Why Experts Suspect More Cases in China and Why the U.S. Has More Cases Than it Realizes
The close relative of SARS appeared out of thin air, poised to descend on humanity like wildfire. Then, just as abruptly as cases had appeared, they disappeared — the reports, not the sick people, it would seem.
January 20, 2020 Updated January 21
E. Rosalie Li, interdisciplinary public health Johns Hopkins Bloomberg School of Public Health
- Why Experts Suspect More Cases in China and Why the U.S. Has More Cases Than it Realizes
- They called it Pneumonia of Unknown Etiology, but the mystery illness didn’t stay unknown for long.
- Accounts of the voyaging virus, now called 2019-nCoV, surfaced in Thailand on Jan. 14, 2020.
- These cases may constitute enough evidence to consider the possibility of human-to-human transmission, though it’s not a confirmation.
- How did nCoV infect people outside the market?
- Depending on when this virus spilled over and how well it moves person-to-person, it may already be spreading quietly around the world.
- The past is prologue.
- Note about updates
They called it Pneumonia of Unknown Etiology, but the mystery illness didn’t stay unknown for long.
The close relative of SARS appeared out of thin air, poised to descend on humanity like wildfire. Then, just as abruptly as cases had appeared, they disappeared — the reports, not the sick people, it would seem. A week later, cases arose in Thailand, Japan, Korea, and the U.S.
China, believing animal markets to be the source, shut them down for cleaning on Jan. 1, 2020, but multiple cases reported they had not visited the animal markets. The Wuhan Municipal Health Commission reported 59 cases of this pneumonia on Jan. 5, 2020. Vendors at local markets were among the sick, so follow-up with anyone who had contact may be impossible, and people may be reluctant to seek help or not realize what they have.
The WHO lists 63 reported cases in China, but it is unclear whether the country officially confirms it. Appearing as fever, chill, and muscle pain, the virus complicated breathing in the original outbreak victims. Doctors found fluid called “pulmonary infiltrates” in their lungs, a substance that is denser than air, often blood and pus.
China reports no cases after Jan. 3 in a Jan 11 statement, but Japan, Thailand, and now Korea all confirm cases of travelers to China (Wuhan Municipal Health Commission, 2020; WHO, 2020).
Accounts of the voyaging virus, now called 2019-nCoV, surfaced in Thailand on Jan. 14, 2020.
The woman flew from Wuhan City, China, to Thailand in a packed airplane on Jan. 8, 2020. Monitoring continues for at least 182 people who met the woman.
Japan also found the virus in a Japanese citizen who recently traveled to Wuhan City, China. DNA testing identified it as 2019-nCoV. Hirofumi Umeda from the Infectious Diseases Information Division in Japan confirmed the details of the cases on Jan. 15, 2020.
The Korean case today casts doubt on the Chinese report of no new infections. None report traveling to the animal markets, not the Korean woman or Japanese or Thai people.
The Korean case showed symptoms starting Jan 18 in Wuhan City, China, where a doctor diagnosed the woman with a cold before she traveled to Korea through Incheon International Airport. The Korea Centers for Disease Control found the virus through DNA testing (WHO, 2020).
These cases may constitute enough evidence to consider the possibility of human-to-human transmission, though it’s not a confirmation.
Most worrying, the Wuhan doctor diagnosed a Korean woman on Jan. 18 with a cold (WHO, 2020). How many more cases are there?
The estimated numbers exponentially outnumber China’s reported incidents, and SARS makes clear that we must be cautious about the reliability of reporting.
The dates of infection and travel should give pause.
How did nCoV infect people outside the market?
Potentially, human-to-human like SARS. SARS Coronavirus incubation took 4 to 6 days, with extremes of 2 to 14 days. That suggests this virus has already spread into the community, meaning we must contemplate the possibility of many more cases in Asia and the U.S. Cases almost certainly extend beyond the recognized number.
Air droplets can suspend in the air for hours after an infected person has left. Finding everyone who trekked through airports seems unlikely. SARS had an infamous ability to capitalize on super-spreaders. An airplane with one case could become an airplane with tens of cases by the flight’s end.
