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Epidemics Dec 2018From August to November 2017, Madagascar endured an outbreak of plague. A total of 2417 cases of plague were confirmed, causing a death toll of 209. Public health...
From August to November 2017, Madagascar endured an outbreak of plague. A total of 2417 cases of plague were confirmed, causing a death toll of 209. Public health intervention efforts were introduced and successfully stopped the epidemic at the end of November. The plague, however, is endemic in the region and occurs annually, posing the risk of future outbreaks. To understand the plague transmission, we collected real-time data from official reports, described the outbreak's characteristics, and estimated transmission parameters using statistical and mathematical models. The pneumonic plague epidemic curve exhibited multiple peaks, coinciding with sporadic introductions of new bubonic cases. Optimal climate conditions for rat flea to flourish were observed during the epidemic. Estimate of the plague basic reproduction number during the large wave of the epidemic was high, ranging from 5 to 7 depending on model assumptions. The incubation and infection periods for bubonic and pneumonic plague were 4.3 and 3.4 days and 3.8 and 2.9 days, respectively. Parameter estimation suggested that even with a small fraction of the population exposed to infected rat fleas (1/10,000) and a small probability of transition from a bubonic case to a secondary pneumonic case (3%), the high human-to-human transmission rate can still generate a large outbreak. Controlling rodent and fleas can prevent new index cases, but managing human-to-human transmission is key to prevent large-scale outbreaks.
Topics: Animals; Basic Reproduction Number; Epidemics; Humans; Madagascar; Models, Theoretical; Plague; Public Health; Rats; Risk; Siphonaptera; Yersinia pestis
PubMed: 29866421
DOI: 10.1016/j.epidem.2018.05.001 -
Current Biology : CB Mar 2023The historical epidemiology of plague is controversial due to the scarcity and ambiguity of available data. A common source of debate is the extent and pattern of plague...
The historical epidemiology of plague is controversial due to the scarcity and ambiguity of available data. A common source of debate is the extent and pattern of plague re-emergence and local continuity in Europe during the 14th-18th century CE. Despite having a uniquely long history of plague (∼5,000 years), Scandinavia is relatively underrepresented in the historical archives. To better understand the historical epidemiology and evolutionary history of plague in this region, we performed in-depth (n = 298) longitudinal screening (800 years) for the plague bacterium Yersinia pestis (Y. pestis) across 13 archaeological sites in Denmark from 1000 to 1800 CE. Our genomic and phylogenetic data captured the emergence, continuity, and evolution of Y. pestis in this region over a period of 300 years (14th-17th century CE), for which the plague-positivity rate was 8.3% (3.3%-14.3% by site). Our phylogenetic analysis revealed that the Danish Y. pestis sequences were interspersed with those from other European countries, rather than forming a single cluster, indicative of the generation, spread, and replacement of bacterial variants through communities rather than their long-term local persistence. These results provide an epidemiological link between Y. pestis and the unknown pestilence that afflicted medieval and early modern Europe. They also demonstrate how population-scale genomic evidence can be used to test hypotheses on disease mortality and epidemiology and help pave the way for the next generation of historical disease research.
Topics: Humans; Yersinia pestis; Plague; Phylogeny; Genome, Bacterial; Denmark
PubMed: 36841239
DOI: 10.1016/j.cub.2023.01.064 -
Current Opinion in Microbiology Jun 2012Yersinia pestis, the causative agent of plague, is unique among the enteric group of Gram-negative bacteria in relying on a blood-feeding insect for transmission. The... (Review)
Review
Yersinia pestis, the causative agent of plague, is unique among the enteric group of Gram-negative bacteria in relying on a blood-feeding insect for transmission. The Yersinia-flea interactions that enable plague transmission cycles have had profound historical consequences as manifested by human plague pandemics. The arthropod-borne transmission route was a radical ecologic change from the food-borne and water-borne transmission route of Yersinia pseudotuberculosis, from which Y. pestis diverged only within the last 20000 years. Thus, the interactions of Y. pestis with its flea vector that lead to colonization and successful transmission are the result of a recent evolutionary adaptation that required relatively few genetic changes. These changes from the Y. pseudotuberculosis progenitor included loss of insecticidal activity, increased resistance to antibacterial factors in the flea midgut, and extending Yersinia biofilm-forming ability to the flea host environment.
