Piryani Rano Mal, Piryani Suneel, Piryani Shomeeta & Muzaherul Huq
As of April 10, 2020 (GMT+0), Covid-19 is affecting 210 countries and territories around the world and 2 international conveyances; the reported total new cases are 1,6 98,881, deaths 102, 687.
Covid-19 is caused by a novel coronavirus (2019-nCoV); an outbreak of viral pneumonia centered around Wuhan, Hubei, China reported in January 2020. There were two other outbreaks due to coronavirus in recent past; one is Middle East Respiratory Syndrome (MERS) and another Severe Acute Respiratory Syndrome (SARS). MERS caused by MERS-CoV is a viral respiratory illness first reported in Saudi Arabia in 2012. SARS caused by SARS-CoV can produce a severe viral respiratory illness reported first in Asia in February 2003.
All these three diseases are transmitted from close person to person contact. (3)Human-to-human transmission of SARS-CoV-2 (Covid-19) occurs mainly between family members and also to relatives, friends, coworkers or healthcare staff who intimately contacted with symptomatic patient or asymptomatic or carriers during incubation period. By contrast, the transmission of SARS-CoV and MERS-CoV is reported to occur mainly through nosocomial transmission. (4, 5) Covid-19 spreads much faster than MERS and SARS. For first 1000 people to be get infected with MERS took 903 days, SARS 130 days and Covid-19 took 48 days.
No specific vaccine is available for prevention of disease and specific drugs to treat the Covid-19 disease or use drugs for prophylaxis purpose.
In epidemic or pandemic of infectious diseases like Covid-19, testing is essential as to see who, what, where, why and how many people are infected by one Covid=19 patient. If there is poor testing then infected people can spread the virus to hundreds other people if not isolated and quarantined. If good testing along with adequate quarantine then spread is limited. There are two types of tests available for Covid-19, test directly detecting virus from swabs of nose and throat and tests for detection of antibodies from blood sample. Comparison is shown in Table 1.
Table 1: Comparison of lab tests for detection of (2019-nCoV, Covid-19)
If antibody detection tests are used, then after 7 days of infection antibodies will be detected in patient’s serum; by that time, patient might have infected many. The minimum incubation period of Covid-19 is three days. Patient remains asymptomatic during that period and infecting people. Antibody tests are commonly used to test for exposure to the viruses. These tests could help disclose people who have been exposed to the virus and are now likely immune and could go back to work and resume their normal lives. They may also provide information regarding prevalence of infection.
The World Health Organization (WHO) supports a policy of widespread testing. But the policies about lab testing for diagnosis around the world vary and there seem to be opinions in support of the different approaches – largely due to supplies, shortages and priorities, stage of epidemic, financial constraints. Testing is essential as instructing people with mild symptoms just to stay home will lead to more infections in the household and community. If tested and found positive, people can either be isolated in an identified facility or put on strict home isolation ensuring that they are aware of having disease and willing to adhere to protocol instructions. In case of limited resources and if healthcare system is overloaded, limit the visit of non-sick people to health facilities, so as to minimize the risk of contagion but have a focused strategy for.
Data on Covid-19 testing report updated on April 4, 2020 reveals that if testing increases, then it will be known to policy makers and healthcare professionals where the epidemic is and what next step likely to be taken to contain the pandemic globally or epidemic/outbreak in particular country or particular region, province, city or village of the country.
In conclusion, as per WHO suggestion countries need to increase the testing for Covid-19. Without widespread testing it is difficult to know how the pandemic is spreading and how appropriate are our responses and whether to escalate the responses or continue same strategy or scale down interventions. The tests directly detecting virus are essential to diagnose the Covid-19 patients and for their subsequent management as to declare the patient recovered and trace the contacts, test and then isolate/quarantine as to prevent further spread of infection.
The antibodies tests give detail about the prevalence of a disease in a population by ascertaining persons who have developed antibodies against virus.
(Piryani Rano Mal, Professor of Internal Medicine, Head Department of Internal Medicine and Chief Coordinator- Health Professions Training Committee, Coordinator COVID-19 Task Committee, Universal College of Medical Sciences, Bhairahawa, Nepal,?* Piryani Suneel, Research Specialist, Department of Community Health Sciences, Aga Khan University Karachi Pakistan, * Piryani Shomeeta, Senior Radiologist, Memon Hospital Karachi Pakistan, * Muzaherul Huq, Former Regional Advisor, WHO SERO Bangladesh).