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 other major events such as their first intergenerational cases, cases of zoonosis, and the start of national vaccination campaigns), and relevant sessions and announcements of the World Health Organization (WHO), the European Union (and its agency the European Centre for Disease Prevention and Control), and the U.S. Centers for Disease Control (CDC).
Unless otherwise noted, references to terms like S-OIV, H1N1 and such, all refer to this new A(H1N1) strain and not to sundry other strains of H1N1 which are endemic in humans, birds and pigs.
2009 | A(H1N1) Outbreak and Pandemic Milestones |
---|---|
17 March | First case in the world of what was later identified as swine flu origin. |
28 March | First country's case affected the disease in the US of what was later identified as swine flu origin. |
12 April | First known death due to what was later identified as swine flu origin. |
24 April | First Diseases Outbreak Notice mention of the Swine Flu by the World Health Organization. |
25 April | The United States is the first country to have Community outbreaks confirmed. |
Community outbreaks confirmed in Mexico. | |
27 April | First case confirmed in Canada. |
First case confirmed in Spain. | |
First case confirmed in the United Kingdom. | |
28 April | First case confirmed in Israel. |
First case confirmed in New Zealand. | |
29 April | First death confirmed in the United States. |
First case confirmed in Germany. | |
First case confirmed in Austria. | |
30 April | First case confirmed in the Netherlands. |
First case confirmed in Switzerland. | |
First case confirmed in Ireland. | |
1 May | First case confirmed in Hong Kong, China. |
First case confirmed in Denmark. | |
First case confirmed in France. | |
2 May | First case confirmed in Italy. |
First case confirmed in South Korea. | |
First case confirmed in Costa Rica. | |
3 May | First case confirmed in Colombia. |
First case confirmed in Portugal. | |
First human-to-animal transmission of the virus in Canada | |
4 May | First case confirmed in El Salvador. |
5 May | First case confirmed in Guatemala. |
6 May | First case confirmed in Poland. |
First case confirmed in Sweden. | |
7 May | First case confirmed in Argentina. |
First case confirmed in Brazil. | |
First death confirmed in Canada. | |
First case of zoonosis in Canada, where an infected pig infects a human | |
8 May | First case confirmed in Japan. |
First case confirmed in Panama. | |
Community outbreaks confirmed in Canada. | |
9 May | First case confirmed in Australia. |
First case confirmed in Norway. | |
First death confirmed in Costa Rica. | |
10 May | First case confirmed in China. |
12 May | First case confirmed in Thailand. |
First case confirmed in Cuba. | |
First case confirmed in Finland. | |
13 May | First case confirmed in Belgium. |
Community outbreaks confirmed in Costa Rica. | |
14 May | First case confirmed in Peru. |
15 May | First case confirmed in Malaysia. |
First case confirmed in Ecuador. | |
16 May | First case confirmed in India. |
First case confirmed in Turkey. | |
17 May | First case confirmed in Chile. |
Community outbreaks confirmed in Japan. | |
18 May | First case confirmed in Greece. |
19 May | First case confirmed in Paraguay. |
First case confirmed in Taiwan. | |
21 May | First case confirmed in the Philippines. |
22 May | First case confirmed in Honduras. |
First case confirmed in Russia. | |
23 May | First case confirmed in Iceland. |
24 May | First case confirmed in Kuwait. |
First case confirmed in United Arab Emirates. | |
25 May | First case confirmed in Bahrain. |
First case confirmed in Czech Republic. | |
26 May | First case confirmed in Puerto Rico. |
Community outbreaks confirmed in United Kingdom. | |
27 May | First case confirmed in Romania. |
First case confirmed in Singapore. | |
First case confirmed in Dominican Republic. | |
First case confirmed in Uruguay. | |
28 May | First case confirmed in Bolivia. |
First case confirmed in Venezuela. | |
