Cases Of Plague Research Articles

Genomic diversity and transmission patterns of Yersinia pestis in Inner Mongolia Autonomous Region, China

According to WHO, plague, caused by Yersinia pestis, has resurged since 2000. Inner Mongolia, harboring a quarter of China’s plague foci, has accounted for 80% of national plague cases in the past five years. Despite its pivotal role in Chinese plague epidemiology, the genetic diversity and transmission dynamics of Y. pestis in this region remain under-investigated. Our analysis of 585 Y. pestis strains from Inner Mongolia (1948–2021) revealed three primary lineages, with 2.MED3 being predominant. We further delineated seven sub-phylogroups in 2.MED3, with 2.MED3.1.2 and 2.MED3.1.4 showing recent dominance. These two subgroups reveal dual transmission patterns: localized short-distance spread and long-distance dispersals over 300 km. Xilingol League is highlighted as a key source and reservoir for Y. pestis, predominantly spreading from central-eastern to southwestern Inner Mongolia, including occasional reverse transmissions. These findings enhance understanding of Y. pestis diversity and transmission in Inner Mongolia, aiding in enhanced surveillance and control measures.

Status and analysis of undetected plague cases in Yunnan Province, China.

The virulence of Yersinia pestis strains in the Rattus flavipectus plague focus is relatively low. The purpose of this study was to investigate the undetected, sporadic plague cases in plague foci and provide the basis for plague prevention and control. A 3-year-old plague-confirmed case was investigated in the R. flavipectus plague focus of Yunnan Province in 2020 due to the intensive screening for fever symptoms during the coronavirus disease 2019 (COVID-19) pandemic. Epidemiological investigation, laboratory testing, and clinical treatment were conducted for the case. The expanded survey was carried out around the case within a 7-km radius, including the resident population, domesticated dogs, and rats. PCR and indirect hemagglutination tests were performed on the collected samples. The isolation rates of Y. pestis were 100.0% (7 out of 7) in dead rats and 4.00% (3 out of 75) in live rats in the survey area of the foci. A total of 5.00% (6 out of 120) of the domesticated dogs were F1 antibody positive. Nine local people were determined for plague infection recently (0.92%, 9 out of 978). The locations of human cases coincided with the Y. pestis epidemic area among the animals. This study discovered the existence of plague cases that had not been detected by routine surveillance in the R. flavipectus plague focus, and the actual epidemic of human infection may be underestimated.

Unveiling Milan's hidden cases of plague occurred in autumn 1629, before the great 1630 epidemic.

In the summer of 1630, Milan experienced the most devastating plague epidemic in its history. In this study, addressed to investigate the earliest phases of the epidemic in the autumn of 1629, a set of unpublished and only partially known primary sources produced by the city's Officium Sanitatis was consulted and compared for the first time. Including those of two foreigners who died in the Lazzaretto, it was possible to ascertain a total of 39 cases of plague occurred in Milan between 9 October 1629 and the first weeks of 1630, of which 29 (74.4%) ended in death. Seven deaths presumably occurred at home were not recorded in the Liber Mortuorum, in which at least three other deaths caused by plague were deliberately attributed to a different cause. In particular, the case of the Vicario di Provisione in charge, Alfonso Visconti, probably the first death from plague occurred in Milan that year, was deliberately concealed for political reasons. Nevertheless, the spread of the disease remained limited in autumn 1629 and it was probably stopped until the following spring more by climatic factors than by the interventions of public health officials.

