Transactions of The Royal Society of Tropical Medicine and Hygiene最新文献

Background: Globally, diarrhoeagenic Escherichia coli (DEC) has been implicated in the spread of waterborne diseases and abattoir wastewater has played a role in its dissemination into watersheds. This study isolated and characterised DEC from the abattoir wastewater-impacted Iyi-Etu River and other water sources at the Amansea livestock market settlement.

Methods: A total of 96 water samples comprising river water (upstream, downstream 1, downstream 2), borehole, well, sachet and abattoir wastewater samples were tested for DEC. In the inoculation process, membrane filtration was used, and selective media such as Eosin Methylene Blue, Chromoselect agar and Sorbitol Maconkey agar were used to screen for E. coli and Shiga toxin-producing E. coli (STEC) O157. Escherichia coli pathotypes were characterised using molecular techniques.

Results: Overall, E. coli was presumptively detected in 28.1% (27/96) of all samples. Of the 27 isolates, three (11.1%) were non-sorbitol fermenters (typical of E. coli O157), while 20 (74.1%) were confirmed as E. coli based on uidA housekeeping gene positivity. The detected circulating pathotypes were enteropathogenic E. coli (EPEC) (35.0%; 7/20), enteroinvasive E. coli (EIEC) (40.0%; 8/20), enterotoxigenic E. coli (15.0%; 3/20), STEC (40.0%; 10/20) and enteroaggregative E. coli (5.0%; 1/20). Escherichia coli as well as EPEC, EIEC and STEC pathotypes were most prevalent at the downstream 1 sampling point compared with the upstream. EPEC, EIEC and STEC were also detected in borehole samples (5.0%, 1/20).

Conclusions: The Iyi-Etu River and borehole water sources used for domestic and drinking purposes, respectively, at Amansea livestock market settlement are contaminated with some pathotypes of E. coli and the level of pollution may pose a public health risk to humans and animals during contact. Thus, public health measures including proper treatment of wastewater before disposal and continuous monitoring may help to learn the associated effect of DEC pollution in the area.

Venomous snakes are a potential hazard even after their death. Dead snakes or their severed heads can inflict bites under various bizarre circumstances and may result in envenomation. In this review, an effort has been made to discuss the circumstances under which envenomation from dead snakes can occur, the incidence and pathomechanics of such envenomation, clinical manifestations and management and preventive measures, as well as a review of the literature on this unique mode of snake envenomation.

Background: Snakebite is a neglected tropical disease that causes significant morbidity and mortality in India. In this study, we describe the clinical characteristics and outcomes of Echis carinatus sochureki envenoming from Western Rajasthan. We document the clinical ineffectiveness of the currently available Indian polyvalent antivenom in managing E. c. sochureki envenoming.

Methods: In this ambispective study, conducted from 14 April 2019 to 15 April 2024, we enrolled all patients presenting to our emergency department at a tertiary care centre in Jodhpur, Rajasthan, with a history of snakebite. After they provided informed consent, the demographic details, bite geo-location, bite-to-antivenom time, antivenom dose, coagulation profile, mortality and duration of hospital stay of those patients with E. c. sochureki envenoming were recorded.

Results: Of 210 patients screened, 105 had E. c. sochureki envenoming, 103 venom-induced consumption coagulopathy, 36 (34.3%) local bleeding and 55 (52.3%) systemic bleeding. The median bite-to-antivenom time was 2 (IQR: 1.13-4.0) h. The median antivenom dose was 22 (IQR: 10-30) vials. Of 92 patients who received antivenom, 63 (68.4%) were unresponsive. Total antivenom dose and geographical location (West zone) were significant predictors of antivenom unresponsiveness. Fifty-three of 70 patients (75.7%) had delayed hypofibrinogenaemia. The mean hospital stay was 8.3±7.1 d with nine (8.6%) mortalities.

Conclusions: Our study highlights the alarming finding of poor antivenom response to E. c. sochureki envenoming, with significant clinical bleeding and delayed coagulopathy. There is an urgent need for region-specific antivenom in Western India.

