2009 flu pandemic
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2009 flu pandemic data
Area Confirmed
deaths Increase in
last 7 days
Worldwide (total) 6,021 +686 (11%)†
European Union and EFTA 292 +54 (18%)
Other European countries
and Central Asia 6 +6 (100%)
Mediterranean and Middle East 181 +31 (17%)
Africa 108 +2 (2%)
North America 1,421 +474 (33%)†
Central America and Caribbean 166 +6 (4%)
South America 2,693 +34 (1%)
Northeast Asia and South Asia 586 +54 (9%)
Southeast Asia 357 +25 (7%)
Australia and Pacific 211 +0 (0%)
Source: ECDC – October 29, 2009[1]
Further information: Cases and deaths by country
†The USA introduced a new reporting system on August 30, 2009.
All lab-confirmed deaths which have occured in the U.S. since
then have been reported together by the ECDC on October 26.
v • d • e
The 2009 flu pandemic is a global outbreak of a new strain of influenza A virus subtype H1N1, termed Pandemic H1N1/09 virus by the World Health Organization (WHO),[2] that was first identified in April 2009. The disease has also been termed 2009 H1N1 Flu by the U.S. Centers for Disease Control and Prevention (CDC),[3] and colloquially called swine flu.
The outbreak was first observed in Mexico, [4][5] with evidence that there had been an ongoing epidemic for months before it was officially recognized as such.[6] The Mexican government soon closed most of Mexico City's public and private offices and facilities to contain the spread of the virus. As the virus quickly spread globally, clinics were overwhelmed by testing and treating patients, and the WHO and the CDC eventually stopped counting all cases and focused instead on tracking major outbreaks. On June 11, 2009, WHO declared the outbreak to be a pandemic.[7]
Only mild symptoms are experienced by the overwhelming majority of victims,[7] but there are exceptions. Some persons are in higher risk groups, such as those with asthma, diabetes,[8][9] obesity, heart disease, children with neurodevelopmental conditions[10], or persons who are pregnant or have a weakened immune system.[11] And there are small subsets of patients, even among young persons previously healthy, in which the patient rapidly develops severe pneumonia, typically 3 to 5 days after initial onset of symptoms. Deterioration can be very rapid, with many patients progressing to respiratory failure within 24 hours, requiring intensive care and ventilation support.[12] And there is a somewhat different pattern in which a child, including a child who is generally quite healthy, seems to be recovering and then relapses with high fever. This can be a secondary infection of bacterial pneumonia, which needs treatment with antibiotics.[13]
Like other influenza viruses, novel H1N1 influenza is typically contracted by inhaling air that has been contaminated by an infected person coughing or sneezing, or by touching one's nose or mouth with hands that have previously touched contaminated surfaces and have not been disinfected.
