–By Dr KK Aggarwal
Loss of Smell & Taste is not a screening test
NEJM: The American Academy of Otolaryngology — Head & Neck Surgery has proposed adding anosmia and dysgeusia to the list of screening items for potential novel coronavirus disease (COVID-19).
Anecdotally, these symptoms have been reported among some patients who’ve tested positive, and in some cases, anosmia has been reported as the only symptom.
Depression is uncommon in COVID 19
A JAMA Network Open study of 1300 healthcare workers in China (mostly Hubei province) in late January and early February found that 50% had symptoms of depression, 45% anxiety, 34% insomnia, and 72% distress. Nurses, women, frontline workers, and those in Wuhan had more severe symptoms.
The infection rate is 3.4%
No. In MMWR, researchers report details of COVID-19 cases aboard cruise ships. On the Diamond Princess, 19% of the 3700 passengers and crew were ultimately infected. Nearly half were asymptomatic when they tested positive, although many eventually developed symptoms.
Cardiac Injury uncommon in COVID-19
NEJM: No. Cardiac injury is a common complication among those hospitalized with COVID 19 and it’s associated with significantly increased mortality as per JAMA Cardiology.
Researchers studied over 400 patients hospitalized with COVID-19 in Wuhan, China. Some 20% had cardiac injury, defined as elevated cardiac biomarkers (e.g., high-sensitivity troponin).
Overall, patients with cardiac injury were more likely than those without cardiac injury to require non-invasive ventilation (46% vs. 4%) and invasive ventilation (22% vs. 4%). Cardiac-injury patients also had a higher mortality rate (51% vs. 5%). After adjustment for confounders, including acute respiratory distress syndrome, cardiac injury remained a significant predictor of mortality.
We can not predict the advantage of social distancing
A new Lancet Infectious Diseases study strengthens support for strict social distancing measures. Using simulation models, researchers in Singapore estimated the number of SARS-CoV-2 infections that would occur at 80 days after the first 100 cases of community spread were confirmed, assuming that 7.5% of infections were asymptomatic.
In a scenario when the virus was least infectious (assuming each case infects another 1.5 people), a median 279,000 infections would occur by day 80. This would decrease with increasing social distancing measures, dropping to 1800 when all of the following were enacted: isolation of infected individuals plus family quarantine, workplace distancing, and school closures.
Of note, assuming a more infectious virus (one case infects another 2.5 people), there would be over 1.2 million infections at day 80 with no social distancing measures — and 258,000 with all measures in place.
Italy 7.2% mortality is not true
A JAMA viewpoint looks at the high case-fatality rate in Italy — 7.2% as of mid-March.
The authors note this could be related to three factors: 1) nearly one-fourth of Italy’s population is age 65 and older; 2) some deaths may have been due to comorbid illness rather than the SARS-CoV-2 infection; and 3) mild and asymptomatic cases were rarely tested after late February and thus were not included in the denominator.
But even then 7.2% in symptomatic cases the mortality rate is higher
Undocumented COVID-19 Infections are linked to Transmission
NEJM, Science 2020 Mar 16: No, it’s a hidden Disaster. IIn China, undocumented infections fueled the rapid early spread of SARS-CoV-2. The proportion of individuals infected with SARS-CoV-2 who have minimal symptoms is an important determinant of the pathogen’s pandemic potential, as these infections are likely to go undiagnosed.
Investigators used mathematical modeling to estimate the number of undocumented infections and their contribution to SARS-CoV-2 transmission in China.
Subjects were categorized into two groups: those with symptoms severe enough to elicit care-seeking and a documented COVID-19 diagnosis, and those with undocumented infections. The model also accounted for changes in human mobility between cities based on recent historic data adjusted for the escalating restrictions on such movement.
At the beginning of the epidemic, the estimated basic reproductive number (R0) was 2.38 and the percentage of undocumented infections was 86.0%.
Undocumented infections were estimated to cause 86.2% of all infections. Later in the epidemic and with augmented testing, the proportion of undocumented infections fell to 35%, and the R0 dropped to 1.36 and then to 0.99 as restrictions on geographic movement tightened.
Lung involvement is unilateral’
No. Radiology 2020 Apr: In a report from a single hospital in Shanghai, China, researchers reviewed the key initial CT findings in 51 consecutive patients who were hospitalized with COVID-19. All patients had thin-section noncontrast scans. Mean age was 49 (range, 16–79), and median time from symptom onset to CT was 4 days.
Nearly all patients presented with extensive multifocal involvement; abnormalities were bilateral in 86% of cases. Lesions were particularly evident in the lower lobes, posterior lung fields, and peripheral lung zones. Three quarters of patients had ≥3 involved lobes.
Various combinations of pure ground-glass opacities (GGOs), GGOs plus reticular or interlobular septal thickening, and GGOs plus consolidation were common. GGOs predominated in patients whose symptoms started ≤4 days before CT, and areas of consolidation became increasingly evident in those with >4 days of symptoms.
Pleural effusion is common in COVID 19
No. Only four patients had pleural effusions. [Radiology 2020 Apr:]
((The writer is President, CMAAO, HCFI and Past national President IMA))
