Chinese Social Media Reaction to Information about 42 Notifiable Infectious Diseases.

This study aimed to identify what information triggered social media users’ responses regarding infectious diseases. Chinese microblogs in 2012 regarding 42 infectious diseases were obtained through a keyword search in the Weiboscope database. Qualitative content analysis was performed for the posts pertinent to each keyword of the day of the year with the highest daily count. Similar posts were grouped and coded. We identified five categories of information that increased microblog traffic pertaining to infectious diseases: news of an outbreak or a case; health education / information; alternative health information / Traditional Chinese Medicine; commercial advertisement / entertainment; and social issues. News unrelated to the specified infectious diseases also led to elevated microblog traffic. Our study showcases the diverse contexts from which increased social media traffic occur. Our results will facilitate better health communication as causes underlying increased social media traffic are revealed.


Introduction to the Supplemental Online Appendix
The Supplemental Online Appendix provides the results of the qualitative content analysis of Weibo posts containing the keyword for each infectious disease included in our paper. Each section follows the same format: first, a figure of the time series of the daily count of Weibo posts that contained the specified keyword; second, the date of the peak for which we performed the content analysis; third, sample Weibo posts that were representative of the posts of the peak, as well as the count and categories of Weibo posts that they represented. The order in which the diseases are presented follows the list of the Law of the People's Republic of China on Prevention and Treatment of Infectious Diseases (中华人民共和国传染病 防治法), as of 2012 [1]. For an official English translation of the Law, see reference [2]. Viral hepatitis is counted as one disease in the law, but we counted Hepatitis A, B, C and E separately following the disease reporting scheme of the Chinese Center for Disease Control and Prevention. Notes: The user IDs of Weibo users in our database had been anonymized and replaced by random numbers. If they appeared in the Weibo posts, they are either deleted from the presentation below, or they are printed as @ [user]. Sometimes, @[user1], @[user2] etc., are used to distinguish one user from another in the same Weibo post (for example, in a repost of a repost of a Weibo post). Figure S1. Daily count of Weibo posts with the keyword for "Plague" (鼠疫) in 2012 among Sina Weibo users with 1000 followers or more Content analysis was performed for Weibo posts generated on the peak date of January 27, 2012.  食、喝开水、洗净手"，就不会感染 霍乱病。 pay attention to maintain personal hygiene and practice "eating cooked food, drinking boiled water, washing hands", you will not be infected with cholera. Haiti, its reconstruction after the earthquake and its cholera prevention efforts.

(4%)
#维和影像#【海地，别哭】海地强 震发生两年多后，灾区仍有近 50 万 人在临时搭建的庇护帐篷营地居 住。作为世界上最不发达国家之 一，该国失业率仍超过 60％。持续 减少的人道主义救援资金对海地重 建进程造成了严重威胁，尤其体现 在霍乱病的防治方面。刚刚又遭受 热带风暴袭击，海地经济社会发展 更是雪上加霜。 #Peace-keeping image# "Haiti, don't cry" Since the Haitian strong earthquake happened more than two years ago, there are still about 500,000 people living in tents in temporary settlements. Among one of the least developed countries, Haiti's unemployment rate is over 60%. The continual decrease of humanitarian aid is a severe threat to the reconstruction process in Haiti, especially in the prevention and treatment of cholera. The recent hurricane has made the economic and societal development of Haiti even worse.

(4%)
Original Weibo post About Haiti flood. He also prepared 100 coffins, of which 99 were reserved for the corrupt government officials and one for himself. He is the famous premier -Zhu Rongji. Beijing that led to many injuries and deaths on July 21, 2012. As many people suspected that the government was covering up the actual number of victims of the floods, the Beijing Municipal Government held a press conference on July 24 and declared that they would release the official data as quickly as possible. The director of the press office of the Beijing Municipal Government also said that having experienced the challenge of SARS ("Fei-dian"), they would never cover up the case count of injury and death again.