Symptoms, which last up to a week, are similar to those of seasonal flu, and can include fever, sneezing, sore throat, cough, headache, and muscle or joint pains. To avoid spreading the infection, the CDC recommended that those with symptoms stay home from school, work, and crowded settings; in general, wearing facial masks was not recommended, except in health care settings.[14]
Contents [hide]
1 Historical context
2 Initial outbreaks
2.1 Mexico
2.2 United States
3 Response
3.1 Pigs and food safety
4 Nomenclature
5 Virus characteristics
5.1 Transmission
6 Symptoms and severity
6.1 In adults
6.2 In children
7 Vaccination and prevention
7.1 Travel precautions
7.2 Schools
7.3 Workplace
7.4 Facial masks
7.5 Quarantines
8 Treatment
8.1 Tamiflu and Relenza
8.2 Peramivir
9 Data reporting and accuracy
10 References
11 Further reading
11.1 Schools
12 External links
12.1 Europe
12.2 North America
[edit] Historical context
Annual influenza epidemics are estimated to affect 5–15% of the global population. Although most cases are mild, these epidemics still cause severe illness in 3–5 million people and 250,000–500,000 deaths worldwide.[15] On average 41,400 people die each year in the United States based on data collected between 1979 and 2001.[16] In industrialized countries, severe illness and deaths occur mainly in the high-risk populations of infants, the elderly, and chronically ill patients,[15] although the swine flu outbreak (as well as the 1918 Spanish flu) differs in its tendency to affect younger, healthier people.[17]
In addition to these annual epidemics, Influenza A virus strains caused three global pandemics during the 20th century: the Spanish flu in 1918, Asian flu in 1957, and Hong Kong flu in 1968–69. These virus strains had undergone major genetic changes for which the population did not possess significant immunity.[15][18] Recent genetic analysis has revealed that three-quarters, or six out of the eight genetic segments of the 2009 flu pandemic strain arose from the North American swine flu strains circulating since 1998, when a new strain was first identified on a factory farm in North Carolina, and which was the first-ever reported triple-hybrid flu virus.[19]
The great majority of deaths in the 1918 flu pandemic were the result of secondary bacterial pneumonia. The influenza virus damaged the lining of the bronchial tubes and lungs of victims, allowing common bacteria from the nose and throat to infect their lungs. Subsequent pandemics have had many fewer fatalities due to the development of antibiotic medicines that can treat pneumonia.[20]
20th century flu pandemics
Pandemic Year Influenza virus type People infected (approx) Deaths worldwide (est.) Case fatality rate
Spanish flu 1918–19 A/H1N1[21][22] 33% (500 million)[23] 20 to 100 million[24][25][26] >2.5%[27]
Asian flu 1956–58 A/H2N2[21] ? 2 million[26] <0.1%[27]
Hong Kong flu 1968–69 A/H3N2[21] ? 1 million[26] <0.1%[27]
Seasonal flu Every year mainly A/H3N2, A/H1N1, and B 5–15% (340 million – 1 billion)[28] 250,000–500,000 per year[15] <0.1%[29]
Not a pandemic, but listed to compare the several flu strains endemic in humans which produce seasonal flu with the rare new strain that results in a flu pandemic
The influenza virus has also caused several pandemic threats over the past century, including the pseudo-pandemic of 1947, the 1976 swine flu outbreak, and the 1977 Russian flu, all caused by the H1N1 subtype.[18] The world has been at an increased level of alert since the SARS epidemic in Southeast Asia (caused by the SARS coronavirus).[30] The level of preparedness was further increased and sustained with the advent of the H5N1 bird flu outbreaks because of H5N1's high fatality rate, although the strains currently prevalent have limited human-to-human transmission (anthroponotic) capability, or epidemicity.[21][31]
People who contracted flu before 1957 appeared to have some immunity to H1N1. Dr. Daniel Jernigan of the CDC has stated: "Tests on blood serum from older people showed that they had antibodies that attacked the new virus [...] That does not mean that everyone over 52 is immune, since Americans and Mexicans older than that have died of the new flu."[32]
[edit] Initial outbreaks
Further information: 2009 flu pandemic timeline, 2009 flu pandemic tables, and 2009 flu pandemic by country
Semi-logarithmic plot of laboratory-confirmed A(H1N1) influenza cases in 2009 according to the WHO reports as of 3 August.[33]It is not known where the virus originated.[34][35] Analyses in scientific journals have suggested that the H1N1 strain responsible for the current outbreak first evolved in September 2008, and circulated among humans for several months before being identified as a new strain of flu.[34][36][37]
[edit] Mexico
Further information: 2009 flu pandemic in Mexico