First case confirmed in Slovakia. | |
Community outbreaks confirmed in Argentina. | |
Community outbreaks confirmed in Australia. | |
29 May | First case confirmed in Hungary. |
30 May | First case confirmed in Cyprus. |
First case confirmed in Estonia. | |
First case confirmed in Lebanon. | |
Community outbreaks confirmed in Chile. | |
31 May | First case confirmed in Vietnam. |
First case confirmed in Bahamas. | |
Community outbreaks confirmed in Germany. | |
1 June | First case confirmed in Bulgaria. |
2 June | First death confirmed in Chile. |
First case confirmed in Luxembourg. | |
First case confirmed in Ukraine. | |
First case confirmed in Nicaragua. | |
First case confirmed in Egypt. | |
First case confirmed in Bermuda. | |
3 June | First case confirmed in Saudi Arabia. |
First case confirmed in Barbados. | |
First case confirmed in Jamaica. | |
4 June | First case confirmed in Trinidad and Tobago. |
5 June | First death confirmed in Dominican Republic. |
First case confirmed in Cayman Islands. | |
Community outbreaks confirmed in Switzerland. | |
7 June | First case confirmed in Martinique. |
8 June | First case confirmed in Dominica. |
9 June | First death confirmed in Colombia. |
10 June | First death confirmed in Guatemala. |
First case confirmed in French Polynesia. | |
Community outbreaks confirmed in Guatemala. | |
11 June | The WHO raises its Pandemic Alert Level to Phase 6. |
First case confirmed in the Palestinian Territories. | |
First case confirmed in British Virgin Islands. | |
Community outbreaks confirmed in Hong Kong. | |
12 June | First case confirmed in Morocco. |
First case confirmed in Isle of Man. | |
Community outbreaks confirmed in Uruguay. | |
14 June | First death confirmed in the United Kingdom. |
Community outbreaks confirmed in Philippines. | |
15 June | First death confirmed in Argentina. |
16 June | First case confirmed in Jordan. |
First case confirmed in Qatar. | |
First case confirmed in Samoa. | |
First case confirmed in Sri Lanka. | |
First case confirmed in Suriname. | |
First case confirmed in Yemen. | |
Community outbreaks confirmed in Thailand. | |
17 June | First case confirmed in Monaco. |
First case confirmed in U.S. Virgin Islands. | |
First case confirmed in Netherlands Antilles. | |
First case confirmed in Oman. | |
Community outbreaks confirmed in Malaysia. | |
Community outbreaks confirmed in France. | |
18 June | First case confirmed in Laos. |
First case confirmed in Macao. | |
First case confirmed in South Africa. H1N1 now present in all WHO regions. | |
First case confirmed in Papua New Guinea. | |
First case confirmed in the island of Jersey. | |
19 June | First death confirmed in Australia. |
First case confirmed in Antigua and Barbuda. | |
First case confirmed in Bangladesh. | |
First case confirmed in Ethiopia. | |
First case confirmed in Slovenia. | |
20 June | First case confirmed in Algeria. |
Community outbreaks confirmed in Venezuela. | |
21 June | First case confirmed in Fiji. |
First case confirmed in Brunei. | |
22 June | First death confirmed in the Philippines. |
First case confirmed in Iran. | |
First case confirmed in Montenegro. | |
First case confirmed in Tunisia. | |
First death confirmed in Honduras. | |
23 June | First case confirmed in Latvia. |
Community outbreaks confirmed in Macao. | |
24 June | First case confirmed in Indonesia. |
First case confirmed in Cape Verde Islands. | |
First case confirmed in Côte d'Ivoire. | |
First case confirmed in Cambodia. | |
First case confirmed in Iraq. | |
First case confirmed in Serbia. | |
First case confirmed in Vanuatu. | |
25 June | First human-to-animal transmission of the virus in Argentina. |
26 June | First case confirmed in Lithuania. |
First case confirmed in Guernsey. | |
Community outbreaks confirmed in China. | |
27 June | First case confirmed in Myanmar. |
First case confirmed in New Caledonia. | |
First death confirmed in Thailand. | |
28 June | First death confirmed in Brazil. |
29 June | First death confirmed in Spain. |
First death confirmed in Uruguay. | |