Imaging analysis of pneumonic plague infection in Xizang, China: a case report and literature review

BackgroundPlague is an acute infectious disease caused by the Yersinia pestis. Historically, it has been a major pandemic with high mortality rates, known as the “Black Death” in the 14th century, which resulted in millions of deaths in Europe. With increasing economic prosperity, more and more people are traveling to Xizang. However, this trend also hides significant safety hazards. Currently, there are few recent reports on plague, especially those with imaging manifestations available. In this study, we report the detailed clinical and radiological data of the patient with pneumonic plague in Xizang, China, in 2023.Case presentationWe report a case of pneumonic plague in Xizang, which occurred in a herdsman living in an area where dead marmots were found. The patient presented with symptoms such as fever, hemoptysis, dyspnea and coma. Chest computed tomography (CT) scans showed multiple nodules distributed in the central regions of lung lobes, consolidation distributed in secondary pulmonary lobules, and had a gravity-dependent distribution pattern. These imaging findings were consistent with pulmonary hemorrhage and diffuse alveolar damage. Despite emergency treatment, the patient died within 48 h of admission. Through retrospective medical history investigation, laboratory examination and autopsy, the final diagnosis was confirmed as pneumonic plague.ConclusionPneumonic plague is the most deadly infectious disease, and its pathological features mainly include damage to the alveoli, pulmonary hemorrhage, and pulmonary edema. Corresponding to CT, it manifests as acute and rapidly progressing pneumonia, alveolar damage, and pulmonary hemorrhage. The value of this article lies in the completeness and typicality of the imaging data, vivid hand-drawn illustrations of transmission pathways, and comprehensive literature review, all of which serve to enhance public understanding of plague and play an important warning role.

An overview of the first human case of Bubonic plague detected in Bugat settlement, Gobi-Altai province in Mongolia

On June 27th, 2023, Mongolia registered its first case of bubonic plague in the Bugat settlement, Gobi-Altai province. Cases in this outbreak are widespread throughout the country with multiple close contacts identified and monitored. Environmental surveillance, including the testing of marmots, picked up the presence of Yersinia Pestis in many samples prior to the beginning of the outbreak. Marmots are seen as a delicacy in Mongolia which presents a challenge when preventing animal to human transmission of bubonic plague via the consumption of raw undercooked marmot meat. Although bubonic plague is endemic in Mongolia, cases are often sporadic and mostly registered in the western provinces of the region however, one case was recorded in the capital city of Ulan Bator on the eastern side of the country. The nature of this outbreak highlights the importance of effective preventive measures such as, PPE, awareness campaigns, health literacy and safe food handling practices.

Knowledge and practices related to plague persistence in plague-endemic foci, Mbulu District, Tanzania.

Plague continues to be a major public health concern in African countries. Several social practices and environmental conditions have been associated with the reoccurrence of bubonic plague, especially in places where the disease is prevalent. Therefore, it remains important to understand people knowledge, behavior and practices related to disease risks in order to identify factors that may hinder prevention and control strategies in the foci. A study survey of 100 households was conducted in Mbulu district to assess plague knowledge, factors that influence flea bite and measures used for rodent and flea control. Majority of participants (86%) were familiar with the plague disease and about (50%) mentioned swelling lymph nodes as a common symptom. Most of the participants (62%) claimed to observe human plague cases during the long rain season. The majority of participants (97%) reported to experience flea bite in their domestic settings, with most stating that they experienced more flea bites during the dry season. Houses with livestock had a greater likelihood of flea bite (OR = 2.7; 95% CI: 0.36-18.80, p = 0.267) compared to houses with no livestock. Furthermore, residents reported using both local and chemical methods to control rodents and flea inside houses. Most respondents preferred using local methods in flea control. Respondents stated that the efficacy of flea control methods being applied ranged from few days to several months. There was limited knowledge of the residual effects of the agricultural chemicals being used to control fleas among the surveyed community. Our study highlights the importance of raising awareness and adopting effective control methods for controlling fleas and lower the risk of plague transmission and other flea borne diseases in the local communities. Sensitization of the local community on the use of appropriate chemicals for flea control is urgent to avoid any potential long-term impacts of the residual effects on the health of the local communities.

Development and evaluation of a multi-target droplet digital PCR assay for highly sensitive and specific detection of Yersinia pestis.

