十五年前的沙士算完滿解決,但當中的教訓却不少,包括:失職、藥石亂投、官僚各自為政、庸官延誤、圍剿異已,凡此種種與今天無異。
基本認識
筆者已寫了一篇有關沙士的技術性文章作前設。沙士,無論以什麼方式傳染,受感染者有約有6.4天的潛伏期。在這段期間,患者沒有發燒跡象,其體內雖然開始複製病毒,但其病毒不會傳染。患者的最峰的傳染期約在第十天,但他約在第8.4天(
mean serial interval),開始進行人傳人。
淘大的沙士由代號為YY的染病者在3月14日和19日到淘大過夜觸發。YY有腹瀉,其糞便當然帶菌。沙士在糞便可存活7天。但問題是沖厠鹹水可以殺死病毒,和沖淡,依附在坑洞內的細菌只能活2天。
淘大的沙士期在3月21日開始,3月24日為高峰期,70多人入院。因而,淘大的沙士擴散等不到人傳人階段,其病毒基本上來自YY,而且,“SARS的 研 究 顯 示 , 基 本 上
1個人可以傳 給 3個人左右”。這是為什麼來自民間的流行病學專家吳錦祥醫生認為,在這短短的10天有第二個主動帶菌者。他推論為老鼠。
失職
在當時,沒有人可以證明老鼠會否受沙士感染至病,成為主動帶菌者,在其體內不斷繁殖細菌。
進行這種實驗需要很高級別,第三級生物實驗室,而香港當時已擁有這類實驗室(註一)。外國實驗室已在2004年證實了實驗室老鼠可受感染,並隨後不斷找到更多例子。但當中有一個微妙的問題,科學家一般是不會找街上的老鼠做實驗的,而且,這些老鼠太污穢,無法出口。這關鍵性實驗只能在香港進行,可是香港不做。
藥石亂投
由於沙士在早期連種菌也做不到,沒有先例,下錯藥不能過份指責。但與外國如加拿大等比較,其藥物治療(Pharmacologic
Treatment of SARS: Current Knowledge and Recommendations)後果是相當嚴重的。
Twenty-nine patients (20%) were admitted to the ICU with or
without mechanical ventilation, and 8 patients died (21-day mortality, 6.5%;
95% confidence interval [CI], 1.9%-11.8%). ----Great Toronto
ICU mortality ~25-50%----Hong Kong
由於對早期患者用皮質類固醇治療導致許多患者病病情惡化,本該不死的變為枉死(註二)。
香港運用的高劑量或脈衝類固醇應只用作挽救療法,即已出現嚴重肺炎或更後期。沙士患者有3個可識別的致病階段,其持續時間不同,可能出現重疊。 這些階段是第一期的病毒複製,第二期的炎性肺炎和第三期的殘餘肺纖維化。
長期和高劑量皮質類固醇治療不單無效還會做成併發症,包括免疫系統失調,增加受感染機會,引致肺炎,真菌感染和“骨骷症”(香港12%)。
In Hong Kong, around 12% (49 out of 418) of patients with
SARS were found to have magnetic resonance imaging proven AVN of the hips and
knees.
該指責的是醫管局在政府報告『汲取經驗,防患未然』仍然死撐。
官僚各自為政
楊永強與陳馮富珍互不通消息,楊永強與廖秀冬不和。楊永強很遲才知道沙士患者出現腹瀉。醫管局內的專業支援不足,但它又不信任中大的專家,認為他們不聽話。香港大學感染及傳染病講座教授及微生物學系系主任的袁國勇教授也不是政府團隊。
其早期數據只交給沈祖堯教授,但沈祖堯不是這方面專家。其沙士樣本延誤了一個月才送給外國專家。
總之一句話,政府高層在當時考慮政治,尤其是經濟影響,多於醫療。
庸官延誤
淘大沙士從開始至高峰(24日)只有3天。庸官們在26日才洗太平地,在31
日 才出隔離令,在4月 7 日 至10
日,與淘大花園業主立案法團搞大清潔時,其疫情已過。
當中有一小插曲,陳馮富珍在3月31 日的內部會議中質疑疫情已過,下隔離令可能有問題。在當時的有殺錯無送過的氣氛下,她當然成了過街老鼠,但從事後的數字看,隔離令似乎對其發展曲線沒有影響。
圍剿異已
政府至今仍然不提老鼠可以是主動帶菌者,提出這質疑是吳錦祥醫生,當年本在北京發展其醫療業務,受其好友呼喚,回港組織了中大和小部份港大醫療專家,希望協助香港面對沙士危機,可是一頭栽進入政治旋渦。姑勿論其立論是否正確,他像孫悟空大鬧天宮,干擾了政府的算盤。
他在立法會的專責委員會中被廖秀冬帶頭圍剿,嘲笑他分不開家鼠和渠溝老鼠;曾浩輝醫生表示忘記了有否見過他,也在自已的作證中指吳的《刺血 針》報告引錯資料(註3);艾勵新獸醫師認為吳博士的陳述書頗自以為是(註4);食環署防治蟲鼠主任主管袁銘志當他做生意的(註5)。
對市民的教訓
雖則,若沙士重現,醫療人員的處理手法已大幅改進,應付有餘,但沙士事件對市民的政治教訓至今猶新。
A few controlled clinical trials of some of these
therapeutic agents have been planned in case SARS re-emerges.