Topics: Animals; Biological Evolution; Host-Pathogen Interactions; Insect Vectors; Plague; Siphonaptera; Yersinia pestis
PubMed: 22406208
DOI: 10.1016/j.mib.2012.02.003 -
Gaceta Sanitaria 2023The word "epidemiology" was written for the first time in a report on the plague in Alghero in 1583. Although its etymology has it intricacy. For centuries it has been...
The word "epidemiology" was written for the first time in a report on the plague in Alghero in 1583. Although its etymology has it intricacy. For centuries it has been concerned with understanding and trying to control and prevent epidemics. During the cholera epidemic in London in 1848 the London Society of Epidemiology was formed, main instrument of public health since then. The increase in chronic diseases -supposedly no communicable- gave way to the epidemiology of black boxes and the predominance of risk factors. And later to an enormous methodological progress increasingly complex and intricate but professionally very appealing. So few epidemiologists have experience in field control of epidemics. Thus, perhaps it is convenient to return, although partially, to the origins. Looking at the future.
Topics: Humans; Epidemics; Plague; Public Health; Cholera; Risk Factors
PubMed: 36508988
DOI: 10.1016/j.gaceta.2022.102277 -
Journal of Infection in Developing... Sep 2011Yersinia pestis (Y. Pestis) is an infamous pathogen causing plague pandemics throughout history and is a selected agent of bioterrorism threatening public health. Y.... (Review)
Review
Yersinia pestis (Y. Pestis) is an infamous pathogen causing plague pandemics throughout history and is a selected agent of bioterrorism threatening public health. Y. pestis was first isolated by Alexandre Yersin in 1894 in Hong Kong and in the following years from all continents. Plague is enzootic in different rodents and their fleas in Africa, North and South America, and Asia, including the Middle/Far East and ex-USSR countries. Comprehending the multifaceted interaction between Y. pestis and the host immune system will enable us to design more effective vaccines. Innate immune response and both components (humoral and cellular) of adaptive immune response contribute to host defense against Y. pestis infection, but the bacterium possesses different mechanisms to counteract the immune response. The review aims to analyze the role of immune response versus Yersinia pestis infection and to highlight the various stratagems adopted by Y. pestis to escape the immunological defenses.
Topics: Adaptive Immunity; Animals; Antibodies, Bacterial; Bioterrorism; Humans; Immune Evasion; Immunity, Innate; Pandemics; Plague; Public Health; Yersinia pestis
PubMed: 21918303
DOI: 10.3855/jidc.1999 -
Scientific Reports Nov 2021The plague of 1630-1632 was one of the deadliest plague epidemics to ever hit Northern Italy, and for many of the affected regions, it was also the last. While accounts...
The plague of 1630-1632 was one of the deadliest plague epidemics to ever hit Northern Italy, and for many of the affected regions, it was also the last. While accounts on plague during the early 1630s in Florence and Milan are frequent, much less is known about the city of Imola. We analyzed the full skeletal assemblage of four mass graves (n = 133 individuals) at the Lazaretto dell'Osservanza, which date back to the outbreak of 1630-1632 in Imola and evaluated our results by integrating new archival sources. The skeletons showed little evidence of physical trauma and were covered by multiple layers of lime, which is characteristic for epidemic mass mortality sites. We screened 15 teeth for Yersinia pestis aDNA and were able to confirm the presence of plague in Imola via metagenomic analysis. Additionally, we studied a contemporaneous register, in which a friar recorded patient outcomes at the lazaretto during the last year of the epidemic. Our multidisciplinary approach combining historical, osteological and genomic data provided a unique opportunity to reconstruct an in-depth picture of the last plague of Imola through the city's main lazaretto.