Plague, caused by the bacterium Yersinia pestis, is a zoonotic disease that poses considerable threats to human health. Nucleic acid tests are crucial for plague surveillance and the rapid detection of Y. pestis. However, inhibitors in complex samples such as soil and animal tissues often hamper nucleic acid detection, leading to a reduced rate of identifying low concentrations of Y. pestis. To address this challenge, we developed a sensitive and specific droplet digital polymerase chain reaction (ddPCR) assay for detecting Y. pestis DNA from soil and animal tissue samples. Three genes (ypo2088, caf1, and pla) from Y. pestis were used to develop a multi-target ddPCR assay. The limits of detection (LoD), reproducibility, and specificity were assessed for bacterial genomic DNA samples. The ability of the assay to detect low concentrations of Y. pestis DNA from simulated soil and mouse liver tissue samples was respectively evaluated and compared with that of quantitative real-time PCR (qPCR). The results showed that the ddPCR LoDs ranged from 6.2 to 15.4 copies/reaction for the target genes, with good reproducibility and high specificity for Y. pestis. By testing 130 soil and mouse liver tissue samples spiked with Y. pestis, the ddPCR assay exhibited a better sensitivity than that of the qPCR assay used in the study, with LoDs of 102 colony forming units (CFU)/100 mg soil and 103 CFU/20 mg liver. Moreover, the assay presented good quantitative linearity (R2 = 0.99) for Y. pestis at 103-106 CFU/sample for soil and liver samples. The ddPCR assay presented good performance for detecting Y. pestis DNA from soil and mouse tissue samples, showing great potential for improving the detection rate of low concentrations of Y. pestis in plague surveillance and facilitating the early diagnosis of plague cases.

Intraspecific diversity of Meriones persicus (Rodentia; Gerbillinae), the main plague reservoir in Iran, and its connection to enzootic plague in Iran.

Plague, a lethal zoonotic disease, primarily circulates within rodent populations and their fleas. In Iran, the widely distributed jird, Meriones persicus, serves as the principal reservoir for plague, with a belief in the existence of five out of its six recognized subspecies within the country. However, these subspecies are classified into four mitochondrial cytochrome b sub-lineages (IA, IB, IIA, IIB). This discrepancy, combined with the presence of an unnamed sub-lineage in central Iran awaiting taxonomic clarification, has left intraspecific taxonomy unsettled and obscured the true alignment between mtDNA sub-lineages and nominal subspecies. In this study, we investigated the intraspecific variation in the cytb gene across populations sampled throughout Iran, focusing on underexplored regions between the Zagros and Alborz Mountains and central Iran. While our genetic data generally support reported subspecies validity in Iran, we raise questions about M. p. baptistae, emphasizing the need for further data from its type territory in Pakistan. Two main lineages of M. persicus (I and II) exhibit geographical isolation, with limited overlap in the central Zagros Mts., where three subspecies (M. p. ambrosius, M. p. rossicus, and M. p. persicus) coexist. Superimposing infected rodents' geographic coordinates onto updated sub-lineages' distribution revealed a potential association between sub-lineage IA (M. p. rossicus) and all enzootic plague cases from 1946 to 2023. M. persicus rossicus extends into the Caucasus (where plague infections are common), Eastern Turkey, and Iraq. Consequently, interpreting this finding in the context of plague surveillance in Iran and neighboring areas requires caution.

Epidemiological Situation on Plague around the World. Forecast of Epizootic Activity of Natural Plague Foci in the Russian Federation for 2024

