Antiviral drugs are a class of medication used for treating viral infections. Most antivirals target specific viruses, while a broad-spectrum antiviral is effective against a wide range of viruses. Unlike most antibiotics, antiviral drugs do not destroy their target pathogen; instead they inhibit its development.
Avian influenza, known informally as avian flu or bird flu, is a variety of influenza caused by viruses adapted to birds. The type with the greatest risk is highly pathogenic avian influenza (HPAI). Bird flu is similar to swine flu, dog flu, horse flu and human flu as an illness caused by strains of influenza viruses that have adapted to a specific host. Out of the three types of influenza viruses, influenza A virus is a zoonotic infection with a natural reservoir almost entirely in birds. Avian influenza, for most purposes, refers to the influenza A virus.
Oseltamivir, sold under the brand name Tamiflu, is an antiviral medication used to treat and prevent influenza A and influenza B, the viruses that cause the flu. Many medical organizations recommend it in people who have complications or are at high risk of complications within 48 hours of first symptoms of infection. They recommend it to prevent infection in those at high risk, but not the general population. The Centers for Disease Control and Prevention (CDC) recommends that clinicians use their discretion to treat those at lower risk who present within 48 hours of first symptoms of infection. It is taken by mouth, either as a pill or liquid.
Influenza vaccines, also known as flu jabs or flu shots, are vaccines that protect against infection by influenza viruses. New versions of the vaccines are developed twice a year, as the influenza virus rapidly changes. While their effectiveness varies from year to year, most provide modest to high protection against influenza. The United States Centers for Disease Control and Prevention (CDC) estimates that vaccination against influenza reduces sickness, medical visits, hospitalizations, and deaths. Immunized workers who do catch the flu return to work half a day sooner on average. Vaccine effectiveness in those over 65 years old remains uncertain due to a lack of high-quality research. Vaccinating children may protect those around them.
Live attenuated influenza vaccine (LAIV) is a type of influenza vaccine in the form of a nasal spray that is recommended for the prevention of influenza.
Swine influenza is an infection caused by any of several types of swine influenza viruses. Swine influenza virus (SIV) or swine-origin influenza virus (S-OIV) is any strain of the influenza family of viruses that is endemic in pigs. As of 2009, the known SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3.
The National Microbiology Laboratory (NML) is part of the Public Health Agency of Canada (PHAC), the agency of the Government of Canada that is responsible for public health, health emergency preparedness and response, and infectious and chronic disease control and prevention.
Flu season is an annually recurring time period characterized by the prevalence of an outbreak of influenza (flu). The season occurs during the cold half of the year in each hemisphere. Influenza activity can sometimes be predicted and even tracked geographically. While the beginning of major flu activity in each season varies by location, in any specific location these minor epidemics usually take about three weeks to reach its pinnacle, and another 3 weeks to significantly diminish.
The European Centre for Disease Prevention and Control (ECDC) is an agency of the European Union (EU) whose mission is to strengthen Europe's defences against infectious diseases. It covers a wide spectrum of activities, such as: surveillance, epidemic intelligence, response, scientific advice, microbiology, preparedness, public health training, international relations, health communication, and the scientific journal Eurosurveillance.
Respiratory tract infections (RTIs) are infectious diseases involving the respiratory tract. An infection of this type usually is further classified as an upper respiratory tract infection or a lower respiratory tract infection. Lower respiratory infections, such as pneumonia, tend to be far more severe than upper respiratory infections, such as the common cold.
