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The cholera epidemic that hit Haiti from October 2010 to February 2019 was the world's deadliest of the last 25 years. Officially, the successive waves caused 9789 deaths, although numerous additional casualties could not be recorded. The origin of this epidemic has been the subject of a controversy involving two opposing theories. The first hypothesis, put forward by renowned American academics, was that the cholera epidemic originated from the environment, due to the proliferation and transmission of aquatic Vibrio cholerae bacteria driven by a confluence of circumstances, i.e., the earthquake followed by a hot summer and, ultimately, heavy rainfall and flooding. The alternative hypothesis, which was subsequently confirmed by epidemiological and genomic studies, attributed the epidemic to the recent importation of cholera by UN peacekeepers recently arrived from Nepal, and to a river polluted with sewage. In late 2016, the Secretary General of the United Nations finally begged the Haitian people for forgiveness. This implicit recognition of the role of the UN in the cholera epidemic helped to fund the ongoing fight against it. Case-area targeted interventions aimed at interrupting cholera transmission were reinforced, which resulted in the extinction of the epidemic within two years. In the meantime, several phylogenetic studies on Vibrio cholerae during the seventh cholera pandemic demonstrated that local environmental and global epidemic Vibrio populations were distinct. These studies also showed that epidemics arose when the bacterium had diversified and that it had spread during transmission events associated with human travel.

The Covid-19 pandemic appeared in China in December 2019 as a cluster of transmissible pneumonia caused by a new betacoronavirus. On March 11, 2020, the World Health Organization (WHO) declared it a pandemic. Covid-19 is a mild infection in 80% of cases, serious in 15% and critical in 5%. Symptomatic forms include a first phase of flu-like viral invasion, and at times a second phase, dysimmune and inflammatory, with acute respiratory distress syndrome, multiorgan failure and thromboembolic complications. Degree of severity is related to age and comorbidities.

SARS-CoV-2 is the third highly pathogenic Betacoronavirus to cross the species barrier. Its genome, an RNA of 29,903 nucleotides, shows strong homogeneity with bat coronaviruses from southern China, but the conditions for its passage in humans have yet to be elucidated. Mutations can give rise to variants of concern (VOC) that are more transmissible and able to evade the host's immune response. Several VOCs have succeeded and replaced one another: Alpha in October 2020, Beta and Gamma in December 2020, Delta in spring 2021 and Omicron in November 2021. The Covid-19 pandemic has evolved in five waves of unequal amplitude and severity, with geographical disparities. Worldwide, it has caused 395,000,000 confirmed cases including 5,700,000 deaths.

Epidemiological surveillance applies several indicators (incidence rate, test positivity rate, effective R and occupancy rate of intensive care beds) supplemented by genomic monitoring to detect variants by sequencing.

Non-pharmacological measures, particularly face mask wearing, have been effective in preventing the transmission of SARS-CoV-2. Few currently available drugs have proven useful, with the exception of dexamethazone for patients requiring oxygen therapy. Development of SARS-CoV-2 vaccines began early on many platforms. Innovation was brought about by the Pfizer-BioNTech and Moderna messenger RNA vaccines, which claim protective efficacy of 95% and 94.1% respectively, far higher than the 70% minimum set by the WHO.

Governments have hesitated between two strategies, mitigation and suppression. The second has been favored in critical periods such as April 2020, when 2.5 billion people throughout the world were confined. Vaccination campaigns got underway at the end of December 2020 and progressed without reaching sufficient herd immunity, leading some nations to consider compulsory vaccination or to require a vaccine or health pass, in order for persons to access different activities.

Will the pandemic stop with Omicron and become endemic? This part of the Covid-19 story remains to be told.

The “Russian flu”, which raged from 1889 to 1894, is considered as the first pandemic of the industrial era for which statistics have been collected. This planetary event started in Turkestan and hit the Russian Empire, before reaching all European countries, the United States of America, and the whole world. Contemporaries were surprised by its high contagiousness as evidenced by attack rates averaging 60% in urban populations, its rapid spread in successive waves circling the globe in a few months by rail and sea, and the tendency of the disease to relapse. Despite its low case-fatality rate (0.10%-0.28%), it is estimated to have caused one million deaths worldwide. On serological grounds, it is generally accepted that the causative agent of Russian influenza was Myxovirus influenzae, the virus identified for all influenza pandemics since the “Spanish flu” of 1918. In light of the Covid-19 pandemic, which has underscored the extraordinary epidemic potential of coronaviruses, this assumption has recently been questioned. Coronaviruses come from wild reservoirs (bats, rodents, birds, …). They induce respiratory symptoms mimicking influenza, possibly leading to respiratory distress with pneumonia. In addition to the Covid-19 pandemic, recent deadly and limited epidemics, such as SARS in 2002 and MERS in 2012, have occurred. Russian influenza presented as an influenza-like syndrome with clinical peculiarities (multivisceral and neurological involvement, skin rash, early iterative relapses), evoking some particularities of Covid-19. Four other coronaviruses circulating in the human population for decades (HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1) have been found to be responsible for 15 to 30% of seasonal colds. All of these viruses are of animal origin. Recently, phylogenetic studies have revealed the genetic proximity between a bovine coronavirus BCoV and the human virus HCoV-OC43, indicating that the latter emerged around 1890, at the time of the Russian flu, when an epizootic was raging among cattle throughout Europe. Could the current human virus be the attenuated remnant that appeared after the Russian flu in 1894? Was there a coronavirus pandemic before Covid-19 ?