The virus was first reported in two US children in March 2009, but health officials have reported that it apparently infected people as early as January 2009 in Mexico.[38] The outbreak was first detected in Mexico City on March 18, 2009;[39] immediately after the outbreak was officially announced, Mexico requested material support from the US, and within days of the outbreak Mexico City was "effectively shut down".[40] Some countries canceled flights to Mexico while others halted trade. Calls to close the border to contain the spread were rejected.[40] Mexico already had hundreds of cases before the outbreak was officially recognized, and was therefore in the midst of a "silent epidemic".[40] As a result, Mexico was reporting only the most serious cases, possibly leading to a skewed initial estimate of the case fatality rate."[39]
[edit] United States
Further information: 2009 flu pandemic in the United States
The new strain was first identified by the CDC in two children, neither of whom had been in contact with pigs. The first case, from San Diego County, California, was confirmed from clinical specimens (nasopharyngeal swab) examined by the CDC on April 14, 2009. A second case, from nearby Imperial County, California, was confirmed on April 17. The patient in the first confirmed case had flu symptoms including fever and cough on clinical exam on March 30, and the second on March 28.[41] It was not identified as a new strain in Mexico until April 24.[42]
[edit] Response
See also: 2009 flu pandemic by country
Deaths
Confirmed cases
See also: H1N1 live map, WHO updatesOn April 27, the European Union health commissioner advised Europeans to postpone nonessential travel to the United States or Mexico. This followed the discovery of the first confirmed case in Spain.[43] On May 6, 2009, the Public Health Agency of Canada announced that their National Microbiology Laboratory (NML) had mapped the genetic code of the swine flu virus, the first time that was done.[44] In England, the National Health Service launched a website, the National Pandemic Flu Service,[45] allowing patients to self-assess and get an authorization number for antiviral medication. The system was expected to reduce the burden on general practitioners.[46]
US officials observed that six years of worrying about H5N1 avian flu did much to prepare for the current swine flu outbreak, noting that after H5N1 emerged in Asia, ultimately killing about 60% of the few hundred people infected by it over the years, many countries took steps to try to prevent any similar crisis from spreading further.[47][48] The CDC and other American governmental agencies[49] used the summer lull to take stock of the United States's response to the new H1N1 flu and attempt to patch any gaps in the public health safety net before flu season started in early autumn.[50] Preparations included planning a second influenza vaccination program in addition to the one for seasonal influenza, and improving coordination between federal, state, and local governments and private health providers.[50] On October 24, 2009, United States President Obama declared H1N1 flu a national emergency, granting Secretary of Health and Human Services Kathleen Sebelius power to authorize waivers as individual medical facilities request them. More fully, the declaration does "hereby find and proclaim that, given that the rapid increase in illness across the Nation may overburden health care resources and that the temporary waiver of certain standard Federal requirements may be warranted in order to enable U.S. health care facilities to implement emergency operations plans, the 2009 H1N1 influenza pandemic in the United States constitutes a national emergency."[51][52]
[edit] Pigs and food safety
Main article: 2009 swine flu outbreak actions concerning pigs
The novel H1N1 virus is a type of swine influenza, derived originally from a strain that lived in pigs and this origin gave rise to the common name of "swine flu". This term is widely used by mass media. Despite this origin, however, the strain was transmitted between people and not from swine.[6] The United States Secretary of Agriculture made clear that despite its common name being "swine flu", there is no risk of contracting flu from eating cooked pork products.[53] The virus has been found in American[54] and Canadian[55] hogs, as well as in hogs in Northern Ireland, Argentina, and Norway[56]. On April 27, Azerbaijan imposed a ban on the importation of animal husbandry products from America.[57] The Indonesian government halted the importation of pigs and initiated the examination of 9 million pigs in Indonesia.[58] The Egyptian government ordered the slaughter of all pigs in Egypt on April 29, 2009.[59]
[edit] Nomenclature
Further information: Pandemic H1N1/09 virus: Nomenclature
The initial outbreak was called the "H1N1 influenza". The CDC began also referring to it as "Novel Influenza A (H1N1)".[60] In the Netherlands, it was originally called "Pig Flu", but is now called "New Influenza A (H1N1)" by the national health institute, although the media and general population use the name "Mexican Flu". South Korea and Israel briefly considered calling it the "Mexican virus".[61] Later, the South Korean press used "SI", short for "swine influenza". Taiwan suggested the names "H1N1 flu" or "new flu", which most local media adopted.[62] The World Organization for Animal Health proposed the name "North American influenza".[63] The European Commission adopted the term "novel flu virus".[64]