First case of Oseltamivir (Tamiflu) resistance from Denmark found in the world. | |
First case confirmed in Bosnia and Herzegovina. | |
First case confirmed in Kenya. | |
First case confirmed in Mauritius. | |
First case confirmed in Nepal. | |
Community outbreaks confirmed in Italy. | |
Community outbreaks confirmed in Singapore. | |
30 June | First case confirmed in Saint Lucia. |
Community outbreaks confirmed in Egypt. | |
First case of Oseltamivir (Tamiflu) resistance found in Chile. | |
1 July | First case confirmed in Guam. |
First case confirmed in Malta. | |
Community outbreaks confirmed in South Korea. | |
2 July | First death confirmed in Brunei. |
First death confirmed in Paraguay. | |
First case of Oseltamivir (Tamiflu) resistance found in Japan. | |
First case confirmed in Uganda. | |
First case confirmed in Saint Vincent and the Grenadines. | |
3 July | First case of Oseltamivir (Tamiflu) resistance found in Hong Kong, China. |
First case confirmed in Aruba. | |
First death confirmed in El Salvador. | |
4 July | First death confirmed in New Zealand. |
First case confirmed in Croatia. | |
First case confirmed in Macedonia. | |
First case confirmed in Syria. | |
Community outbreaks confirmed in Spain. | |
5 July | First death confirmed in Peru. |
First case confirmed in Palau | |
6 July | First case confirmed in Guadeloupe. |
First case confirmed in Libya. | |
First case confirmed in Saint Martin. | |
First death confirmed in Jamaica. | |
7 July | First case confirmed in Guyana. |
First case confirmed in Belize. | |
First case confirmed in Cook Islands. | |
Community outbreaks confirmed in Portugal. | |
8 July | First case confirmed in Afghanistan. |
First case confirmed in Seychelles. | |
Community outbreaks confirmed in Malta. | |
9 July | First case confirmed in Tanzania. |
Community outbreaks confirmed in Panama. | |
10 July | First case confirmed in Botswana. |
First case confirmed in Réunion. | |
First case confirmed in Zimbabwe. | |
First death confirmed in Bolivia. | |
First death confirmed in Ecuador. | |
First death confirmed in Hong Kong. | |
11 July | First case confirmed in Andorra. |
Community outbreaks confirmed in New Zealand. | |
13 July | Community outbreaks confirmed in Saudi Arabia. |
14 July | First case confirmed in Haiti. |
First case confirmed in Marshall Islands. | |
First case confirmed in Saint Kitts and Nevis. | |
First death confirmed in Puerto Rico. | |
15 July | First case confirmed in Tonga. |
16 July | First case confirmed in Sudan. |
First death confirmed in Singapore. | |
Community outbreaks confirmed in Brazil. | |
Community outbreaks confirmed in Morocco. | |
Community outbreaks confirmed in Colombia. | |
18 July | First death confirmed in Venezuela. |
19 July | First case confirmed in Georgia. |
First death confirmed in Egypt. | |
First death confirmed in Panama. | |
Community outbreaks confirmed in Israel. | |
20 July | First death confirmed in Guam. |
First case confirmed in Albania. | |
First case confirmed in Namibia. | |
Community outbreaks confirmed in Norway. | |
21 July | First case confirmed in Federated States of Micronesia. |
First case confirmed in Northern Mariana Islands. | |
First case of Oseltamivir (Tamiflu) resistance found in Canada. | |
Community outbreaks confirmed in Indonesia. | |
22 July | First death confirmed in Hungary. |
First death confirmed in Laos. | |
First death confirmed in Tonga. | |
Community outbreaks confirmed in India. | |
Community outbreaks confirmed in Ireland. | |
Community outbreaks confirmed in Peru. | |
Community outbreaks confirmed in Vietnam. | |
Community outbreaks confirmed in Jamaica. | |
23 July | First death confirmed in Malaysia. |
First case confirmed in American Samoa. | |
First case confirmed in Bhutan. | |
First case confirmed in Kazakhstan. | |
First case confirmed in Turks and Caicos Islands. | |
Community outbreaks confirmed in Bolivia. | |
Community outbreaks confirmed in Sweden. | |
24 July | Community outbreaks confirmed in Fiji. |
