The Black Death was the largest and deadliest pandemic of Yersinia pestis recorded in human history, and likely the most infamous individual pandemic ever documented. The plague originated in the Eurasian Steppes, before moving with Mongol hordes to the Black Sea, where it was then brought by Italian merchants to the Mediterranean. From here, the Black Death then spread to almost all corners of Europe, the Middle East, and North Africa. While it was never endemic to these regions, it was constantly re-introduced via trade routes from Asia (such as the Silk Road), and plague was present in Western Europe until the seventeenth century, and the other regions until the nineteenth century. Impact on Europe In Europe, the major port cities and metropolitan areas were hit the hardest. The plague spread through south-western Europe, following the arrival of Italian galleys in Sicily, Genoa, Venice, and Marseilles, at the beginning of 1347. It is claimed that Venice, Florence, and Siena lost up to two thirds of their total population during epidemic's peak, while London, which was hit in 1348, is said to have lost at least half of its population. The plague then made its way around the west of Europe, and arrived in Germany and Scandinavia in 1348, before travelling along the Baltic coast to Russia by 1351 (although data relating to the death tolls east of Germany is scarce). Some areas of Europe remained untouched by the plague for decades; for example, plague did not arrive in Iceland until 1402, however it swept across the island with devastating effect, causing the population to drop from 120,000 to 40,000 within two years. Reliability While the Black Death affected three continents, there is little recorded evidence of its impact outside of Southern or Western Europe. In Europe, however, many sources conflict and contrast with one another, often giving death tolls exceeding the estimated population at the time (such as London, where the death toll is said to be three times larger than the total population). Therefore, the precise death tolls remain uncertain, and any figures given should be treated tentatively.

Even in 2021, bubonic plague continues to exist in nature, and there are generally a few thousand human cases per year. Going back to the beginning of the 20th century, it is estimated that there were roughly one million cases per year in 1907. Within two decades, this number had fallen below one fifth of this level to 170,000 cases per year in the 1920s, and in the 1940s it was just over 20,000 per year. By the mid-20th century, it had fallen below 5,000 cases per year, but the rapid decrease in cases observed in the first half of the 1900s did not continue through the second half of the century. Even in 2019, there was one case of plague recorded in the United States. How infection occurs Yersinia pestis is the bacteria that causes the plague virus, and it is most commonly spread by rats and their fleas. The disease survives by fleas infecting rats, which in turn infect other fleas; the majority of rats survive the disease, which facilitates its spread; this is known as the "enzootic cycle ". Interestingly, the disease is usually fatal for the fleas, as it blocks their "stomachs" and causes them to starve; as the fleas get hungrier, they attempt to feed on more hosts, spreading the disease more rapidly. When the rats die, the parasitic fleas then search for a new host, which means that other animals (particularly mammals) are susceptible to this virus. While rat fleas can not survive on other hosts for very long, they can infect other (including human) fleas with the virus. The most common way for humans to contract the plague however, is when a rat flea bites its human host; during this process the flea simultaneously regurgitates Yersinia pestis bacteria into the wound, and this causes bubonic plague. Humans can then spread the disease among one another by coming into contact with the infected tissue or fluids of an infected person, or from the transfer of fleas. Continued existence of the plague Plague is extremely difficult to eradicate in nature, as rodent communities in the wild provide natural reservoirs for the disease to spread. In previous centuries, rats had much more frequent contact with humans for a variety of reasons; houses were more often made of wood (which made infestations easier), public spaces were much dirtier, and the presence of rats was tolerated more. As the understanding of epidemiology grew in the 20th century, this greatly reduced the frequency of plague in human populations. Unlike human diseases such as smallpox, which was eradicated through vaccination and other medical advancements, basic sanitation and the extermination of rats have been the driving force behind the decline of plague.

The Black Death, possibly the deadliest and most well-known pandemic in human history, arrived in Europe from the Eurasian Steppes in 1347 and killed as much as 60 percent of the population within the next five years. While this outbreak eventually subsided, it was just the beginning of the Second Plague Pandemic; the bubonic plague was never really endemic to Europe, but was continuously re-introduced to Europe and the Mediterranean region via trade from Asia. Plague in the interim Following the Black Death, outbreaks of plague were sporadic, and varied in severity; however the lack of understanding and treatment meant that these outbreaks had incredibly high fatality rates and often decimated large portions of infected populations. For example, London lost up to one quarter of its population to plague epidemics in the 1560s, and again in the 1660s, while more than a century later Moscow and the surrounding region reportedly lost several hundred thousand people to plague within two years. Smaller and more isolated communities, such as in Cyprus, Iceland, and Malta were hit infrequently but severely; Iceland reportedly lost two thirds of its total population in a single pandemic in the early 1400s. Decline in Europe Over four centuries after its arrival in Europe, epidemics began to wean on larger scales. Ireland recorded its final epidemic in 1650, and the trend then continued across the states of mainland Europe in the next few decades. After plague disappeared from the German states in the 1680s, there were no more plague epidemics recorded in North or Western Europe. Despite this, it would be almost 160 years before plague disappeared from the Balkans and Turkey. As of 1841, the only part of Europe where plague was still endemic was along the Volga river in Russia; it was brought there by fisherman to the Caspian Sea from Persia and the Eurasian Steppe region.

