History and future of pandemics / Historia y futuro de las pandemias

Este artículo presenta una historia general de las epidemias históricas y de las nuevas enfermedades emergentes, señalando sus factores desencadenantes. Se afirma que las epidemias son inevitables, y que su riesgo aumenta en proporción al tamaño, la complejidad y el poder tecnológico de nuestras sociedades. La historia enseña que las epidemias han sido casi siempre desencadenadas por cambios en el ambiente ocasionados por las propias actividades humanas. Las enfermedades infecciosas son manifestación de una interacción ecológica entre la especie humana y otra especie de microorganismos. Y las epidemias son resultado del cambio en algún factor ambiental capaz de influir en esa interacción. Las catástrofes epidémicas son inevitables: en primer lugar, porque no podemos evitar formar parte de cadenas tróficas en las que comemos y somos comidos por los microbios; en segundo lugar, porque las infecciones son mecanismos evolutivos y factores reguladores del equilibrio ecológico, que regulan sobre todo el tamaño de las poblaciones; y, en tercer lugar, porque las intervenciones técnicas humanas, al modificar los equilibrios previos, crean equilibrios nuevos que son más vulnerables. De este modo las sociedades humanas son más vulnerables cuanto más complejas. Y los éxitos humanos en la modificación de condiciones ambientales conservan, o más bien aumentan, el riesgo de catástrofes epidémicas. Todas las necesarias medidas de vigilancia y control epidemiológico imaginables pueden disminuir los daños que producen las epidemias, pero nunca podrán evitarlas.

This article presents a general history of historical epidemics, and new emerging diseases, pointing out their triggers. It is claimed that epidemics are inevitable, and that their risk increases in proportion to the size, complexity, and technological power of our societies. History teaches that epidemics have almost always been triggered by changes in the environment caused by human activities themselves. Infectious diseases are manifestations of an ecological interaction between the human species and another species of microorganisms. And epidemics are the result of a change in some environmental factor capable of influencing that interaction. Epidemic catastrophes are inevitable: firstly, because we cannot help but be part of trophic chains in which we eat and are eaten by microbes; secondly, because infections are evolutionary mechanisms and regulatory factors of ecological balance, which regulate especially the size of populations; and thirdly, because human technical interventions, in changing previous balances, create new balances that are more vulnerable. In this way human societies are more vulnerable the more complex. And human successes in modifying environmental conditions retain, or rather increase, the risk of epidemic catastrophes. All necessary epidemiological surveillance and control measures imaginable can lessen the damage caused by epidemics, but they can never prevent them.

Pandemics: past, present, future: That is like choosing between cholera and plague.

The major epidemic and pandemic diseases that have bothered humans since the Neolithic Age and Bronze Age are surveyed. Many of these pandemics are zoonotic infections, and the mathematical modeling of such infections is illustrated. Plague, cholera, syphilis, influenza, SARS, MERS, COVID-19, and new potential epidemic and pandemic infections and their consequences are described and the background for the spread of acute and chronic infections and the transition to endemic infections is discussed. The way we can prevent and fight pandemics is illustrated from the old and new well-known pandemics. Surprisingly, the political reactions through different periods have not changed much during the centuries.

Protection against severe infectious disease in the past.

Before the 20th century many deaths in England, and most likely a majority, were caused by infectious diseases. The focus here is on the biggest killers, plague, typhus, smallpox, tuberculosis, cholera, typhoid, dysentery, childhood infections, pneumonia, and influenza. Many other infectious diseases including puerperal fever, relapsing fever, malaria, syphilis, meningitis, tetanus and gangrene caused thousands of deaths. This review of preventive measures, public health interventions and changes in behavior that reduced the risk of severe infections puts the response to recent epidemic challenges in historical perspective. Two new respiratory viruses have recently caused pandemics: an H1N1 influenza virus genetically related to pig viruses, and a bat-derived coronavirus causing COVID-19. Studies of infectious diseases emerging in human populations in recent decades indicate that the majority were zoonotic, and many of the causal pathogens had a wildlife origin. As hunter-gatherers, humans contracted pathogens from other species, and then from domesticated animals and rodents when they began to live in settled communities based on agriculture. In the modern world of large inter-connected urban populations and rapid transport, the risk of global transmission of new infectious diseases is high. Past and recent experience indicates that surveillance, prevention and control of infectious diseases are critical for global health. Effective interventions are required to control activities that risk dangerous pathogens transferring to humans from wild animals and those reared for food.