SARS
Another 41 posts could be classified as personal comments or recollection of personal experiences. Weibo users recollected their own experiences of disasters including SARS in 2003. I have lived 20 years, having experienced a drought that was 1 in 50 years, a snow storm that was 1 in 60 years, a flood that was 1 in 100 years, a mudslide that was 1 in 300 years, an earthquake that was 1 in 500 years, a tsunami that was 1 in 600 years, and also solar eclipses, lunar eclipses and meteors…. Facing SARS, I attended primary school, stepping on avian flu, I attended lower middle school; taking the risk of influenza A, I attended upper middle school; now I attend university, someone said that 2012 is the end of the world! What a spectacular lives we have… 41 (19%) http://tieba.baidu.com/p/182348 9513

Personal comments
Posts that were not related to SARS

(2%)
Original Weibo post * *Note: Our keyword for SARS was "Fei-dian", which is the short form of Fei-dian-xing Fei-yan, atypical pneumonia. As we did not perform tokenization process of the Chinese Weibo text, our search algorithm returned any posts that contained the term 非典型 "Fei-dian-xing" (atypical).

HIV/AIDS Figure SDaily count of Weibo posts that contained the keyword for HIV/AIDS (艾滋) in 2012 among Sina Weibo users with 1000 followers or more.
Content analysis was performed for Weibo posts that were generated on the peak date of December 1, 2012. The majority of the posts were related to health education/information, for example, introducing World AIDS Day (n=474); carrying the slogan for "Striving towards zero AIDS" (n=85); educating the public on the origin of World AIDS Day (n=55); advocating the removal of discrimination against HIV/AIDS patients (n=53); providing information related to HIV transmission among men who have sex with men (n=50); describing the routes of HIV transmission (n=48); mentioning World AIDS Day as "Today in history" (n=33); explaining what AIDS is (n=23); and explaining that the proper use of condoms is an effective means to prevent HIV transmission (n=22). Weibo posts are also means to promote other health promotion events, for example, an interactive health education activity (n=17); and a health promotion activity that gives away condoms (n=17).
We also identified posts that describe HIV/AIDS statistics, including UN global estimates (n=22), China's national estimates on male homosexual transmission (n=50), and national HIV estimates (n=15). There were also posts that provided statistics from various provinces and municipalities, including Zhejiang Province Some Weibo posts discussed HIV-related social issues. For example, some remembered the renowned gynaecologist and AIDS activist Dr. Gao Yaojie who was forced to leave China for the United States in 2009 (n=32); some discussed the discrimination faced by HIV patients when they look for employment opportunities (n=25).
Based on our data, it was apparent that World AIDS Day 2012 successfully drew the attention of Chinese netizens, as represented by our dataset of users who had 1000 or more followers. Furthermore, World AIDS Day 2012 was a health promotion campaign that encompassed many events and activities across China.
Our data demonstrated that there was no single event or news article or Weibo post (and its reposts) that dominated the entire Weibo conversation about World AIDS Day 2012. There was a diversity of Weibo contents about HIV/AIDS on World AIDS Day 2012. "Striving towards zero AIDS Special report" It is 8am, December 1, 2012. Good morning, everyone! Today is the annual World AIDS Day. Now we are formally beginning "@[user] #Towards Zero AIDS #Special report". At a frequency of 30 minutes, we will cover information of December 1 for you at every angle. Volunteers of this program will report on the street. Repost information of this post within today will have an opportunity to win a prize.  (1) What is AIDS? The full name is Acquired Immunity Deficiency Syndrome. It is an infectious disease caused by the Human Immunodeficiency Virus. This virus primarily damages the human immune system. After the immune system is damaged by the virus, the human body will be infected with other diseases due to the loss of immunity and this will eventually lead to death. has just got married brought his wife to the clinic. He complained of frequent urination, urinary urgency and pain during urination. The diagnosis was "honeymoon disease". The advice given was to drink more water and to avoid sexual intercourses. A few days later, we met again. I asked, "Recovered?" My friend was frustrated and said, "My wife has sore throat and hoarseness. The doctor smiled and said, "Relocated," and advised, "To prepare with Gangtai". These posts were predominately single Weibo posts that we did not group together as the aforementioned posts.
* The category with an asterisk (*) means that those Weibo posts share the same meaning with some Weibo posts with some textual differences. The sample post presented is a representative one.  [3] for a hepatitis A outbreak associated with green onions in Pennsylvania, USA). We also found that the 17 posts mentioning "hepatitis A" on January 14, 2012 were all reposts of that post. Together, they formed one "peak" created by re-posting one post. And this post has been re-posted multiple times from early January to late 2012.