The aim of the review was to assess the epidemiological situation in natural plague foci in the Russian Federation, near and far abroad countries in 2023 and to forecast their epizootic activity for 2024. In 2023, cases of plague were registered in five countries worldwide: the Democratic Republic of the Congo (60 cases), the Republic of Madagascar (14), the United States of America (2), the People’s Republic of China (3), and Mongolia (5). A total of 84 cases of plague were recorded, of which 22 (26.2 %) were fatal. In the Russian Federation, in 2023, epidemic risks in epizootically active natural foci were significantly reduced due to the implementation of a set of preventive measures carried out by Rospotrebnadzor institutions, which was the guarantor of ensuring epidemiological well-being as regards plague. Plague epizootics were detected on the territory of two (Gorno-Altai high-mountain and Tuva mountain) out of 11 natural plague foci in the Russian Federation in 2023. Epizootics were reported on the territory of the Kosh-Agach district of the Altai Republic and the Mongun-Taiginsky kozhuun of the Tuva Republic. The total area of epizootics was 731.2 km2 (in 2022 – 248.3 km2). In total, 55 cultures of the antique biovar of the main subspecies Yersinia pestis pestis were isolated in 2023 (19 in 2022). The forecast for continuation of the tense epidemiological situation in the territory of the Altai and Tuva Republics in 2024 is substantiated. The trend of sustained growth in the epizootic potential of the East Caucasus high-mountain and Dagestan plain-piedmont plague foci is outlined. The prospects for introducing an automated electronic system for assessing the epidemic potential of natural plague foci into practice are explained.

A sporadic case of small ruminant plague in sheep: morphological and functional manifestation of cellular and humoral immunodeficiency

The threat of the spread of small ruminant plague to livestock in a number of countries makes the study of the mechanisms of development and prevention of this disease a priority area of research. Therefore, the purpose of the study was to investigate the changes in the blood system and organs of the immune system in small ruminant plague, which led to the development of immunodeficiency in the body of infected animals. Haematological and histological methods were used in the study. As a result of the work carried out, a decrease in the total number of leukocytes in the peripheral blood from 12.4 to 7.3×109/l was detected in 3 sheep that died from small ruminant plague. There was also a shift in the normal ratio of granulocytes to agranulocytes from 1:1 to 2.5:1 towards granulocytes, which was provoked by a sharp decrease in the number of lymphocytes from 49% to 25% in the leukocyte blood count. Such changes in the blood system were provoked by significant degenerative changes in the lymphoid tissue of immunocompetent organs – lymph nodes and spleen. Histological examination of the parenchyma of the above organs revealed atrophy of T- and B-dependent zones and apoptosis of lymphocytes. Taken together, these signs – haematological and histological – allow for the conclusion that both the humoral and cellular immune response systems in the body are reduced. In the affected areas of the lungs, an inflammatory reaction is observed with active migration of neutrophils and macrophages to the inflammation zone. But the active multiplication of the virus in the lung cells indicates a lack of immunity. Thus, the study revealed the mechanisms of the development of humoral and cellular immunodeficiency in small ruminant plague (SRP), which would allow developing more effective methods of combating this disease

Assessing the effectiveness of intervention to prevent plague through community and animal-based survey.

Bubonic plague, transmitted by infected flea bites, is the most common form of plague and, left untreated, can progress to the pneumonic form, which is highly contagious. Surveillance focusing on reservoir and vector is considered to be the main approach to prevent plague. Common rodent control methods include the use of rodenticide and snap traps but, in a plague context, the dispersal of fleas from killed animals may pose a serious health threat. Therefore, there is a need for strategies which address reservoir and vector control. The aim of this study was to assess the effects of combination of reservoir and vector control through community-based surveillance. Activities were implemented by local previously trained community agents in two active plague foci in Madagascar. Kartman bait stations containing rodenticide and insecticide were placed indoors while live traps were set outdoors. Small mammals were identified and killed with their fleas. Effectiveness of control measures was evaluated by comparison of plague incidence two years before and after intervention using data on reported human cases of plague from the Central Laboratory of Plague. A total of 4,302 small mammals were captured, with the predominance of the black rat Rattus rattus. Our results found a reduction in plague incidence in the treated site for at least two years after treatment. Community-based interventions played an important role in reducing contact between humans-rodents-fleas. Our study confirms the importance of animal surveillance during the low plague transmission season. The combination of reservoir and vector control with community involvement may be effective at reducing the risks of plague spillover to humans. The strategy of using Kartman bait stations indoors with live traps outdoors can be used to refine proactive plague prevention, however, due to the potential development of resistance to pesticides in flea and rat populations, overuse should be considered.