[edit] Virus characteristics
Main article: Pandemic H1N1/09 virus
The virus is a novel strain of influenza, and existing vaccines against seasonal flu provide no protection. A study at the US Centers for Disease Control and Prevention, published in May 2009, found that children had no preexisting immunity to the new strain but that adults, particularly those over 60, had some degree of immunity. Children showed no cross-reactive antibody reaction to the new strain, adults aged 18 to 64 had 6–9%, and older adults 33%.[65][66] It was also determined that the strain contained genes from five different flu viruses: North American swine influenza, North American avian influenza, human influenza, and two swine influenza viruses typically found in Asia and Europe. Further analysis showed that several proteins of the virus are most similar to strains that cause mild symptoms in humans, leading virologist Wendy Barclay to suggest on 1 May 2009 that the initial indications are that the virus was unlikely to cause severe symptoms for most people.[67]
In July 2009, the CDC noted that most infections were mild, similar to seasonal flu, recovery tended to be fairly quick, and deaths to date had been only a fraction of the number of people who die every year from seasonal flu.[citation needed] The 1918 flu epidemic began with a wave of mild cases in the spring, followed by more deadly waves in the autumn, eventually killing hundreds of thousands in the United States.[68] Researchers from the University of Maryland mixed swine flu and seasonal flu and concluded that the swine flu was unlikely to get more lethal.[69]
And, for more regarding the probable or possible history of Novel H1N1, a July 9, 2009, New England Journal of Medicine article states: "H1N2 and other subtypes are descendants of the triple-reassortant swine H3N2 viruses isolated in North America.[70] They have spread in swine hosts around the globe and have been found to infect humans. The segments coding for the neuraminidase and the matrix proteins of the new human H1N1 virus are, however, distantly related to swine viruses isolated in Europe in the early 1990s."[71]
[edit] Transmission
Spread of 2009 H1N1 virus is thought to occur in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing or sneezing by people with influenza. Sometimes people may become infected by touching something – such as a surface or object – with flu viruses on it and then touching their mouth or nose.[72] The basic reproduction number (the average number of other individuals each infected individual will infect in a population that has no immunity to the disease) for the 2009 novel H1N1 is estimated to be 1.75.[73]
[edit] Symptoms and severity
CDC's CAPT Dr. Joe Bresee describes symptoms.The symptoms of swine flu are similar to other influenzas, and may include a fever, coughing (typically a "dry cough"),[74][75] headaches, pain in the muscles or joints, sore throat, chills, fatigue, and runny nose. Diarrhea, vomiting, and neurological problems were also reported in some cases.[76][77] People at higher risk of serious complications include people age 65 and older, children younger than 5 years old, children with neurodevelopmental conditions, pregnant women, and people of any age with underlying medical conditions, such as asthma, diabetes, obesity, heart disease, or a weakened immune system (e.g., taking immunosuppressive medications or infected with HIV).[11] Most hospitalizations in the US were people with such underlying conditions, according to the CDC.[78]
A New England Journal of Medicine article on hospitalized United States H1N1 patients from April to mid-June found that 40% of them had chest X-rays consistent with pneumonia. And if the same pattern holds from the 1957-58 pandemic, then approximately two-thirds of these patients had viral pneumonia and one-third had bacterial pneumonia. However, antiviral medication was received by only 73% of the patients, whereas 97% received antibiotics. It is recommended that such patients receive both.[79]
A study from Australia and New Zealand estimated that the demand for ICU beds due to viral pneumonia was much higher during the pandemic than in previous influenza seasons.[80] A Canadian study reported that intensive care capacity in Winnipeg, Manitoba was "seriously challenged" at the peak of the outbreak, with full occupancy of all regional ICU beds.[80] The average age of ICU patients was 32, 40, and 44 years in Canada, Australia/New Zealand, and Mexico respectively.[80]
[edit] In adults
In adults, shortness of breath, pain in the chest or abdomen, sudden dizziness, or confusion may require emergency care. In both children and adults, persistent vomiting or the return of flu-like symptoms that include a fever and cough may require medical attention.[77] And if it follows the same pattern as in children, a relapse with high fever may in fact be pneumonia.
