In virology, influenza A virus subtype H1N1 (A/H1N1) is a subtype of influenza A virus. Major outbreaks of H1N1 strains in humans include the Spanish flu, the 1977 Russian flu pandemic and the 2009 swine flu pandemic. It is an orthomyxovirus that contains the glycoproteins hemagglutinin and neuraminidase. For this reason, they are described as H1N1, H1N2 etc., depending on the type of H or N antigens they express with metabolic synergy. Hemagglutinin causes red blood cells to clump together and binds the virus to the infected cell. Neuraminidase is a type of glycoside hydrolase enzyme which helps to move the virus particles through the infected cell and assist in budding from the host cells.
An influenza pandemic is an epidemic of an influenza virus that spreads across a large region and infects a large proportion of the population. There have been six major influenza epidemics in the last 140 years, with the 1918 flu pandemic being the most severe; this is estimated to have been responsible for the deaths of 50–100 million people. The most recent, the 2009 swine flu pandemic, resulted in under 300,000 deaths and is considered relatively mild. These pandemics occur irregularly.
The 2009 flu pandemic in the United States was caused by a novel strain of the Influenza A/H1N1 virus, commonly referred to as "swine flu", that was first detected on 15 April 2009. While the 2009 H1N1 virus strain was commonly referred to as "swine flu", there is no evidence that it is endemic to pigs or of transmission from pigs to people; instead, the virus spreads from person to person. On April 25, the World Health Organization declared a public health emergency, followed concurringly by the Obama administration on April 26.
This article covers the chronology of the 2009 novel influenza A (H1N1) pandemic. Flag icons denote the first announcements of confirmed cases by the respective nation-states, their first deaths, and relevant sessions and announcements of the World Health Organization (WHO), the European Union , and the U.S. Centers for Disease Control (CDC).
The 2009 flu pandemic was a global outbreak of a new strain of influenza A virus subtype H1N1, first identified in April 2009, termed Pandemic H1N1/09 virus by the World Health Organization (WHO) and colloquially called swine flu. The outbreak was first observed in Mexico, and quickly spread globally. On 11 June 2009, the WHO declared the outbreak to be a pandemic. The overwhelming majority of patients experienced mild symptoms, but some persons were in higher risk groups, such as those with asthma, diabetes, obesity, heart disease, who were pregnant or had a weakened immune system. In the rare severe cases, around 3–5 days after symptoms manifest, the sufferer's condition declines quickly, often to the point of respiratory failure.
This article deals with the status and efforts regarding the 2009 swine flu pandemic by country and continent/region.
The 2009 flu pandemic in Asia, part of an epidemic in 2009 of a new strain of influenza A virus subtype H1N1 causing what has been commonly called swine flu, afflicted at least 394,133 people in Asia with 2,137 confirmed deaths: there were 1,035 deaths confirmed in India, 737 deaths in China, 415 deaths in Turkey, 192 deaths in Thailand, and 170 deaths in South Korea. Among the Asian countries, South Korea had the most confirmed cases, followed by China, Hong Kong, and Thailand.
The 2009 flu pandemic hit Africa two months later than other continents with the first case reported in Egypt on June 2, 2009. As of December 1, 30 countries in Africa had reported cases and 7 countries in Africa had reported a total of 108 deaths. It was the least affected continent.
This is a table containing the figures from the WHO Influenza A Situation Updates issued in April 2009 roughly once a day. Where more than one update was issued in a day, the figures are from the last update that day. The table can by sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the WHO Influenza A Situation Updates issued in May 2009 roughly once a day. Where more than one update was issued in a day, the corresponding figures are from the last update that day. The table can by sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the WHO Influenza A Situation Updates issued in June 2009 roughly three times a week. The table can by sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the WHO Influenza A Situation Updates issued in July 2009 roughly three times a week, and, since 15 July, figures from ECDC. The table can by sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the ECDC Influenza A Situation Updates issued in August 2009 roughly three times a week. From 10 August, ECDC only published deaths totals outside its area. The table can by sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the ECDC Influenza A Situation Updates issued in September 2009 roughly three times a week. From 10 August, ECDC only published deaths totals outside its area, and so the world cases table has not been maintained. The table can be sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the ECDC Influenza A Situation Updates issued in October 2009 roughly three times a week. From 30 September, ECDC only published deaths totals, and so the world cases table has not been maintained. The table can be sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the ECDC Influenza A Situation Updates issued in November 2009 roughly three times a week. From 30 September, ECDC only published deaths totals, and so the world cases table has not been maintained. The table can be sorted by country, date of first confirmed case or date of first confirmed case by continent.
