2020年1月31日星期五

Wuhan pneumonia in context – why we need not overreact 20200131

There seems a universal (well at least in HK) panic about the Wuhan pneumonia outbreak, with at least 95% of the people we see in the streets wearing masks – a spectacle – and many organisations completely shutting down (including the govt) for fear of contagion…

This is despite to date only 10 people in HK have been confirmed cases. The status at the time of writing looks like this:

Figure 1: current outbreak statistics












If you look at the numbers, however, the situation is perhaps much less frightening than the media (and officials) have whipped up:

1) Death rate similar/weaker than normal flu? As table below shows, the death rate of diagnosed cases in the epicentre, Wuhan, may be high at 5.7%, but by the time you look at the province at large, it drops to 3.5%, and overall China-wide, the ratio becomes a low 2.2%. HK’s death rate is a lucky big Zero:

Table 1: WARS statistics











Compared to other headline flu pandemics reported (see FR1 below), where death rate range around 0.03-0.08% of population, the current rate of death, even in Wuhan, is a tiny fraction (see right column in Table 1, at 0.0012%) – ie there needs a 100-300x increase in deaths from current Hubei levels (0.00027%) to match past pandemics alone – ie. 16k – 49k in casualties in total. Luckily, the Hubei death toll is a low 162 as of today; 

2) The death rate have been dropping – usually the early deaths tend to be more heavily reported/collected as a statistic compared to the actual infected population, while the catching up by the latter leads to a more normalised, actual rate in time (red line below). Public awareness may also put a stop to accelerated growth in death rates, which the blue line below could well be suggesting, falling from 3% to early 2% in the past few days. A consistent departure from the red trajectory will mean we can largely return to normal activities:

Chart 1: death rate tends towards the disease’s true virility in time














3)      Vigilance is ultra-high this time – compared to SARS (when prevention only scaled up after several weeks of casualties), people are armed to the teeth within days, thanks to the magnifying effect of social media and international measures (which are unprecedented – chartered flights to retrieve nationals from China, for example). As a result, the spreading of the disease will likely be much less rapid. Here is a map showing which country to be in with any epidemic outbreak. Not surprisingly, OECD countries come top:

Figure 2: which countries are best prepared for an outbreak?
























4)      Possible longer drag than SARS – One feature that does not talked about is the timing of the current outbreak – instead of a March incident like in SARS, we are in January, that means the period of time before it becomes too warm for virus to spread diseases will be longer than during the SARS episode, which ended in June 2003 as temperature rose.

This time round, the outbreak will potentially be lengthened by two months. Hopefully the growth in case numbers (red line in Chart 2 below) will see a tailing off much faster this time compared to SARS (blue line) on increased vigilance.

Chart 2: Case growth rate may decay like the SARS outbreak












5)      Virility tracking will give the answer – the viciousness of the current outbreak has yet to be proven, but if the trends discussed thus far hold, the situation stands good chance stabilising at current levels.

In the next few weeks we should have our answer, but if anyone even remembers the not too distant 2009 avian flu outbreak, which is so far 1000x higher than WARS in death rates (red dotted line, Chart 3), people seem much more ready, if not more than necessarily prepared this time round.

Chart 3: log chart comparing current death rates to past pandemics


















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Reference – further reading 1 (FR1)

Flu causes more death than you may think!

Every flu season, a lot of people die from this disease, mainly from complications such as pneumonia

More than 200,000 people are hospitalized each year in the United States for the flu illness and its complications and between 3,000 and 49,000 people die each year from the flu. The number of flu deaths every year varies. That is 1.5%-25% of hospitalised flu victims die each year!

According to the World Health Organization (WHO), about 3 to 5 million cases of severe flu illness and about 250 000 to 500 000 flu season deaths worldwide occur due to the influenza virus. That is anywhere between 5% to 17% of deaths.

Really big pandemics in context

The world has seen five pandemics during the last century, which took a large number of lives. Here are the figures of deaths that occurred in the United States and Worldwide during those years.