Dr. Thomas R. Frieden, Director of the CDC,[81] suggests that people with "underlying conditions" who come down with flu symptoms should consult their doctors first before visiting an "emergency room full of sick people," since it "may actually put them in more danger." This was especially true of pregnant women.[11]
[edit] In children
Influenza-associated pediatric deaths reported to CDC, from 2005–06 to start of 2009–2010As with the seasonal flu, certain symptoms may require emergency medical attention. In children, signs of respiratory distress include blue lips and skin, dehydration, rapid breathing, excessive sleeping, seizures,[82] and significant irritability including a lack of desire to be held. Although "too early" to tell for certain, Dr. Frieden has noted that so far the swine flu "seems to be taking a heavier toll among chronically ill children than the seasonal flu usually does." Of the children who have died so far, nearly two-thirds had pre-existing nervous system disorders, such as cerebral palsy, muscular dystrophy, or developmental delays. "Children with nerve and muscle problems may be at especially high risk for complications," the CDC report stated. In children without chronic health problems, it is a warning sign if they seem to recover from the flu but then relapse with a high fever, Dr. Frieden added. The relapse may be bacterial pneumonia, which must be treated with antibiotics.[13]
Researchers in Australia and New Zealand have reaffirmed that infants under the age of 1 year have the highest risk of developing severe illness from swine flu.[80]
[edit] Vaccination and prevention
See also: Influenza prevention, 2009 flu pandemic vaccine, and Influenza vaccine#2009-2010 season (Northern Hemisphere)
The pandemic is expected to peak by mid-winter in the Northern hemisphere.[83] The CDC recommended that initial vaccine doses should go to priority groups such as pregnant women, people who live with or care for babies under six months old, children six months to four years old and health-care workers.[citation needed] In the UK, the NHS recommended vaccine priority go to people over six months old who were clinically at risk for seasonal flu, pregnant women, and households of people with compromised immunity.[46]
Although it was initially thought that two injections would be required, clinical trials showed that the new vaccine protects adults "with only one dose instead of two", and so the limited vaccine supplies would go twice as far as had been predicted.[84] Costs would also be lowered by having a "more efficient vaccine".[84] For children under the age of 10, two administrations of the vaccine, spaced 21 days apart, are recommended.[85][86] The seasonal flu will still require a separate vaccination.[87]
Health officials worldwide were also concerned because the virus was new and could easily mutate and become more virulent, even though most flu symptoms were mild and lasted only a few days without treatment. Officials also urged communities, businesses and individuals to make contingency plans for possible school closures, multiple employee absences for illness, surges of patients in hospitals and other effects of potentially widespread outbreaks.[88]
To combat the virus, the WHO and the US government geared up for a massive vaccination campaign in late 2009, one not seen since Jonas Salk discovered the polio vaccine in 1955.[89]
The Mayo Clinic suggested personal measures to avoid seasonal flu infection were applicable to the 2009 pandemic: vaccination when available, thorough and frequent hand-washing, a balanced diet with fresh fruits and vegetables, whole grains, and lean protein, sufficient sleep, regular exercise, and avoiding crowds.[90] Smoking raises the risk of contracting influenza, as well as producing more severe disease symptoms.[91][92][93][94][95] The leading health agencies stressed that eating properly cooked pork or other food products derived from pigs would not cause flu.[96]
[edit] Travel precautions
Flu inspection on flight arriving in China
Thermal imaging camera & screen, photographed in an airport terminal in Greece. Thermal imaging can detect elevated body temperature, one of the signs of the virus H1N1 (Swine influenza).The WHO stated that containment was not a feasible option and that countries should focus on mitigating the effect of the virus. It did not recommend closing borders or restricting travel.[97] On April 26, 2009, the Chinese government announced that visitors returning from flu-affected areas who experienced flu-like symptoms within two weeks would be quarantined.[98] On May 2, 2009, China suspended flights from Tijuana to Shanghai.[99]
