A pandemic (/pænˈdɛmɪk/ pan-DEM-ik) is an epidemic of an infectious disease that has a sudden increase in cases and spreads across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals.Widespread endemic diseases with a stable number of infected individuals such as recurrences of seasonal influenza are generally excluded as they occur simultaneously in large regions of the globe rather than being spread worldwide.[10][11] Further, on 6 May 2024, the White House released an official policy to more safely manage medical research projects involving potentially hazardous pathogens, including viruses and bacteria, that may pose a risk of a pandemic.[19] A WHO-sponsored international body, tasked with preparing an international agreement on pandemic prevention, preparedness and response has defined a pandemic as "the global spread of a pathogen or variant that infects human populations with limited or no immunity through sustained and high transmissibility from person to person, overwhelming health systems with severe morbidity and high mortality, and causing social and economic disruptions, all of which require effective national and global collaboration and coordination for its control".A common early characteristic of a pandemic is a rapid, sometimes exponential, growth in the number of infections, coupled with a widening geographical spread.[21] WHO utilises different criteria to declare a Public Health Emergency of International Concern (PHEIC), its nearest equivalent to the term pandemic.[30] Routine vaccination programs are a type of prevention strategy, holding back diseases such as influenza and polio which have caused pandemics in the past, and could do so again if not controlled.[32] By definition, a pandemic involves many countries so international cooperation, data sharing, and collaboration are essential; as is universal access to tests and therapies.The Hub's initiatives include using artificial intelligence to analyse more than 35,000 data feeds for indications of emerging health threats, as well as improving facilities and coordination between academic institutions and WHO member countries.CEPI aims to reduce global epidemic and pandemic risk by developing vaccines against known pathogens as well as enabling rapid response to Disease X.It helps to predict the burden of disease on healthcare facilities, the effectiveness of control measures, projected geographical spread, and timing and extent of future pandemic waves.[40] Public awareness involves disseminating reliable information, ensuring consistency on message, transparency, and steps to discredit misinformation.[47] Another strategy, suppression, requires more extreme long-term non-pharmaceutical interventions to reverse the pandemic by reducing the basic reproduction number to less than 1.[72]It is assumed that, prior to the Neolithic Revolution around 10,000 BC, disease outbreaks were limited to a single family or clan, and did not spread widely before dying out.Beginning from the Middle Ages, encounters between European settlers and native populations in the rest of the world often introduced epidemics of extraordinary virulence.[106][107][108] In Australia, smallpox was introduced by European settlers in 1789 devastating the Australian Aboriginal population, killing an estimated 50% of those infected with the disease during the first decades of colonisation.[124] Following the end of the COVID-19 pandemic Public Health Emergency of International Concern deceleration by WHO, WHO Director General Tedros Ghebreyesus stated he would not hesitate to re-declare COVID-19 a PHEIC should the global situation worsen in the coming months or years.[132] More than two million respiratory specimens are tested by GISRS annually to monitor the spread and evolution of influenza viruses through a network of about 150 laboratories in 114 countries representing 91% of the world's population.[137] In the past 20 years, other common bacteria including Staphylococcus aureus, Serratia marcescens and Enterococcus, have developed resistance to a wide range of antibiotics.[140] The other group comprises water-borne diseases such as cholera, dysentery, and typhoid which may increase in prevalence due to changes in rainfall patterns.The "exponential rise" in consumption and trade of commodities such as meat, palm oil, and metals, largely facilitated by developed nations, and a growing human population, are the primary drivers of this destruction.The COVID-19 pandemic is expected to have a profound negative effect on the global economy, potentially for years to come, with substantial drops in GDP accompanied by increases in unemployment noted around the world.
Infographic illustrating the benefits of a treaty for pandemic prevention
Social distancing in public
Influenza intervals in the CDC's Pandemic Intervals Framework
Total confirmed cases of COVID-19 per million people
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A world map illustrating the proportion of population infected with HIV in 2019
1918 Chicago newspaper headlines reflect mitigation strategies for the
Spanish flu
, such as increased ventilation, arrests for "open-face sneezes and coughs", sequenced inoculations, limitations on crowd size, selective closing of businesses, curfews, and lockdowns.
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