Background: Nearly 60 000 Indians die of snakebite envenoming each year. Most deaths occur in rural communities and remote tribal settlements. We describe snakebite-related epidemiology and health-seeking behaviours in a rural (Timiri) and remote tribal block (Jawadhu Hills) in Tamil Nadu, India.

Methods: This cross-sectional survey used structured questionnaires for information pertaining to snakebites and their treatment in the preceding year. Treatment-seeking behaviour from the moment reported until recovery was mapped. Traditional healers residing in the two blocks were also surveyed.

Results: Snakebite incidence and mortality were 174/100 000 population and 2.7/100 000 population in Jawadhu Hills and 194/100 000 population and 2.6/100 000 population in Timiri, respectively. More snakebite victims applied tourniquets in Jawadhu Hills (90%) than in Timiri (69%). Traditional healers were the first contact for 64% in Jawadhu Hills. Ambulances and buses were reported as unavailable in Jawadhu Hills. Traditional healers in Jawadhu Hills did not refer snakebite victims to hospitals.

Conclusions: Three challenges to snakebite mitigation in Indian rural and tribal communities highlighted in this study are potentially harmful first aid, a disconnect between traditional healers and the public health system and a lack of emergency transport to health facilities. Addressing these challenges would necessitate community awareness, traditional healer engagement and improved means of public transportation.

Background: Evidence has shown that the incidence of bacillary dysentery (BD) is associated with climatic factors. However, the lagged effects of climatic factors on BD are still unclear, especially lacking research evidence from arid and semi-arid regions. Therefore, this study aims to add new insights into this research field.

Methods: Spatial autocorrelation, time series analysis and spatiotemporal scans were used to perform descriptive analyses of BD cases from 2009 to 2019. On the basis of monthly data from 2015 to 2019, multivariable distributed lag non-linear models were used to investigate the lagged effects of climatic factors on BD.

Results: The hot spots for BD incidence are gradually decreasing and becoming increasingly concentrated in the southern part of Gansu Province. The maximum cumulative relative risks for monthly average temperature, sunshine duration, average relative humidity and precipitation were 3.21, 1.64, 1.55 and 1.41, respectively. The lagged effects peaked either in the current month or with a 1-month lag, and the shape of the exposure-response curve changed with the increase in maximum lag time. After stratification by per capita gross domestic product, there were differences in the effects.

Conclusions: Climatic factors can influence the incidence of BD, with effects varying across different lag times. It is imperative to vigilantly track the disparities in the incidence of BD attributable to economic factors.

Background: This study aimed to characterise the clinical and epidemiological profiles of dengue patients and their outcomes during an ongoing outbreak in a non-endemic region of Bangladesh.

Methods: This prospective observational study analysed 805 confirmed dengue cases during August-December 2023. Data on demographic, clinical and laboratory profiles, as well as outcomes, were gathered using a structured questionnaire. Statistical analysis was conducted using SPSS 25.

Results: The mean age of dengue patients was 31.5 (±12.2) y, with the majority being males (81.2%). All 805 patients experienced fever, 792 (98.4%) had headaches, 698 (86.7%) had myalgia, 601 (74.7%) had persistent vomiting and 598 (74.3%) had abdominal pain. Bleeding was observed in 191 (23.7%) patients and neurological symptoms were seen in 209 (25.9%) patients. Most patients (n=781, 97%) exhibited non-severe symptoms, while 3% (n=24) had severe symptoms. Among the 24 severe cases, four (16.7%) patients were reported to have encephalitis and one (4.2%) patient had meningoencephalitis. Moreover, 365 patients (45.3%) had travelled to an endemic region who were predominantly males (n=327, 89.6%). Most dengue patients recovered well with rapid fluid replacement therapy (n=754, 93.7%).

Conclusions: The 2023 dengue outbreak in a non-endemic area of Bangladesh primarily impacted males, young adults, with the majority presenting non-severe symptoms. Further studies are essential to validate and build upon these results.

