流行性感冒
Influenza

context: zh_tw: 流感的檢驗方法也不斷持續改進，美國疾病控制與預防中心（CDC）的網站上有提供最新的檢驗資訊摘要。根據 CDC 的資訊，目前的快速篩檢與病毒培養相比，敏感度為 50–75%，特異度則為 90–95%。快速篩檢在流感季節時相當有用，但如果沒有疫情或非流感季節，其效用則不明顯。
en: In children, gastrointestinal symptoms such as vomiting, diarrhea, and abdominal pain, (may be severe in children with influenza B)It can be difficult to distinguish between the common cold and influenza in the early stages of these infections. Influenza symptoms are a mixture of symptoms of common cold and pneumonia, body ache, headache, and fatigue. Diarrhea is not usually a symptom of influenza in adults, although it has been seen in some human cases of the H5N1 "bird flu" and can be a symptom in children. The symptoms most reliably seen in influenza are shown in the adjacent table.The specific combination of fever and cough has been found to be the best predictor; diagnostic accuracy increases with a body temperature above 38°C (100.4°F). Two decision analysis studies suggest that during local outbreaks of influenza, the prevalence will be over 70%. Even in the absence of a local outbreak, diagnosis may be justified in the elderly during the influenza season as long as the prevalence is over 15%.The United States Centers for Disease Control and Prevention (CDC) maintains an up-to-date summary of available laboratory tests. According to the CDC, rapid diagnostic tests have a sensitivity of 50–75% and specificity of 90–95% when compared with viral culture.Occasionally, influenza can cause severe illness including primary viral pneumonia or secondary bacterial pneumonia. The obvious symptom is trouble breathing. In addition, if a child (or presumably an adult) seems to be getting better and then relapses with a high fever, that is a danger sign since this relapse can be bacterial pneumonia.Sometimes, influenza may have abnormal presentations, like confusion in the elderly and a sepsis-like syndrome in the young. Encephalitis due to the flu is rare but not unheard of.
qas: question: zh_tw: 快速篩檢的敏感度是多少？
en: what is the sensitivity of rapid diagnostic test?
answers: zh_tw: text: 50–75%
en: text: 50–75%

context: zh_tw: 遭感染的患者可能會出現打噴嚏或咳嗽的症狀，每次噴嚏或咳嗽會釋出 50 萬顆以上的病毒。當健康的成人遭到感染後，一至一天半後病毒量會急速上升，兩天後達到高峰，病毒量會維持約 5 日左右，但也可能長達 9 日。在人體實驗中，患者的症狀期與可傳染期類似，但可傳染期會較症狀期早一天。兒童的傳染力較成人強，可傳染期約從症狀發生前一天至感染兩週後。免疫力不全的患者可傳染期甚至可長達兩週以上。
en: Influenza, commonly known as the flu, is an infectious disease caused by an influenza virus. Symptoms can be mild to severe. The most common symptoms include: high fever, runny nose, sore throat, muscle pains, headache, coughing, sneezing, and feeling tired. These symptoms typically begin two days after exposure to the virus and most last less than a week. The cough, however, may last for more than two weeks. In children, there may be diarrhea and vomiting, but these are not common in adults. Diarrhea and vomiting occur more commonly in gastroenteritis, which is an unrelated disease and sometimes inaccurately referred to as "stomach flu" or the "24-hour flu". Complications of influenza may include viral pneumonia, secondary bacterial pneumonia, sinus infections, and worsening of previous health problems such as asthma or heart failure.Three of the four types of influenza viruses affect humans: Type A, Type B, and Type C. Type D has not been known to infect humans, but is believed to have the potential to do so. Usually, the virus is spread through the air from coughs or sneezes. This is believed to occur mostly over relatively short distances. It can also be spread by touching surfaces contaminated by the virus and then touching the mouth or eyes. A person may be infectious to others both before and during the time they are showing symptoms. The infection may be confirmed by testing the throat, sputum, or nose for the virus. A number of rapid tests are available; however, people may still have the infection even if the results are negative. A type of polymerase chain reaction that detects the virus's RNA is more accurate.Frequent hand washing reduces the risk of viral spread. Wearing a surgical mask is also useful. Yearly vaccinations against influenza are recommended by the World Health Organization for those at high risk. The vaccine is usually effective against three or four types of influenza. It is usually well-tolerated. A vaccine made for one year may not be useful in the following year, since the virus evolves rapidly. Antiviral drugs such as the neuraminidase inhibitor oseltamivir, among others, have been used to treat influenza. The benefit of antiviral drugs in those who are otherwise healthy do not appear to be greater than their risks. No benefit has been found in those with other health problems.Influenza spreads around the world in yearly outbreaks, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths. About 20% of unvaccinated children and 10% of unvaccinated adults are infected each year. In the northern and southern parts of the world, outbreaks occur mainly in the winter, while around the equator, outbreaks may occur at any time of the year. Death occurs mostly in the young, the old, and those with other health problems. Larger outbreaks known as pandemics are less frequent. In the 20th century, three influenza pandemics occurred: Spanish influenza in 1918 (~50 million deaths), Asian influenza in 1957 (two million deaths), and Hong Kong influenza in 1968 (one million deaths). The World Health Organization declared an outbreak of a new type of influenza A/H1N1 to be a pandemic in June 2009. Influenza may also affect other animals, including pigs, horses, and birds.
qas: question: zh_tw: 人們可以期待咳嗽持續多久？
en: How long can one expect the cough to last for?
answers: zh_tw: text: 兩週以上
en: text: more than two weeks