Plague data for the Black Death.

Bubonic plague was a constant threat to Afro-Eurasian populations during the Second Plague pandemic. This pandemic arrived in Europe as the Black death in 1347, and although it never became endemic, it was constantly re-introduced to the continent over the next four centuries. By the late seventeenth century, most regions of Europe had recorded their final epidemics (but not necessarily the final cases), and it eventually subsided in the mid-nineteenth century. The death tolls due to plague were relatively low in most years, however, when epidemics appeared they could often decimate populations within a few short years, and lead to mass evacuations of major cities (such as in London in 1665). Plague in Russia Of the sample epidemics shown here, the two largest cases were in Russia; a region where plague outbreaks were much more frequent than in other parts of Europe. The reason for this was because plague would spread along the Volga river, after being brought to the Caspian Sea by fishermen from the Eurasian Steppes (where the plague bacteria Yersinia pestis is thought to originate). Between these two epidemics, it is estimated that Russia lost over half a million people. The epidemic of 1709, which spread across Northern Europe during the Great Northern War, saw a reported 150,000 deaths across the Russian Empire. The plague epidemic of 1771 in Russia saw the deaths of approximately 60,000 in the capital city, and as many as 300,000 in the surrounding region. In Moscow, the government's attempts to contain the outbreak resulted in a riot by the citizens, and the aftermath saw significant socio-political upheaval in the city and beyond.

Legend: Year: the demography of the 6 "years of plague" is in bold characters and the column immediately at the left indicates, for each epidemic, the demography of the previous year. Mortality rate: crude mortality rate (as per thousand) evaluated for the heads of households; reflects the global damage of an epidemic S1 Fig. Survivors: number of surviving heads of households after exclusion of those not corresponding to individuals S2 Text. Single deaths: number of households with one reported death, whether or not of the head of household. Multiple deaths: number of deaths in the households where the concomitant death of several persons is reported S4 Text. Total deaths: total number of deaths taken into account for analysis (sum of lines 4 and 5). Death rate: ratio between the number of reported deaths and the sum of reported deaths and survivors (as percent); does not reflect the mortality of the year, but allows comparisons between groups of individuals or areas during the same year. Grouped deaths: households where multiple deaths took place, or households contiguous or separated by a single survivor in the register.Demography of the "years of plague" and of the previous years.

95% equal-tailed credible intervals for the Black Death plague data from Table 2 for various priors.

Although the Black Death peaked in Europe between 1348 and 1351, plague was almost always present in Britain for the next four centuries. In most years, plague was a dormant threat that affected very few people, and diseases such as smallpox and influenza were much more widespread; however, bubonic plague was prone to outbreaks that could decimate populations in a few short years. In London, plague outbreaks occurred every few decades, usually with death tolls in the tens of thousands. The duration and severity of these epidemics varied, sometimes having high death tolls but subsiding quickly, while others had relatively lower death tolls but could last for a number of years. As London's population and density also grew drastically during this period, plague affected the city differently in the sixteenth and seventeenth centuries. Great Plague of London The final major plague epidemic observed in Britain took place in 1665 and 1666. It became known as the "Great Plague" as it was the last of its kind in Britain, and its death toll eclipsed all other epidemics in the preceding century (although it was much smaller than that of the Black Death). The plague lasted for eighteen months, and had a reported death toll of more than 70,000 in this time; although modern historians estimate that the actual death toll exceeded 100,000. At its peak in September 1665, it is reported that there were more than 7,000 deaths per week, although this may have also been much higher due to the limited records kept at the time. Another reason for the lack of accurate records relating to this epidemic is because of the Great Fire of London in 1666. The fire started on September 02. 1666, and destroyed almost all of the city within the walls, leaving thousands homeless. Historians continue to debate the fire's significance, some citing that it destroyed the unsanitary dwellings where infected rats lived and drove them from the city, while others claim that the timings were purely coincidental and that the epidemic had already begun to subside in February.

