|LETTER TO THE EDITOR
|Year : 2020 | Volume
| Issue : 5 | Page : 569-570
COVID-19: The curious case of the dog that did not bark – Some insights
Technical Adviser, The Maharashtra State Anti TB Association, Mumbai, Maharashtra, India
|Date of Submission||11-May-2020|
|Date of Decision||11-May-2020|
|Date of Acceptance||11-May-2020|
|Date of Web Publication||7-Sep-2020|
2B Saurabh, 24E Sarojini Road, Santacruz West, Mumbai - 400 054, Maharashtra
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Dholakia Y. COVID-19: The curious case of the dog that did not bark – Some insights. Med J DY Patil Vidyapeeth 2020;13:569-70
Banerjee, in his editorial, has pertinently raised the enigma surrounding the global COVID-19 pandemic situation. He has postulated the issue of poor transmission and low mortality in overcrowded geographies to be the result of different demography, low body mass index, and prior exposure to other coronaviruses.
Truly, disease transmission depends on the demography of a particular population. These geographies have a predominantly young population, and this may be one of the reasons. It may also be that they are still in the early phase of the epidemic and early lockdown has prevented the elderly from infection.
Case detection depends on the amount of testing that is done. In South Asia, especially in the Indian subcontinent, the testing algorithms are very strict and very few infected individuals (those who are symptomatic, have a history of travel or contact) are tested. This results in underreporting and missing cases and in transmission of infection. We do know that transmission occurs in the clinical latency stage before symptoms develop.
Transmission of COVID-19 is associated with host-related immune dysregulation. The younger population, although not at low risk of infection, has milder symptoms due to lesser inflammation.
One of the most remarkable features of antiviral immunity is that it shows adaptation in its strategy to the stages of human life. The type of response to COVID-19 infection is more inflammatory, and aging is a condition associated with cytokine dysregulation and reduction in T-cells. Patients on anti-inflammatory medicines such as those with rheumatoid arthritis and such conditions are presumed to have a lower risk of fulminant/severe presentation.
Another interesting factor that seems to contribute to the differential presentation among geographical regions is exhibition of gene-level mutations which may affect the viral genomes, conferring unique infection, facilitation of transmission, virulence, and immunogenic features to the virus, as has been demonstrated in the Indian strain of severe acute respiratory syndrome coronavirus 2 (COVID-19).
The natural history of COVID-19 is evolving and so is the knowledge of the pathogenesis of the various clinical conditions evolving due to the infection. Many hypotheses are being studied including that of the role of coagulopathy,, which can cause a reduction or stoppage of blood supply to vital organs leading to their failure. Care modules are constantly evolving.
Finally, in the absence of preventive or curative therapy, the natural history of COVID-19 infection from transmission to death, in those few who succumb to the infection, is short. It is essential to study the natural history through longitudinal cohort studies of asymptomatic and those who survive the infection after developing symptoms.
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Conflicts of interest
There are no conflicts of interest.
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