Nothing indicates that mild infections cannot happen, meaning infected people may be totally unaware. This is most worrying given that a Wuhan doctor diagnosed the woman on Jan. 18 with a cold. How could he have missed this? Who else has been missed?
The expected numbers are much higher than the numbers reported, which has potentially grim implications.
Depending on when this virus spilled over and how well it moves person-to-person, it may already be spreading quietly around the world.
Imperial College London, a leader in global epidemiology, published a report on Jan. 17 that affirmed my fear — only a student, I lack confidence in my conclusions:
The report estimated 1,723 cases, assuming Jan 12 as the latest onset date, and included assumptions on traffic through the airport based on averages.
The cases in Korea, Japan, and Thailand among people who traveled to China and the incubation of SARS leaves one of three possibilities:
The past is prologue.
The body would often slump to one side from a sitting position after someone died of the “Spanish Flu.” A bloody froth would drain from the nose and mouth, pooling on the ground. People infected with the same virus watched as they sat lining the hospital hallways and awaited care that would never come.
By the pandemic’s end in 1920, 50–100 million people had perished, and there is little doubt it will happen again. The pandemic the world has yet to forget— that is what floods my mind as I skim reports of a novel virus in Asia. We are not prepared.
Note about updates
- Bogoch, Isaac I, Alexander Watts, Andrea Thomas-Bachli, Carmen Huber, Moritz U G Kraemer, and Kamran Khan. 2020. “Pneumonia of Unknown Etiology in Wuhan, China: Potential for International Spread Via Commercial Air Travel”. Toronto General Hospital.
- Cauchemez, Simon, Christophe Fraser, Maria D. Van Kerkhove, Christl A. Donnelly, Steven Riley, Andrew Rambaut, Vincent Enouf, Sylvie van der Werf, and Neil M. Ferguson. 2014. “Middle East Respiratory Syndrome Coronavirus: Quantification of the Extent of the Epidemic, Surveillance Biases, and Transmissibility.” The Lancet Infectious Diseases 14 (1): 50–56. https://doi.org/10.1016/S1473-3099(13)70304-9.
- Department of communicable disease surveillance and response, surveillance and response, department of communicable disease. Consensus Document on the Epidemiology of Severe Acute Respiratory Syndrome (SARS). WHO/CDS/CSR/GAR; 2003. https://www.who.int/csr/sars/en/WHOconsensus.pdf.
- Donnelly, Christl A., Azra C. Ghani, Gabriel M. Leung, Anthony J. Hedley, Christophe Fraser, Steven Riley, Laith J. Abu-Raddad, et al. 2003. “Epidemiological Determinants of Spread of Causal Agent of Severe Acute Respiratory Syndrome in Hong Kong.” Lancet 361 (9371): 1761–66. https://doi.org/10.1016/S0140-6736(03)13410-1.
- Imai, Natsuko, Ilaria Dorigatti, Anne Cori, Steven Riley, and Neil M Ferguson. 2020. “Estimating the Potential Total Number of Novel Coronavirus Cases in Wuhan City , China,” no. January: 1–4.
- Natsuko Imai, Ilaria Dorigatti, Anne Cori, Steven Riley, Neil M. Ferguson. Estimating the potential total number of novel Coronavirus cases in Wuhan City, China. Imperial College London (17–01–2020), doi: https://doi.org/10.25561/77149
- Nickol, Michaela E., and Jason Kindrachuk. 2019. “A Year of Terror and a Century of Reflection: Perspectives on the Great Influenza Pandemic of 1918–1919.” BMC Infectious Diseases. https://doi.org/10.1186/s12879-019-3750-8.
- Schoeman, Dewald, and Burtram C. Fielding. 2019. “Coronavirus Envelope Protein: Current Knowledge.” Virology Journal 16 (1): 0–22. https://doi.org/10.1186/s12985-019-1182-0.
- World Health Organization. 2020. “WHO | Novel Coronavirus — Republic of Korea (Ex-China).”
- World Health Organization. 2020. “WHO | Novel Coronavirus — China.” WHO. World Health Organization.