Learning from history in the midst of the COVID-19: epidemics/pandemics of antiquity up to the fall of the Western Roman Empire / Aprendiendo de la historia en medio del COVID-19: epidemias/pandemias de la antigüedad hasta la caída del Imperio Romano de Occidente

Abstract When humans discovered agriculture and livestock, they ceased to be nomads and began to settle in towns until they created large cities. From the first human settlements in Egypt, Mesopotamia, and the Anatolian Peninsula, populations were exposed and susceptible to new infectious agents, leading to epidemics and pandemics. Great civilizations emerged, such as Egypt, the land of Hatti, Israel, Greece, Carthage, and Rome, among others. Contact between different populations through wars or maritime trade is well documented and has been described as a source of epidemics throughout history. Epidemics described as plagues or pestilences, such as those of Egypt, the Hebrews, or the Hittites, are based on biblical texts or evidence such as tablets or hieroglyphic writings. We also reviewed classical books by authors such as Homer, Aeschylus, Herodotus of Halicarnassus, Thucydides, Diodorus Siculus, Dionysius of Halicarnassus, Titus Livius, Suetonius, and others; and described all epidemics/pandemics chronologically. This article describes the epidemics/pandemics for which there is written evidence from ancient Egypt to the fall of the Roman Empire. We should not be surprised when new epidemics/pandemics appear as causes of political and economic collapse, as this has been common throughout history, decimating, blocking, or even destroying cultures and civilizations repeatedly.

Resumen Cuando el hombre descubrió la agricultura y la ganadería, dejó de ser nómada y empezó a asentarse en pueblos hasta crear grandes ciudades. Desde los primeros asentamientos humanos en Egipto, Mesopotamia y la península de Anatolia, las poblaciones estuvieron expuestas y susceptibles a nuevos agentes infecciosos, dando lugar a epidemias y pandemias. Aparecieron grandes civilizaciones como Egipto, la Tierra de Hatti, Israel, Grecia, Cartago y Roma, entre otras. El contacto entre las distintas poblaciones a través de las guerras o el comercio marítimo está muy bien establecido y descrito como focos de epidemias a lo largo de la historia. Las epidemias descritas como plagas o pestilencias, como las que ocurrieron a los egipcios, los judíos, o los hititas, se describen con base en textos bíblicos o mediante evidencias como tablillas o escritos jeroglíficos. También revisamos libros clásicos de autores como Homero, Esquilo, Herodoto de Halicarnaso, Tucídides, Diodoro Sículo, Dionisio de Halicarnaso, Tito Livio, Suetonio, entre otros. Este artículo describe cronológicamente todas las epidemias/pandemias de las que existe evidencia a través de la escritura desde el antiguo Egipto hasta la caída del Imperio Romano. No debemos sorprendernos cuando aparecen nuevas epidemias/pandemias como causantes del colapso político y económico, ya que ha sido algo común a lo largo de la historia, diezmando, bloqueando o incluso destruyendo culturas y civilizaciones reiteradamente.

Aproximaciones sobre el acto de mirar: la peste de Azoth

Las neurociencias contemporáneas continúan separando el acto de ver en los procesos de la visión y los procesos de la motricidad ocular, sin plantear aun una explicación unificadora de ambos en una misma realidad: como el acto de mirar. El objetivo del presente artículo es explicar este acto a través de la serie de eventos neurológicos que suceden y entender que se mira con la conciencia. Se explican los procesos visuales en base al enfoque neurocientífico contemporáneo y la Teoría Sociobiológica Informacional en "La Peste de Azoth" de Nicolas Poussin. Mientras que la explicación tradicional de la neurociencia refiere que todo estímulo activa un receptor, siguiendo una vía nerviosa hasta el cerebro, desde la Teoría Sociobiológica Informacional, el acto de mirar es una actividad epiconsciente, una construcción que resulta de la suma emergente de los cinco niveles de complejidad. Estos integran este proceso en los movimientos que describen los ojos y la acción de lo que se mira simultáneamente. "La Peste de Azoth" muestra una ciudad azotada por la peste bubónica, con dos rasgos: maldición divina y presencia de miasmas respirables. Poussin no solo pintó los motivos de una explicación mágica (tradicional) y científica, sino también de una explicación tecnológica (bacteriológica) que emergería dos siglos después de su muerte. En conclusión, el acto de mirar desde la Teoría Sociobiológica Informacional, es un proceso que principian en el neocortex y que integra la información en cinco niveles. Esta explicación permite entender La Peste de Azoth" como un enfoque tecnológico adelantado.

