- What is an asymptomatic carrier?
An asymptomatic carrier is a person who is infected with SARS-CoV-2 (tests positive for it), which is the virus that causes Covid-19, but displays no clinical symptoms. There are two possibilities: 1. Some people never develop any symptoms throughout the course of the infection, and the body just clears the virus on its own. 2. Some people develop symptoms later — the pre-symptomatic phase is called the incubation period, which is usually between 2 and 14 days.
Here we are talking about the first category: those who never develop symptoms.
- Can asymptomatic carriers of SARS-CoV-2 pass it on to other people?
- How many asymptomatic cases out there?
We don’t know. But here is a summary of some of the existing evidence.
- A study based on screening results of 565 Japanese citizens evacuated from Wuhan estimates the ratio at 30.8%.
- A study on the Diamond Prince cruise (not peer-reviewed) estimates the ratio at 17.9%.
(Note that when the screening is aggressive, the number of true asymptomatic carriers can be overestimated, because some people might test positive when they are in the incubation period. The share of asymptomatic cases on Diamond Prince was around 50% at some point, but some developed symptoms later.)
- In South Korea, where over 300k tests have been performed, over 20% didn’t show symptoms during hospitalization.
- According to SCMP, “classified Chinese governmental data” shows about 1/3 of all detected cases in China are asymptomatic.
- Chinese health authorities did not disclose the number of known asymptomatic cases to the public prior to 31 March. Since 31 March, the National Health Commission (NHC) began to disclose the daily active number, but not the cumulative number. However, one province — Liaoning Province reported the cumulative number on 3 April. According to Liaoning Health Commission, the province has 141 cumulative confirmed cases (excluding asymptomatic ones) and 56 cumulative asymptomatic cases as of 2 April. Although a very small sample, the ratio then is 28.4%.
- In Iceland, as of 18 March, 218 positive cases were identified and “about half of those who tested positive were non-symptomatic”. But we don’t know how many of these are pre-symptomatic.
- On 30 March, the director of the US CDC warned that “as many as 25 percent of people infected with the new coronavirus may not show symptoms”.
Taken together, most existing evidence seems to suggest between 20–30%.
- How are asymptomatic cases discovered?
In South Korea and Iceland, mass testing.
In China, the NHC says there are four main ways: 1. monitoring of close contacts; 2. investigation of clusters; 3. investigation of source of infection; 4. screening of population groups who have been to high-risk areas.
More recently, a few publicly reported cases were discovered through “get back to work” screenings (employers ask employees to test for coronavirus or offer free tests before they can get back to work). In Henan Province, three doctors tested positive without displaying symptoms in the screening organized by the hospital they work at in order to resume normal healthcare services. A resident in Wuhan tested positive without symptoms on 17 March after his employer required all employees who had infected family members to provide testing proofs. This resident’s father was diagnosed in January. He was not tested back then because of shortage of testing kits in January.
- What is China’s policy on reporting asymptomatic cases?
The NHC confirmed that asymptomatic carriers can be infectious in its “Covid-19 Diagnosis and Treatment Plan” (5th Edition), published on 4 February.
On 5 February, the NHC instructed that asymptomatic cases should be included in confirmed cases.
However, since 7 February, with the publication of the “Covid-19 Prevention and Control Plan” (4th Edition), asymptomatic cases have been excluded from the count of confirmed cases. They become counted as “confirmed cases” if symptoms are developed. The numbers are still reported to healthy authorities, but not disclosed to the public.
Since 31 March, the NHC has been disclosing the daily active number, but not the cumulative number.
- What is China’s policy on the management of asymptomatic cases?
According to the “Prevention and Control Plan”, once detected, asymptomatic cases should be reported to the CDC system within 2 hours. Local health authorities should complete the epidemiological investigation for each individual case within 24 hours. Asymptomatic carriers should be put in centralized quarantine and monitored for 14 days. In principle, the quarantine can end after 14 days and if the person tests negative twice. But the quarantine period should be extended if they still test positive. The close contacts of asymptomatic carriers should also be quarantined for 14 days.
The Wuhan resident mentioned earlier shared his own experience as an asymptomatic carrier. He was sent to Jinyintan Hospital – the specialist infectious diseases hospital that has treated the most severe cases during the outbreak – and hospitalized for some 7-8 days even without displaying any clinical symptoms. He was given antiviral medication. After discharged from hospital, he was quarantined in a hotel. His mother was also quarantined in a hotel for 14 days and tested several times (negative).
Wear a mask.
All makeshift hospitals in Wuhan have closed as of today (10 March 2020).
The darkest hour is finally gone.
But it’s not time to celebrate, but to remember. Remember the lives lost and millions of hearts broken.