Hepatitis
On January 13, 2012, there was a Weibo post that was re-posted twice (as observed in our dataset): "I said it once more, for the sake of the kids, domestic (i.e. China-made) products of calcium supplements with dairy ingredients, and cod liver oil, should not be given to the kids. Also, [even though] vaccine produced domestically is free, one should not take it, especially, the Encephalitis B vaccine and the Hepatitis A vaccine." This post expressed the lack of consumer's confidence in China-made health-related products. Two posts in our dataset on Jan 13, 2012 were re-posts of this post. Each of them included the microblogger's own comments. One wrote, "What can we do? The humble poor people cannot afford imported products." Another wrote, "For the sake of the kids, switch!" This is an example showing that the mistrust of certain healthcare products (including vaccines) by many Chinese citizens should be understood as part of a general mistrust of the quality control of Chinese products from infant formulas to vaccines.   There was also a Weibo post (and one re-post) that provided a link to a Tudou (the Chinese equivalent of YouTube) video that was a news program. The first part of the news program was about a hepatitis B virus carrier trying to promote the knowledge of the proper routes of transmission of hepatitis B, by asking passersby to kiss her hand. She waited for 10 minutes before a passersby was willing to do so (Video: http://t.cn/zO2SiRy).  According to the reporter, personnel from the Communist Committee of Zijin County tried to offer bribes to cover it up. After being rejected by the reporter, they tried to block the article to appear in print via various means (see Weibo post in the Table below). Eventually, after two months, the news article finally went in print and the news was covered by major newspapers in China, including the People's Daily. Weibo posts of news articles about this outbreak were then re-posted by many (n=92).     Summary: Of the 11 Weibo posts that mentioned "poliomyelitis" on December 15, 2012, seven mentioned a so-called "World Strengthened Immunity Day". What is written in Chinese as "Strengthened Immunity Day" is known as National Immunization Days (NIDs) or supplementary immunization activities (SIAs) in WHO's parlance. This is intended to supplementnot replaceroutine immunization. National Immunization Days are conducted in two rounds, one month apart (see reference: http://www.polioeradication.org/Aboutus/Strategy/Supplementaryimmunization.aspx, accessed June 9, 2014). In mainland China, the National Immunization Day was conducted on December 5 and January 5.
While the National Immunization Days are part of WHO strategy to eradicate polio globally, there is no such event known as "World Strengthened Immunity Day" listed in the list of World Health Assembly mandated health days (reference: http://www.who.int/mediacentre/events/official_days/en/, accessed June 9, 2014). However, in Chinese mass media, as in the online discussion of Chinese netizens, there are many instances in which such an event "exists". ). This so-called "World Strengthened Immunity Day" even has its own Baidu Baike (Baidu Encyclopedia) page, listing it as one of the "International Days" (http://baike.baidu.com/view/21469.htm, accessed June 9, 2014). No reliable sources were cited in any of these websites. While the 41 st World Health Assembly (1988) has resolved to eradicate polio and national immunization days are one of the means to achieve that goal, the WHA did not specify December 15 th as a so-called "World Strengthened Immunity Day" (See: http://www.polioeradication.org/content/publications/19880513_resolution.pdf, accessed June 10, 2014).
We can interpret this phenomenon as an interesting Chinese adaptation of NIDs and to promote it as an international day. By having it mis-understood / misinterpreted (or even fabricated) as an international health day mandated by WHA, the Chinese authorities managed to convince the average Chinese citizen that the NIDs have international mandate (which they do have) and can encourage citizens to get vaccinated. We decided to classify these posts health information, instead of alternative health information.
Of the eleven Weibo posts, there were another four posts about the implementation of the National Immunization Day in a Chinese city. After birth, at the age of 2 nd , 3 rd and 4 th month, one has to take this type of poliomyelitis "sugar pill".

