Hellenic holocaust: a historical clinico-pathologic conference

Absenteeism of Healthcare Personnel in the COVID-19 Era: A Systematic Review of the Literature and Implications for the Post-Pandemic Seasons

This systematic review aimed to assess COVID-19-associated absenteeism among healthcare personnel (HCP). PubMed was searched on 4 February 2023. Inclusion criteria were the presentation of original data on COVID-19-associated absenteeism among HCP. Exclusion criteria were absenteeism associated with burnout, mental health illness, post-COVID syndrome, or child-care. Nineteen articles were identified; fifteen concerned almost exclusively the first pandemic year. Hospitals accounted for most data. There was heterogeneity across studies in terms of presentation of absenteeism data. Before COVID-19 vaccines became available, COVID-19 was a major driver of HCP absenteeism with excess costs, while the mean duration of absenteeism ranged from 5.82 to 33 days per episode of absence. Determinant factors of absenteeism rates were department of employment, high-risk exposure, age, profession, and work experience of HCP, suspected COVID-19, SARS-CoV-2 testing, SARS-CoV-2 positivity, and return-to-work strategy. Two studies demonstrated that COVID-19 vaccination significantly reduced the burden of absenteeism. Routine testing of asymptomatic HCP and use of personal protective equipment also significantly ameliorated absenteeism. In conclusion, COVID-19 has been a major driver of HCP absenteeism. Research is needed to assess how COVID-19 will impact HCP in the next years, considering the new SARS-CoV-2 variants, the co-circulation of other respiratory viruses, and the newer COVID-19 vaccines. Networks are needed to survey morbidity and absenteeism among HCP in real-time and guide vaccination policies.

Travel vaccines throughout history

Vaccinations are an important component of travel medicine. Beyond protection of travelers, vaccines are administered to prevent the importation of vaccine-preventable diseases at home and at destination. Proof of immunization to travel dates back to the first smallpox vaccine, developed by Edward Jenner in 1796. However, it took one century to generate the next vaccines against cholera, rabies, and typhoid fever. During the 20th century the armamentarium of vaccines used in travelers largely expanded with yellow fever, poliomyelitis, tetravalent meningococcal, and hepatitis A vaccines. The International Certificate of Inoculation and Vaccination was implemented in 1933. Currently there are vaccines administered to travelers following risk assessment, but also vaccines required according to the 2005 International Health Regulations and vaccines required at certain countries. Finally, within less than one year after the declaration of the coronavirus disease 2019 (COVID-19) pandemic, the first COVID-19 vaccines were launched and approved for emergency use to control the pandemic. Despite practical and ethical challenges, COVID-19 vaccine verifications have been widely used since spring 2021 in many activities, including international travel. In this article, we review the course of development of travel vaccines focusing on those for which a proof of vaccination has been or is required.

Palaeopathology and genes: investigating the genetics of infectious diseases in excavated human skeletal remains and mummies from past populations

The aim of this paper is to review the use of genetics in palaeomicrobiology, and to highlight the importance of understanding past diseases. Palaeomicrobiology is the study of disease pathogens in skeletal and mummified remains from archaeological contexts. It has revolutionarised our understanding of health in the past by enabling a deeper knowledge of the origins and evolution of many diseases that have shaped us as a species. Bacterial diseases explored include tuberculosis, leprosy, bubonic plague, typhoid, syphilis, endemic and epidemic typhus, trench fever, and Helicobacter pylori. Viral diseases discussed include influenza, hepatitis B, human papilloma virus (HPV), human T-cell lymphotrophic virus (HTLV-1) and human immunodeficiency virus (HIV). Parasitic diseases investigated include malaria, leishmaniasis, Chagas' disease, roundworm, whipworm, pinworm, Chinese liver fluke, fleas and lice. Through a better understanding of disease origins and their evolution, we can place into context how many infectious diseases are changing over time, and so help us estimate how they may change in the future.