First case confirmed in Falklands Islands. | |
First case confirmed in Gibraltar. | |
First case confirmed in Grenada. | |
First case confirmed in Maldives. | |
25 July | Community outbreaks confirmed in Brunei. |
Community outbreaks confirmed in Ecuador. | |
Community outbreaks confirmed in El Salvador. | |
Community outbreaks confirmed in Greece. | |
Community outbreaks confirmed in Nicaragua. | |
Community outbreaks confirmed in South Africa. | |
Community outbreaks confirmed in Taiwan. | |
First death confirmed in Indonesia. | |
26 July | Community outbreaks confirmed in Cuba. |
Community outbreaks confirmed in Cyprus. | |
Community outbreaks confirmed in Honduras. | |
Community outbreaks confirmed in Paraguay. | |
Community outbreaks confirmed in Turkey. | |
27 July | Community outbreaks confirmed in Denmark. |
Community outbreaks confirmed in Netherlands. | |
Community outbreaks confirmed in United Arab Emirates. | |
First death confirmed in Israel. | |
First death confirmed in Saint Kitts and Nevis. | |
First death confirmed in Saudi Arabia. | |
First case confirmed in Kosovo. | |
First case confirmed in Zambia. | |
28 July | First case of Oseltamivir (Tamiflu) resistance found in Argentina. |
29 July | First case confirmed in Swaziland. |
30 July | First case confirmed in Azerbaijan. |
First case confirmed in Gabon. | |
First case confirmed in Moldova. | |
First death confirmed in Belgium. | |
First death confirmed in France. | |
First death confirmed in Lebanon. | |
First death confirmed in Taiwan. | |
31 July | First case confirmed in French Guiana. |
First case confirmed in Nauru. | |
First death confirmed in Qatar. | |
First case of zoonosis in Brazil, where an infected pig infects a human. | |
2 August | First death confirmed in India. |
3 August | First death confirmed in South Africa. |
First case confirmed in Akrotiri and Dhekelia. | |
First case confirmed in Pakistan. | |
4 August | First case confirmed in Solomon Islands. |
First death confirmed in Vietnam. | |
First death confirmed in Netherlands. | |
5 August | First death confirmed in Iran. |
First case confirmed in Anguilla. | |
6 August | First case confirmed in Ghana. |
First case confirmed in Kiribati. | |
First case confirmed in Liechtenstein. | |
7 August | First death confirmed in Ireland. |
First death confirmed in Palestine. | |
First death confirmed in Samoa. | |
8 August | First case of Oseltamivir (Tamiflu) resistance found in Thailand. |
9 August | Community outbreaks confirmed in Algeria. |
First death confirmed in Iraq. | |
10 August | First death confirmed in Mauritius. |
12 August | First case confirmed in East Timor. |
First case confirmed in Wallis and Futuna. | |
First death confirmed in Nicaragua. | |
First case of Oseltamivir (Tamiflu) resistance found in Brazil. | |
14 August | First case confirmed in Cameroon. |
First case confirmed in Madagascar. | |
First case of Oseltamivir (Tamiflu) resistance found in China. | |
First case of Oseltamivir (Tamiflu) resistance found in Singapore. | |
First case of Oseltamivir (Tamiflu) resistance found in United States. | |
15 August | First case of Oseltamivir (Tamiflu) resistance found in Peru. |
First death confirmed in Japan. | |
First death confirmed in South Korea. | |
First case confirmed in the Democratic Republic of the Congo. | |
17 August | First case confirmed in Mozambique. |
18 August | First death confirmed in Malta. |
First death confirmed in Cook Islands. | |
First death confirmed in Yemen. | |
19 August | First case confirmed in Belarus. |
20 August | First death confirmed in Kuwait. |
First death confirmed in United Arab Emirates. | |
21 August | First cases in birds in the world confirmed in Chile. |
First death confirmed in Oman. | |
22 August | First death confirmed in New Caledonia. |
23 August | First death confirmed in Greece. |
24 August | First death confirmed in French Polynesia. |
First case confirmed in Kyrgyzstan. | |
26 August | |
First death confirmed in Syria. | |
First human-to-animal transmission of the virus in Brazil. | |