Avian influenza Figure SDaily count of Weibo posts with the keyword for "Avian influenza" (禽流感) in 2012 among Sina Weibo users with 1000 followers or more.
Content analysis was performed for Weibo posts generated on the peak day of January 2, 2012. Paying closer attention to these comments, we can have a glimpse of a variety of online reaction towards the avian influenza incident. One Weibo user recommended "eating less chicken and ducks; also not having meals at Kentucky Fried Chicken." ("少吃鸡鸭吧，肯德基也别吃了"). One user asked, "There is someone who died of complications of avian influenza in Shenzhen.
[China] CDC said that the virus has not mutated to become transmissible between humans. Should we believe in what you [China CDC] say?" ("深圳有人因禽流感引發併發症死亡，疾控中心說病毒沒變種至人傳人。究竟信不信你好？") One hoped that it would end soon ("希望到此为止"); another was worried ("刚刚新闻说深圳有禽流感，担心。"); and someone asked, "What good, advanced and wonderful ways to prevent avian flu do you have?" ("防治禽流感，您有什么好招、高招和妙招？"). But there was also a user who was not worried: "It was really cold tonight. I have just had a meal of wild game … [a list of dishes]… It was really good. Who care about SARS and avian flu? Let's satisfy the appetite first!" ("今晚夠冷，吃了頓野味宴，有炆菓子狸，山豬，炒黃猄肉，燒大鱔，班鳩鯪魚肉飯，飯鏟頭蛇湯，黃金蝦，各類有機菜，真是正絶，什麼沙 士禽流感均拋諸腦外，大快朶頤才算！") The first time to learn that chicken will get these diseases that seem to me that only people will get… //@[user]leukemia plus tracheitis?! Sounds more dreadful than avian flu.   Of the 70 posts on the peak date of June 21, 2012, 67 (96%) were "false positives" as they were counted due to the pseudonym @u3JH1N1HY (the random number generated to replace a username) contained the numeral-letter combination of "H1N1". Therefore, we did not count it as a real peak and we moved on to analyze the data on March 12, 2012.

Peak Date: March 12, 2012
Total count: 42 Of the 42 Weibo posts mentioning "H1N1" that were generated on March 12, 2012, 37 posts were about the outbreak of influenza A(H1N1) among students in Hotan, Xinjiang. There were news reports (n=29), health education materials (n=5) and personal comments (n=3).  All 141 Weibo posts on August 30, 2012, that contained the term "measles" ("麻疹") were actually about urticaria (commonly known as hives) and not about measles. In Chinese, urticaria is known as "荨麻疹". The Chinese medical term for urticaria "荨麻疹" contains "麻疹" (measles) as its second and third characters.
Therefore, we moved on to analyze the peak on January 4, 2012.
Total count: 77 Summary: There were 77 Weibo posts that mentioned "measles" (麻疹) on January 4, 2012. Of them, 68 were posts and re-posts of health information provided by a commercial company that mentioned four diseases that have symptoms similar to common cold. Another 5 Weibo posts were related to alternative health information (n=3), health information (n=2) and traditional Chinese medicine (n=1).
There were 4 posts that were related to urticaria, not measles. Indigowoad root has the effects of detoxification. It has a better preventive and treatment effects on common diseases such as cold, flu, mumps, conjunctivitis, and measles. However, a minority of people think that indigowoad root powder is a "benign drug". Whether one is ill or not one would take two packets. This is not correct. 4 different posts about urticaria Not applied * One of the reposts was a modification of the original post with the last section about "mumps" deleted. That explains why the count of this Weibo post and reposts was 68 for "measles" and was 67 in the section on "mumps".   Only 7 of these 692 Weibo posts were genuinely related to health information or personal experience that was somehow related to rabies. Four posts were about an article on the "high cost but low effectiveness" rabies prevention program in China. One post was about keeping pets with kids and mentioned rabies. Another post was about the user's personal experience of being bitten by a dog and afterwards receiving the vaccine against rabies. Another post was about the story of Pasteur.