context: zh_tw: 流感的盛行率在冬天達到高峰，由於北半球和南半球冬天的時間不同，因此事實上流感盛行的時間也不相同。這也是為何世界衛生組織（在國家流行性感冒中心的協助下）每年對南北半球的疫苗配方有不同的建議。
qas: question: zh_tw: 流感在哪個季節最常見？
en: What season does influenza become most common?
answers: zh_tw: text: 冬天

context: zh_tw: 流感為什麼總是季節性爆發而非全年都有一直是個未解之謎。一個可能的解釋是人們冬天時待在室內的時間比較長，因此互相接觸的機會也比較多，這會增加人與人之間傳染的機會；北半球在冬季假期有較多的旅遊活動也可能是原因之一。另一個可能的因素是冬天氣溫較低，因此空氣較乾燥，這會使黏膜水份減少，造成呼吸道無法有效排除病毒顆粒。病毒在低溫的表面也能存活較久，乾冷的環境（小於 5 °C）也更適於水霧傳染，冬天較低的相對溼度有可能是流感季節性傳播的主因。
en: Influenza reaches peak prevalence in winter, and because the Northern and Southern Hemispheres have winter at different times of the year, there are actually two different flu seasons each year. This is why the World Health Organization (assisted by the National Influenza Centers) makes recommendations for two different vaccine formulations every year; one for the Northern, and one for the Southern Hemisphere.A long-standing puzzle has been why outbreaks of the flu occur seasonally rather than uniformly throughout the year. One possible explanation is that, because people are indoors more often during the winter, they are in close contact more often, and this promotes transmission from person to person. Increased travel due to the Northern Hemisphere winter holiday season may also play a role. Another factor is that cold temperatures lead to drier air, which may dehydrate mucus particles. Dry particles are lighter and can thus remain airborne for a longer period. The virus also survives longer on surfaces at colder temperatures and aerosol transmission of the virus is highest in cold environments (less than 5 °C) with low relative humidity. The lower air humidity in winter seems to be the main cause of seasonal influenza transmission in temperate regions.However, seasonal changes in infection rates also occur in tropical regions, and in some countries these peaks of infection are seen mainly during the rainy season. Seasonal changes in contact rates from school terms, which are a major factor in other childhood diseases such as measles and pertussis, may also play a role in the flu. A combination of these small seasonal effects may be amplified by dynamical resonance with the endogenous disease cycles. H5N1 exhibits seasonality in both humans and birds.An alternative hypothesis to explain seasonality in influenza infections is an effect of vitamin D levels on immunity to the virus. This idea was first proposed by Robert Edgar Hope-Simpson in 1965. He proposed that the cause of influenza epidemics during winter may be connected to seasonal fluctuations of vitamin D, which is produced in the skin under the influence of solar (or artificial) UV radiation. This could explain why influenza occurs mostly in winter and during the tropical rainy season, when people stay indoors, away from the sun, and their vitamin D levels fall.
qas: question: zh_tw: 在低溫地區，流感傳播的主要原因是什麼？
en: What is the main cause of transmission of influenza in cool temperate areas?
answers: zh_tw: text: °C）也更適於水霧傳染，冬天較低的相對溼度有可能是流感季節性傳播的主因。
en: text: aerosol transmission

