Books on the topic 'Lassa fever'

Viral hemorrhagic fever (VHF) designates diseases caused by enveloped, single-stranded RNA viruses belonging to the families Ebola, Lassa, Hantavirus, and yellow fever. Unifying features include fever, capillary leak, and coagulation defects. These viruses can affect all organ systems; transmission occurs via contact with rodent excretions, either by ingestion or through mucosa or non-intact skin. Aerosolized rodent urine and saliva are also infectious. Person-to-person spread has been documented in Lassa and Machupo viruses, both by direct contact with bodily fluids and by airborne transmission. Thrombocytopenia is a common laboratory finding. Most acutely ill patients have high concentrations of virus in the blood as measured by polymerase chain reaction assay. Clinical differentiation between the various causes of VHF is difficult. Care is supportive. No antiviral drug, including ribavirin, has activity against these viruses. Most of these diseases do not occur naturally in the United States; however, some are considered viable for bioterrorism.

There are few groups of viral zoonoses that have attracted such widespread publicity as the arenaviruses, particularly during the 1960’s and 1970’s when Lassa emerged as a major cause of haemorrhagic disease in West Africa. More than any other zoonoses, members of the family are used extensively for the study of virus-host relationships. Thus the study of this unique group of enveloped, single-stranded RNA viruses has been pursued for two quite separate reasons. First, lymphocytic choriomeningitis virus (LCM) has been used as a model of persistent virus infections for over half a century; its study has contributed, and continues to contribute, a number of cardinal concepts to our present understanding of immunology. LCM virus remains the prototype of the Arenaviridae and is a common infection of laboratory mice, rats and hamsters. Once thought rare in humans there is now increasing evidence of LCM virus being implicated in renal disease and as a complication in organ transplantation. Second, certain arenaviruses cause severe haemorrhagic diseases in man, notably Lassa fever in Africa, Argentine and Bolivian haemorrhagic fevers in South America, Guaranito infection in Venezuela and Chaparé virus in Bolivia. The latter is a prime example for the need of ever-continuing vigilance for the emergence of new viral diseases; over the past few years several new arenaviruses have been reported as implicated with severe human disease and indeed the number of new arenaviruses discovered since the last edition of this book have increased the size of this virus family significantly.In common with LCM, the natural reservoir of these infections is a limited number of rodent species (Howard, 1986). Although the initial isolates from South America were at first erroneously designated as newly defined arboviruses, there is no evidence to implicate arthropod transmission for any arenavirus. However, similar methods of isolation and the necessity of trapping small animals have meant that the majority of arenaviruses have been isolated by workers in the arbovirus field. A good example of this is Guaranito virus that emerged during investigation of a dengue virus outbreak in Venezuela (Salas et al. 1991).There is an interesting spectrum of pathological processes among these viruses. All the evidence so far available suggests that the morbidity of Lassa fever and South American haemorrhagic fevers due to arenavirus infection results from the direct cytopathic action of these agents. This is in sharp contrast to the immunopathological basis of ‘classic’ lymphocytic choriomeningitis disease seen in adult mice infected with LCM virus and the use of this system for elucidating the phenomenon of H2-restriction of the host cytotoxic T cell response (Zinkernagel and Doherty 1979). Despite the utility of this experimental model for dissecting the nature of the immune response to virus infection and the growing interest in arenaviruses of rodents, there remains much to be done to elucidate the pathogenesis of these infections in humans.

“Viruses, Plagues, & History” focuses on the effects of viral diseases on human history. Written by an eminent internationally respected virologist, it couples the fabric of history with major concepts developed in virology, immunology, vaccination, and accounts by people who first had, saw and acted at the times these events occurred. Much of the preventive and therapeutic progress (vaccines, antiviral drugs) has been made in the last 60 years. Many of those who played commanding roles in the fight to understand, control and eradicate viruses and viral diseases are (were) personally known to the author and several episodes described in this book reflect their input. The book records the amazing accomplishments that led to the control of lethal and disabling viral diseases caused by Smallpox, Yellow Fever, Measles, Polio, Hepatitis A, B and C, and HIV. These six success stories are contrasted with viral infections currently out of control—COVID-19, Ebola virus, Lassa Fever virus, Hantavirus, West Nile virus, and Zika. Influenza, under reasonable containment at present, but with the potential to revert to a world-wide pandemic similar to 1918–1919 where over 50 million people were killed. The new platforms to develop inhibitory and prophylactic vaccines to limit these and other viral diseases is contrasted to the anti-vaccine movement and the false prophets of autism.

The last four decades of human history have seen the emergence of an unprecedented number of 'new' infectious diseases: the familiar roll call includes AIDS, Ebola, H5N1 influenza, hantavirus, hepatitis E, Lassa fever, legionnaires' and Lyme diseases, Marburg fever, Rift Valley fever, SARS, and West Nile. The outbreaks range in scale from global pandemics that have brought death and misery to millions, through to self-limiting outbreaks of mainly local impact. Some outbreaks have erupted explosively but have already faded away; some grumble along or continue to devastate as now persistent features in the medical lexicon; in others, a huge potential threat hangs uncertainly and worryingly in the air. Some outbreaks are merely local, others are worldwide. This book looks at the epidemiological and geographical conditions which underpin disease emergence. What are the processes which lead to emergence? Why now in human history? Where do such diseases emerge and how do they spread or fail to spread around the globe? What is the armoury of surveillance and control measures that may curb the impact of such diseases? But, uniquely, it sets these questions on the modern period of disease emergence in an historical context. First, it uses the historical record to set recent events against a much broader temporal canvas, finding emergence to be a constant theme in disease history rather than one confined to recent decades. It concludes that it is the quantitative pace of emergence, rather than its intrinsic nature, that separates the present period from earlier centuries. Second, it looks at the spatial and ecological setting of emergence, using hundreds of specially-drawn maps to chart the source areas of new diseases and the pathways of their spread. The book is divided into three main sections: Part 1 looks at early disease emergence, Part 2 at the processes of disease emergence, and Part 3 at the future for emergent diseases.