Epidemic hemorrhagic fever
The other posts were derogatory uses of the Chinese term for rabies to criticize or abuse other people. These include a comment on news of a university student carried by an old lady to class (n=6), a comment on animal right activists (n=2), and curses (n=2).    Figure S16. Daily count of Weibo posts with the keyword for "dengue" (登革热) in 2012 among Sina Weibo users with 1000 followers or more.
Content analysis was performed for Weibo posts generated on the peak date of September 9, 2012. Summary: Of the 36 Weibo posts that contained the keyword for "dengue" (登革热) on September 9, 2012, they were all commercial advertisements (and reposts thereof) for a promotional event for tourism in Thailand that provided mosquito repellent cream as a gift to prevent dengue.      , 90 were about a child torture case. The kindergarten teacher who allegedly tortured certain children, facing the compensation requests made by the parents, pleaded for mercy as her father suffered from tuberculosis and her mother had mental disability.
Another 5 posts mentioned that persimmon tea was good for the health of tuberculosis patients.   (Table S20A).
Since the majority of the posts were not related to typhoid or paratyphoid, we considered the peak of August 18, 2012, as a "false positive". We therefore, moved on to analyze the next peak. Summary: Of the 29 Weibo posts created on September 21, 2012, that mentioned the keyword for "typhoid" (伤寒), 16 posts were related to a media report in 2010 about the vending machine selling "dirty water", an advertisement in World Water Week 2010 for UNICEF's Tap Project. It is interesting to observe that even a Weibo post that mentioned an "old" news could still attract people's attention and so they reposted it. There were another 13 posts that were related to the "danger" of poor-quality napkins in restaurants (Table S20B). "The danger of napkins in restaurants" Nowadays, restaurants provide free napkins. However, there is a hidden danger in some napkins. Experts say that napkins of poor quality contain various types of fungi, Escherichia coli, Mycobacterium tuberculosis, hepatitis virus, and will easily lead to disease such as enteritis, typhoid, dysentery and hepatitis. The bleaching additives in napkins contain carcinogenic chemicals, such as heavy metal cadmium in fluorescent brightener, which can damage the circulatory system and memory.

(45%)
This is a post that has been circulated in a variety of websites and social media platforms. Figure S21. Daily count of Weibo posts that contained the designated keywords for epidemic meningitis. We used three keywords for detection: 1) 脑膜炎 (Nǎomó yán) (grey line), 2) 脑脊髓膜炎 (Nǎo jǐsuǐ mó yán) (black line) and 3) 流脑 (Liú nǎo) (red dotted line). We found that the daily number of Weibo posts that carried the second and third keywords was smallzero in most daysand the maximum daily count in 2012 for the second keyword is 9 and the third keyword is 15. For our content analysis, we focus on the peak for the first keyword.

流脑 (Liu nao)
Summary: Of the 1485 Weibo posts generated on August 18, 2012 that mentioned the keyword for meningitis (脑膜炎), 1475 (99.33%) were about a story about a young girl who was taken to the hospital by her parents. In a nutshell, the child was first diagnosed with suspected meningitis and was prescribed lumbar puncture to confirm or exclude the diagnosis of meningitis. And then, when the parents took the child to another department of the same hospital for the procedure, there was miscommunication between the two departments. At the end, the parents lost faith in the doctors and withdrew their consent to their daughter's lumbar puncture. They then took her to another hospital for a second opinion. The doctor there diagnosed her as not having meningitis (without lumbar puncture). The father wrote a long essay and posted it to his Weibo account as a long Weibo post (Chinese title: 杨娃娃腰椎穿刺惊魂). That post triggered an avalanche of responses on Weibo.
We identified 617 posts (41.55% of 1485) that shared similar experiences of themselves or their family or other people. The comment made by one famous writer attracted many reposts (n=479). Another famous writer's critique of that post drew many reposts too (n=161). Many criticized the doctors (n=81) and some criticized the hospital by name (n=22). Some supported the doctors and their decision to prescribe a lumbar puncture (n=41). Some appeared relatively neutral and saw the merits of both sides (n=33).
This incident provided an interesting example that demonstrated the power of Weibo to amplify the experience of one patient and her parents that drew the attention of many. The underlying social problem of the tension and mistrust between patients and the medical profession in China is the root cause of this phenomenon. Many found themselves in a similar situation. They also wanted to share their experience. They did so by re-posting the original post. The fact that certain famous writers (and Weibo opinion leaders) commented on the incident further amplified the original "signal".    In October 2012, ACIP recommended all pregnancy women to receive Tdap (tetanus, diphtheria and pertussis) 3-in-1 vaccine among pregnancy women. A Chinese hospital took the opportunity to emphasize that this recommendation was also practiced by them. It is interesting to note that CDC statistics about the resurgence of pertussis cases in the US was quoted directly from the CDC press release. However, the Weibo quote did not mention that the case count statistics was for the US only.         * Note: Even though the same keyword 淋病 appear in the posts, the words here actually mean something entirely different from gonorrhea. This is an example that nuances in language may reduce the specificity of our detection methods. Figure S28. Summary: There were 207 Weibo posts containing the keyword for "syphilis" (梅毒) on August 4, 2012. Of these, 168 were related to a case of denial civil servant employment due to a positive syphilis test. Tang Haiqing ranked number one for a Chinese government position that she applied. Unfortunately, she was repeatedly tested positive for syphilis in hospitals specified by the authorities. However, when she sought independent tests from other hospitals, she was found negative. She posted her negative results online and was rebutted by her Communist Party superior.