Plague Gives Surprises in the Second Decade of the Twenty-First Century.

From 2010 through 2019, the six leading countries by numbers of human plague cases reported to the WHO were, in order from highest to lowest, Madagascar, Congo, Uganda, Peru, Tanzania, and the United States. From these countries, there was a total of 4,547 cases, of whom 786 (17%) died. Top plague events were four outbreaks of primary pneumonic plague in Madagascar that affected 1,936 persons, including index cases, of whom 137 died. One of the outbreaks was caused by a streptomycin-resistant strain of Yersinia pestis. Person-to-person transmission occurred in a taxi, in households with family caregivers, at burial ceremonies and wakes for victims, and at a hospital where cases were treated. Unique clinical presentations in the United States included a dog owner who acquired pneumonic plague from his sick dog, a boy with septicemic plague who developed complications of osteomyelitis and arthritis that required surgery for bone removal and bone grafting, and a prairie dog handler who acquired bubonic plague from a bite by a sick prairie dog. Efficacy of antibiotics in a model of pneumonic plague in African green monkeys for use in bioterrorism revealed the most effective drugs to be gentamicin, ciprofloxacin, and levofloxacin. A recombinant vaccine containing Fraction 1 antigen and V antigen of Y. pestis designed for first responders during a bioterrorism attack and military personnel was tested for safety and immunogenicity but was not licensed for use by the end of the decade.

Socioenvironmental determinants as indicators of plague risk in the central highlands of Madagascar: Experience of Ambositra and Tsiroanomandidy districts.

Human plague cases are reported annually in the central highland regions of Madagascar, where the disease is endemic. The socioenvironmental characteristics and lifestyles of the populations of the central highland localities could be linked to this endemicity. The aim of this study was to determine socioenvironmental determinants that may be associated with plague risk and explain this variation in epidemiological contexts. The current study was based on the distribution of plague cases between 2006 and 2015 that occurred in localities of districts positioned in the central highlands. Household surveys were performed from June to August 2017 using a questionnaire and direct observations on the socioenvironmental aspects of households in selected localities. Bivariate and multivariate analyses were performed to highlight the socioenvironmental parameters associated with plague risk in both districts. A total of 503 households were surveyed, of which 54.9% (276/503) were in Ambositra and 45.1% (227/503) were in Tsiroanomandidy. Multivariate analyses showed that thatched roofs [adjusted odds ratio (AOR): 2.63; 95% confidence interval (95% CI): 1.78-3.88] and ground floor houses [AOR: 2.11; 95% CI: 1.3-3.45-] were significantly associated with the vulnerability of a household to plague risk (p value<0.05). Plague risk in two districts of the Malagasy central highlands is associated with human socioenvironmental characteristics. Socioenvironmental characteristics are parameters expressing spatial heterogeneity through the difference in epidemiological expression of the plague in Ambositra and Tsiroanomandidy. These characteristics could be used as indicators of vulnerability to plague risk in plague-endemic areas.

