, species which were recorded for the first time and second time from India respectively. We discuss on the records of R. longchuanensis from Bangladesh and India, which were based on the misidentification of R. cangyuanensis. We therefore propose to delist this species from the faunal list of Bangladesh and India. We further raise a question as to why the population of Kurixalus from Motuo, Xizang province of China was assigned as K. naso and not the population described as K. yangi, which is morphologically similar to K. naso and is also recorded from a locality close to the type locality of K. naso.

Stoliczka (1870) described Hylorana nicobariensis from the Nicobar Islands of India. The generic allocation of this enigmatic species is yet to be fully resolved (Chan et al. 2020b) and it has been placed in different genera (Boulenger 1885; Frost et al. 2006; Che et al. 2007; Oliver et al. 2015; Chan et al. 2020a; Chandramouli et al. 2020). As of now, the species is assigned to the genus Indosylvirana (Oliver et al. 2015; Chan et al. 2020b; Frost 2020). Apart from Nicobar archipelago, this species is distributed in the insular regions of southeast Asia (Oliver et al. 2015; Chandramouli et al. 2020; Frost 2020) and the states of Arunachal Pradesh, Assam, Mizoram, Tripura and West Bengal in northeast India (Sarkar et al. 1992, 2002; Sarkar Ray 2006; Ahmed et al. 2009; Mathew Sen 2010; Lalremsanga 2011; Lalremsanga et al. 2015, 2016). However, Frost (2020) doubted the records of this species in northeast India. Systematic studies on the herpetofauna of northeast India based on molecular evidence are scanty (Lalronunga et al. 2020a), and species recorded from the area need confirmation (Frost 2020). Recent studies revealed that many species previously recorded from northeast India were based on misidentifications (Das et al. 2019; Giri et al. 2019; Lalronunga et al. 2020b), therefore, a review and revalidation on the herpetofaunal list of the area is warranted. Herein, we examined the identity of the species recorded as I. nicobariensis from northeast India using morphological data and a fragment of 16S rRNA mitochondrial gene.

We provide the first molecular phylogenetic data for the following poorly known Northeast Indian snakes: Blythia reticulata and B. hmuifang, Hebius xenura, and Trachischium spp. Based on 1071 bp of cytb, 578 bp of nd4, 509 bp of 16s, 1000 bp of rag1 and 672 bp of cmos, we found support for a monophyletic Blythia being a member of Natricinae, most closely related to Trachischium. Hebius xenura is recovered as nested within species of the recently resurrected genus Herpetoreas, to which we transfer it.

Physoschistura chhimtuipuiensis, new species, from a tributary of the Kaladan River in Mizoram, northeastern India, is distinguished from all other species of Physoschistura by a combination of the following characters: scales between pectoral- and pelvic-fin bases deeply embedded and sparsely set, lateral line incomplete with 56-63 pores, reaching slightly beyond the base of the last anal-fin ray, a suborbital flap in male, 8½ branched dorsal-fin rays and 8+7 branched caudal-fin rays.