Syphilis
Another 39 posts were about a case of an elderly who had been tested for syphilis and HIV 6 times during his episodes of hospitalizations. * Xuandiao Sheng (选调生) are the elite recruits of the Chinese government. They are university graduates with high levels of academic achievements and political loyalty. Compared to regular civil servants, they are on a fast track in their career progression. After a number of years of training experiences on the grass-root level, they will soon be promoted to higher levels of administration in the government. Figure S29.   A man who had his spleen removed due to schistosomiasis found his left kidney "gone missing". The surgeon responsible for the surgery said that the patient actually had a congenital unitary kidney. It was the tension between the patient and the surgeon that drew the attention of many netizens. We classify this under the category of social issue.  Figure S31.    87%) were about the movie "2012". The day before (December 7) was the Kamaishi earthquake that generated a tsunami that hit Miyagi Prefecture, Japan. It so happened that in the movie "2012", it also suggested that Japan would experience an earthquake on December 7, 2012. People were so intrigued by this and therefore they discussed whether the story line of the movie, that included an outbreak of influenza in Europe, would really come true in the real world. This is another example that diseasespecific keyword search in Weibo or Twitter may not necessarily help us obtain posts/tweets that are really about that disease.

Malaria
For the remainder of the posts, we identified many posts about influenza prevention. Some provided health information on various topics, such as statistics of zoonotic diseases (n=3), maternal and child health (n=1), germs on a mobile phone (n=1), common cold (n=1), common diseases in autumn and winter (n=1).
However, many posts contained alternative health information, according to our categorization. There were posted about dietotherapy; health effects of various types of food and tea. One post suggested that using vinegar as nose drops to prevent influenza infection. Another post suggested that consumption of curry helps the Indian people prevent influenza infection. Our observation can serve as a starting point for future research in social sciences to understand how these pieces of mis-information are circulated in social circles and online.
Three posts described personal experiences of influenza-like illness: either current experience (n=1), past experiences (n=1), or one's kid's experience (n=1). Two other post were personal comments. There were five posts that were advertisements.
Lastly, there were sixteen posts that were not related to influenza. They were picked up by our keyword search, due to the issue of tokenization of Chinese texts. Texts that contained the characters for 流感 but were unrelated to influenza were picked up by our algorithm. Future improvement of algorithm may resolve this issue. Wu# 美丽依旧 更多美图 http://t.cn/zjJSnvS "December 7, 2012 #Star Trek#" #kristen stewart#'s movie #Road# will be released in a small group of theaters in the US on December 21. The early stage promotion activity of this movie has also begun recently.
Even though she was absent from #OTR#'s Q&A activity because of severe flu, but she was very dediated and still attended a private screening in LA despite she was sick. "The prevention of diseases that are common in autumn and winter" 1. Influenza: The typical flu symptoms are fatigue, headache, dizziness, body aches; often with sore throat, nasal congestion and a running nose. 2. Rhinitis: The patient will have nasal congestion, a running and itchy nose, throat irritation, and cough. 3. Asthma: The patient is prone to respiratory infections in the cold season. 4. Bronchitis: When the temperature dips, the small blood vessels of the respiratory tract may suffer from spasm and ischaemia. The immune defense funcation may decrease and leads to illness.   "The attack of influenza is coming. Little clever tricks to prevent common cold in autumn and winter" 1. To bath your feet in hot water for 15 minutes every night; 2. To eat raw spring onions with cold dishes; 3. To gargle with slightly salted water every morning, every night and after meals; 4. To use cold water to wash yoru face every day; 5. To massage your nasal groove regularly; 6. To use baijiu to brush the body; 7. To rub your nose with spring onions to cure nasal congestion; 8. To blow against your temple with hot air for 3-5 minutes, using an electric hair dryer; 9. To take one tablespoon of mashed garlic with honey; 10. To take an egg with sesame oil every morning and every night; 11. [ #Pteridium aquilinum# relieves the "heat" toxin. Frequent consumption helps prevent influenza ] An element in Pteridium aquilinum has a certain inhibitory effect against bacteria. It is effective against bacteria and inflammation. It helps resolve the phlegm and has the effect of detoxication. Frequent consumption can effectively prevent influenza. Little tips: Boil it in water for a while before consuming fresh Pteridium aquilinum. This will remove the sticky substances and the smell of the soil from the surface of the Pteridium From the perspective of the intellectual development of neonates, babies and young children, neonates that were born in winter are more in need of swimming to exercise the limbs, to facilitate the brain and the central nervous system to develop to maturity, to strengthen the body, to raise the human immune capacity, which is a "good helper" to help kids defend against flu. http://t.cn/zjfTwpC "Vinegar as nose drop and in fumigation" Dilute vinegar with cold water as 5% -10% solution and use it as nose drops, 4-6 times a day, with 2-3 drops per nostril. It has a very good treatment effect against common cold and influenza. Especially in the early phrase of common cold, its treatment effect is even better. Vinegar can kill the common cold virus hidden in the nasopharynx. During an influenza epidemic, using vinegar as nose drops has a reliable preventive effect. * Our keyword search picked up 16 posts that were not related to influenza. Fifteen contained the term "潮流感" (Cháoliú gǎn), which means trendy. One contained the term "交流感情" (Jiāoliú gǎnqíng), which means communication or exchange of emotions. In both cases, 流感 (liú gǎn; flu) were part of it and so these Weibo posts that were unrelated to influenza were picked up. To better increase the precision (positive predictive value) of our algorithm in future studies, we will need to perform a tokenization procedure of the Chinese text before the keyword search. Figure S33.  That person has gone. How can one find her? When I was an in-patient, only she could find me. I could never locate her. She claimed that she was too busy to pick up the phone! Also, there was one thing: My friend's kid had a fever due to common cold. It so happened that the kid was there in the hospital seen by that doctor. So, the kid was misdiagnosed by her to have mumps. Originally my friend wanted to take the kid to the USA. However, he feared that it may get worse or may infect others, and so the kid did not go. Later, they visited another hospital. The kid was prescribed some medication. After a few days, the kid recovered.   Figure S35. Another 3 posts listed 8 situations when contact lens should be worn. One of which was "In Spring, wearing contact lens may easily lead to allergic conjunctivitis".