Yellow fever is a zoonotic arbovirosis, the agent of which is transmitted by mosquitoes. In humans, this virus can cause hemorrhagic hepato-nephritis, while mild or inapparent infections are common.

The catastrophic epidemics that occurred, mainly in the 18^th and the 19^th centuries, in Latin America and the United States as well as in the port cities of West Africa and Europe, had considerable demographic, socio-economic and political repercussions.

The viral nature of the infectious agent and its transmission by the Aedes aegypti mosquito, previously suspected by Beauperthuy, were demonstrated by Carlos Finlay in 1881 and confirmed by the American Commission led by Walter Reed in Havana in 1900 and by the French Commission led by Emile Marchoux in Rio de Janeiro in 1901-1905. The control of Ae. aegypti could then be implemented effectively.

It was only in 1927 that the yellow fever virus was isolated in Africa, its continent of origin, by French researchers from the Pasteur Institute in Dakar and by the American and English teams of the Rockefeller Foundation. Soon after, epidemiologists realized that there were forest cycles of the virus, involving monkeys and vectors other than Ae. aegypti, and consequently recognized the existence of a wild reservoir of the virus.

Once the virus was isolated, work on vaccine development could begin. This research was carried out by the Institut Pasteur in Dakar and by the Rockefeller Foundation. The two teams succeeded in obtaining two live vaccines conferring excellent and long-lasting protection: the neurotropic "Dakar" vaccine (1934) and the "Rockefeller" 17D vaccine (1937), which was better tolerated.

From then on, the fight against of yellow fever involved entomological control and vaccine protection, and it was a huge success until the 1960s. Unfortunately, the control programs were gradually reduced, and in some countries terminated. This resulted in the return of Ae. aegypti in urban areas and in insufficient vaccination coverage. Risks of epidemics reappeared, in Latin America as well as Africa.

In the early 21^st century, epidemiologists are worried about these resurgences, especially since we still have no indisputable explanation for the absence of the disease on the Asian continent. Obviously, yellow fever is not a disease of the past.

The Spanish flu occurred at the end of the First world war, in disastrous epidemiological conditions on populations exhausted by four years of war. At that time, there were no vaccines, no antibiotics, no oxygen and no resuscitation. It was even thought that the infectious agent was a bacterium. Humanity was poorly equipped to fight against a pandemic that caused 50–100 million deaths. The first palpable signs of the outbreak were the rapidly spreading multiple epidemics among young recruits in the American military training camps in March 1918. The flu then spread to the civilian populations and circled the globe twice, sparing no country, even the most remote islands, in tropical as well as polar climates, evolving in successive waves up until April 1919. The first was mild (lethality 0.21%), the second was lethal (lethality 2–4%), and during the third wave, lethality declined (1%), after which the flu became seasonal, with low lethality (0.1%). Between 20 and 40 years of age, patients often died within a few days of pneumonia, with respiratory distress leading to cyanosis, frequently associated with bacterial superinfection. The influenza virus, Myxovirus influenzae, was first discovered in 1931 by Richard Shope in pigs, and then in 1933 by Wilson Smith, Patrick Laidlaw and Christopher Andrews in humans during a seasonal influenza epidemic in London. In 1943, it was first observed under the electron microscope. Hemagglutinin and neuraminidase, the two main virulence factors, were discovered in the 1940s by George Hirst and Alfred Gottschalk. An RNA virus composed of 13,500 nucleotides in eight segments, it was initially sequenced in the 1980s, when Jeffrey Taubenberger determined the complete nucleotide sequence of the 1918 virus from lung tissue samples from patients who died of influenza. The 1918 H1N1 virus was found to have originated in birds. In 2005, it was successfully resuscitated in cell culture. It is 40,000 times more virulent in primates than the seasonal H1N1 virus. The lethality of the second wave could have been due to mutations in the hemagglutinin H1 gene, which would have resulted in a stronger affinity for α,2–6 galactose sialic acids, the virus' receptors on human epithelial cells. That said, the origin of the Spanish flu virus remains controversial. It probably emerged and circulated in the population before March 1918 in America, although European origin has also been evoked. The high mortality in the 20–40 age group remains an enigma. Some experts point to reduced immune response in patients previously exposed to related viral hemagglutinins during the 1889 pandemic. In any event, even though it concerns a markedly different virus, the history of the Spanish flu sheds light on the difficulties of management during today's pandemic.