我們今天看到的沙中線、港珠澳大橋、豆腐渣工程等,其問題出現可能是很久以後的事。例如意大利塌橋,沒有人相信可以發生在第8
大經濟體系,其國內民間一直有聲音關注其安全問題,指責其缺乏保養。
現今的港人比15年前更不信任政府。我們更加需要這些吹哨人whistleblower。可是,對一般市民,容易被政府的宣傳洗腦。在歪理充道的香港,沒有人會理會細節。
最重要的教訓是:當事情涉及重大公眾利益,政府永遠不會說出事實及事實的全部,無論它是否民生(註6),它的最終永遠是政治。
--------------------完-------------------
備註
註一
: Risk Group 3
(high individual risk, low community risk)
A pathogen that usually causes serious human or animal disease
but does not ordinarily spread from one infected individual to another,
directly or indirectly. Effective treatment and preventative measures are
available.
e.g.
SARS (8096 cases and 774 deaths 2002-3)
: So it is done in Bio Safety Lab Level 3
: Although Hong Kong only has laboratories with a maximum
biosafety level of three,----2018 SCMP
: Biosafety Level 3 Laboratory - LI Ka Shing Institute of
Health Sciences
: Since 1997, several biosafety level 3 laboratories have
opened at two of the city’s universities, while two government
departments now have the capacity to do both laboratory and animal experiments.
These too are part of the new labs network. “With this extra capacity has come
more work; the capacity we have is heavily used,” Peiris says.
: 2002 - 2004, Department of Microbiology, University of
Hong Kong
"Hong Kong University Research Centre for Emerging
Infectious Diseases (HKURCEID)"
Assisted engineers and architects in the planning and
oversight of construction of Biosafety Level 3 and 4 facilities for studies of
high virulence influenza (particularly isolates from birds and pigs arising in
China) and high risk diseases (including SARS) which included both laboratories
and animal facilities (now commissioned as the Hong Kong University Research
Centre for Emerging Infectious Diseases (HKURCEID)).
: 2005, Queen Mary Hospital, University of Hong Kong
"Consultant to Tysan Project Management for the design
and construction of a BSL-3 laboratory in the Pathology Department, Queen Mary
Hospital, University of Hong Kong"
: Similarly in 2003, when a scientist in Singapore became
infected with SARS while researching West Nile virus, the authorities asked WHO
to help investigate the case. A team of 11 experts from Singapore, WHO’s
Regional Office for the Western Pacific and CDC concluded that the
contamination had been caused by lax biosafety practices, and recommended
measures including national legislation for biosafety standards and a tracking
system for transportation of infectious agents within Singapore and abroad.
註二
處理手法比較
Twenty-nine patients (20%) were admitted to the ICU with or
without mechanical ventilation, and 8 patients died (21-day mortality, 6.5%;
95% confidence interval [CI], 1.9%-11.8%). ----Great Toronto
ICU mortality ~25-50%----Hong Kong
Antiviral therapy
Ribavirin was the most commonly used empirical antiviral
agent for SARS. It is a broad-spectrum purine nucleoside analogue which
inhibits both RNA and DNA viruses by interfering with nucleic acid synthesis.
There is experimental evidence to show that it has immunomodulatory effects in
the treatment of mouse coronavirus hepatitis 24. Subsequently, it was found
that ribavirin has no direct in vitro activity against SARS-CoV 25. Higher
doses given intravenously resulted in more frequent and severe adverse effects
including haemolytic anaemia, elevated transaminase levels and bradycardia 13.
隨後,發現利巴韋林對SARS-CoV 25沒有直接的體外活性。靜脈內給予更高劑量導致更頻繁和嚴重的副作用,包括溶血性貧血,轉氨酶水平升高和心動過緩。
The management of coronavirus infections with particular
reference to SARS
Samson S. Y. Wong
Kwok-Yung Yuen
Journal of Antimicrobial Chemotherapy, Volume 62, Issue 3, 1
September 2008, Pages 437–441, https://doi.org/10.1093/jac/dkn243
Published: 18 June 2008
SARS-CoV is not unduly resistant to chemical disinfectants
(such as alcohols, sodium hypochlorite and povidone–iodine) and heat (such as
56°C for 60 min or 60°C for 30 min), but can survive in faecal and respiratory
specimens for over 7 days at room temperature.