First case confirmed in Angola. | |
28 August | First cases in birds confirmed in Brazil. |
29 August | First death confirmed in Bangladesh. |
30 August | First head of state to have swine flu confirmed in Colombia |
31 August | First case confirmed in Djibouti. |
First death confirmed in Sweden. | |
First death confirmed in Bahrain. | |
1 September | First case confirmed in Lesotho. |
First death confirmed in Reunion. | |
2 September | First death confirmed in Macau. |
3 September | First death confirmed in Norway. |
First death confirmed in Marshall Islands. | |
First death confirmed in U.S. Virgin Islands. | |
4 September | First death confirmed in Italy. |
7 September | First death confirmed in Namibia. |
Ecuador's Chief of Presidential Security John Merino dies. | |
First case confirmed in Faroe Islands. | |
8 September | First death confirmed in Suriname. |
9 September | First death confirmed in Madagascar. |
10 September | First case confirmed in Malawi. |
First case of Oseltamivir (Tamiflu) resistance found in Israel. | |
First Oseltamivir (Tamiflu) resistance spread from person to person found in the United States in the world. | |
11 September | First case of Oseltamivir (Tamiflu) resistance found in Australia. |
14 September | First death confirmed in Mozambique. |
15 September | First death confirmed in Solomon Islands. |
17 September | First death confirmed in Luxembourg. |
18 September | First death confirmed in Martinique. |
21 September | Mass vaccinations, which are the first ones in the world, begin in China. |
23 September | First death confirmed in Portugal. |
First death confirmed in Bahamas. | |
25 September | First death confirmed in Germany. |
28 September | First death confirmed in Cambodia. |
29 September | First human-to-animal transmission of the virus in Ireland. |
30 September | First death confirmed in Bulgaria. |
First death confirmed in Barbados. | |
First completed clinical trials by a company for 2009/H1N1 vaccine in the world. | |
Mass vaccinations begin in Australia. | |
1 October | First case confirmed in Saint-Barthélemy. |
4 October | First case confirmed in Tajikistan. |
6 October | First death confirmed in China. |
First death confirmed in Tanzania. | |
10 October | First death confirmed in Cuba. |
12 October | First case of Oseltamivir (Tamiflu) resistance found in Vietnam. |
First death confirmed in Jordan. | |
First case confirmed in Rwanda. | |
First case confirmed in São Tomé and Príncipe. | |
Mass vaccinations begin in Sweden. | |
First human-to-animal transmission of the virus in Norway. | |
13 October | First case confirmed in Mongolia. |
15 October | First death confirmed in Trinidad and Tobago. |
18 October | First death confirmed in Sudan. |
19 October | Mass vaccinations begin in Japan. |
20 October | First death confirmed in Iceland. |
First cases in ferrets confirmed in the United States in the world. | |
21 October | First cases in birds confirmed in Canada. |
First death confirmed in Serbia. | |
Mass vaccinations begin in the United Kingdom. | |
First human-to-animal transmission of the virus in Japan. | |
22 October | First death confirmed in Czech Republic. |
First death confirmed in Guadeloupe. | |
23 October | First death confirmed in Mongolia. |
24 October | First death confirmed in Finland. |
25 October | First death confirmed in São Tomé and Príncipe. |
First death confirmed in Turkey. | |
26 October | First death confirmed in Moldova. |
Mass vaccinations begin in Oman. | |
27 October | Mass vaccinations begin in Canada. |
Mass vaccinations begin in South Korea. | |
First death confirmed in Russia. | |
First human-to-animal transmission of the virus in the Iceland. | |
29 October | First death confirmed in Afghanistan. |
First case confirmed in the Republic of the Congo. | |
First case confirmed in Nigeria. | |
30 October | First death confirmed in Ukraine. |
31 October | First death confirmed in Croatia. |
1 November | Mass vaccinations begin in Ireland. |
Mass vaccinations begin in Kuwait. | |