Plague: Symptoms, Transmission, Diagnosis, Prevention and Treatment

Plague is a contagious disease caused by the zoonotic bacteria, (Yersinia pestis) but transmitted by fleas. It is found on rodents and their fleas. The most common ways for humans to contract plague are through handling a plague-infected animal or by getting bitten by a rodent flea that is carrying the pathogen. Septicemic, pneumonic, and bubonic plague are the three most prevalent types. The bubonic plague typically takes 2 to 8 days to incubate. Patients experience weakness, one or more enlarged, painful lymph nodes, headache, chills, and fever (called buboes). The bite of an infected flea results in plague, which is the most widespread type of plague. Pneumonic plague, a more severe form of bubonic plague, can progress and disseminate to the lungs. Septicemic plague incubation period isn’t exactly known but, it most likely happens within days of exposure and is accompanied by high temperature, chills, intense exhaustion, stomach discomfort, shock, and maybe, bleeding into the skin and other organs. Pneumonic plague often only takes 1 to 3 days to incubate and is accompanied by a fever, headache, weakness, rapidly progressing pneumonia, shortness of breath, chest pain, coughing up occasionally bloody or watery mucus, and other symptoms. Generally, fever, chills, headaches, and nausea are some of the general plague symptoms. There is also the case of lymph nodes enlargement, coughing, chest pain, and hemoptysis. Plague can be transmitted through; bites by fleas, contact with contaminated fluid or tissue, and infectious droplets. The symptoms of plague are typically non-specific; hence laboratory investigation is necessary for a certain diagnosis. Y. pestis infection can be detected using a microscope and by bacteria culture. The sample (buboes) can be gotten from blood, mucus (sputum), or an aspirate taken from swollen lymph nodes. Polymerase chain reaction (PCR), can also be employed to diagnose plague (F1 capsule antigen). It is also possible to identify plague by using blood tests that look for antibodies to Y. pestis. Plague can be prevented by eliminating rodent’s habitats around living houses, workplace, and leisure locations, and elimination of bushes, rock piles, garbage, cluttered firewood, and potential rodent food sources such as pet and wild animal food. Plague vaccines are only recommended for high-risk categories such as laboratory professionals who are constantly exposed to the risk of contamination, and health care workers. All forms of plague respond to antibiotic treatment if they are diagnosed early. Those suspected to have made contact with infected patients or animals should be isolated and observed. Plague remains one of the most infectious diseases worldwide. Although as at the time of this review, there is no recent case of plague in Nigeria, or in Africa, effort is still required to create robust awareness among the population on the subject of plague. The focus of this review is to educate and create more awareness among the citizens on plague as a highly infectious disease.

Phylogenetic analysis of the origin and spread of plague in Madagascar

Plague is a zoonotic disease caused by the bacterium Yersinia pestis, highly prevalent in the Central Highlands, a mountainous region in the center of Madagascar. After a plague-free period of over 60 years in the northwestern coast city of Mahajanga, the disease reappeared in 1991 and caused several outbreaks until 1999. Previous research indicates that the disease was reintroduced to the city of Mahajanga from the Central Highlands instead of reemerging from a local reservoir. However, it is not clear how many reintroductions occurred and when they took place. In this study we applied a Bayesian phylogeographic model to detect and date migrations of Y. pestis between the two locations that could be linked to the re-emergence of plague in Mahajanga. Genome sequences of 300 Y. pestis strains sampled between 1964 and 2012 were analyzed. Four migrations from the Central Highlands to Mahajanga were detected. Two resulted in persistent transmission in humans, one was responsible for most of the human cases recorded between 1995 and 1999, while the other produced plague cases in 1991 and 1992. We dated the emergence of the Y. pestis sub-branch 1.ORI3, which is only present in Madagascar and Turkey, to the beginning of the 20th century, using a Bayesian molecular dating analysis. The split between 1.ORI3 and its ancestor lineage 1.ORI2 was dated to the second half of the 19th century. Our results indicate that two independent migrations from the Central Highlands caused the plague outbreaks in Mahajanga during the 1990s, with both introductions occurring during the early 1980s. They happened over a decade before the detection of human cases, thus the pathogen likely survived in wild reservoirs until the spillover to humans was possible. This study demonstrates the value of Bayesian phylogenetics in elucidating the re-emergence of infectious diseases.