Contemporary neurosciences continue to separate the act of seeing in the processes of vision and the processes of ocular motor skills, without even proposing a unifying explanation of both aspects of the same reality: as the act of looking. The aim of this article is to explain the act of looking through the series of neurological events that occur and to understand that one looks with consciousness. Visual processes are explained based on the contemporary neuroscientific approach and Informational Sociobiological Theory in Nicolas Poussin's "The Plague of Azoth". While the traditional explanation traditional explanation of neuroscience refers that every stimulus activates a receptor, following a nervous path to the brain, from the Informational Sociobiological Theory, the act of looking is an epiconscious activity, a construction that results from the sum emerging from the five levels of complexity. These integrate this process in the movements that describe the eyes and the action of what is seen simultaneously. "The Plague of Azoth" shows a city plagued by the bubonic plague, with two traits: a divine curse and the presence of breathable miasmas. Poussin not only painted the grounds for a magical (traditional) and scientific explanation, but also for a technological (bacteriological) explanation that would emerge two centuries after his death. In conclusion, the act of looking from the Informational Sociobiological Theory is a process that begins in the neocortex and that integrates information at five levels. This explanation allows us to understand "The Plague of Azoth" as an advanced technological approach.

Phenotypic characteristics of wild-type plague phage growth in different experimental environments / 中国热带医学

@#Abstract: Objective To observe the phenotypic characteristics of 3 wild-type plague phages under different experimental environments, providing scientific evidence for the identification of phage biological characteristics and the study of their interaction with host bacteria in the future. Methods The sensitivity of 3 wild-type plague phages were detected by using liquid culture method, emisolid medium method and micro-liquid culture method based on OmniLog TM microbial identification system. Results The growth result based on LB liquid medium showed that the growth of plague phage 476 for 20-24 hours at both 28 ℃ and 37 ℃was better than that of plague phages 087 and 072204 at 37 ℃, and the growth of plague phages 087 was better than that of plague phages 072204 at 37 ℃. With the attenuated plague bacterium EV76 as the host bacterium, phage 476 was able to form visible plaque on double-layer agar medium for 20-20 hours at both 28 ℃ and 37 ℃, phages 087 and 072204 were only able to form opaque plaque on double-layer agar medium for 20-24 hours at 37 ℃. The growth results based on OmniLogTM system showed that when plague phage was lysed in EV76 strain at 33 ℃, the first row appeared as a straight line with a peak of no more than 100 in the 96-well microplate curve chart. As the phage quantity decreased, the dilution plate appeared with growth curve similar to EV76 strain in turn, and the color of tetrazolium dyes in the experimental wells gradually deepened as the phage number decreased and the host bacteria number increased. Therefore, it indicates that phage 476 was sensitively at both 28 ℃ and 37 ℃, while phage 087 and 072204 were temperature-dependent only at 37 ℃ to attenuated plague bacterium EV76. Conclusions The lysing ability of 3 wild-type plague phages are temperature-dependent, and the growth results are consistent under the three experimental conditions.

Research on the clustered regularly interspaced short palindromic repeats genotyping of Yersinia pestis in the natural plague foci of Hainan Tibetan Autonomous Prefecture, Qinghai / 中国热带医学

@#Abstract: Objective　To investigate the clustered regularly interspaced short palindromic repeats (CRISPR) genotypes and regional distribution of Yersinia pestis strains in the natural plague foci of Hainan Tibetan Autonomous Prefecture of Qinghai Province (referred to as "Hainan prefecture") and provide a scientific basis for plague prevention and control in this area. Methods　A total of 36 representative Yersinia pestis strains, which were isolated from different host animals and insect vectors from 1954 to 2009 in Hainan Prefecture, were selected as experimental subjects. The DNAs were extracted using the traditional sodium dodecyl sulfate decomposition and phenol-chloroform method. Three pairs of CRISPR primers (YPa, Ypb, YPc) were used for PCR amplification, sequencing and analysis of the DNA of the tested strains, respectively, as a means to identify the CRISPR genotypes of Yersinia pestis in Hainan Prefecture. Results　A total of 17 spacers were observed among 36 strains of Yersinia pestis, including 9 of YPa, 5 of YPb and 3 of YPc. All strains were divided into 5 CRISPR gene clusters (Cb2, Cb4 ', Ca7, Ca7 ', Ca35 ') and 6 genotypes (G1, G9, G22, G22-A1 ', G26-A1 ', G26-A1 'A4 -). The G26-a1 ' was the main genotype, which was distributed in Gonghe, Guide and Xinghai County, and the G22 is the second type, which was distributed in Gonghe and Guide County. Conclusions　The genetic polymorphism of CRISPR loci of Yersinia pestis strains in Hainan was high, and the regional distribution characteristics of Yersinia pestis strains with different genotypes were significant.