1. 1889 Russian Flu Pandemic – about 1 million flu deaths (0.07% global population)

2. “Spanish flu” A of 1918-19 caused the highest number of influenza-related deaths: approximately 500,000 deaths occurred in the U.S. and 20 million worldwide. That figure is more than the total number of deaths caused by the World War one — 16 million. As a matter of fact, during that year, the flu had killed more people than any other illness in recorded history. (1.1% global population)

3. “Asian flu” A of 1957-58 caused 70,000 deaths in the United States and about one million to two million deaths worldwide (0.07% global population)

4. “Hong-Kong flu” A of 1968-69 resulted in 34,000 deaths in the United States and an estimated one million to three million people died worldwide. (0.08% global population)

5. 2009 H1N1 Flu Pandemic – about 18,300 deaths in the United States and up to 203,000 deaths worldwide (0.003% global population)

So amongst the most feared pandemics in history, only the Spanish flu was of truly frightful scale when 1.1% of population perished.


Reference – further reading 2 (FR2)
Trends in Recorded Influenza Mortality: United States, 1900–2004, by Peter Doshi

In results section author concluded: “An overall and substantial decline in influenza-classed mortality was observed during the 20th century, from an average seasonal rate of 10.2 deaths per 100 000 population in the 1940s to 0.56 per 100 000 by the 1990s. The 1918–1919 pandemic stands out as an exceptional outlier.”

2020年1月29日星期三

權貴樹碑連連 社區白象處處

載於2020年1月29日信報, 完整版如下:

區議會選舉剛在去年11月完成,一洗過去建制派盤踞的格局;隨之引來的熱議,莫過於前任議員多年來到底為選民及當地社區有何建樹。其中一個最惹人詬病之處,乃是各區區議員是否於過往數年以樹碑立傳、揚名立萬為目的,不建立真正便民設施,卻大量建造各樣光怪陸離且毫不中用的形象地標【表1】。

表一:較「著名」形象工程一覽
地區
民間謔稱
造價(萬)
竣工日期
網民評價
灣仔
金龍像
300
2003
一身俗氣金色外皮
旺角
金魚像
34
2011
難令人聯想旺角金魚市集盛況
筲箕灣
東區文化廣場
9000
2019
佔地頗大,卻欠缺基本設施
鰂魚涌
不能避雨亭
21
20155
無助市民避雨兼佔用路面空間
四不像燒鵝
120
2013年,已拆
造型似鵝非鵝,無實際作用
觀塘
海濱音樂噴泉
5000
未知
噴泉阻礙遊人於草坪上休憩
葵芳
安全島
85
20184月,已拆
貌似墳墓,設計混亂如同「建築廢料」
屯門
石躉
20
20198月,已拆
既似龜殼,也似「古墓」、「山墳」,用途不明

究其原委,不難發現,自2008年起,全港十八區區議會每年都總共獲得由政府撥出的三億元,作為地區小型工程的預算;到2013年,時任特首梁振英更將預算大幅提升至每區一億元!在缺乏本地諮詢,兼且專業規劃知識欠奉的生態下,最終撥款淪為當屆區議員鞏固形象的本錢,卻對當地民生或區域形象毫無正面作用。

筆者隨手拿來兩個人流旺盛,地點居中的例子:旺角金魚像【圖一】和灣仔「蟠龍匯瑞」金龍像【圖二】。這兩頭小白象不但霸佔市區黃金地段,且耗費龐大;對市民不但毫無實際用途,更難對心靈有任何鼓舞或激勵作用!

圖一:旺角金魚像早於筆者攝影之前,已被有心人狠批

圖二:灣仔金龍像霸氣十足,拒人千里

以上白象工程,用料只是普通的水泥和顏料,為何工程費用會動輒過百萬?灣仔那條名為蟠龍匯
瑞」的「彫塑」竟耗資300萬元!相比之下,置於交易廣場、出自雕塑大師朱銘手下的太極人作品【圖三】,不但引人入勝,洗滌心靈,就算是其兩米長同系銅雕作品在2009年拍賣也只達500餘萬元,試問閣下在有選擇情況下,會選霸氣金龍,還是優雅太極?

再仔細一看白象下題字,滿目所見盡是官官互賀、自得其喜的痞態【圖四】,哪有為民造福,改善社區的半點意思?

圖三: 朱銘 太極系列雕塑一例
圖四:究竟建造金魚像是為了突顯該區特點,還是純粹方便碑上的社會權貴刷政績?

貪便圖利,綠蔭無緣!

隨著城市發展,石屎森林不斷增高加濶,市民與自然日漸疏離,不但對身體無益,亦令人精神受壓。然而就算在較具規模的公共空間,樹木都逐漸被清洗淘汰,這若不是官僚為求方便,對綠化敷衍塞責,實在想不出其他原因!