The president of the Association of Flight Attendants told members of a US Congressional subcommittee that all flight attendants should be given training in how to handle a person with flu and help in communicating to passengers the importance of keeping clean hands.[100] She also said that flight attendants need to be provided gloves and facemasks to deal with flu-stricken passengers.[100] Lahey Clinic vice chairman of emergency medicine and Tufts University assistant professor of emergency medicine Mark Gendreau adds that airlines should also ensure that passenger cabins are always properly ventilated, including during flight delays in which passengers are kept aboard the plane. But he also adds that although the aviation industry in the US, along with the CDC, have tried to reassure passengers that air travel is safe, they have so far done too little to try to limit infection risks.[100]
US airlines had made no major changes as of the beginning of June 2009, but continued standing practices that included looking for passengers with symptoms of flu, measles, or other infections, and relying on in-flight air filters to ensure that aircraft were sanitized.[101] Masks were not generally provided by airlines and the CDC did not recommend that airline crews wear them.[101] Some non-US airlines, mostly Asian ones, including Singapore Airlines, China Eastern Airlines, China Southern Airlines, Cathay Pacific, and Mexicana Airlines, took measures such as stepping up cabin cleaning, installing state-of-the-art air filters, and allowing in-flight staff to wear face masks.[101]
[edit] Schools
The examples and perspective in this article may not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page.
The swine flu outbreak has led to numerous precautionary school closures in several countries. Rather than closing schools, the CDC recommended in August that students and school workers with flu symptoms should stay home for either seven days total, or until 24 hours after symptoms subside—whichever is longer.[102] The CDC also recommended that colleges should consider suspending fall 2009 classes if the virus begins to cause severe illness in a significantly larger share of students than last spring. They have additionally urged schools to suspend any rules, including penalizing late papers or missed classes, or requiring a doctor's note, to enforce "self-isolation" and prevent students from venturing out while ill;[103] schools were advised to set aside a room for people developing flu-like symptoms while they wait to go home and that surgical masks be used for ill students or staff and those caring for them.[104]
In California, school districts and universities are on alert and working with health officials to launch education campaigns. Many planned to stockpile medical supplies and discuss worst-case scenarios, including plans to provide lessons and meals for low-income children in case elementary and secondary schools close.[105] University of California campuses were stockpiling supplies, from paper masks and hand sanitizer to food and water.[105] To help prepare for contingencies, University of Maryland School of Medicine professor of pediatrics James C. King Jr. suggests that every county should create an "influenza action team" to be run by the local health department, parents, and school administrators.[106] As of 28 October 2009 (2009 -10-28)[update], about 600 Schools in the United States have been temporarily closed, affecting over 126,000 students in 19 states.[107]
US government officials are especially concerned about schools because the swine flu virus appears to disproportionately affect young and school-age people, between ages 6 months to 24 years of age, making them one of the top priority groups when it comes to the new vaccine. They state that the most important actions are to encourage and facilitate good hand washing and covering coughs and sneezes, flu vaccinations for people at risk; and to separate sick people from healthy people as soon as possible.[108]
[edit] Workplace
The examples and perspective in this article may not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page.
