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武漢新型冠狀病毒疫情系列之三

2020/2/14 — 17:35

香港政府的家居隔離措施廣受質疑,家居隔離的潛在患者對其同住的家人帶來相當大的問題,甭用談被要求家居隔離的人們偷走。有WhatsApp 群組留言,「有幾個大陸人剛回多倫多,即去御膳房吃飯,有伙記問他們為什麼不在家隔離十四天才出來,他們説食完這餐才隔離,令在場的伙記都好驚。」

New England Journal of Medicine在1月28日發表文章記錄一個家庭傳染的個案。案主是一個長期病患的65歲男長者,他們一家生活在越南。他和他的妻子曾於1月13日去過武漢,他在四天後發病,他的妻子沒有被感染,但他的27歲兒子在他們回越南後與其父母同住了3天後發病 (註1)。

德國也有同類例子,一位德國公司的生意伙伴在1月19日至22日從上海飛到德國,在26日確診染上武漢病毒。她在德國將病毒傳給了2位健康的德國生意伙伴,他們在1月24日開始出現病癥,公司的另2位員工沒有接觸過來自上海的員工也被感染,他們分別在1月25日和26日發病。(註2)

廣告

袁國勇的深圳香港大學醫學院在1月10日接到一家六個家庭成員的懷疑染病家庭。他們曾經到過武漢醫院和探了五位武漢親戚,那五位武漢親戚在2月3日和4日發病,但真正病情不詳。這一家庭包括2位祖父母、女兒、女婿、10歲的男孫、7歲的女孫‧當中只有七歲的女孩子沒有受到感染。那女兒的一家四口在回港後到其外母的家同住,再傳染給外母 (註3)。他們之間的傳染期大概在3至4天。那位女兒和女婿雖然有腹瀉但其排泄物不帶病毒。

鍾南山在2月9日發表了一份文件 (註4),從31個省份中的552家醫院中抽出1099個受感染病人作出研究,其研究結果是平均病人年齡為47歲,當中42%為女性,只有1%曾與野生動物接觸;30%曾到武漢;70%曾與武漢人接觸;88%發燒;67%咳嗽,腹瀉的比例很低,平均發病期為3天。這批病人除了接受輸氧、抗生素、特敏福治療外,他們中的13.7%接受皮質類固醇的系統性治療;重症的則約44.5%被注射皮質類固醇。

廣告

報告中的一句,(The median incubation period was 3.0 days (range, 0 to 24.0 days).) 被傳媒炒大為新型武漢病毒的潛伏期可達24天。

但外國專家已有文章表示皮質類固醇對控制新型病毒無效或應減至最低 (註5, 6)。

 2月11日《刺針》(註7) 有篇文章關注在今次疫情中出現在社交媒體上的假消息和歧視性的帖子。在香港以一個例子作討論。網上廣傳一帖子呼籲大家以「深吸氣」(註8) 來證明自己的肺部沒有纖維化。筆者的退休流行病學教授表示這是無稽之談。他表示:「沒有人知道肺纖維化有多嚴重和什麼時候開始,這是人死後解剖撿查才知道的。」他建議大家不要廣傳那些沒有署名的帖子。

我的退休流行病學教授朋友也評了大紀元的暗示病毒來源於非自然的文章(註9)。他的意見為:「董的文章不是她自己的研究,是翻查國際論文的review article。寫得有條理,但結論是猜想。她們的論述是新病毒的變化怪異,有和沙士和愛滋病相同的一些疍白,但又和這兩隻病毒沒有很親密的血源關係,因此自然進化的機會不大。我的意見是儘管自然變化的機會小,但人工合成的難度更大,要準確知道從沙士和愛滋病毒抽出有效疍白插入新冠狀病毒而加強它的感染性不是隨便可以做成的,一定要經過無數次實驗,每一次都要再測試插入後是否成功,這是以人力代替natural selection 的天然進化,我相信大自然的實驗室一定比人類的實驗室更有效率,所以天然比人工更大可能。」

備註

註1

Importation and Human-to-Human Transmission of a Novel Coronavirus in Vietnam

The couple’s healthy 27-year-old son had lived in Long An, a province 40 km southwest of Ho Chi Minh City, since October 2019. He had not traveled to a region where 2019-nCoV was spreading, and he had not had any known contact with any person returning from such a region. On January 17, he met his father in Nha Trang in central Vietnam and shared a bedroom with his parents for 3 days in a hotel room that had an air conditioner. On January 20, a dry cough and fever developed in the son. He also reported having had vomiting and loose stools one time before the admission. This suggests that the incubation period for 2019-nCoV may have been 3 days or less in this case.