Topics: Adult; Archaeology; Child; Child, Preschool; DNA, Ancient; DNA, Bacterial; Disease Outbreaks; Female; Geography, Medical; History, 17th Century; Humans; Italy; Male; Metagenome; Metagenomics; Plague; Yersinia pestis
PubMed: 34782694
DOI: 10.1038/s41598-021-98214-2 -
Biomolecules Feb 2021The ability to cause plague in mammals represents only half of the life history of . It is also able to colonize and produce a transmissible infection in the digestive... (Review)
Review
The ability to cause plague in mammals represents only half of the life history of . It is also able to colonize and produce a transmissible infection in the digestive tract of the flea, its insect host. Parallel to studies of the molecular mechanisms by which is able to overcome the immune response of its mammalian hosts, disseminate, and produce septicemia, studies of -flea interactions have led to the identification and characterization of important factors that lead to transmission by flea bite. adapts to the unique conditions in the flea gut by altering its metabolic physiology in ways that promote biofilm development, a common strategy by which bacteria cope with a nutrient-limited environment. Biofilm localization to the flea foregut disrupts normal fluid dynamics of blood feeding, resulting in regurgitative transmission. Many of the important genes, regulatory pathways, and molecules required for this process have been identified and are reviewed here.
Topics: Animals; Biofilms; Gastrointestinal Microbiome; Gene Expression Regulation; Gene Expression Regulation, Bacterial; Genomics; Hydrodynamics; Immune System; Insect Vectors; Plague; Signal Transduction; Siphonaptera; Yersinia pestis; Yersinia pseudotuberculosis
PubMed: 33546271
DOI: 10.3390/biom11020210 -
BMJ (Clinical Research Ed.) Oct 1994
Topics: Disease Outbreaks; Humans; India; Plague; Public Health; Travel
PubMed: 7950651
DOI: 10.1136/bmj.309.6959.893 -
American Journal of Public Health Mar 2021In this article, I explore the historical resonances between China's 1911 pneumonic plague and our current situation with COVID-19. At the turn of the 20th century,...
In this article, I explore the historical resonances between China's 1911 pneumonic plague and our current situation with COVID-19. At the turn of the 20th century, China was labeled "the Sick Man of the Far East": a once-powerful country that had become burdened by opium addiction, infectious disease, and an ineffective government. In 1911, this weakened China faced an outbreak of pneumonic plague in Manchuria that killed more than 60 000 people. After the 1911 plague, a revolutionized China radically restructured its approach to public health to eliminate the stigma of being "the Sick Man." Ironically, given the US mishandling of the COVID pandemic, observers in today's China are now calling the United States "the Sick Man of the West": a country burdened by opioid addiction, infectious disease, and an ineffective government. The historical significance of the phrase "Sick Man"-and its potential to now be associated with the United States-highlights the continued links between epidemic control and international status in a changing world. This historical comparison also reveals that plagues bring not only tragedy but also the opportunity for change.
Topics: COVID-19; China; Communicable Disease Control; Epidemics; History, 20th Century; History, 21st Century; Humans; Plague; Politics; SARS-CoV-2; United States
PubMed: 33476233
DOI: 10.2105/AJPH.2020.305960 -
Veterinary Research 2009Plague is a flea-borne zoonotic bacterial disease caused by Yersinia pestis. It has caused three historical pandemics, including the Black Death which killed nearly a... (Review)
Review
Plague is a flea-borne zoonotic bacterial disease caused by Yersinia pestis. It has caused three historical pandemics, including the Black Death which killed nearly a third of Europe's population in the 14th century. In modern times, plague epizootics can extirpate entire susceptible wildlife populations and then disappear for long time periods. Understanding how Y. pestis is maintained during inter-epizootic periods and the factors responsible for transitioning to epizootics is important for preventing and controlling pathogen transmission and ultimately reducing the burden of human disease. In this review, we focus primarily on plague in North American foci and discuss the potential adaptive strategies Y. pestis might employ to ensure not only its survival during inter-epizootic periods but also the rapid epizootic spread and invasion of new territories that are so characteristic of plague and have resulted in major pandemics and establishment of plague foci throughout much of the world.
Topics: Adaptation, Physiological; Animals; Disease Outbreaks; Humans; Plague; Siphonaptera; Yersinia pestis
PubMed: 18803931
DOI: 10.1051/vetres:2008039