Mass vaccinations begin in Morocco. | |
2 November | First death confirmed in Austria. |
Mass vaccinations begin in Turkey. | |
3 November | First death confirmed in Belarus. |
First death confirmed in Slovenia. | |
Mass vaccinations begin in Singapore. | |
Mass vaccinations begin in Egypt. | |
First cases in ferrets confirmed in Brazil. | |
4 November | First feline zoonosis confirmed in the United States in the world. |
First case of Oseltamivir (Tamiflu) resistance found in Belarus. | |
First case of Oseltamivir (Tamiflu) resistance found in the Netherlands. | |
5 November | First death confirmed in Saint Lucia. |
First case confirmed in San Marino. | |
6 November | First death confirmed in Slovakia. |
First death confirmed in Pakistan. | |
First human-to-animal transmission of the virus in Hong Kong. | |
7 November | First death confirmed in Sri Lanka. |
Mass vaccinations begin in Belgium. | |
Mass vaccinations begin in Bahrain. | |
Mass vaccinations begin in Saudi Arabia. | |
8 November | First case confirmed in Armenia. |
9 November | First death confirmed in Latvia. |
11 November | First case confirmed in Burundi. |
First case confirmed in Greenland. | |
12 November | Mass vaccinations begin in France. |
First feline zoonosis confirmed in Brazil. | |
13 November | First death confirmed in Cyprus. |
First death confirmed in Poland. | |
14 November | First death confirmed in Kosovo. |
First death confirmed in Switzerland. | |
16 November | First case confirmed in North Korea. |
First case confirmed in Somalia. | |
First death confirmed in Tunisia. | |
First death confirmed in Morocco. | |
First death confirmed in Bosnia and Herzegovina. | |
Mass vaccinations begin in Greece. | |
Mass vaccinations begin in Spain. | |
Mass vaccinations begin in Cyprus. | |
17 November | First death confirmed in Falkland Islands. |
First death confirmed in Maldives. | |
18 November | First death confirmed in Lithuania. |
First death confirmed in Macedonia. | |
First case of Oseltamivir (Tamiflu) resistance found in Finland. | |
First case of Oseltamivir (Tamiflu) resistance found in Slovenia. | |
19 November | First feline death confirmed in the United States in the world. |
20 November | First case of Oseltamivir (Tamiflu) resistance found in the United Kingdom. |
First mutation ( D222G ) confirmed in Norway in the world. | |
First death confirmed in Denmark. | |
Mass vaccinations begin in Jordan. | |
23 November | First death confirmed in Estonia. |
First death confirmed in Romania. | |
Mass vaccinations begin in Netherlands. | |
Mass vaccinations begin in Czech Republic. | |
24 November | First double infection case confirmed in the United States in the world. |
First case confirmed in Montserrat. | |
27 November | First death confirmed in Algeria. |
First double infection case confirmed in South Korea. | |
First mutation ( D222G ) confirmed in France. | |
First case of Oseltamivir (Tamiflu) resistance found in France. | |
28 November | First canine zoonosis confirmed in China in the world. |
First human-to-animal transmission of the virus in Indonesia. | |
First mutation ( D222G ) confirmed in Brazil. | |
30 November | First mutation ( D222G ) confirmed in Finland. |
First mutation ( D222G ) confirmed in Italy. | |
First human-to-animal transmission of the virus in Finland. | |
First double infection case confirmed in Brazil. | |
First death confirmed in Libya. | |
1 December | First death confirmed in Montenegro. |
2 December | First human-to-animal transmission of the virus in the United Kingdom. |
3 December | First mutation ( D222G ) confirmed in Netherlands. [1] |
First death confirmed in Albania. | |
First canine zoonosis confirmed in Brazil. | |
4 December | First mutation ( D222G ) confirmed in Spain. |
7 December | First death confirmed in North Korea. |
9 December | First mutation ( D222G ) confirmed in Macao. |
13 December | First death confirmed in Georgia. |
Mass vaccinations begin in Qatar. | |
14 December | First death confirmed in Armenia. |
15 December | First human-to-animal transmission of the virus in France. |