This is a table containing the figures from the ECDC Influenza A Situation Updates issued in December 2009 roughly three times a week. From 30 September, ECDC only published deaths totals, and so the world cases table has not been maintained. The table can be sorted by country, date of first confirmed case or date of first confirmed case by continent.
The 2018 Middle East respiratory syndrome outbreak was a set of infections of Middle East respiratory syndrome (MERS-CoV). The cases were most numerous in, and are believed to have originated from, Saudi Arabia.
This is a general overview and status of places affected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus which causes coronavirus disease 2019 (COVID-19) and is responsible for the COVID-19 pandemic. The first human cases of COVID-19 were identified in Wuhan, the capital of the province of Hubei in China in December 2019.
The article contains the number of cases of coronavirus disease 2019 (COVID-19) reported by each country, territory, and subnational area to the World Health Organization (WHO) and published in WHO reports, tables, and spreadsheets. As of 21 October 2022, 626,794,437 cases have been stated by government agencies from around the world to be confirmed. For more international statistics in table and map form, see COVID-19 pandemic by country and territory.
Mexico 
United States of America 
Canada 
Costa Rica 
El Salvador 
Guatemala 
Panama 
Cuba 
Honduras 
Dominican Republic 
Bahamas 
Jamaica 
Nicaragua 
Barbados 
Cayman Islands 
Dominica 
Trinidad and Tobago 
Bermuda 
British Virgin Islands 
Martinique 
Netherlands Antilles 
Antigua and Barbuda 
Saint Lucia 
Aruba 
Puerto Rico 
US Virgin Islands 
Saint Vincent and the Grenadines 
Belize 
Haiti 
Saint Kitts and Nevis 
Grenada 
Turks and Caicos Islands 
Anguilla 
Spain 
United Kingdom 
Austria 
Germany 
Netherlands 
Switzerland 
Denmark 
Ireland 
Italy 
Portugal 
Sweden 
Poland 
Norway 
Finland 
Belgium 
Greece 
Russia 
Iceland 
Romania 
Czech Republic 
Slovakia 
Cyprus 
Estonia 
Hungary 
Bulgaria 
Luxembourg 
Ukraine 
Isle of Man 
Jersey 
Slovenia 
Latvia 
Montenegro 
Serbia 
Guernsey 
Lithuania 
Monaco 
Malta 
Bosnia and Herzegovina 
Macedonia 
Croatia 
Georgia 
Albania 
Andorra 
Kosovo 
Azerbaijan 
Moldova 
Liechtenstein 
Israel 
China 
Korea, Republic of 
Japan 
Thailand 
India 
Malaysia 
Turkey 
Philippines 
Taiwan 
Kuwait 
Bahrain 
Singapore 
Viet Nam 
Lebanon 
Saudi Arabia 
United Arab Emirates 
West Bank and Gaza Strip 
Qatar 
Jordan 
Sri Lanka 
Yemen 
Oman 
Laos 
Papua New Guinea 
Bangladesh 
Brunei 
Cambodia 
Indonesia 
Iran 
Iraq 
Nepal 
Myanmar 
Syria 
Afghanistan 
Bhutan 
Maldives 
Kazakhstan 
Pakistan 
New Zealand 
Australia 
French Polynesia 
Samoa 
Fiji 
Vanuatu 
New Caledonia 
Palau 
Cook Islands 
Guam 
Tonga 
Solomon Islands 
Federated States of Micronesia 
Marshall Islands 
Nauru 
Kiribati 
Colombia 
Brazil 
Argentina 
Ecuador 
Peru 
Chile 
Uruguay 
Paraguay 
Bolivia 
Venezuela 
Suriname 
Guyana 
Falkland Islands 
Egypt 
Morocco 
South Africa 
Algeria 
Cape Verde 
Cote d'Ivoire 
Tunisia 
Ethiopia 
Mauritius 
Kenya 
Uganda 
Libya 
Seychelles 
Tanzania 
Botswana 
Sudan 
Namibia 
Swaziland 
Gabon 
Ghana 