Conjunctivitis
There were 4 other posts that mentioned 3 acupuncture points on the thumb can help relieve eye symptoms, including acute conjunctivitis.  Another twelve were comments on this event, of nine were complementary. Of these, eight mentioned "Helping kids with leprosy, eleven years as a day. If we can persist for 10 years, China for sure will become a more open, transparent and egalitarian." (See Table S36) However, one comment was sarcastic: "On the section on the Taiwanese journalist visiting the leprosy village at Liangshan, supporting the construction of a school there for several years, my comment is that the authors want to express a close relationship between the Mainland and Taiwan. What an irony! Is our country short of money? Is our country short of civil servants?" (台湾女记者到凉山麻风村几年如一日支教建校那段，我看作者是想表达浓厚的两岸关系，真是莫大的讽刺！我国差钱吗？差公务员吗？) This stand-alone comment at least shows that there was an individual who could read and be openly sarcastic about the political overture behind the script of this event.  Figure S37. Daily count of Weibo posts that contained the keyword for "typhus" (斑疹伤寒) in 2012 among Sina Weibo users with 1000 followers or more.

Typhus
Content analysis was performed for all Weibo posts in 2012 in our database that mentioned the keyword for "typhus". There were a total of 14 posts in the whole of 2012. One post was about the death of a footballer. According to that post, he died of typhus. There are two other posts that mentioned typhus but did not fall into our five categories.  Figure S38. Daily count of Weibo posts that mentioned the keyword for "leishmaniasis"(黑热病) in 2012 among Sina Weibo users with 1000 followers or more.