Clinical application and effect analysis of remote multi-disciplinary team in the treatment of bubonic plague secondary to septicemic plague / 中华地方病学杂志

Objective:To study the remote multi-disciplinary team (MDT) model in diagnosis and treatment of plague, in order to provide scientific basis for clinical treatment of plague.Methods:A retrospective analysis was made on the diagnosis and treatment process of a case of bubonic plague, a sudden imported Class A infectious disease, which was secondary to septicemic plague, involving a remote MDT team consisting of the Infectious Diseases Department, Intensive Care Unit, Respiratory and Critical Care Department, Cardiology Department, Pharmacy Department, and Nosocomial Infection Department of the General Hospital of Ningxia Medical University.Results:The patient was a middle-aged female who was engaged in herding work on the grassland. The first symptom was a sudden pain in the left lower abdomen for three days, accompanied by chest tightness and shortness of breath. After hospitalization, blood culture indicated Yersinia, abdominal CT indicated left lower abdominal lymph node enlargement, and lymph node puncture fluid was positive for Yersinia pestis nucleic acid. Combined with clinical symptoms and signs, the patient was diagnosed as bubonic plague secondary to septicemic plague, and was isolated for treatment. After remote MDT consultation, comprehensive treatment was given, including anti-infection treatment of streptomycin and ciprofloxacin, short-term application of hormones, nutritional support, and local application of chloramphenicol ointment, etc. Secondary acute pancreatitis occurred during the course of the disease, which improved after symptomatic treatment. Finally, after 20 days of treatment, MDT expert group assessed that it met the discharge criteria. No abnormalities were found in follow-up visits outside the hospital. Conclusion:The remote MDT is effective in the treatment of bubonic plague secondary to septicemic plague, which is worth popularizing.

Research progress on sensitivity, resistance and mechanism of plague infected animals to Yersinia pestis / 中华地方病学杂志

The sensitivity and resistance of host animals to Yersinia pestis are different among species and regions, and the indicator animals have natural resistance to Yersinia pestis. This article reviews the research progress on sensitivity, resistance and mechanism of plague infected animals to Yersinia pestis, in order to help improve the ecological research of plague and the prevention and control of plague.

Research progress of Yersinia pestis phage and their receptors / 中华地方病学杂志

Yersinia pestis phage is a virus that is parasitic within Yersinia pestis and can specifically lyses Yersinia pestis. The adsorption sites of phage infesting host bacteria are called receptor binding protein (RBP), including extracellular membrane protein, lipopolysaccharide, teichoteic acid, pili, flagella, capsular polysaccharide, etc., of which extracellular membrane protein and lipopolysaccharide are the receptors of Yersinia pestis phage. RBP plays a decisive role in the process of Yersinia pestis phage infecting Yersinia pestis. Therefore, the classification, isolation and application of Yersinia pestis phage are summarized; the research progress in identification and structure of Yersinia pestis phage receptor is analyzed, which is helpful in understanding the cleavage mechanism of Yersinia pestis phage and the interaction mode with Yersinia pestis from the molecular level, and provide more powerful support for in-depth study on Yersinia pestis phage receptor.

Analysis of plague surveillance results and risk assessment in Yulin City, Shaanxi Province, 2011 - 2021 / 中华地方病学杂志