註2

Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany

On January 28, three additional employees at the company tested positive for 2019-nCoV (Patients 2 through 4 in Figure 1). Of these patients, only Patient 2 had contact with the index patient; the other two patients had contact only with Patient 1. In accordance with the health authorities, all the patients with confirmed 2019-nCoV infection were admitted to a Munich infectious diseases unit for clinical monitoring and isolation. So far, none of the four confirmed patients show signs of severe clinical illness.

註3

A familial cluster of pneumonia associated with the 2019 novel coronavirus indicating person-to-person transmission: a study of a family cluster

patient 6, who was aged 7 years and reported by her mother to wear a surgical mask for most of the time during the period in Wuhan, was not found to be infected by virological or radiological investigations. The blood tests and CT scan of patient 6 were normal. After they returned to Shenzhen on Jan 4, 2020, patients 3–6 stayed in the same household of patient 7 (mother of patient 4) until Jan 11, 2020. Patient 7, who did not go to Wuhan or visit Shenzhen markets in the preceding 14 days, developed back pain and generalised weakness and attended the outpatient clinic at another local hospital on Jan 8, 2020. She was given cefaclor for 3 days with no improvement. She developed fever and dry cough and attended the same outpatient clinic and was treated with intravenous cefazolin (two doses) on Jan 12, 2020. She was admitted to our hospital on Jan 15, 2020, due to persistent symptoms.

Interestingly, the two younger adults (patients 3 and 4) initially had diarrhoea, which was also reported in 10·6% (15 of 142) of our SARS patients at presentation;18 however, the subsequent faecal samples of patients 3 and 4 that were collected 9–10 days after symptom onset were negative for the virus after the diarrhoea had long subsided. Up to 30% of patients with Middle East respiratory syndrome coronavirus (MERS-CoV) also have diarrhoea.19 Subgenomic RNA indicating viral replication was seen in faecal samples of patients with MERS.20 Moreover, MERS-CoV was shown to survive in simulated fed gastrointestinal juice and the ability to infect intestinal organoid models.20 Diarrhoea and gastrointestinal involvement are well known in coronavirus infections of animals and humans.

註4

Clinical characteristics of 2019 novel coronavirus infection in China

Results: The median age was 47.0 years, and 41.90% were females. Only 1.18% of patients had a direct contact with wildlife, whereas 31.30% had been to Wuhan and 71.80% had contacted with people from Wuhan. Fever (87.9%) and cough (67.7%) were the most common symptoms. Diarrhea is uncommon. The median incubation period was 3.0 days (range, 0 to 24.0 days). On admission, ground-glass opacity was the typical radiological finding on chest computed tomography (50.00%). Significantly more severe cases were diagnosed by symptoms plus reverse-transcriptase polymerase-chain-reaction without abnormal radiological findings than non-severe cases (23.87% vs. 5.20%, P<0.001). Lymphopenia was observed in 82.1% of patients. 55 patients (5.00%) were admitted to intensive care unit and 15 (1.36%) succumbed. Severe pneumonia was independently associated with either the admission to intensive care unit, mechanical ventilation, or death in multivariate competing-risk model (sub-distribution hazards ratio, 9.80; 95% confidence in

註5

Clinical evidence does not support corticosteroid treatment for 2019-nCoV lung injury

retrospective observational study reporting on 309 adults who were critically ill with MERS,2 almost half of patients (151 [49%]) were given corticosteroids (median hydrocortisone equivalent dose [ie, methylprednisolone 1:5, dexamethasone 1:25, prednisolone 1:4] of 300 mg/day). Patients who were given corticosteroids were more likely to require mechanical ventilation, vasopressors, and renal replacement therapy. After statistical adjustment for immortal time and indication biases, the authors concluded that administration of corticosteroids was not associated with a difference in 90-day mortality (adjusted odds ratio 0·8, 95% CI 0·5–1·1; p=0·12) but was associated with delayed clearance of viral RNA from respiratory tract secretions (adjusted hazard ratio 0·4, 95% CI 0·2–0·7; p=0·0005). However, these effect estimates have a high risk of error due to the probable presence of unmeasured confounders.