Subtractive Genomics Based Analysis For In Silico Recognition And Characterization Of New Drug Targets In Yersinia Pestis

Yersinia pestis (Y. pestis) is a gram-negative bacteriam.it cause plague disease. Between 30% and 100% of untreated patients die, with pneumonic plague being the deadliest. Chloramphenicol Streptomycin and tetracycline are the three main antibiotics that are used for plague treatment. Even if antibiotics are given right away, 16% of people with bubonic plague and more than 50% of people with pneumonic plague die. The number of plague cases and epidemics over the past 15 years has increased to the point where the disease is now considered reemerging. Researchers have discovered that some strains of the plague are immune to the most effective medications now in use to treat the disease. Y. pestis is worrisome since there is no effective vaccination, it must be treated with antibiotics, and it has a history of being used as a bioweapon. Antibiotic-resistant bacteria are a worldwide problem. It has been revealed that two strains of Y. pestis are highly resistant to eight antimicrobial medicines used for cure. Additionally, it is resistant to a number of commonly used antibiotics, including ampicillin, kanamycin, and spectinomycin. In subtractive genomics approach the bacterial total proteome is gently nethermost to a few numbers of probable targets for drug. The steps which are applied in this method to detect targets proteins which are non-similar to human and are vital for bacteria and contribution of the sorted out proteins in bacterial pathways of metabolism that are vital for continuity of pathogen. In this study the approach of subtractive genomics is applied on proteins of Y. pestis and culminated with 4 proteins that may be powerful drug targets and novel zestful molecules can be designed against them to cure the bacteria associated infection.

International Cooperation of Kazakhstan in the Prevention of Particularly Dangerous Infections

The dependence of the incidence of various nosologies on the epidemic situation in neighboring countries has been a feature of the epidemic process in recent years. In this regard, it is of particular importance to carry out joint anti-epidemic and preventive measures in border areas in order to prevent the importation of dangerous infections into the territory of neighboring states. The aim of the work was to analyze the results of international cooperation in the prevention of particularly dangerous infections. Presented are the areas of cooperation and outcomes of joint research activities. Measures for cooperation between the relevant institutions of the Ministry of Health of the Republic of Kazakhstan and the Rospotrebnadzor on the operational exchange of information in case of emergencies, joint research work on the monitoring of particularly dangerous and other natural-focal infectious diseases in the border areas, joint seminars, scientific and practical conferences on the introduction of modern methods of laboratory diagnostics into practice, internships on the exchange of experience in epizootiological survey in foci of particularly dangerous infections are described in the paper. Examples of Russian-Kazakh cooperation are provided. The results of a joint epizootiological survey of the territory of the Kazakh part of the Altai Mountains are presented. On a global scale, cases of plague and other particularly dangerous infections in any geographic region can constitute international public health emergencies and this type of threat requires international cooperation.

English

Madagascar is the country that reports the most cases of plague in the world. This is an evaluation study of plague diagnosis over a 2-year period from January 2017 to December 2018. For all suspected plague cases, peripheral RDT (performed locally), central RDT (performed in the laboratory) and PCR were performed. Parameters of the diagnostic tests used, year of study, performance and study of concordance between tests were studied. 2981 cases were collected, 21.6% were confirmed, 28.4% probable and 50% suspected. The sensitivities of peripheral RDT, central RDT and PCR were 96.55, 100 and 97.41%, respectively; the specificities were 41.43, 51.17 and 89.24%. Cohen&#39;s kappa was 0.12 between peripheral RDT and culture; 0.17 between culture and central RDT and 0.64 between CRP and culture. For pneumonic plague (PP) patient samples, sensitivities were 80.00, 66.66 and 93.33%, Cohen&#39;s kappa was 0.017 between peripheral RDT and culture; 0.013 between central RDT and culture and 0.371 between PCR and culture; sensitivities of peripheral RDT and central RDT were 75.00 and 62.50% for 2017, respectively. The null hypothesis between diagnostic tests was rejected, discordance between tests was found. Sensitivity is lowered during lung sampling and during 2017. &nbsp; Key words: Plague, polymerase chain reaction, technology assessment.

Serological evidence of Yersinia pestis infection in rodents and carnivores in Northwestern Iran.