Tuberculosis (TB), known as the White Plague’ is of great significance to humanity for the magnitude of morbidity and mortality it has generated over centuries from the very start of human civilization. In this Review, we will describe the history of prevention (vaccination and management of TB infection), diagnosis, treatment and pulmonary rehabilitation of post-treatment sequelae. The article leads the reader through the main discoveries which paved the way to the modern approach to TB prevention and care. The history of Bacille Calmette-Guérin (BCG) vaccine and of the diagnosis and treatment of TB infection are presented, together with that of diagnosis and treatment of TB disease. Pivotal was in 1882 the discovery by Robert Koch of the aetiological agent of TB, and his pioneering work in culturing the bacillus and developing tuberculin. Also of enormous importance was, in 1895, the discovery of the X-rays by Wilhelm Conrad Röntgen, discovery which paved the way to the development of the modern imaging technologies.

To complement this, the more recent history of rehabilitation of post-treatment sequelae is summarized, given the importance this issue has on patients’ wellbeing and Quality of Life.

Measles is a highly contagious viral disease transmitted by aerosols through human-to-human contact. It is often considered as a benign disease, although mortality remains high in developing countries (>5%). Frequent complications (diarrhea, otitis, pneumonia, encephalitis) can be observed. The disease mainly affects young children from 5 to 6 months of age with a mortality peak in the first three years of life. The Persian physician Rhazes gave the first clinical description of the disease in the 10th century, clearly differentiating it from smallpox. Measles spread worldwide from the Renaissance. Its epidemiology was remarkably studied in 1846 by a Danish physician, Peter Panum, during an epidemic in the Faroe Islands. The viral nature of this disease was demonstrated in 1911 and the virus was identified in 1954 by Thomas Peebles and John Enders. It is a morbillivirus (family Paramyxoviridae), also responsible for rinderpest (ovine, bovine), distemper (canine, feline), and epidemic diseases of dolphins, porpoises and seals. The current measles virus appeared recently from the rinderpest virus around the 6th century BCE. It has adapted perfectly to the human species, becoming strictly human, without animal reservoirs. A live attenuated vaccine was developed in 1958 by Enders' team after numerous passages in cell cultures. The vaccine was licensed in the United States in 1963 and is used on a large scale by the WHO throughout the world. This highly effective and well-tolerated vaccine has greatly reduced the number of measles cases and saved millions of lives. Measles remains a major public health concern, causing over 100,000 deaths per year worldwide. Today, the most affected continents remain Africa, South America and Asia.

For millions of years, invertebrates and malaria parasites have coexisted and to date, malaria remains the most important human parasitic disease. This co-evolution had profound impacts on the movements of early hominids and on the genome of modern humans. Over the past two centuries, progress has been made with the discovery of the parasite, its transmission, and medicines, paving the way to the control of the disease and its elimination in some countries. However, the Plasmodium parasite is a formidable foe capable of developing resistance to drugs, and the mosquito vector has adapted to insecticides, foiling all attempts to eradicate the disease. Over recent years the economic and social costs of malaria have been recognized and more funds have been mobilized than ever before, however further efforts are needed. National programs, international institutions and researchers will need to do better if the preventable deaths of hundreds of thousands of mostly African children are to be averted.

The plague epidemic of 1720-1722 had a profound effect on the history of the city of Marseille. A subject of numerous scientific studies and a source of inspiration for novels, one of the last great European epidemics is well-documented. In this article, we have sought to draw on the numerous documents left by the administrative services of the time or by the writings of survivors recounting their vision of the situation. We have completed this historical approach by referring to the study of mass graves of plague victims and will show how the simultaneous reading of two types of archives (historical and biological) can provide better anthropological knowledge of epidemic phenomena. The perspectives of interdisciplinary approaches to past infectious diseases are numerous, notably with the contributions of paleomicrobiology and genomics, and are particularly relevant today's health context.

In June 1981, the Centers for Disease Control (CDC) "Morbidity and Mortality Weekly Report" described the first cases of what was to be known as the Acquired Immunodeficiency Syndrome (AIDS). Two years later, the agent responsible for the disease, the human immunodeficiency virus (HIV), was identified. Since then, according to the World Health Organization an estimated 40 million people have died from the disease. Where does this virus come from, and why such an emergence in the late 20th century? These are the questions that it is now possible to answer in large part thanks to the numerous studies published over a little more than three decades. As with other emerging infectious diseases, initial cross-species transmission from an animal reservoir and subsequent favorable sociological factors associated with the evolution of human societies have led to the spread of a dramatic disease, for which no vaccine is presently available.