Objective:To analyze the epidemiological characteristics and related indicators of plague in Yulin City, Shaanxi Province, and to evaluate the risk of plague epidemic in the future and formulate scientific and reasonable prevention and control measures.Methods:The plague surveillance data of national (Dingbian County) and provincial (Yuyang District, Jingbian County, Hengshan District, Shenmu City, Fugu County) plague monitoring sites in Yulin City from 2011 to 2021 were collected through the China Disease Prevention and Control Information System Pestis Prevention and Control Management Information System, and the plague epidemic situation among humans and animals, the main host animals and their flea infection were analyzed by descriptive epidemiological methods. The expert consultation method and plague risk assessment tool V1.0 were used to assess the epidemic risk of the plague in Yulin City.Results:There was no human and animal plague epidemic in Yulin City from 2011 to 2021. In national monitoring site, the density of main host animal was 5.79/hm 2, ranging from 3.02/hm 2 to 9.08/hm 2,the dominant species was Mongolian gerbil, accounting for 98.21% (3 402/3 464); the capture rate of wild nocturnal rodents was 1.27% (350/27 600), ranging from 0.21% to 3.83%, the dominant species was Cricetulus barabensis, accounting for 44.86% (157/350); the flea infection rate of the rodent body was 16.91% (768/4 541), with a flea index of 0.40, the dominant flea species was the Nosopsyllus laeviceps kuzenkov, accounting for 66.54% (1 203/1 808). In provincial monitoring site, the density of main host animals was 0.49/hm 2, ranging from 0.31/hm 2 to 0.67/hm 2, the dominant species was Alashan ground squirrel, accounting for 63.61% (194/305); the capture rate of nocturnal rodents in the wild was 1.76% (560/31 795), ranging from 0.89% to 3.93%, the dominant species was Roborovski dwarf hamster, accounting for 26.61% (149/560); the capture rate of domestic rats was 2.37% (397/16 750), ranging from 1.48% to 3.10%, the rodents included Rattus norvegicus (47.36%, 188/397) and house mouse (52.64%, 209/397); the flea infection rate of the rat body was 13.26% (182/1 373), with a flea index of 0.40; the dominant flea species was Ophthalmopsylla jettmari, accounting for 45.23% (251/555). The 5 281 pathogenic culture samples and 2 110 serological test samples were all negative. The Pearson correlation analysis results showed that there was no correlation between rodent density and flea infection rate or flea index at national and provincial monitoring sites ( r = - 0.26, - 0.48, 0.09, 0.12, P > 0.05), while flea infection rate and flea index were positively correlated ( r = 0.67, 0.81, P < 0.05). In 2022, Yulin City, Shaanxi Province was not ruled out the possibility of human plague epidemic, and the risk of plague epidemic among animals was high. Conclusions:From 2011 to 2021, the density of the main host animals at the national and provincial monitoring sites in Yulin City has remained at a low level, and the flea index has increased. There is a risk of plague epidemic in Yulin City, so the monitoring work should be further strengthened, and emergency supplies and capacity reserves should be well prepared.

Analysis of plague monitoring results in natural focus of Marmota sibirica plague in Hulunbuir Plateau from 2009 to 2020 / 中华地方病学杂志

Objective:To analyze the plague monitoring results of Marmota sibirica plague natural focus in Hulunbuir Plateau, and to study the characteristics of development and variation of the plague focus. Methods:From 2009 to 2020, monitoring was conducted in Manzhouli City, Prairie Chenbarhu Banner, Xin Barag Left Banner, and Xin Barag Right Banner from May to September each year. The one-day bow-clip method was used to investigate the density of the Spermophilus dauricus, and the 5-meter clamp method was used to investigate other small rodents. The classification and identification of ectoparasite fleas were done by using low power microscope. According to "Diagnostic Criteria for Plague" (WS 279-2008), the detectable materials of rats and fleas were tested, and Yersinia pestis was isolated and cultured. The serums of collected rats were detected by indirect hemagglutination test. Results:From 2009 to 2020, the average density of dauricus in Marmota sibirica plague natural focus of Hulunbuir Plateau was 0.45/hm 2, and the capture rate of other small rodents was 1.25% (787/63 091). A total of 9 species, 8 genera and 4 families of rodents were captured. The total flea infection rate of Spermophilus dauricus was 28.37% (1 945/6 856) and the fleas index was 1.04. A total of 3 species, 3 genera and 2 families of fleas were collected. A total of 6 674 Spermophilus dauricus were dissected and 6 787 fleas were cultured in 2 537 groups. The Yersinia pestis test was negative. A total of 6 795 serum samples from Spermophilus dauricus were detected, of which 11 were positive with a positive detection rate of 0.16%. The highest titer of positive serum was 1∶1 280. Indirect hemagglutination test positive materials were found for 5 consecutive years from 2010 to 2014; the positive serums were found in Manzhouli City and Xin Barag Right Banner. Conclusions:The Yersinia pestis antibady positive serum of Spermophilus dauricus has been detected in Marmota sibirica plague focus of Hulunbuir Plateau for many years, which is worthy of high vigilance. In the future, continuous surveillance should be carried out, bacterial detection should be strengthened, possible plague outbreaks should be detected in time, and various plague prevention and control should be done well.

