I’ve made my pleas for a humanitarian response to the outbreak in China but have not underscored the reasons for serious concern. Here I outline the realities we are facing, what we know, what we don’t yet know, and why we will know much more in two weeks.
- This virus cannot be modeled on past outbreaks of SARS. We know that compared to SARS this virus has vastly outstripped the increase in the number of cases by at least an order of magnitude if not more.
- The symptoms of infections of this virus are atypical of other SARS-like coronaviruses.
- There could be a 5-7 (or even up to 14, per CDC) day asymptomatic period, during which the thousands of individuals who traveled out of China would have had time to interact with and infect tens of other people, meaning tens of thousands of people would have been infected before the end of January.
- These people are now beginning to experience
- Dry Cough
- Shortness of breath
- Nasal congestion
- After a few days they will experience
- After a day or so more they may experience
- Abdominal pain
- Loose stools
- You can hear Dr. John Campbell review some individual cases in detail in this useful video:
- In the critical phase, some patients begin to recover and feel better, only then to crash and become critically ill with low oxygen levels, eosinohilic and upper and lower lung pneumonia due to cellular death in the alveoli (grape-like clusters of air sacs in the lungs).
- Today on 2/6/2020, clearly those people would have had a chance to interact with tens of people each, potentially infected hundreds of thousand of people, who will in five more days’ time.
- Around the time that these individuals begin to present symptoms, some of the first cohort will be entering the critical phase of the disease. At this time, no one can predict who will progress and who will not. Originally reports from China were that the elderly and the immunocompromised were the only persons dying. Now, it’s clear that there is not any clear age-associated risk.
- Take, for example, the case of Dr. Wenlian Li.
Dr. Li’s report in December led the nation of China to take the SARS-like coronavirus theory seriously. He was harassed by local police and made to sign a retraction. But national government agencies took his warning serious and Li returned to work to help care for patients, and became infected. Dr. Li died today; he was 33.
Details from late January in this article reviewing clinical presentation:
“Common symptoms at onset of illness were fever (40 [98%] of 41 patients), cough (31 [76%]), and myalgia or fatigue (18 [44%]); less common symptoms were sputum production (11 [28%] of 39), headache (three [8%] of 38), haemoptysis* (two [5%] of 39), and diarrhoea (one [3%] of 38). Dyspnoea* developed in 22 (55%) of 40 patients (median time from illness onset to dyspnoea 8·0 days [IQR 5·0–13·0]). 26 (63%) of 41 patients had lymphopenia. All 41 patients had pneumonia with abnormal findings on chest CT. Complications included acute respiratory distress syndrome (12 [29%]), RNAaemia (six [15%]), acute cardiac injury (five [12%]) and secondary infection (four [10%]). 13 (32%) patients were admitted to an ICU and six (15%) died. Compared with non-ICU patients, ICU patients had higher plasma levels of IL2, IL7, IL10, GSCF, IP10, MCP1, MIP1A, and TNFα.”
*(Dyspnoea means shortness of breath, haemoptysis means coughing up blood)
We Do Not Yet Know the Full Death Rate in China
The article above cites 15% mortality rate – but those cases are going to have been the worst cases presenting leading to suspicion of infection. The death rate outside China appears to be much lower than within China, which is at least 2% but according to some reports is in the double digits. The per-case death rate is hard to know because we do not know the accurate full number of people infected, and we also have to rely on death rate estimates from China via the WHO.
This website is going to be key to determining whether the death rate outside of China will catch up to the 2+% rate seen in China.
Right now the website reports 31,481 cases with 638 deaths, with 4,824 in critical condition, and 1,563 recovered. Unofficial reports of mass fatalities across Wuhei have many people convinced that the official death toll is unreliable.
Watch the Per-Case Fatality Rate Outside of China
Outside of China the apparent per-case fatality rate is still zero, with all deaths outside of China being two cases that originated in Wuhan and traveled outside of the country to Hong Kong and Phillipines. A reported death of a 22-year male in Malaysia reported to be infected with coronavirus has not been confirmed.
How will we know?
Watch the death rates in the people who have left China who are currently in quarantine.
The next two weeks will inform the world of the immediate threat of serious, deadly pandemic, or if, as I speculated, the Chinese or Asian population is somehow sensitized to 2019-nCoV or at higher risk of fatality.
Fatality rates in countries with large SARS and MERS outbreaks will tell us if the past outbreaks sensitized specific populations.