The US Department of Health and Human Services (HHS) and the Centers for Disease Control and Prevention (CDC), with input from the US Department of Homeland Security (DHS), has developed updated guidance[109] and a video for employers to use as they develop or review and update plans to respond to 2009 H1N1 influenza now and during the upcoming fall and winter influenza season. The guidance states that employers should consider and communicate their objectives, which may include reducing transmission among staff, protecting people who are at increased risk of influenza related complications from getting infected with influenza, maintaining business operations, and minimizing adverse effects on other entities in their supply chains.[109]
The CDC estimates that as much as 40% of the workforce, in a worst-case scenario, might be unable to work at the peak of the pandemic due to the need for many healthy adults to stay home and care for an ill family member,[110] and advising that individuals should have steps in place should a workplace close down or a situation arise that requires working from home.[111] The CDC further advises that persons in the workplace should stay home sick for seven days after getting the flu, or 24 hours after symptoms end, whichever is longer.[102] In the UK, the Health and Safety Executive (HSE) has also issued general guidance for employers.[112]
[edit] Facial masks
The CDC does not recommend use of face masks or respirators in non-health care settings, such as schools, workplaces, or public places, with a few exceptions: people who are ill with the virus should consider wearing one when around other people, and people who are at risk for severe illness while caring for someone with the flu.[14] There is general uncertainty among health professionals about the value of wearing either facial masks or more expensive respirators to prevent infection. Dr. Laurene Mascola, Los Angeles County Department of Public Health's director of acute communicable disease control, stated that "masks may give people a false sense of security," and associate professor of medicine at the USC Keck School of Medicine Dr. Paul Holtom stressed that masks should not replace other standard precautions.[113] Masks may benefit people in close contact with infected persons but it was unknown whether they prevent swine flu infection.[113] Yukihiro Nishiyama, professor of virology at Nagoya University's School of Medicine, commented that the masks are "better than nothing, but it's hard to completely block out an airborne virus since it can easily slip through the gaps".[114] According to mask manufacturer 3M, masks will filter out particles in industrial settings, but "there are no established exposure limits for biological agents such as swine flu virus."[113] 3M gained an additional estimated revenue of $80-100 million 2009 in the third-quarter of 2009 from sales of flu prevention products, including face masks, and its face mask manufacturing plants were being run around the clock, with plant expansions being planned.[115]
Despite this, the use of such masks is common in Asia.[116][114] As cases of swine flu were reported in South Korea in April, sales of face masks in the country increased 24% on a year-on-year basis.[117] In Hong Kong, Secretary for Food and Health York Chow said his government has no plans to require riders of public transportation to wear face masks.[118] Masks are particularly popular in Japan, where cleanliness and hygiene are highly valued and where etiquette obligates those who are sick to wear masks to avoid their spreading disease; they are even available in a variety of styles, including high fashion versions.[114] In May 2009, due to high demand, some drug stores in Japan ran out of face masks, even though the country has 42 different manufacturers of them,[114] prompting some to fashion improvised face masks out of other materials; the city of Tatsuno, Hyōgo went so far as to post instructions on creating such a mask on its official website.[119][120] One mask maker reported sales rising sevenfold year-on-year.[114] In response, Shanghai, Tianjin, and Guangdong Province donated masks to Osaka, Kobe, and Hyōgo Prefecture.[121] Taiwan also donated 200,000 masks to Osaka and Hyogo.[122]
[edit] Quarantines
Countries have begun quarantining or have threatened to quarantine foreign visitors suspected of having or being in contact with others who may have been infected. In May, the Chinese government confined 21 US students and three teachers to their hotel rooms.[123] As a result, the US State Department issued a travel alert about China's anti-flu measures and was warning travelers about traveling to China if ill.[124] In Hong Kong, an entire hotel was quarantined with 240 guests;[125] Australia ordered a cruise ship with 2,000 passengers to stay at sea because of a swine flu threat.[126] Egyptian Muslims who went on the annual pilgrimage to Mecca risked being quarantined upon their return.[127] Russia and Taiwan said they would quarantine visitors from areas where the flu is present who have fevers.[128] Japan quarantined 47 airline passengers in a hotel for a week in mid-May,[129] then in mid-June India suggested pre-screening "outbound" passengers from countries thought to have a high rate of infection.[130]