Are we Athens or Florence? COVID-19 in historical context.

We have been here before. In 430 BCE, a plague struck Athens, killing as much as 25% of the population. In 1347 CE, the bubonic plague afflicted western Europe for 4 years, killing as much as 50% of the population. The plague of Athens led to a collapse of their religion, cultural norms and democracy. In contrast, the bubonic plague led eventually to the Renaissance, a growth of art, science and humanism. As we contend with the COVID-19 global pandemic, will we become Athens or Florence?

Traditional Chinese medicine combined with pulmonary drug delivery system and idiopathic pulmonary fibrosis: Rationale and therapeutic potential.

Idiopathic pulmonary fibrosis (IPF) is a progressive pulmonary interstitial inflammatory disease of unknown etiology, and is also a sequela in severe patients with the Coronavirus Disease 2019 (COVID-19). Nintedanib and pirfenidone are the only two known drugs which are conditionally recommended for the treatment of IPF by the FDA. However, these drugs pose some adverse side effects such as nausea and diarrhoea during clinical applications. Therefore, it is of great value and significance to identify effective and safe therapeutic drugs to solve the clinical problems associated with intake of western medicine. As a unique medical treatment, Traditional Chinese Medicine (TCM) has gradually exerted its advantages in the treatment of IPF worldwide through a multi-level and multi-target approach. Further, to overcome the current clinical problems of oral and injectable intakes of TCM, pulmonary drug delivery system (PDDS) could be designed to reduce the systemic metabolism and adverse reactions of the drug and to improve the bioavailability of drugs. Through PubMed, Google Scholar, Web of Science, and CNKI, we retrieved articles published in related fields in recent years, and this paper has summarized twenty-seven Chinese compound prescriptions, ten single TCM, and ten active ingredients for effective prevention and treatment of IPF. We also introduce three kinds of inhaling PDDS, which supports further research of TCM combined with PDDS to treat IPF.

Control measures of a 400-year-old plague epidemic: an example of past efficiency at controlling disease and similarities with current epidemics.

The plague caused by the bacterium Yersinia pestis, provides one of the best historical examples of pandemic infection. It can therefore be considered the first "globalized" disease, thanks also to the crowds that favoured the rebalancing of infectious agents between Europe and the Middle East. In this paper we analyse all the official documents of the time, highlighting the most effective prevention measures implemented in the city of Ferrara during the Italian plague. Historical mortality data for the 1630 Italian plague in northern Italy are first analysed. In contrast to the high rates recorded throughout the area from Milan to Florence, the mortality rate in Ferrara remained normal over the period. From the city's documents it emerged that the authorities, from the 16th century onwards, had already understood that the spread of the contagion could also occur through domestic animals, although rats are never mentioned. The strength of Ferrara's response to the "plague emergency" stems from an efficient and emergency-ready health control system, financed and supported by the "permanent surveillance team of the city and the Pontifical Legation of Ferrara - Azienda Sanitaria Pubblica" even in times of great economic difficulty for the State. Among the various measures that the city of Ferrara adopted to deal with the plague the following should be mentioned: guards at the city gates, lazarettos, safety of doctors, self-isolation and treatment of every suspicious case as if it were a real case of plague, measures to support the poorer classes of the population, veterinary and hygiene standards for the city and for housing, management of Catholic religious functions and the precepts of the Legation of Ferrara, which was under papal control, closure of churches to avoid mass gatherings, and limitations of all kinds of social and economic relations within and outside the population. The broad regimen, laid down in the 16th century, contains extremely modern health rules which are very much in line with those recommended by the WHO and the health authorities of each individual state in the current COVID-19 pandemic, even starting with hand-washing. The fight against epidemics of the past, especially the history of the plague in the 17th century, anticipates very important and valid concepts, and represents a wake-up call for the recent epidemics of emerging pathogens.