The plague of Thebes, a historical epidemic in Sophocles' Oedipus Rex

Sophocles, one of the most noted playwrights of the ancient world, wrote the tragedy Oedipus Rex in the first half of the decade 430-420 bc. A lethal plague is described in this drama. We adopted a critical approach to Oedipus Rex in analyzing the literary description of the disease, unraveling its clinical features, and defining a possible underlying cause. Our goals were to clarify whether the plague described in Oedipus Rex reflects an actual historical event; to compare it with the plague of Athens, which was described by Thucydides as occurring around the same time Sophocles wrote; and to propose a likely causative pathogen. A critical reading of Oedipus Rex and a comparison with Thucydides' history, as well as a systematic review of historical data, strongly suggests that this epidemic was an actual event, possibly caused by Brucella abortus.

DNA examination of ancient dental pulp incriminates typhoid fever as a probable cause of the Plague of Athens

BACKGROUND

Until now, in the absence of direct microbiological evidence, the cause of the Plague of Athens has remained a matter of debate among scientists who have relied exclusively on Thucydides' narrations to introduce several possible diagnoses. A mass burial pit, unearthed in the Kerameikos ancient cemetery of Athens and dated back to the time of the plague outbreak (around 430 BC), has provided the required skeletal material for the investigation of ancient microbial DNA.

OBJECTIVE

To determine the probable cause of the Plague of Athens.

METHOD

Dental pulp was our material of choice, since it has been proved to be an ideal DNA source of ancient septicemic microorganisms through its good vascularization, durability and natural sterility.

RESULTS

Six DNA amplifications targeted at genomic parts of the agents of plague (Yersinia pestis), typhus (Rickettsia prowazekii), anthrax (Bacillus anthracis), tuberculosis (Mycobacterium tuberculosis), cowpox (cowpox virus) and cat-scratch disease (Bartonella henselae) failed to yield any product in 'suicide' reactions of DNA samples isolated from three ancient teeth. On the seventh such attempt, DNA sequences of Salmonella enterica serovar Typhi were identified providing clear evidence for the presence of that microorganism in the dental pulp of teeth recovered from the Kerameikos mass grave.

CONCLUSION

The results of this study clearly implicate typhoid fever as a probable cause of the Plague of Athens.

The cause of the plague of Athens: plague, typhoid, typhus, smallpox, or measles?

The plague of Athens raged for 4 years and resulted in the defeat of Athens. The cause of the plague of Athens continues to be debated. Infectious diseases most often cited as causes of the plague include influenza, epidemic typhus, typhoid fever, bubonic plague, smallpox, and measles. Thucydides provides the only available description of the plague of Athens. Given the nuances of the translation, bubonic plague, smallpox, and measles are the most likely causes of the plague. In my view, measles is the most likely cause of the plague of Athens.

The history of epidemic typhus

Few infectious diseases have influenced human civilization to the same degree as louse-transmitted typhus. Rickettsia prowazekii continues to strikes tens to hundreds of thousands of persons who live with war, famine, crowding, and in squalid conditions associated with social unrest, with mortality rates in excess of 10% to 15%. Historical documents confirm that such devastation has been a continuous feature of human existence to the extent that typhus has been a major determinant in the outcome of many wars, altering human history in its wake-despite incomplete knowledge of its precise origin. In the twenty-first century, circumstances are still conductive for outbreak; the emerging threat of bioterrorism raises justifiable concerns that typhus could affect civilization just as greatly in the future as it has in the past.

The plague under Marcus Aurelius and the decline and fall of the Roman Empire

The Roman Empire of the second century was a superpower that, in relative terms, dominated its world as much as the United States does today. In 166 AD, a plague broke out od pandemic proportions. The pandemic ravaged the entire extent of the Roman Empire, from its eastern frontiers in Iraq to its western frontiers on the Rhine River and Gaul, modern France, and western Germany. The disease is identified most often as smallpox, but it may have been anthrax. The study of bacterial DNA may enable identification of this plague that ravaged the Roman Empire at recurrent intervals for more than 100 years and that had a significant role in the decline and fall of this great superpower.