For most years between 1603 and 1680, plague was responsible for less than one percent of all deaths in London. However, when epidemics did break out they could often be responsible for more than half of all deaths in the city during those years, even going as high as 86 percent in 1603. This was the highest share of deaths due to plague in London in the given time period, although the final epidemic shown in the graph is remembered as the most devastating, taking almost 70,000 lives during the Great Plague of London in 1665.

Graph and download economic data for Age-Adjusted Premature Death Rate for Black Hawk County, IA (CDC20N2UAA019013) from 1999 to 2020 about Black Hawk County, IA; Waterloo; premature; death; IA; rate; and USA.

Premature Death Rate for Black Hawk County, IA was 535.70000 Rate per 100,000 in January of 2020, according to the United States Federal Reserve. Historically, Premature Death Rate for Black Hawk County, IA reached a record high of 535.70000 in January of 2020 and a record low of 323.10000 in January of 2007. Trading Economics provides the current actual value, an historical data chart and related indicators for Premature Death Rate for Black Hawk County, IA - last updated from the United States Federal Reserve on September of 2025.

Site codes and contexts for all individuals included in the study. All individuals are curated at the Museum of London Centre for Human Bioarchaeology. (DOCX)

Age-Adjusted Premature Death Rate for Black Hawk County, IA was 422.70000 Rate per 100,000 in January of 2020, according to the United States Federal Reserve. Historically, Age-Adjusted Premature Death Rate for Black Hawk County, IA reached a record high of 422.70000 in January of 2020 and a record low of 312.50000 in January of 2007. Trading Economics provides the current actual value, an historical data chart and related indicators for Age-Adjusted Premature Death Rate for Black Hawk County, IA - last updated from the United States Federal Reserve on July of 2025.

This dataset of U.S. mortality trends since 1900 highlights the differences in age-adjusted death rates and life expectancy at birth by race and sex. Age-adjusted death rates (deaths per 100,000) after 1998 are calculated based on the 2000 U.S. standard population. Populations used for computing death rates for 2011–2017 are postcensal estimates based on the 2010 census, estimated as of July 1, 2010. Rates for census years are based on populations enumerated in the corresponding censuses. Rates for noncensus years between 2000 and 2010 are revised using updated intercensal population estimates and may differ from rates previously published. Data on age-adjusted death rates prior to 1999 are taken from historical data (see References below). Life expectancy data are available up to 2017. Due to changes in categories of race used in publications, data are not available for the black population consistently before 1968, and not at all before 1960. More information on historical data on age-adjusted death rates is available at https://www.cdc.gov/nchs/nvss/mortality/hist293.htm. SOURCES CDC/NCHS, National Vital Statistics System, historical data, 1900-1998 (see https://www.cdc.gov/nchs/nvss/mortality_historical_data.htm); CDC/NCHS, National Vital Statistics System, mortality data (see http://www.cdc.gov/nchs/deaths.htm); and CDC WONDER (see http://wonder.cdc.gov). REFERENCES National Center for Health Statistics, Data Warehouse. Comparability of cause-of-death between ICD revisions. 2008. Available from: http://www.cdc.gov/nchs/nvss/mortality/comparability_icd.htm. National Center for Health Statistics. Vital statistics data available. Mortality multiple cause files. Hyattsville, MD: National Center for Health Statistics. Available from: https://www.cdc.gov/nchs/data_access/vitalstatsonline.htm. Kochanek KD, Murphy SL, Xu JQ, Arias E. Deaths: Final data for 2017. National Vital Statistics Reports; vol 68 no 9. Hyattsville, MD: National Center for Health Statistics. 2019. Available from: https://www.cdc.gov/nchs/data/nvsr/nvsr68/nvsr68_09-508.pdf. Arias E, Xu JQ. United States life tables, 2017. National Vital Statistics Reports; vol 68 no 7. Hyattsville, MD: National Center for Health Statistics. 2019. Available from: https://www.cdc.gov/nchs/data/nvsr/nvsr68/nvsr68_07-508.pdf. National Center for Health Statistics. Historical Data, 1900-1998. 2009. Available from: https://www.cdc.gov/nchs/nvss/mortality_historical_data.htm.

Plague data for pestis secunda.