SARS的藥物治療
Ann Acad Med Singapore 2007;36:438-43
However, many patients worsened clinically despite receiving
corticosteroid treatment, and higher doses or pulse steroid were required as
rescue therapy. Three steroid regimens were commonly used
然而,皮質類固醇治療導致許多患者病病情惡化。高劑量或脈衝類固醇應只用作挽救療法。類固醇方案通常有三種方案。
Corticosteroids could potentially increase or prolong viral
replication and worsen disease. Prolonged and high-dose corticosteroid therapy
is associated with a number of complications including immunosuppression and
opportunistic infections, particularly ventilator-associated pneumonia and even
invasive fungal infections, and avascular necrosis (AVN)
皮質類固醇可能會增加或延長病毒複製並使疾病惡化。 長期和高劑量皮質類固醇治療與許多並發症有關,包括免疫抑制和機會性感染,特別是呼吸機相關性肺炎甚至侵襲性真菌感染和缺血性壞死(AVN)
In Hong Kong, around 12% (49 out of 418) of patients with
SARS were found to have magnetic resonance imaging proven AVN of the hips and
knees.
Avascular necrosis (AVN), also called osteonecrosis or bone
infarction, is death of bone tissue due to interruption of the blood supply
缺血性壞死(AVN),也稱為骨壞死或骨梗塞,是由於血液供應中斷導致的骨組織死亡
Steroids should not be used in the early phase of SARS, but
rather as rescue therapy, as it may impair host viral clearance.
類固醇不應該用於SARS的早期階段,而應該用作挽救療法,因為它可能會損害宿主病毒清除率。
There are 3 identifiable pathogenic stages of SARS of
varying duration, which may overlap chronologically. These stages are viral
replication, inflammatory pneumonitis and residual pulmonary fibrosis.
Antiviral therapy may be considered during the viral
replication phase. Immunomodulation therapy such as corticosteroids should be
withheld until the second week to counteract the BOOP like phase, and pulse MP
for patients with clinical deterioration manifested by persistent fever,
worsening radiographic opacities, and hypoxaemic respiratory failure.
SARS有3個可識別的致病階段,持續時間不同,可能按時間順序重疊。 這些階段是病毒複製,炎性肺炎和殘餘肺纖維化。
在病毒複製階段可以考慮抗病毒治療。 免疫調節治療如皮質類固醇應停止至第二週,以抵消BOOP(閉塞性細支氣管炎)樣期,並且對於臨床惡化的患者脈搏MP表現為持續發熱,惡化的放射照相混濁和低氧血症性呼吸衰竭。
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3676866/
Antiviral therapy for URI was defined as treatment with
rimantadine, amantadine, oseltamivir or zanamivir that was prescribed to treat
influenza URI. M-2 inhibitors were considered only if used to treat influenza A
infection. The timing of initiation of antiviral refers to the delay between
the first positive influenza test and the first day of treatment. Time from
onset of symptoms to treatment was not assessed because it could not be
reliably done due to the retrospective nature of the study.
URI的抗病毒治療定義為用於治療流感URI的金剛乙胺,金剛烷胺,奧司他韋或扎那米韋治療。 僅在用於治療甲型流感感染時才考慮使用M-2抑製劑。
啟動抗病毒的時間是指第一次陽性流感測試和第一天治療之間的延遲。
從症狀發作到治療的時間沒有評估,因為由於研究的回顧性而無法可靠地完成。
註三
最後,我想說一點,我也拜讀過Dr NG在Lancet,即《刺血 針》內的報告。我自己發覺他有一些資料可能不大準確,因為他有4個reference,都是引述一些報紙的。我曾核對有關資料,發現其實不大準確。譬如其中一個是reference
14,指 在 廚房的地上和廚房 的“sink盆”找到病毒,其實這並不正確。所以,可能由於資料上有所偏差,使研究結果出了問題。
註四
8.58 艾勵新獸醫師又向專責委員會表示,雖然吳錦祥博士或曾就這種新冠狀病毒可能引起的病理變化提出假設,但對於吳博士在其 陳 述 書 中 指 “我 向 艾 勵 新 獸 醫 師 描 述 可 能 出現的病理 變化”,他認為吳博士的陳述書頗自以為是。
註五
梁劉柔芬議員: ……或者甚至乎那一類。但是,你在最初那10多分鐘,你的概念之中,或者是其他人在介紹的過程之中……概念之中,令你覺得吳博士為甚麼會在場……參與那個會議呢?
袁銘志先生:我不知道他是甚麼背景、甚麼身份,因為我不認識他。我最初以為他是做生意的,因為我不認識他,那個房間內有兩個人是我不認識的,即羅醫生和StephenNG。我有少許奇怪,就是為甚麼一個好像做生意的人會參與,提供意見呢?因為我記得局長好像問過他去北京,他說甚麼賣儀器的……我不是很記得了。
梁劉柔芬議員: OK。
袁銘志先生:所以我是有少許奇怪,為甚麼他會在那裏提供意見,一個做生意的。
註六
Initial Shock to China and Hong Kong
We first calculate the shocks to the economies of mainland
China and Hong Kong (SAR), which were hit most heavily by the disease, and then
work out some indexes summarizing how these shocks are likely to occur in other
economies. There are three main shocks, based on observations of financial
market analysts about the existing data emerging from China and Hong Kong:5
- A 200 basis-point increase in country risk premium.6
- A sector-specific demand shock to the retail sales
sector, amounting to a 15 percent drop in demand for the exposed
industries in the service sector.
- An increase in costs in the exposed activities in
the service sector of 5 percent.
These shocks are then scaled to last only 6 months rather
than 1 year.