An emergent virus is a virus that is either newly appeared, notably increasing in incidence/geographic range or has the potential to increase in the near future. Emergent viruses are a leading cause of emerging infectious diseases and raise public health challenges globally, given their potential to cause outbreaks of disease which can lead to epidemics and pandemics. As well as causing disease, emergent viruses can also have severe economic implications. Recent examples include the SARS-related coronaviruses, which have caused the 2002-2004 outbreak of SARS (SARS-CoV-1) and the 2019–21 pandemic of COVID-19 (SARS-CoV-2). Other examples include the human immunodeficiency virus which causes HIV/AIDS; the viruses responsible for Ebola; the H5N1 influenza virus responsible for avian flu; and H1N1/09, which caused the 2009 swine flu pandemic. Viral emergence in humans is often a consequence of zoonosis, which involves a cross-species jump of a viral disease into humans from other animals. As zoonotic viruses exist in animal reservoirs, they are much more difficult to eradicate and can therefore establish persistent infections in human populations.
Umifenovir, sold under the brand name Arbidol, is an antiviral medication for the treatment of influenza infection used in Russia and China. The drug is manufactured by Pharmstandard. Russian and China studies have shown it to be effective and it is approved in both countries while, it is not approved by the US FDA for the treatment or prevention of influenza because it was never applied for FDA approval since the drug company is in Russia not the US.
Vaccine efficacy or vaccine effectiveness is the percentage reduction of disease cases in a vaccinated group of people compared to an unvaccinated group. For example, a vaccine efficacy or effectiveness of 80% indicates an 80% decrease in the number of disease cases among a group of vaccinated people compared to a group in which nobody was vaccinated. When a study is carried out using the most favorable, ideal or perfectly controlled conditions, such as those in a clinical trial, the term vaccine efficacy is used. On the other hand, when a study is carried out to show how well a vaccine works when they are used in a bigger, typical population under less-than-perfectly controlled conditions, the term vaccine effectiveness is used.
Influenza-like illness (ILI), also known as flu-like syndrome or flu-like symptoms, is a medical diagnosis of possible influenza or other illness causing a set of common symptoms. These include fever, shivering, chills, malaise, dry cough, loss of appetite, body aches, and nausea, typically in connection with a sudden onset of illness. In most cases, the symptoms are caused by cytokines released by immune system activation, and are thus relatively non-specific.
The 2009 swine flu pandemic, caused by the H1N1 influenza virus and declared by the World Health Organization (WHO) from June 2009 to August 2010, is the third recent flu pandemic involving the H1N1 virus. The first two cases were discovered independently in the United States in April 2009. The virus appeared to be a new strain of H1N1 that resulted from a previous triple reassortment of bird, swine, and human flu viruses which further combined with a Eurasian pig flu virus, leading to the term "swine flu".
Coronavirus disease 2019 (COVID-19) is a contagious disease caused by a virus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The first known case was identified in Wuhan, China, in December 2019. The disease spread worldwide, leading to the COVID-19 pandemic.
Sir Jonathan Stafford Nguyen-Van-Tam is a British healthcare professional specialising in influenza, including its epidemiology, transmission, vaccinology, antiviral drugs and pandemic preparedness.
Arnold Monto is an American physician and epidemiologist. At the University of Michigan School of Public Health, Monto is the Thomas Francis Collegiate Professor of Public Health, professor of epidemiology, and professor of global public health. His epidemiologic focus is on occurrence, prevention, and treatment of acute infections in the individual and the community.
Allison Joan McGeer is a Canadian infectious disease specialist in the Sinai Health System, and a Professor in the Department of Laboratory Medicine and Pathobiology at the University of Toronto. She also appointed at the Dalla Lana School of Public Health and a Senior Clinician Scientist at the Lunenfeld-Tanenbaum Research Institute, and is a partner of the National Collaborating Centre for Infectious Diseases. McGeer has led investigations into the severe acute respiratory syndrome outbreak in Toronto and worked alongside Donald Low. During the COVID-19 pandemic, McGeer has studied how SARS-CoV-2 survives in the air and has served on several provincial committees advising aspects of the Government of Ontario's pandemic response.
A viral vector vaccine is a vaccine that uses a viral vector to deliver genetic material coding for a desired antigen into the recipient's host cells. As of April 2021, six viral vector vaccines have been authorized for use in humans in at least one country: four COVID-19 vaccines and two Ebola vaccines.