16 December | First case of Oseltamivir (Tamiflu) resistance found in Germany. |
17 December | First human-to-animal transmission of the virus in Thailand. |
20 December | First completed clinical trials by a company for 2009/H1N1 vaccine in Brazil. |
21 December | First canine zoonosis confirmed in the United States. |
27 December | First death confirmed in Nepal. |
2010 | A(H1N1) Outbreak and Pandemic Milestones |
1 January | Mass vaccinations begin in Malta. |
5 January | Mass vaccinations begin in Brazil. |
11 January | First case confirmed in Mali. |
15 January | Mass vaccinations begin in Peru. |
19 January | First death confirmed in Nigeria. |
20 January | First death confirmed in Bermuda. |
29 January | First case confirmed in Chad. |
3 February | First case confirmed in Mauritania. |
9 February | First case confirmed in Senegal. |
25 February | First case confirmed in Niger. |
27 March | Mass vaccinations begin in Cuba. |
2 April | Mass vaccinations begin in Cambodia. |
12 April | First case confirmed in Guinea. |
26 April | Mass vaccinations begin in the Philippines. |
10 August | H1N1 Pandemic officially declared over. |
Influenza A virus (IAV) is a pathogen with strains that infect birds and some mammals, as well as causing seasonal flu in humans. Mammals in which different strains of IAV circulate with sustained transmission are bats, pigs, horses and dogs; other mammals can occasionally become infected.
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) refers to any strain of the influenza family of viruses that is endemic in pigs. As of 2009, identified SIV strains include influenza C and the subtypes of influenza A known as H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3.
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 1918 Spanish flu pandemic, the 1977 Russian flu pandemic and the 2009 swine flu pandemic. It is an orthomyxovirus that contains the glycoproteins hemagglutinin (H) and neuraminidase (N), antigens whose subtypes are used to classify the strains of the virus as H1N1, H1N2 etc. 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 2009 swine flu pandemic resulted in under 300,000 deaths and is considered relatively mild. These pandemics occur irregularly.
Influenza, commonly known as "the flu" or just "flu", is an infectious disease caused by influenza viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle pain, headache, coughing, and fatigue. These symptoms begin one to four days after exposure to the virus and last for about two to eight days. Diarrhea and vomiting can occur, particularly in children. Influenza may progress to pneumonia from the virus or a subsequent bacterial infection. Other complications include acute respiratory distress syndrome, meningitis, encephalitis, and worsening of pre-existing health problems such as asthma and cardiovascular disease.
The 2009 swine flu pandemic, caused by the H1N1/swine flu/influenza virus and declared by the World Health Organization (WHO) from June 2009 to August 2010, was the third recent flu pandemic involving the H1N1 virus. The first identified human case was in La Gloria, Mexico, a rural town in Veracruz. 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".
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.
The 2009 swine flu pandemic in Canada was part of an epidemic in 2009 of a new strain of influenza A virus subtype H1N1 causing what has been commonly called swine flu. In Canada, roughly 10% of the populace has been infected with the virus, with 428 confirmed deaths ; non-fatal individual cases are for the most part no longer being recorded. About 40% of Canadians have been immunized against H1N1 since a national vaccination campaign began in October 2009, with Canada among the countries in the world leading in the percentage of the population that has been vaccinated. The widespread effect of H1N1 in Canada raised concerns during the months leading to the XXI Olympic Winter Games, which took place in Vancouver in February 2010.