Investigation and analysis of plague epidemic Yersinia infection in Marmota himalayana, Yugur Autonomous County of Sunan, Gansu Province / 中华地方病学杂志

Objective:To study the epidemic situation of Marmota himalayana plague and Yersinias infection in Yugur Autonomous County of Sunan (Sunan County) of Gansu Province, and to provide new ideas for prevention and control of plague. Methods:From 2014 to 2018, liver and spleen, cecum, throat swabs and blood samples of Marmota himalayana were collected on the spot in Sunan County, where Yersinia strains were isolated and identified, and plague F1 antigen and antibody were detected. Results:A total of 634 liver and spleen samples, 427 cecum samples and 426 throat swabs samples were collected from Marmota himalayana, and 23 strains of Yersinia pestis, 2 strains of Yersinia marcescens, and 1 strain of Yersinia flexneri were detected, with the detection rates of 3.63% (23/634), 0.47% (2/427) and 0.23% (1/426), respectively. The detection rate of Yersinia pestis in different years was statistically significantly different (χ 2 = 13.19, P = 0.010). A total of 1 822 serum samples of Marmota himalayana were detected, and 5 F1 antibody positive samples were detected, with a positive rate of 0.27%, the difference of positive rate between different years was statistically significant (χ 2 = 25.22, P < 0.001); 282 liver and spleen tissue homogenates of Marmota himalayana were detected, 22 F1 antigen positive samples were detected, the positive rate was 7.80%, and there was no statistically significant difference between different years (χ 2 = 7.85, P = 0.097). The 23 strains of Yersinia pestis detected were distributed in Mati Tibetan Township (12 strains), Dahe Township (6 strains) and Qifeng Tibetan Township (5 strains); 1 strain of Yersinia flexneri and 2 strains of Yersinia marcescens were both located in Dahe Township. Conclusion:There is an epidemic of plague among animals in Sunan County from 2014 to 2018, and the areas where Yersinia pestis and non pathogenic Yersinia are detected overlapped.

Isolation and identification of plague phage from Suncus murinus in Yunnan Province and its epidemiological significance / 中华地方病学杂志

Objective:To study the basic situation of Yunnan Province Suncus murinus carrying plague phage and to explore its epidemiological significance. Methods:From 2015 to 2018, a survey of plague host animals was carried out in 10 investigation sites in the historical plague foci, new plague foci (after 1982) and stubborn plague foci of domestric mouse in Yunnan Province. The plague phage was isolated and cultured from the intestinal specimens of Suncus murinus. The growth of plaque was observed by double-layer plate method, and the morphology and structure of plague phage were observed under electron microscope. At the same time, intestinal samples were taken to detect the structural gene caf1 of F1 antigen of Yersinia pestis. Results:In this study, a total of 157 Suncus murinus were captured and 16 strains of plague phage were isolated, with a total isolation rate of 10.19%. There was no difference in plague phage isolation rate between historical plague foci (10.00%, 1/10) and stubborn plague foci (16.22%, 12/74), new plague foci (4.11%, 3/73, χ 2 = 0.00, P = 0.965; Fisher test, P = 1.000). However, there was a difference in plague phage isolation rate between stubborn plague foci and new plague foci (χ 2 = 5.88, P = 0.015). There was no significant difference in the isolation rate of plague phage among different sex, growth period and habitat ( P > 0.05). The plaque morphology of the isolated plague phage was diverse, of which four strains were myotavirus phages; and all samples were negative for F1 antigen structural gene caf1. Conclusions:Suncus murinus is widely distributed in the domestic mouse plague foci in Yunnan Province, and the animals carry a certain number of plague phage. Regular surveillance of Suncus murinus and their plague phage has a certain guiding significance for the surveillance and early warning of plague in Yunnan Province.

