Malaria is the most important parasitic disease in the world. Human malaria is a blood-borne protozoal infection caused by five species of the genus Plasmodium : P. falciparum , P. vivax , P. ovale , P. malariae , and P. knowlesi . The infection is transmitted through the bite of infected female Anopheles mosquitoes. Less commonly, malaria may be transmitted by blood transfusion, with shared needle…
Recommendations for travel immunizations are based on a risk assessment of each traveler's general health, trip itinerary, and knowledge of current health conditions at a given destination. Most travelers seek protection against vaccine-preventable diseases, yet their acceptance of the vaccines recommended for travel may depend largely on other concerns, such as number of doses and vaccine schedules, route of administration (oral vs. injection), and cost. Many…
Once onboard a commercial jet aircraft headed to destination, the traveler faces the novel environment of the airplane cabin, in which a passenger's health may be impacted by the air quality and pressurization, among other prevailing conditions. Chronic health concerns may be exacerbated and new health issues may arise after spending hours sitting with limited mobility in the company of strangers and in contact with potentially…
In 1992 a landmark report by the Institute of Medicine titled “Emerging Infections: Microbial Threats to Health in the United States” highlighted the importance of the often underappreciated concept of emerging infectious diseases (EIDs). This report brought EIDs back into scientific discourse; however, the awareness that diseases emerge and periodically reemerge goes back millenia, as highlight in their historical review. The term “emerging infectious diseases” is…
Each year, more than 50 million travelers from industrialized nations visit low-income nations. Whereas many travelers and travel providers associate international travel with rustic and sparsely peopled environments, an increasing proportion of travelers, including students and international business travelers, spend most or all of their time abroad in urban environments. Even tourists whose final destinations are rural and remote must contend with urban settings for at…
Coronavirus Infections in Children and Adolescents Coronaviruses are enveloped single-stranded RNA viruses comprising four genera: alpha, beta, gamma, and delta. They infect humans and animals and were first described in the 1960s as causative agents of mild upper respiratory tract infections. Four human coronaviruses caused up to 35% of upper respiratory tract infections in humans: 2229E, NL63 (both alpha coronaviruses), and HKU1 and OC43 (beta coronaviruses).…
A new medical specialty, travel medicine, emerged in the 1980s in response to the health needs of increasing numbers of international travelers—a phenomenon resulting from the rapid expansion and growing accessibility of commercial jet transportation. In 1990, the World Tourism Organization (WTO) reported approximately 457 million international arrivals per year. In 2014, the WTO reported 1138 million international arrivals per year, and just under half of…
History of Perinatal Coronavirus Infections Before the worldwide pandemic, data on coronavirus infection in pregnancy were limited despite two previous large epidemics. A 2020 systematic review and meta-analysis found only 12 cases of Middle East respiratory syndrome coronavirus (MERS-CoV) and 33 cases of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections in pregnancy, all of which were from case reports, case series, or small retrospective cohort studies.…
Introduction Neuropsychiatric sequelae of viral infections have been described in the literature and are well known from studies of influenza pandemics , , human immunodeficiency virus (HIV) infections, and viral encephalitis. Perhaps the most researched neuropsychiatric disorder after a viral infection was the development of encephalitis lethargica after the Spanish flu outbreak in the last century. Encephalitis lethargica had prominent parkinsonian symptoms, psychosis, and catatonia. Prominent…
Introduction and Historical Perspectives In late December 2019, an ophthalmologist named Li Wenliang sent a message to a group of fellow physicians in Wuhan, China, warning them of an emerging respiratory illness that he thought bore resemblance to severe acute respiratory syndrome (SARS). Weeks later, after local authorities admonished him for “spreading rumors,” Dr. Li contracted the virus from one of his glaucoma patients and passed…