In a meta-analysis of corticosteroid use in patients with SARS, only four studies provided conclusive data, all indicating harm.1 The first was a case-control study of SARS patients with (n=15) and without (n=30) SARS-related psychosis; all were given corticosteroid treatment, but those who developed psychosis were given a higher cumulative dose than those who did not (10 975 mg hydrocortisone equivalent vs 6780 mg; p=0·017).6 The second was a randomised controlled trial of 16 patients with SARS who were not critically ill; the nine patients who were given hydrocortisone (mean 4·8 days [95% CI 4·1–5·5] since fever onset) had greater viraemia in the second and third weeks after infection than those who were given 0·9% saline control.5 The remaining two studies reported diabetes and avascular necrosis as complications associated with corticosteroid treatment.7, 8

A 2019 systematic review and meta-analysis9 identified ten observational studies in influenza, with a total of 6548 patients. The investigators found increased mortality in patients who were given corticosteroids (risk ratio [RR] 1·75, 95% CI 1·3–2·4; p=0·0002). Among other outcomes, length of stay in an intensive care unit was increased (mean difference 2·1, 95% CI 1·2–3·1; p<0·0001), as was the rate of secondary bacterial or fungal infection (RR 2·0, 95% CI 1·0–3·8; p=0·04).

Corticosteroids have been investigated for respiratory syncytial virus (RSV) in clinical trials in children, with no conclusive evidence of benefit and are therefore not recommended.10 An observational study of 50 adults with RSV infection, in which 33 (66%) were given corticosteroids, suggested impaired antibody responses at 28 days in those given corticosteroids.17

註6

On the use of corticosteroids for 2019-nCoV pneumonia

No clinical data exist to indicate that net benefit is derived from corticosteroids in the treatment of respiratory infection due to RSV, influenza, SARS-CoV, or MERS-CoV. The available observational data suggest increased mortality and secondary infection rates in influenza, impaired clearance of SARS-CoV and MERS-CoV, and complications of corticosteroid therapy in survivors. If it is present, the effect of steroids on mortality in those with septic shock is small, and is unlikely to be generalisable to shock in the context of severe respiratory failure due to 2019-nCoV.

Overall, no unique reason exists to expect that patients with 2019-nCoV infection will benefit from corticosteroids, and they might be more likely to be harmed with such treatment. We conclude that corticosteroid treatment should not be used for the treatment of 2019-nCoV-induced lung injury or shock outside of a clinical trial.

註7

2019-nCoV, fake news, and racism

Furthermore, fake news has led to xenophobia towards patients and Chinese visitors. On Jan 24, 2020, misinformation that “Chinese passengers from Wuhan with fever slipped through the quarantine at Kansai International Airport” was disseminated through multiple social media channels.6 Although Kansai International Airport promptly denied the fact, discrimination against Chinese people has become widespread in Japan. #ChineseDon'tComeToJapan is trending on Twitter, and Chinese visitors have been tagged as dirty, insensitive, and even bioterrorists.7

註8

由於NCP新型冠狀病毒, 有0~24天的潛伏期, 感染病毒後,沒有任何徵兆,但肺細胞已經開始了纖維化進程,直到有一天因發燒及咳嗽去醫院檢查,此時肺部通常已經50%纖維化了,為時太晚!

專家提供一方法讓你盡早知道自己肺部的狀況:

最、最、最大深度地「吸氣」並且「屏氣」超過10秒以上, 如果可以順利完成 (沒有如咳嗽、壓抑、悶、不適等) 並且每日如往常一樣, 恭喜你!證明肺部沒有纖維化,基本表示沒有感染。

特別時期,請大家「每天」早上起床,在乾淨空氣中測試!

註9

【病毒探源】武汉新型冠状病毒的科学难题

結論

關於這個新型冠狀病毒仍存在許多科學問題。根據最近發表的科學論文,這種新型冠狀病毒具有前所未有的病毒學特徵,表明這種病毒的自然發生概率是非常罕見的。該病毒感染具有非常嚴重的臨床症狀表現,對整個人類構成了巨大的威脅。勢在必行的是,包括政府和公共衛生當局在內的世界各地的科學家、醫師和人們都必須盡一切努力調查這種可疑的病毒,以瞭解其起源並保護人類的未來。

發表意見