Phenotype and genotyping of Yersinia pestis in China / 中华地方病学杂志

Objective:To study the phenotype and genotype distribution of Yersinia pestis ( Y. pestis) in different natural foci of plague in China, so as to provide scientific basis for plague prevention and control. Methods:A total of 2 184 strains of Y. pestis isolated from different time periods, regions, hosts and vectors in 11 plague natural foci of China since 1943 were selected for biochemical type identification, glycolysis test, virulence factor test [capsule antigen (F1), pesticin Ⅰ (Pst Ⅰ), virulence antigen factor (VWa), pigmentation factor (Pgm)], different region (DFR) typing and clustered regularly interspaced short palindromic repeats (CRISPR) typing. Results:There were 16 biochemical types of Y. pestis in the natural foci of plague in China, and each biochemical type showed obvious regional distribution in each foci. Most strains were positive for ass hide glue glycolysis (89.79%, 1 961/2 184), maltose (80.13%, 1 750/2 184), glycerol (94.23%, 2 058/2 184), and denitrification (82.78%, 1 808/2 184), and negative for rhamnose (88.78%, 1 939/2 184) and melibiose (85.62%, 1 870/2 184). Virulence factor test results showed that 99.95% (2 183/2 184) of Y. pestis were F1 positive; 99.73% (2 178/2 184) of Y. pestis can produce Pst Ⅰ; 73.31% (1 601/2 184) of Y. pestis were VWa positive and 26.69% (583/2 184) were VWa negative; Pgm positive strains accounted for 72.62% (1 586/2 184), Pgm negative strains accounted for 21.52% (470/2 184), and Pgm mixed type strains accounted for 5.86% (128/2 184). According to DFR typing results, there were 52 genotypes in 2 184 strains of Y. pestis, of which 19 were major genotypes and 33 were minor genotypes. CRISPR typing revealed 16 major genotypes, of which 7 were newly discovered. Conclusion:The phenotypes and genotypes of Y. pestis in various natural foci of plague in China are diverse and have geographical distribution characteristics.

The Association Between Serum Vitamin D Levels and Serum Cathelicidin Antimicrobial Peptide (CAMP) Levels Among Tuberculosis Patients in Comparison with Control Subjects

Objectives: To compare the serum vitamin D and serum cathelicidin antimicrobial peptide (CAMP) levels among tuberculosis patients and healthy subjects and to determine the association between serum vitamin D and cathelicidin in tuberculosis. Materials and Methods: This is a case-control study carried out at the pulmonary medicine and pediatrics departments of a tertiary care hospital in Chengalpattu. The study included 180 tuberculosis cases and 90 control subjects of both sexes between the age group of 1 to 80 years. Serum was used to estimate vitamin D and CAMP. The study was analyzed using SPSS version 21 (IBM Corp. Armonk, New York). The results were evaluated using the chi-square test at a 95% confidence interval, and P value <.05 was considered highly significant. Results: This study observed vitamin D deficiency, vitamin D insufficiency, and optimum vitamin D among 55%, 41%, and 3.89% tuberculosis cases, respectively. Similarly, vitamin D deficiency, vitamin D insufficiency, and optimum vitamin D were seen in 40%, 50%, and 10% healthy controls, respectively. Conclusion: This study found no association between serum vitamin D and serum CAMP levels in tuberculosis patients and healthy controls.

THE PLAGUE BY ALBERT CAMUS AND WHY EVERYONE IS REREADING IT IN TIMES OF COVID-19 PANDEMIC

The Plague is the story of a plague-stricken town in Oran (Algeria), and it chronicles the life of its citizens and how they deal with morbidity, absurdity, separation, etc. It was initially perceived as allegory of France under Nazi occupation, a symbol against fascism, colonization, etc. But in the times of Covid-19 pandemic, it is the first time it has been read in the most literal and crude sense. This paper aims at analyzing the key elements of the book with the startling parallels of today's world.

Epidemiological analysis of animal plague in natural plague focus of Himalayan Marmot in Yumen City of Gansu Province from 2014 to 2021 / 中华地方病学杂志

Objective:To learn about the epidemic law of animal plague in natural plague focus of Himalayan Marmot in Yumen City of Gansu Province, to explore the epidemiological characteristics of plague in the area and to provide scientific basis for formulating prevention and control strategies of the plague. Methods:The animal plague surveillance data of natural plague focus of Himalayan Marmot in Yumen City, Gansu Province from 2014 to 2021 were collected, main host density, rate of infected with fleas, flea index, small rodent species, bacteriology, serology were studied. Excel 2007 software was used to analyze the plague epidemic situation in the focus. Results:From 2014 to 2021, the total average density was 0.06 per hm 2 of the marmots. A total of 19 300 traps were placed, and 209 rats were caught, with an average catch rate of 1.08%. Among them, Dipus sagitta (59.81%, 125/209) and Mongolian Five-toed Jerboa(31.10%, 65/209) were dominant small rodent species. Totally 877 marmots were checked, 184 with flea. The rate of infected with fleas of marmots was 20.98%, with a flea index of 1.00, Callopsylla dolabris (52.69%, 461/875) and Oropsylla silantiewi (47.20%, 413/875) were dominant species in vector. The rate of infected with fleas of burrow was 7.72% (173/2 241), with a flea index of 0.20. A total of 39 strains of Yersinia pestis were isolated from infected animals. Among them, 35 strains from the marmots, and 4 strains from vectors. Totally 913 serum samples were checked from marmots and shepherd dog, the positive serum was 34. Among them, the positive rate of shepherd dog was 13.98% (33/236). Conclusions:The plague epidemic situation in natural plague focus of Himalayan Marmot in Yumen City of Gansu Province is still serious. The monitoring of plague should be strengthened, and the comprehensive measures for prevention and control of the plague should be carried out to prevent a outbreak of the plague in human being.