Acute Kidney Injury Incidence and Mortality Associated With SARS-CoV-2 Infection AKI incidence has varied based on the geographic location and clinical situation during the pandemic. A meta-analysis of over 13,000 patients reported an AKI prevalence of 17%, although the range from the individual studies that made up the meta-analysis was broad at 0.5% to 80%. Critically ill patients are more likely to have AKI in the…
OUTLINE Prevalence of Gastrointestinal Symptoms, 191 Implications of Gastrointestinal Symptoms in COVID-19, 191 Mechanism on How SARS-CoV-2 Affects Gut Health, 192 Angiotensin-Converting Enzyme-2 Receptor Mechanism, 192 Impact of SARS-CoV-2 on Gut Microbiota, 193 Impact of Gastric Acid Reduction on COVID-19 Outcomes, 193 Proton Pump Inhibitors, 193 Histamine Receptor Antagonists (H 2 -Blockers), 194 Impact of COVID-19 in Inflammatory Bowel Disease, 194 Pathogenesis of COVID-19 in Inflammatory Bowel…
The Oral Cavity and Viral Infections The oral cavity is home to a vast microbial flora that also include a robust community of viruses. Although the viruses that infect bacteria or bacteriophages constitute the majority, viruses that infect human cells form a significant component of the oral microbiome. , Much like bacteria, viral communities are also site-specific alterations that can lead to disease. Indeed, one of…
OUTLINE Epidemiology of Neurological Manifestations of COVID-19, 159 Historical Background of Neurological Effects of the Coronavirus Family, 160 Pathophysiology, Pathogenesis, and Proposed Mechanisms of the SARS-CoV-2 Virus and the Nervous System, 161 COVID-19 and the Peripheral Nervous System, 162 Anosmia and Dysgeusia, 162 Guillain-Barré Syndrome and Associated Variants, 163 COVID-19 and the Central Nervous System, 166 Encephalopathy and Encephalitis, 166 Transverse Myelitis, 166 Seizures, 166 Cerebrovascular…
OUTLINE Epidemiology of Cardiac Injury From COVID-19, 137 History of Cardiovascular Effects From SARS-CoV-1 and MERS-CoV, 138 Pathophysiology and Potential Mechanisms of Cardiovascular Injury From COVID-19, 138 Renin-Angiotensin System, 138 Direct Infection of the Myocardium, 139 Cytokine-Mediated Cardiac Injury, 140 COVID-19–Associated Thrombosis, 140 Clinical Manifestations and Complications, 143 Myocarditis, 143 Acute Coronary Syndrome, 143 Heart Failure, 144 Cardiac Arrhythmias, 144 Thromboembolic Events, 145 Cardiovascular Comorbidities and…
OUTLINE COVID-19 Manifestations in the Respiratory System, 100 Clinical Presentation, 100 Complications, 101 Acute Respiratory Distress Syndrome, 102 COVID-19 Acute Respiratory Distress Syndrome, 111 Lung Microbiome and COVID-19, 114 Specific COVID-19 Pulmonary Complications, 115 COVID-19 Long-Term Pulmonary Complications, 116 Treatment and Management of Salient Pulmonary Manifestations and Complications of COVID-19, 118 Treatment of Hypoxemia, 118 Management of Respiratory Failure, 119 Management of COVID-19 Pneumonia and Pneumonitis,…
OUTLINE Short Comparison of SARS-CoV-2 With SARS-CoV-1 and MERS-CoV, 72 Natural History, 73 Incubation Period, 73 Spectrum of COVID-19, 74 Pathogenicity and Virulence, 74 Asymptomatic Disease and Carrier Status, 75 Asymptomatic Patient Trajectories, 75 Symptomatic Patient Trajectories, 76 Demographics, 76 Pathogenesis, 76 Clinical Characteristics, 76 Respiratory and Pulmonary Manifestations, 76 Cardiovascular Manifestations, 77 Neurological Manifestations, 77 Gastrointestinal Manifestations, 78 Renal Manifestations, 78 Cutaneous Manifestations, 82 Ocular…
The extraordinary global spread of SARS-CoV-2 through naïve populations provides compelling evidence of both the strengths and limitations of the human immune response: on the one hand, recognizing and eliminating a novel viral pathogen, while on the other, causing potentially lethal immunopathological conditions ( Fig. 3.1 ). The pandemic also provided a striking opportunity to understand SARS-CoV-2 pathogenesis through a lens offered by multiple clinical trials. COVID-19…
SARS-CoV-2 and Coronaviruses Evolutionary Origins In the last two decades, three coronaviruses have caused outbreaks of varying scales, with the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) representing the most recent threat to human health at a global level. Aside from severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV), which were responsible for the first two outbreaks of…
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes a highly contagious disease called CO rona VI rus D isease 2019 (COVID-19). The virus was first reported in Wuhan city, Hubei Province of China in December 2019; in less than 3 months it spread globally and was declared a global pandemic by the World Health Organization (WHO) on March 11, 2020. By March 24, 2020, the novel…