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).
In March and April 2009, an outbreak of a new strain of influenza commonly referred to as "swine flu" infected many people in Mexico and other parts of the world, causing illness ranging from mild to severe. Initial reports suggested that the outbreak had started in February due to farming practices at a pig farm half-owned by Smithfield Foods. Smithfield Foods stated that it had found no clinical signs or symptoms of the presence of swine influenza in the company's swine herd, or among its employees at its joint ventures in Mexico, that it routinely administers influenza virus vaccination to their swine herds and that it conducts monthly testing for the presence of swine influenza. The new strain was identified as a combination of several different strains of Influenzavirus A, subtype H1N1, including separate strains of this subtype circulating in humans and in pigs.
In March and April 2009, an outbreak of a new strain of influenza commonly referred to as swine flu infected many people in Mexico and parts of the United States causing severe illness in the former. The new strain was identified as a combination of several different strains of Influenzavirus A, subtype H1N1, including separate strains of this subtype circulating in humans and in pigs. Spain was the first country in continental Europe to report cases of swine flu, in late April 2009.
The pandemic H1N1/09 virus is a swine origin influenza A virus subtype H1N1 strain that was responsible for the 2009 swine flu pandemic. This strain is often called swine flu by the public media due to the prevailing belief that it originated in pigs. The virus is believed to have originated around September 2008 in central Mexico.
The 2009 Japan flu pandemic was an outbreak of the H1N1 and the Influenza A viruses across Japan. The World Health Organization raised the pandemic alert for influenza to level 4 in April 2009 following a worldwide outbreak of the H1N1 influenza strain. The first Japanese infections of H1N1 and Influenza A were both recorded early in May 2009. In August 2009, the government estimated that the virus strains had infected about 760,000 people. At the height of the pandemic in October 2009, it was estimated that 20% of the Japanese population had been infected and that there were on average more than 20 infected people in each Japanese medical facility. The Ministry of Health, Labor and Welfare reported 198 Deaths as of March 30, 2010. Japan put several measures in place to attempt to control the spread of infection including quarantining air travellers entering Japan who were suspected of having the virus and closing schools in areas of Japan with high numbers of infection. The pandemic ended in August 2010 when the World Health Organization announced that worldwide influenza infection number were back to the seasonal average before the outbreak occurred.
The 2009 swine flu pandemic was confirmed to have spread to the Philippines on May 21, 2009. In the following days, several local cases were reported to be caused by contact with two infected Taiwanese women who attended a wedding ceremony in Zambales.
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 swine flu pandemic in North America, part of a pandemic in 2009 of a new strain of influenza A virus subtype H1N1 causing what has been commonly called swine flu, began in the United States or Mexico.
The 2009 swine flu pandemic vaccines were influenza vaccines developed to protect against the pandemic H1N1/09 virus. These vaccines either contained inactivated (killed) influenza virus, or weakened live virus that could not cause influenza. The killed virus was injected, while the live virus was given as a nasal spray. Both these types of vaccine were produced by growing the virus in chicken eggs. Around three billion doses were produced, with delivery in November 2009.
The 2009 swine 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 the 11th of June 2009, the WHO declared the outbreak to be a pandemic. The overwhelming majority of patients experience mild symptoms, but some persons are at higher risk of suffering more serious effects; such as those with asthma, diabetes, obesity, heart disease, or those who are pregnant or have 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 respiratory failure. Although Ukraine was not (very) affected at first there was on outbreak of the virus in Western Ukraine in early November 2009 that led to the closing of public buildings and cancellation of meetings for three weeks.
2009 swine flu pandemic in Taiwan began on May 20, 2009, when a non-citizen who had been living in Taiwan returned from the United States via Hong Kong. By the end of September, more than 90% of influenza A detected in the community were Influenza A (H1N1).
The 2017–2018 United States flu season lasted from late 2017 through early 2018. The predominant strain of influenza was H3N2. During the spring months of March–May, influenza B virus became dominant.