Leishmaniasis
As the total number of Weibo posts was very small, content analysis was performed for Weibo posts of the whole year of 2012.       Of the 242 posts about news of diarrheal cases, 196 about two diarrheal cases after consuming ham sausages produced by a famous Chinese meat processing company. Another 24 were about a diarrheal case after drinking milk. Another 14 posts were about a funny video about a diarrheal case in a swimming pool. Another 7 posts were about a diarrheal case after consuming mixed ingredient porridge produced by a famous Chinese company. Finally there was one post about a case of a baby having diarrhea due to consuming milk that was not infant formula.
There had been many Weibo posts providing health information about diarrhea, from how to avoid diarrhea but abstaining certain food to how to manage infant's diarrhea. However, we categorized many of these posts as alternative health information/Traditional Chinese Medicine (n=163), as the information contained therein (or at least part of that) might not fit well with a modern medical understanding of diarrhea and its prevention. Many of those posts were related to food, e.g. what to eat and what not to eat in the summer. The very existence of these postscreated or re-posted by Weibo users with 1000 or more followersindicated that people were interested in how to stay healthy by choosing the right type of food to consume. "Attention! Food that is incompatible with each other should not be eaten together!" 1. Coffee + Cigarette: These make one prone to pancreatic cancer. 2. Pears + Boiled water: Eating pears and drinking boiled water, would lead to diarrhea. 3. Onions + Honey: Consumption of both will hurt the eyes, causing eye irritation. In severe cases, this will lead to blindness. 4. Tomato + sweat potato: Consumption of both together will easily lead to gall stone, vomiting, stomach ache and diarrhea. 5. Tofu + honey. Consumption of both will lead to dumbness. For the health of yourself and your family, preserve this post. Otherwise, it will lead to dysentery. Solution: To take black beans and Chinese liquorice water. 6. Consumption of shrimps with pork and chicken. This will lead to liver and kidney failure. 7. Consumption of river shrimps with tomatoes, one will be prone to food poisoning. "Fruit consumption taboos in the summer" 1. Apples. People with coronary heart disease, myocardial infarction, kidney disease and diabetes should not eat many apples. 2. Melons: Do not frequently eat a large quantity. This will cause damage to the stomach, causing to indigestion, stomach ache and diarrhea. 3. Peaches: People with poor digestive functions, the elderly and children should not eat many peaches, as peaches may damage the stomach and cause chest tightness. 4. Lychee: People with a "hot quality" (xing re), a weak yin and a "flaming fire" (yin xu huo wang), a red tongue coating, and with "internal heat" (nei re) should not eat many lychees, as one will be prone to bad reactions, such as, nausea and diarrhea, drowsiness, and limb weakness. "People with low blood pressure should not drink chrysanthemum tea with more than three chrysanthemum flowers." Chrysanthemum is effective to lower blood pressure. Elderly people whose blood pressure is relatively low or normal, are not suitable to drink chrysanthemum tea every day. They can drink chrysanthemum every few days. Each day, one should not consume more than three chrysanthemum flowers. People whose bodily constitution is relatively "cold" should add some Lycium to chrysanthemum tea. People whose spleen and stomach are weak and "cold" should only drink an appropriate volume of chrysanthemum tea in summer when the heat is intense. If one's body is weak, or whose spleen is weak, or who has stomach 2(0.44%) Original Weibo post Alternative health information illness, or who is prone to diarrhea, one should avoid chrysanthemum tea.
Other posts on alternative health information Those things that parents instructed us when we were young: Do not use fingers to point to the moon, otherwise the ears will be damaged and will fall off. Do not use chopsticks to point at other kids when one is eating congees, otherwise the kids will have diarrhea. One must spit away the seeds when one is consuming fruits, otherwise different types of fruits will grow out of your body. Do not step on one's shadows, otherwise one would not grow tall. You are picked up somewhere by your mum. If one plays with fire, one will wet one's bed. Strawberry-favored Smecta is not a drink but medicine to treat diarrhea. "At Yongzhou, a thousand children were suddenly infected with hand-foot-and-mouth disease. The only designated hospital is full." Ms. Guo from Hunan told us that her child is infected with hand-foot-andmouth disease. However, there is only one hospital that is designated to treat hand-foot-and-mouth disease and it has been full already. There is a long queue to write for registration and treatment, let alone to be taken as in-patients. # Prevent hand-foot-and-mouth disease # Just went to kindergarten to pick up my son. The teacher told me an astonishing news. Of the 11 kids that remain in our class, one suddenly had a lot of red spots appearing in his/her palm at noon. In the afternoon, the kid was confirmed to have hand-foot-and-mouth disease when s/he was taken to the hospital. When we return home, I leave everything aside. The first thing is to thoroughly clean my hands. Next, I drink a glass of water. I fume my home with white vinegar. And then I gave my son a bath, followed by a cup of Sunkist Lemon Orange Juice to supplement a large quantity of Vitamin C. Tomorrow, I will have all clothes and duvet covers disinfected.