question: zh_tw: 流感在哪個季節最常見？
answers: en: text: winter

context: zh_tw: 流感造成的直接成本來自相關的醫療和生產力喪失，間接成本則來自預防措施。美國每年花費超過 100 億美元在流感上，然而未來的大流行估計會造成更可觀的花費，可能高達上千億的直接或間接支出。過去流感大流行造成的經濟衝擊並未深入研究，一些研究者認為儘管西班牙流感大流行造成勞動人口減少和短期的經濟衰退，但長期而言對人均可支配所得有幫助。其他研究試圖預測一場如 1918 年的流感大流行可能對美國經濟造成什麼影響，估計有 30% 的勞動人口會生病、2.5% 會死亡，30% 的罹病率和罹病期間的三週會使國內生產總值減少 5%，1800 至 4500 萬人感染將使醫療支出大幅增加，預計共將花費 7000 億美元。
en: Influenza produces direct costs due to lost productivity and associated medical treatment, as well as indirect costs of preventative measures. In the United States, seasonal influenza is estimated to result in a total average annual economic cost of over $11 billion, with direct medical costs estimated to be over $3 billion annually. It has been estimated that a future pandemic could cause hundreds of billions of dollars in direct and indirect costs. However, the economic impacts of past pandemics have not been intensively studied, and some authors have suggested that the Spanish influenza actually had a positive long-term effect on per-capita income growth, despite a large reduction in the working population and severe short-term depressive effects. Other studies have attempted to predict the costs of a pandemic as serious as the 1918 Spanish flu on the U.S. economy, where 30% of all workers became ill, and 2.5% were killed. A 30% sickness rate and a three-week length of illness would decrease the gross domestic product by 5%. Additional costs would come from medical treatment of 18 million to 45 million people, and total economic costs would be approximately $700 billion.Preventative costs are also high. Governments worldwide have spent billions of U.S. dollars preparing and planning for a potential H5N1 avian influenza pandemic, with costs associated with purchasing drugs and vaccines as well as developing disaster drills and strategies for improved border controls. On 1 November 2005, United States President George W. Bush unveiled the National Strategy to Safeguard Against the Danger of Pandemic Influenza backed by a request to Congress for $7.1 billion to begin implementing the plan. Internationally, on 18 January 2006, donor nations pledged US$2 billion to combat bird flu at the two-day International Pledging Conference on Avian and Human Influenza held in China.In an assessment of the 2009 H1N1 pandemic on selected countries in the Southern Hemisphere, data suggest that all countries experienced some time-limited and/or geographically isolated socio/economic effects and a temporary decrease in tourism most likely due to fear of 2009 H1N1 disease. It is still too early to determine whether the H1N1 pandemic has caused any long-term economic impacts.
qas: question: zh_tw: 流感造成什麼直接成本？
en: What direct cost does influenza incur?
answers: zh_tw: text: 相關的醫療和生產力喪失
en: text: lost productivity and associated medical treatment

context: zh_tw: 豬流感造成豬隻發燒、昏睡、打呼、咳嗽、呼吸困難和食慾減少，某些狀況下也會造成流產。雖然致死率通常不高，但病毒會讓豬隻體重減輕和營養不良，感染的豬隻在 3－4 周內可減輕 12 英磅（5.4 公斤），進而造成畜牧業的經濟損失。豬流感病毒偶爾能從豬隻直接傳播給人類（稱為人畜共通豬流感），從 20 世紀中葉到 2007 年，約有 50 例人類感染豬流感的紀錄，並造成 6 人死亡。
en: In pigs swine influenza produces fever, lethargy, sneezing, coughing, difficulty breathing and decreased appetite. In some cases the infection can cause abortion. Although mortality is usually low, the virus can produce weight loss and poor growth, causing economic loss to farmers. Infected pigs can lose up to 12 pounds of body weight over a 3- to 4-week period. Direct transmission of an influenza virus from pigs to humans is occasionally possible (this is called zoonotic swine flu). In all, 50 human cases are known to have occurred since the virus was identified in the mid-20th century, which have resulted in six deaths.In 2009, a swine-origin H1N1 virus strain commonly referred to as "swine flu" caused the 2009 flu pandemic, but there is no evidence that it is endemic to pigs (i.e. actually a swine flu) or of transmission from pigs to people, instead the virus is spreading from person to person. This strain is a reassortment of several strains of H1N1 that are usually found separately, in humans, birds, and pigs.
qas: question: zh_tw: 感染豬流感的豬有哪些症狀？
en: What are some symptoms of swine influenza in pigs?
answers: zh_tw: text: 發燒、昏睡、打呼、咳嗽、呼吸困難和食慾減少
en: text: fever, lethargy, sneezing, coughing, difficulty breathing and decreased appetite