[edit] Treatment
Further information: Influenza treatment
The Mayo Clinic and Medline listed ways to help ease symptoms, including adequate liquid intake and rest, soup to ease congestion, and over-the-counter drugs to relieve pain. Aspirin was a very effective way to treat fever in adults,[131] although in children and adolescents, aspirin is contraindicated due to the risk of Reye's syndrome.[132] While over-the-counter drugs relieve symptoms, they do not kill the virus.[133] Most patients were expected to recover without medical attention, although those with pre-existing or underlying medical conditions were more prone to complications.[134]
[edit] Tamiflu and Relenza
According to the CDC, antiviral drugs could be given to treat those who become severely ill, two of which were recommended for swine flu symptoms: oseltamivir (Tamiflu) and zanamivir (Relenza).[135] To be most useful, they were to be given within two days of showing symptoms and "may shorten the illness by a day or so," according to the Mayo Clinic. To help avoid shortages of these drugs, the CDC recommended Tamiflu treatment primarily for people hospitalized with swine flu; people at risk of serious flu complications due to underlying medical conditions; and patients at risk of serious flu complications. The WHO likewise recommended that Tamiflu only be given to particularly vulnerable people and noted that healthy people who catch mild to moderate cases of swine flu did not need the drug at all.[136] The CDC warned that the indiscriminate use of antiviral medications to prevent and treat influenza could ease the way for drug-resistant strains to emerge which would make the fight against the pandemic that much harder. In addition, a British report found that people often failed to complete a full course of the drug, a behavior which encouraged resistance.[136]
Both medications could have caused side effects, including lightheadedness, nausea, vomiting, loss of appetite, and trouble breathing, and it was recommended that patients discuss possible side effects with their doctor before starting antiviral medication. Children were reported to be at increased risk of self-injury and confusion after taking Tamiflu.[131] The WHO warned against buying antiviral medications from online sources, estimating that half the drugs sold by online pharmacies without a physical address are counterfeit.[137]
Due to the possible development of severe viral pneumonia, the WHO recommended early treatment with antiviral drugs for patients that meet the treatment criteria.[138][139]
[edit] Peramivir
In October 2009, it was reported that the experimental antiviral drug Peramivir had been effective in treating serious cases of swine flu. On October 23, the U.S. Food and Drug Administration (FDA) issued an Emergency Use Authorization for Peramivir, allowing the use of the drug in intravenous form for hospitalized patients only in cases where the other available methods of treatment are ineffective or unavailable;[140] for instance, if tamiflu resistance develops and a person is unable to take Relenza via the inhaled route. Peramivir is currently the only intravenous option for treating swine flu.
Like other anti-flu drugs, Peramivir is a neuraminidase inhibitor;[141]
[edit] Data reporting and accuracy
See also: GISAID, National Influenza Centers, Disease surveillance, and Clinical surveillance
The initial outbreak received a week of near-constant media attention. Epidemiologists cautioned that the number of cases reported in the early days of an outbreak can be very inaccurate and deceptive due to several causes, among them selection bias, media bias, and incorrect reporting by governments. Inaccuracies could also be caused by authorities in different countries looking at differing population groups. Furthermore, countries with poor health care systems and older laboratory facilities may take longer to identify or report cases.[142] Dr. Joseph S. Bresee (the CDC flu division's epidemiology chief) and Dr. Michael T. Osterholm (director of the Center for Infectious Disease Research) have pointed out that millions of people have had swine flu, usually in a mild form, so the numbers of laboratory-confirmed cases were actually meaningless, and in July 2009 the WHO stopped keeping count of individual cases and focused more on major outbreaks.[143]