以旺角金魚工程所在為例,只要在空地種植數棵成熟樹木,就已經可以將視之生惡的水泥佈景【圖五a】變成翠碧綠洲【圖五b】。就算兩層樓高的成熟大樹,成本亦只需5至10萬一棵,故此,全面覆蓋水渠街休憩空間若一萬方呎,相信也只要十數棵,總成本200萬以下已可埋單。
圖五a:水渠街和金魚像現狀 — 光禿一片,枯燥乏味
圖五b:水渠街和金魚像 — 綠化後一片生氣,綠影婆娑

再看灣仔,空地面積較小,約5千呎而已,同樣以兩層樓高的成熟大樹為例,6至7棵已可成事,總成本亦可減半:100萬的經濟效益,必定比金龍像長遠兼受歡迎!【圖六a及六b】
圖六a:金龍像現狀 — 日曬雨淋,身震耳聾

圖六b: 金龍像綠化後鳥語花香,蟲鳴蝶舞?


重新植樹鬧市 再度還民自然

以上由樹林取代大白象之倡議,其實順理成章,自然不過,奈何長處冷氣間之官僚,及以福利掛帥,置民生不顧之前任區議會,卻從未有此思維。以至經年累月之下,形象工程遍地開花,嘍嘍蟻民卻只見自己鄰里左右之綠化空間買少見少!由科學角度解釋,除了樹蔭能於炎炎夏日供市民避暑乘涼,更能大大減輕城市熱島效應,其效果之大,連筆者也大出意外——炎熱天時,樹蔭下地面溫度不但較氣溫低數度,相對日漸泛濫的石屎/瀝青地面更相差以倍數計,見【圖七】。

圖七:城市樹蔭能降低地面溫度達36度之巨!
這般既經濟又惠民的政策,政府不但遲遲洞察不到,反而不斷建造動輒數以百萬元計、華而不實的廢物。當今行政結構設計錯誤(過度中央集權)應是此現象之罪魁禍首。

外行管內行 內行不在旁
除了上述之行政權力集中的結構問題之外,樹木管理工作的分工更是雜亂無章,人力分配與工作需求嚴重錯配!舉例說:政府各部門總共有137位註冊樹藝師,理論上「照顧」全港約170萬棵已知管轄範圍內的樹木。

然而,各部門的樹藝師人數懸殊,旗下最多樹木的路政署中,八位樹藝師要為遍佈全港的60多萬樹木負責,每位平均處理近8萬棵樹,即在一年365日無休的情況下,都要每天擔當214棵之眾;反過來,最「悠遊」的房屋署各專家,只須每日看守18棵而已,即是兩者工作量相差12倍!

表二:全港樹目管轄情況一覽
部門
護養樹木數目(萬棵)
樹藝師(名)
每名樹藝師需管理的樹木數目(棵)
漁農自然護理署
3.80
28
1,357
渠務署
2.48
1
24,800
路政署
63.30
8
79,125
房屋署
10.08
15
6,720
康樂及文化事務署
51.50
70
7,357
水務署
15.71
0
-
地政總署
難以點算*
13
-
建築署
20.00
1
200,000
整體
166.87
136
1,227
*由於地政總署管轄上述土地樹木眾多,故難以點算。
來源:2018年立法會文件

難怪旺角/灣仔這些最渴求綠化的路邊公共空間,只見樹木因營養不良、病死、或為行人安全而犧牲,卻不聞有計劃、有愛心的本區園丁去施肥淋水,更遑論爭取樹木應有的生存條件,及擴大各區綠化比例。

曾幾何時,政府似乎感覺到問題的重要性,並成立樹木辦,可惜最後無疾而終,而各樹木專才亦由本應是樹木保育的推動者身份,成為各官僚手中隨意殺樹滅林的劊子手。如要有效推動市區綠化,實應將所有樹藝師和一切樹木的種植及維護工作者全數撥歸漁農署管轄,但由區議會或其他地區單位負責綠化方針,包括財政資源的分配。只有以由下而上的方式去美化當區環境,才能充分釋放居民的積極性並制訂出靈活多樣卻又合乎居民利益的環境政策。

筆者特別鳴謝香港浸會大學傳理系學生黃兆楓協助草擬本文,及收集和整理相關數據圖表。