Snakebite envenomation continues to affect lives globally, with >1.2 million envenomations and approximately 120 000 annual mortalities. Unfortunately, low- and middle-income countries (LMICs) contribute to >80% of these global statistics. With different targets set to minimize the impact of snakebite envenoming, such as halving the envenoming cases by 2030 from the World Health Organization (WHO), multiple initiatives are inevitable. Gender intersectionality and tropical disease research for infectious diseases of poverty, developed by the WHO, has championed the exploration of neglected diseases, stratifying them using gendered domains. However, minimal research using the gender intersectionality framework has been conducted to explore snakebite envenoming, especially among LMICs. Exploring snakebite envenomation through a gendered lens is critical in developing gender-specific interventions for the prevention and treatment of envenomation. This narrative review explores the available literature about snakebite envenomation in LMICs through a gender intersectionality lens. It provides insights into the existing gaps, especially regarding research using intersectionality frameworks and the gendered matrix. It further proposes avenues of research using these domains to understand snakebite envenomation, especially through the intersectionality lens.

Background: Little is known about snakebites by Naja samarensis, a species unique to the Philippines. The aim here is to describe the clinical and epidemiological characteristics of patients bitten by this medically important cobra in the Eastern Visayas.

Methods: A hospital-based prospective study analysed the features of snakebite patients attending Eastern Visayas Medical Center between June 2022 and May 2023. Logistic regression analysis identified the factors associated with severity.

Results: A total of 175 snakebite patients with five fatalities were included. Naja samarensis was most commonly implicated (n=49, 28.0%), although it could be definitively identified, by examining photographs of the snake responsible, in only four cases. The N. samarensis bites occurred in grass or rice fields, in daytime, and during farming activities, but the people bitten were most frequently students (34.7%) who were bitten at home (36.7%). Patients bitten by N. samarensis often presented with cytotoxic (63.3%) and neurotoxic signs (46.9%). Traditional remedies were common, resulting in delayed presentation to the hospital. Bites by N. samarensis, and older age (>44 y) were independently associated with severity (adjusted OR of 10.33 and 7.89, respectively).

Conclusion: Naja samarensis is a major cause of severe snakebites in this region. Pre-hospital treatment frequently involves wasted time and unproven traditional methods. Enhancement of public awareness is urgently needed. Development of a diagnostic test for species identification is warranted to improve future surveys and management.

Background: Despite the availability of antivenom, not all snakebite victims choose to seek allopathic care. This choice of care is likely to be determined by unexplored personal and external factors. We studied the factors influencing the choice of treatment and first aid measures among snakebite victims.

Methods: We conducted a population-based study integrating quantitative and qualitative research methods among snakebite victims in the preceding 12 months, selected from 8707 residents in Ampara District, representing typical rural Sri Lanka with a high snakebite burden. Interviewers collected data using questionnaires and in-depth interviews. Logistic regression and thematic analysis were performed.

Results: Among the 153 victims, 57.5% were farmers. As first aid, 19.6% practiced the application of tourniquets. The treatment choices were allopathic medicine (65.4%), ayurvedic/traditional (26.1%), faith healing (3.3%), self-medication (2.0%) and none (3.3%). Visible ambient light at the time of bite (adjusted odds ratio [aOR] 2.3 [95% confidence interval {CI} 1.1 to 4.7]), absence of local swelling (aOR 2.5 [95% CI 1.1 to 5.3]) and prolonged bleeding (aOR 8.6 [95% CI 1.9 to 33.3]) determined failure to seek allopathic treatment, while personal characteristics showed no influence. Qualitative inquiry revealed that the treatment choice was influenced by the ability of the victim or others to recognize envenoming features and the snake as venomous and awareness of the facilities available in hospitals.

Conclusions: The time of snakebite, recognition of the snake/envenoming and awareness of accessible medical services determined the treatment choice following snakebite.

Envenomations caused by viperid and some elapid snakebites are typically accompanied by local swelling and signs of inflammation that appear within a few hours of bite and spread centripetally for a few days. Often these changes are mistaken for signs of infection and are misdiagnosed as 'cellulitis'. This potentially results in unwarranted use of antibiotics. There are important clinical differences between the swelling caused by local envenomation vis-à-vis cellulitis. The term venom-induced spreading sterile inflammation (VISSI) is more appropriate as a diagnosis name for the local swelling caused by snakebite envenomation.