Historical Discoveries on Viruses in the Environment and Their Impact on Public Health.

BACKGROUND: Transmission of many viruses occurs by direct transmission during a close contact between two hosts, or by an indirect transmission through the environment. Several and often interconnected factors, both abiotic and biotic, determine the persistence of these viruses released in the environment, which can last from a few seconds to several years. Moreover, viruses in the environment are able to travel short to very long distances, especially in the air or in water. SUMMARY: Although well described now, the role of these environments as intermediaries or as reservoirs in virus transmission has been extensively studied and debated in the last century. The majority of these discoveries, such as the pioneer work on bacteria transmission, the progressive discoveries of viruses, as well as the persistence of the influenza virus in the air varying along with droplet sizes, or the role of water in the transmission of poliovirus, have contributed to the improvement of public health. Recent outbreaks of human coronavirus, influenza virus, and Ebola virus have also demonstrated the contemporaneity of these research studies and the need to study virus persistence in the environment. Key Messages: In this review, we discuss historical discoveries that contributed to describe biotic and abiotic factors determining viral persistence in the environment.

Quarantine as a tool of epidemic fight.

Until the 19th century, the factor causing epidemics was not known, and the escape from a place where it occurred as well as isolation of patients was considered to be the only effective way to avoid illness and death. Quarantine in a sense similar to modern times was used in 1377 in Ragusa, today's Dubrovnik, during the plague epidemic. It was the first administratively imposed procedure in the world's history. It was later used in Venice and other rich port cities in the Mediterranean. On the territory of today's Poland, quarantine measures were used by the so-called Mayor of the Air - LukaszDrewno in 1623 during the plague epidemic in Warsaw. The quarantine left its mark on all areas of human activity. It affected all humanity in a way that is underestimated today. Throughout history, it has been described and presented visually. It is omnipresent in the world literature, art and philosophy. However, the isolation and closure of cities, limiting trade, had an impact on the economic balance, and the dilemma between the choice of inhabitants' health and the quality of existence, i.e. their wealth, has been the subject of discussions since the Middle Ages. Since the end of the 19th century, quarantine has lost its practical meaning. The discovery of bacteria and a huge development of medical and social sciences allowed limiting its range. In the 20th century isolation and quarantine no longer had a global range, because the ability to identify factors causing the epidemic, knowledge about the incubation period, carrier, infectiousness, enabled the rational determination of its duration and territorial range. The modern SARS COV 2 pandemic has resulted in a global quarantine on a scale unprecedented for at least three hundred years. The aim of this paper is to present the history of quarantine from its beginning to the present day, including its usefulness as an epidemiological tool.

Acceleration of plague outbreaks in the second pandemic.

Historical records reveal the temporal patterns of a sequence of plague epidemics in London, United Kingdom, from the 14th to 17th centuries. Analysis of these records shows that later epidemics spread significantly faster ("accelerated"). Between the Black Death of 1348 and the later epidemics that culminated with the Great Plague of 1665, we estimate that the epidemic growth rate increased fourfold. Currently available data do not provide enough information to infer the mode of plague transmission in any given epidemic; nevertheless, order-of-magnitude estimates of epidemic parameters suggest that the observed slow growth rates in the 14th century are inconsistent with direct (pneumonic) transmission. We discuss the potential roles of demographic and ecological factors, such as climate change or human or rat population density, in driving the observed acceleration.