Statistical table of the number of cases by region, age group, and gender since 2003 (Disease name: plague, date type: onset date, case type: confirmed case, source of infection: domestic, imported)

Legend: Line 1: Grouped death clusters (and Dijon). Line 2: total number of households (deaths and survivors). Line 3: number of deaths (grouped and non-grouped). Line 4: result of the chi-square comparing the cluster to the rest of the city. Line 5: death rate as percent. Column 2: pooled data from the 3 clusters of higher grouped death relative risk. Column 3: data restricted to the larger cluster of higher grouped death relative risk (included in the previous column). Column 4: pooled data from the 2 clusters of lower grouped death relative risk. Column 5: data for the whole city. For each cluster, data of the control (rest of the city) can be computed by subtraction from the data of the whole city.Deaths in the mortality-based clusters in 1400.

The leading causes of death in Massachusetts are cancer, heart disease, unintentional injury, stroke, and chronic lower respiratory disease. These mortality rates tend to be higher for people of color; and Black residents have a higher premature mortality rate overall and Asian residents have a higher rate of mortality due to stroke.

Note: DPH is updating and streamlining the COVID-19 cases, deaths, and testing data. As of 6/27/2022, the data will be published in four tables instead of twelve. The COVID-19 Cases, Deaths, and Tests by Day dataset contains cases and test data by date of sample submission. The death data are by date of death. This dataset is updated daily and contains information back to the beginning of the pandemic. The data can be found at https://data.ct.gov/Health-and-Human-Services/COVID-19-Cases-Deaths-and-Tests-by-Day/g9vi-2ahj. The COVID-19 State Metrics dataset contains over 93 columns of data. This dataset is updated daily and currently contains information starting June 21, 2022 to the present. The data can be found at https://data.ct.gov/Health-and-Human-Services/COVID-19-State-Level-Data/qmgw-5kp6 . The COVID-19 County Metrics dataset contains 25 columns of data. This dataset is updated daily and currently contains information starting June 16, 2022 to the present. The data can be found at https://data.ct.gov/Health-and-Human-Services/COVID-19-County-Level-Data/ujiq-dy22 . The COVID-19 Town Metrics dataset contains 16 columns of data. This dataset is updated daily and currently contains information starting June 16, 2022 to the present. The data can be found at https://data.ct.gov/Health-and-Human-Services/COVID-19-Town-Level-Data/icxw-cada . To protect confidentiality, if a town has fewer than 5 cases or positive NAAT tests over the past 7 days, those data will be suppressed. COVID-19 cases and associated deaths that have been reported among Connecticut residents, broken down by race and ethnicity. All data in this report are preliminary; data for previous dates will be updated as new reports are received and data errors are corrected. Deaths reported to the either the Office of the Chief Medical Examiner (OCME) or Department of Public Health (DPH) are included in the COVID-19 update. The following data show the number of COVID-19 cases and associated deaths per 100,000 population by race and ethnicity. Crude rates represent the total cases or deaths per 100,000 people. Age-adjusted rates consider the age of the person at diagnosis or death when estimating the rate and use a standardized population to provide a fair comparison between population groups with different age distributions. Age-adjustment is important in Connecticut as the median age of among the non-Hispanic white population is 47 years, whereas it is 34 years among non-Hispanic blacks, and 29 years among Hispanics. Because most non-Hispanic white residents who died were over 75 years of age, the age-adjusted rates are lower than the unadjusted rates. In contrast, Hispanic residents who died tend to be younger than 75 years of age which results in higher age-adjusted rates. The population data used to calculate rates is based on the CT DPH population statistics for 2019, which is available online here: https://portal.ct.gov/DPH/Health-Information-Systems--Reporting/Population/Population-Statistics. Prior to 5/10/2021, the population estimates from 2018 were used. Rates are standardized to the 2000 US Millions Standard population (data available here: https://seer.cancer.gov/stdpopulations/). Standardization was done using 19 age groups (0, 1-4, 5-9, 10-14, ..., 80-84, 85 years and older). More information about direct standardization for age adjustment is available here: https://www.cdc.gov/nchs/data/statnt/statnt06rv.pdf Categories are mutually exclusive. The category “multiracial” includes people who answered ‘yes’ to more than one race category. Counts may not add up to total case counts as data on race and ethnicity may be missing. Age adjusted rates calculated only for groups with more than 20 deaths. Abbreviation: NH=Non-Hispanic. Data on Connecticut deaths were obtained from the Connecticut Deaths Registry maintained by the DPH Office of Vital Records. Cause of death was determined by a death certifier (e.g., physician, APRN, medical

As of March 2, 2021, the states with the greatest COVID-19 mortality rates among Black residents were New York and New Jersey. This statistic shows the COVID-19 death rate per 100,000 population for Black U.S. residents as of March 2, 2021, by state.