Can 1 positive person spread infection only to 3 people?: Covid-19 myths busted
A South Korean patient who is linked to spreading the coronavirus to over 1,000 people is being used as an example of why social distancing is so important.
— By Dr KK Aggarwal
Doubling of cases in one day can be ignored
No. Doubling time is 7 days. If cases suddenly double, it may be the first indication of community spread. For example on 20th March India has jumped to more than double cases then the previous day, is a sign of worry.
One positive person can spread infection only to 3 people
No. The attack rate or transmissibility (how rapidly the disease spreads) of a virus is indicated by its reproductive number (Ro, pronounced R-nought or r-zero), which represents the average number of people to which a single infected person will transmit the virus.
WHO’s estimated (on Jan. 23) Ro to be between 1.4 and 2.5. 
Other studies have estimated a Ro between 3.6 -4.0, and between 2.24- 3.58.
Preliminary studies had estimated Ro to be between 1.5 and 3.5.
An outbreak with a reproductive number of below 1 will gradually disappear.
For comparison, the Ro for the common flu is 1.3 and for SARS it was 2.0.
So, with this one person can only infect 3-34 people.
But, we know that HIV with Gonorrhoea combination spread HIV more rapidly than a person with HIV alone. The fast spreader is called super spreader.
A South Korean patient who is linked to spreading the coronavirus to over 1,000 people is being used as an example of why social distancing is so important. The Asian country saw a jump from hundreds of cases to thousands within days with a super spreader labelled “patient 31” linked to 1,160 cases. In the days before the woman’s diagnosis she, a member of a large cult called Shincheonji, had multiple contacts with large gatherings.
Cloth can not be sued as a mask
Thailand’s health authorities are encouraging people to make cloth face masks at home to guard against the spread of the coronavirus. Cloth masks are enough to prevent people from catching the virus via droplets from coughing or sneezing.
The droplet from coughing and sneezing is around five microns and we have tested already that cloth masks can protect against droplets bigger than one micron. The masks needed to be washed daily. It is better than nothing because at least it can protect me from people’s saliva in close contact.
Cloth can not be reused after ironing it
For the purpose of using the cloth to protect the hands touching the mouth, one can use cloth mask after ironing it.
China delayed informing the WHO
While there were 300 cases and 5 deaths with SARS before the Chinese government reported it to the World Health Organization, there were only 27 cases and no deaths with COVID-19 before it was reported to that agency.
The virus only present with mild or serious cases?
No. Stages can be
1. Asymptomatic mild
2. Symptomatic mild
3. Moderate oxygen independent pneumonia
4. Moderate oxygen dependant pneumonia
5. Severe pneumonia with ARDS, sepsis and septic shock.
6. Severe critical pneumonia: Ventilator dependent
At entry of any gate any person can take thermal temperature
No. Use of no-touch thermometers, thermal imaging cameras, and limited observation and questioning, all require maintaining a spatial distance of at least 1 m. The person doing it must be trained?
Presence of GI symptoms has no significance in COVID 19
Patients with gastrointestinal (GI) symptoms who were admitted to the hospital and were diagnosed with COVID-19 were more likely to have severe disease than patients who did not have GI symptoms, according to findings published March 18 in the American Journal of Gastroenterology.
Self-quarantining and self-monitoring are same
No. Both strategies aim to keep people who have been exposed, or might have been exposed, away from others as much as possible for a period. That has generally meant 14 days, considered the incubation period of COVID-19, although symptoms can appear within a few days of exposure.
Self-monitoring might include regularly checking temperature and watching for signs of a respiratory illness, such as fever, cough or shortness of breath, according to the Centers for Disease Control and Prevention.
It also involves limiting interaction with others.
Say, for example you attended a large conference where someone was later found to be positive for the coronavirus, even if you were not in close contact with that person.
Say, the person speaking at the podium was later diagnosed and you were in the audience ― you’re not considered at risk. Those people may want to strictly self-monitor.
But if you had a long conversation [with that person] or that person coughed or sneezed on you, that’s different.
Self-quarantine is a step up from self-monitoring because the person at risk of infection — even though they still don’t have symptoms ― had a higher chance of exposure.
Doctors are less likely to get COVID 19
No. Health care provider infections in China was 3.8% with 0.3% deaths. Recent death was of Stephen M. Schwartz, MD, PhD, a pioneer in the field of vascular biology and a longtime professor of pathology at the University of Washington (UW) School of Medicine, Seattle, died March 17 after being hospitalized with COVID-19. He was 78.
((The writer is President, CMAAO, HCFI and Past national President IMA))