CRISPR genotyping of Yersinia pestis in the plague natural foci of Qinghai-Tibet Plateau / 中华地方病学杂志

Objective:To investigate the genotypes of clustered regularly interspaced short palindromic repeats (CRISPR) of Yersinia pestis ( Y. pestis) and it's regional distribution in the plague natural foci of Qinghai-Tibet Plateau. Methods:In this study, 1 004 strains of Y. pestis isolated from different hosts and vectors in different regions from 1954 to 2011 were selected as experimental objects, which preserved in Qinghai Institute for Endemic Disease Prevention and Control, and DNA of Y. pestis was extracted by traditional phenol-chloroform method. Three CRISPR loci (YPa, YPb and YPc) were amplified by PCR and sequenced, respectively, and the CRISPR sequences were compared with the CRISPRDictionary database recently reported in the literature to identify CRISPR spacer. For the spacer discovered for the first time at each CRISPR locus, Blast sequence alignment was performed in the National Center for Biotechnology Information (NCBI) database to speculate the source of gene sequence. Genotyping of Y. pestis from Qinghai-Tibet Plateau was performed based on the polymorphism of CRISPR spacer array. Results:A total of 53 spacers were found in 1 004 strains of Y. pestis, of which 6 spacers were newly discovered, namely a105, a106, a107, b51, b52 and c14. The 1 004 strains of Y. pestis were divided into 10 groups with 44 different CRISPR genotypes, and 15 new genotypes were found. The dominant genotypes of Y. pestis were G26-a1', G7, G22, G24-a1', G22-a1', G9 and G26-a1'a60 in Himalayan Marmot plague natural foci, and G37-a6' in Qinghai Microtinae plague natural foci. Conclusion:The CRISPR genotypes of Y. pestis in the plague natural foci of Qinghai-Tibet Plateau are high diverse and have significant regional distribution characteristics.

The epidemic situation and influencing factors of plague in the foci of Meriones unguiculatus in Inner Mongolia Plateau / 中华地方病学杂志

Objective:To analyze the epidemic situation of plague among animals in the foci of Meriones unguiculatus in Inner Mongolia Plateau, and to find out key influencing factors affecting the epidemic of the plague, and to provide theoretical basis for the prediction, early warning and risk assessment of the plague. Methods:The monitoring data including gerbils density, gerbils body flea index, plague epidemic intensity, etc., as well as environmental data including temperature, precipitation and El Ni?o activity (Southern Oscillation Index, SOI) from 19 banners (counties, cities and districts) in Ulanqab Plateau area, the foci of Meriones unguiculatus in Inner Mongolia Plateau were selected. The methods of correlation analysis, structural equation model and rank correlation were used to analyze the epidemic and key influencing factors of plague among animals in the foci. Results:The plague epidemic cycle in the foci of Meriones unguiculatus in Inner Mongolia Plateau was 5 to 10 years. The correlation analysis results showed that all the factors had influence on each other. Structural equation model screened out that the main influencing factors of plague epidemic were SOI, gerbils density and temperature. SOI had a negative effect on plague epidemic intensity (-0.022) and temperature (-0.029), while gerbils density had a positive effect on plague epidemic intensity (0.014), and temperature had a negative effect on plague epidemic intensity (-0.065). In rank correlation, when the gerbils density was at a high value, the probability of high plague epidemic intensity in that year was 4/9; when SOI was at a low value, the probability was 5/9; when the temperature was at a low value, the probability was 5/9. When the plague epidemic intensity was at a high value in that year, the probability of the plague epidemic intensity being high in the following year was 5/8; when the gerbils density was at a high value in that year, the probability was 4/9; when SOI was at a low value in that year, the probability was 4/9. Conclusion:Climate and biological factors can affect prevalence of plague, and countermeasures should be taken in advance to prevent plague outbreaks when El Ni?o phenomenon, low temperature, high density of gerbils, and high previous-year prevalence of plague appear.