Remember the woman playing the gong on the balcony crying for help because her mom was dying and nowhere to be treated.
Remember the disabled boy who starved to death at home because his father was taken to quarantine.
Remember the person who killed himself because no hospital bed for him and he dared not return home for fear of passing it on to his family.
Remember the migrant workers who helped build this city and have been forced to sleep rough since the lockdown.
The migrant care workers who had no home to return after they got infected while caring for patients, and no shequ (community) to apply for hospitalization for them because they don’t have Wuhan hukou.
And the migrant workers who helped build a hospital miraculously in 10 days only to face discriminations and dreadful quarantine conditions when returned home.
Remember the woman medical workers who shaved their head and then their body was used by state media as a propaganda tool.
Remember the person who donated all the masks that were substitute for his unpaid salary.
Remember the director whose entire family of 4 were killed by the virus.
Remember the family of 5 – a young couple and their 3 children – who travelled from Hubei to Quanzhou and were all killed by the collapsing of the quarantine hotel they were placed in.
Remember the pregnant woman from rural Hubei who gave up treatment after her family had borrowed and spent 200k CNY on health care and they couldn’t afford it anymore. The doctor said her conditions were improving. The next day after she died, authorities announced free treatment for all covid-19 patients.
Remember the grandpa who learned to use weibo to seek for help after his daughter had already died from covid-19 and both granddaughter and himself were infected. He died a month after he sent that first “nihao” post.
Remember the 29-year-old doctor who died of covid-19, leaving behind her 2-year-old son and her husband and first love. They had met in medical school and planned to “grow old together”.
Remember the doctor who wrote “I can” & “I understand” on that “letter of reprimend”.
We’ll never know the full extent of it. But for the tip of iceberg we know: Never forget. Never forgive.
Crowd-sourced online archives:
I doubt if I’ll have time for any ‘serious’ blogging here but for now I might use this place for organizing and recollecting some of my tweets – or, fragments of thought in the time of fragmentation. Today’s theme is politics and the Chinese language, including political “newspeak”, internet slang terms, and some other stuff.
If interested I also wrote something about how censorship has corrupted the Chinese language on my 中文博客.
My favourite example of 'political' translation is this. The dictatorship of the proletariat is trans. as 无产阶级专政. "… twitter.com/i/web/status/1…—
Chenchen ZH (@chenchenzh) March 21, 2019
I guess it’s because Chinese translators of Marxist works didn’t like the negative sounding of 独裁. So, in the political lexicon of the modern Chinese language, when it’s “bad” dictatorship it’s 独裁. When it’s “good” dictatorship it’s 专政.
— Chenchen ZH (@chenchenzh) March 21, 2019
Reminded of some Chinese #newspeak. So we grew up learning that there’re 差额选举 (literally different-number election) and 等额选举 (equal-number election). The former means more candidates than seats and the latter same no. Choosing two apples from two apples… is not 选举. https://t.co/lFLvQPO0r0
— Chenchen ZH (@chenchenzh) April 11, 2019
— Chenchen ZH (@chenchenzh) April 11, 2019
Chinese acronym for a decorative section of #lianghui representatives: 无知少女. 无 – 无党派人士 non-partisans, 知 – 知识分子 intellectuals, 少 – 少数民族 ethnic minorities, 女 – women. Together the acronym 无知少女 means ignorant girl. #TwoSessions2019 #learnchinese
— Chenchen ZH (@chenchenzh) March 6, 2019
— Chenchen ZH (@chenchenzh) November 10, 2018
So…Chinese words for non-democratic govt.
Autocracy; despotism 专制
Dictatorship 独裁 (专政 when it’s people’s democratic dictatorship)
Totalitarianism 极权主义/极权政体 (many people mistakenly write 集权)
— Chenchen ZH (@chenchenzh) March 21, 2019
Internet slang terms for the right. Usually pejorative.
皇汉 – Han ultranationalists. Han supremacists
穆黑 – Islamophobes
田园右 – usage varies. Could be associated with any of the following stances: strong state; economic liberalism; social Darwinism; cultural conservativism
— Chenchen ZH (@chenchenzh) January 24, 2019
Internet slang terms of Chinese sinophobes.
支人/支豚 Chinese people
支性 Chineseness, Chinese inferiority.
脱支 Emigration from China
— Chenchen ZH (@chenchenzh) February 3, 2019
Emigration is physical 脱支 and "becoming civilised" is spiritual 脱支. Both nationalists and "reverse nationalists" su… twitter.com/i/web/status/1…—
Chenchen ZH (@chenchenzh) February 04, 2019
Essentialist narratives of Chinese inferiority are quite popular in the Chinese twitter community and indeed have a… twitter.com/i/web/status/1…—
Chenchen ZH (@chenchenzh) February 03, 2019