Plague may recur after several decades in its endemic regions; therefore, the continuous monitoring of wildlife is essential, even when no human cases are reported in the old foci. The present study was conducted to monitor rodents and their ectoparasites as well as carnivores to learn about the epidemiology of plague infection in an old focus of Iran. The present study was conducted from 2019 to 2020 in Takestan county of Qazvin Province in northwestern Iran. Rodents were caught using live traps, and their fleas were separated. Blood and spleen specimens were taken from the captured rodents. Serum samples were also collected from sheepdogs and wild carnivores. The collected samples were tested by culture, serology (ELISA), and molecular methods to detect Yersinia pestis infection. A total of 399 small mammals were caught, of which 68.6% were Meriones persicus. A total of 2438 fleas were collected from the rodents, 95.3% of which were Xenopsylla buxtoni. Overall, 23 out of 377 tested rodents (5.7%, CI 95%, 3.9-9.0) had IgG antibodies against the F1 antigen of Y. pestis, and all the positive samples belonged to M. persicus. Nine (4.8%) out of 186 collected sera from the sheepdogs' serum and one serum from the Canis aureus had specific IgG antibodies against the F1 antigen of Y. pestis. There were no positive cases of Y. pestis in the rodents and fleas based on the culture and real-time PCR. Serological evidence of Y. pestis circulation was observed in rodents and carnivores (sheepdogs and C. aureus). The presence of potential plague vectors and serological evidence of Y. pestis infection in the surveyed animals could probably raise the risk of infection and clinical cases of plague in the studied region. Training health personnel is therefore essential to encourage their detection of possible human cases of the disease.

TECHNOLOGIES OF THE PRODUCTION OF ORGANIC PORK (review)

Goal. To summarize the domestic and world experience of the organic pork production technology. Methods. General scientific methods (classification, typology) were used, a structural-systemic approach was applied, as well as a source analysis and synthesis. The results. The production of organic pork takes place according to three systems: open, closed and mixed ones. The open system of organic pork production involves housing animals year-round in light-type houses. Under such a system, animals have constant access to green fodder, turf, insects, and worms, they show better natural behavior, which overall has a positive effect on their health and well-being. The mixed system of organic pork production involves housing suckling sows in premises equipped with farrowing machines, followed by their transfer with piglets to light-type houses on pasture and feeding with concentrated, green and coarse fodder (straw, hay). In the cold period, the fattening young pigs are housed in a light-type premise, where the front side is covered with a metal mesh, and in the warm period, they are transferred to the houses on the pasture. A review of literature sources on pork production in organic pig farming highlighted a number of problematic issues that need to be resolved. Thus, the open and combined systems of organic pig breeding in Ukraine today, as a result of the epidemiological situation that arose as a result of cases of African plague, practically cannot be used, although there are prerequisites for their further development and they are waiting for the lifting of quarantine restrictions. The closed system of organic pork production, which involves housing animals year-round in premises on straw bedding with walking areas and feeding them with concentrated and partly rough forage (straw, hay), has much greater possibilities compared to open and combined systems. But it does not provide animals with green fodder and does not protect animals from infectious disease agents such as zoophilous flies, ticks, and birds. In addition, a closed system does not address the deep utilization and recycling of pig waste products. Therefore, there is a need to improve the closed system by expanding its functionality. In our opinion, a closed system should provide deep processing of pig waste products, their recycling and energy-saving, waste-free production of organic pork. Conclusions. The open system of organic pig breeding is practically impossible to use, although there are prerequisites for their further development when quarantine restrictions are lifted. The combined system of organic pig breeding makes it possible to obtain high productivity and quality products. With such a system, better preservation of suckling piglets is achieved, but it also does not ensure the biosecurity of animals. The closed system of organic pork production today has significantly greater opportunities compared to open and combined systems. But it does not provide animals with green fodder and does not protect animals from infectious disease agents such as zoophilous flies, ticks, and birds. In addition, the closed system does not solve the deep utilization and recycling of pig waste products. Key words: organic pig breeding, pigs, open system, closed system, mixed system, pork production.