Investigation on plague foci and epidemic risk analysis in Qiaojia County, Yunnan / 中国热带医学

@#Abstract: Objective　A survey on the plague foci in Qiaojia County of Jinsha River Basin was conducted to understand the composition of plague host vectors and the prevalence of plague among animals, to explore the occurrence and epidemic risk of plague, and to provide scientific basis for plague monitoring and control in this area. Methods　Seven villages and towns in Qiaojia County were selected as the research areas, and the cage night method and the clamp line method were used to investigate the small mammals and their surface parasitic fleas. The host animal organs, serum and surface parasitic flea's samples were collected. The plague indicator animal serum was collected simultaneously on the spot, and the collected host animal organs and flea's samples were cultured and detected for Yersinia pestis. The indirect hemagglutination test (IHA) was used to detect the fraction 1 capsular antigen (F1) antibody of the host animal and the indicator animal serum samples. Results　A total of 525 small mammals belonging to 3 orders, 6 families, 12 genera and 23 species were captured. The dominant species in farming areas were Apodemus chevrieri (31.05%), Niviventer confucianus (13.90%) and Anourosorex squamipes Milne-Edwards (11.43%). The dominant species in residential areas were Rattus norvegicus (66.67%) and Rattus tanezumi (20.00%). The rat densities in agricultural and residential areas were 20.98% and 1.00%, respectively. A total of 277 external parasitic fleas belonging to 15 species, 13 genera, 5 families were collected. The dominant species were Palaeopsylla remota (22.02%), Neopsylla specialis specialis (20.58%), Frontopsylla diqingensis (18.77%) and Ctenophthalmus (Sinoctenophthalmus) quadratus (11.55%), and the rat fleas index was 0.53. No Yersinia pestis was isolated from all rodent organs and flea samples. A total of 167 serum samples from dogs and 15 serum samples from rats were collected, and plague F1 antibody was detected by IHA. IHA detection of plague F1 antibody were negative. Conclusions　Qiaojia County has the distribution of the main host and main vector of plague, and the rat density is high, but the rat body flea index is low. There is no positive detection of plague host animals, vector fleas and indicator animals. It can be considered that the risk of plague occurrence and epidemic in the region is not high in the near future. It is necessary to further strengthen the monitoring and control of plague and other rodent-borne diseases in the region.

Research progress on the relationship between formyl peptide receptor 1 and plague infection / 中华地方病学杂志

Inflammatory response is an important immune mechanism of the body, formyl peptide receptor (FPR) 1 is a pattern recognition receptor expressed in immune cells, and its binding with ligands is the basis for immune cells to realize various physiological functions in infectious inflammation. FPR1 plays an important role in inflammatory response, and changes in amino acids caused by its gene polymorphism affect a variety of diseases. Plague is an inflammatory disease caused by Yersinia pestis. Yersinia pestis, its pathogen, has a strong ability of immune escape and attacks on host immune cells. In this paper, FPR structural characteristics, expression and distribution, FPR1 gene polymorphism, ligand and its relationship with plague are reviewed, with a view to further understanding the role of FPR1 in the occurrence and development of plague.

Epidemic situation and prevention and control strategies of plague in Gansu Province at present / 中华地方病学杂志

Plague natural foci in Gansu Province are large in area and widely distributed, and the epidemic status is different in each focus. Some plague natural foci have been resting for many years and are under stable control. In other plague natural foci, the epidemic of plague among animals is relatively active, and dozens of strains of Yersinia pestis can be isolated every year. The plague among animals spreads to the humans from time to time, and the cases of human plague are more severe, short in course of disease, and high in mortality. In recent years, with the sharp increase of migrant workers engaged in grazing and engineering construction in plague natural foci, opportunities to actively contact infected animals such as marmots, hares and sheepdogs have increased, resulting in an increase of human plague cases. In addition, the behaviors of illegal hunting, trafficking and sale of marmots cannot be stopped, resulting in human plague throughout the year. Therefore, the party committees and governments at all levels and the health administrative departments in Gansu Province have formulated the plague prevention and control measures suitable for this region according to the epidemic characteristics of plague among animals and humans. In this paper, the characteristics of plague epidemic situation at present and the prevention and control measures adopted in Gansu Province are discussed, in order to provide scientific basis and guidance for optimizing plague prevention and control measures in the future.