The document provides information on potential weaknesses of Covid-19 that may limit its impact and spread, as well as expert advice and tips for healthcare workers on safety. Some key points include that Covid-19 has a low mutation rate, can only spread human to human, does not directly target immune cells, and its evolution is unlikely to make it more deadly over time. Social distancing and isolation are effective strategies. Healthcare workers should focus on hand hygiene, proper mask usage, limiting patient contact, and maintaining distance from others to stay safe.

1. Seven potential weaknesses of Covid-19.
1. Mutation rates: Covid-19 does not appear to have a very high mutation rate. As
such, scientists believe that future vaccines and drugs will be efficient.
2. Transmission: Covid-19 does not appear to have intermediate hosts so that it
can be spread only from human to human. Social isolation should be efficient if
well implemented and respected.
3. Targeted cells: It is a respiratory virus, and it does not directly target the immune
cells so that people with a healthy immune system can recover.
4. Persistence in the environment: Although it can persist in the environment for
a few days under certain conditions, Covid-19 can be easily destroyed by
washing your hands with soap.
5. Evolution: it is unlikely that Covid-19 is going to become more deadly in time.
Viruses tend to "learn" to cohabit with their host and not to kill their host fast.
Natural selection favours strains that can disperse and infect more individuals
rather than strains that kill their infected host. A strain of the virus that quickly
kills its host is not able to efficiently replicate and disperse.
6. Herd immunity: Infection rates tend to slow down when sufficient individuals in
a population acquire immunity (got the virus and recovered). The recovered
individuals with immunity no longer act as vectors of transmission for the naïve
(never exposed) individuals. However, this will take time since at the moment
we are a naïve population to this virus. This is the reason social isolation is
necessary.
7. One small note on herd immunity: There is emerging evidence that countries
with long-term vaccination programs against tuberculosis have much lower
death rates for COVID-19. It looks like vaccination for tuberculosis could
provide some immunity against COVID-19. The study is not published yet and
is based only on reported numbers (no experimental approach), but it looks
promising
-Prof. Melania Cristescu, McGill University, Canada
Expert Advice – Hope and worries
1. We'll live with C19 for months, Let's not deny or panic. Do not make our lives
useless. Let's learn to be happy and live with this fact.
2. The virus won't reduce its effect in summer. It's summer in Brazil and Argentina,
but the virus is spreading fast.
3. You can't destroy C19 viruses that have penetrated the cells drinking too much
water - you'll just go to the bathroom often.

2. 4. Washing hands and maintaining a 2 m protection distance is the best method
for protecting against the virus. If you don't have a C19th patient at home,
there's no need to disinfect the surfaces at your house.
5. Package cargo, gas pumps, shopping carts or ATM does not cause infection.
Wash your hands, live your life as usual.
6. C19 is not a food infection. It is associated with drops of disease like flu. There
is no demonstrated risk that C19 is transmitted by ordering food.
7. Sauna sessions don't kill C19 viruses that broke into the cell.
8. You can lose your smell with many allergies and viral infections. It is a non-
specific symptom for C19.
9. Once at home, we don't need to change our clothes urgently and shower! Purity
is a virtue, not paranoia.
10.C19 virus doesn't hang in the air. This is an infusion infection that requires close
contact. The air is clean, you can walk through the gardens (keeping your
protection distance), through the parks.
11.C19 does not distinguish race or religion, and it is transmitted to all persons.
12.It is sufficient to use normal soap against C19, not necessarily antibacterial
soap. The virus, anyway, is not a bacteria.
13.You don't have to worry about your food orders. But if you want more
processed, you can heat them up a little bit in the microwave.
14.The chance to bring C19 home with your shoes and as a result of getting sick
is the same as being struck by lightning twice a day. I've been working against
viruses for 20 years - drip infections don't spread like that.
15.You can't be protected from the virus by taking vinegar, sugar, juice and ginger!
16.Wearing gloves is a bad idea; the virus can accumulate into the glove; it can
easily be transmitted if you touch your face. You better wash your hands".
-Dr. Fahem Yunus, University of Maryland USA
Tips for health care workers
"The most important defence that is going to protect you from the Coronavirus is still
common sense with some soap, and not the N95 mask !"
If you have a habit of touching the face with your unsensitized hand, eating snacks
with a lowered mask, repositioning the mask with pinching on the front side, then
probably you are already infected. You are done!

3. 1. First, know your enemy-simple two rules-the virus spreads through the air at a very
close distance or through contact. All your moves will be based on this information
with eternal vigilance with improvement in each moment.
2. First, you need to relax; understand the mortality figures you see in the newspapers.
The virus runs an asymptomatic course, probably in the majority(1).⁠ Imagine the virus
is sprayed on 100 peoples' nose. 60 of them will never develop any symptoms and out
of the rest 40, 20 may develop severe symptoms requiring hospital admission and out
of these last 20, one person dies. The hospital will report the 'case fatality rate' as
1/20= 5%. Note that only 20 reached the hospital to get the testing done. The actual
risk of death is 1/100, which is called the 'infection fatality rate'. Its very difficult to find
the figure, as nobody knows the asymptomatic infection rates. For the current Corona
epidemic it is estimated(2)⁠ by mathematicians to be around 0.5%. So don't worry,
99.5% of the time, odds are in favour.
3. Being a health care worker (HCW), are you at higher risk of complications compared
to the public? Probably no. All the complications depend on your age, and not the
number of viruses that goes inside. No significantly different viral loads in nasal swabs
were observed between symptomatic and asymptomatic patients with SARS Cov-2
infection.(3)
4. During a cough or sneeze, salivary spray contain different types of particles. The
larger respiratory 'droplets', are >5-10 μm, and travel only 3-6 feet due to their weight.
The transmission through this is called 'droplet transmission'. Tiny 'droplet nuclei',
<5μm in diameter, can remain suspended in the air for a long time. Travel greater than
1-meter Airborne transmission.In an analysis by WHO and China of 75,465 COVID-
19 cases in China, the airborne transmission was not reported. (4) Now let the fear
factor disappear, and you can think clearly and calmly about the defence.
5. N95 vs Surgical mask vs cloth masks- choose the right shield at the right time.
Hence use a surgical mask when you are sitting in OPD or taking rounds, and N95 (to
filter small droplet nuclei) only when you are doing or near to an aerosol-generating
procedure. Wear a cloth mask when you are in the community, as the purpose is to
prevent transmission from you. Use resources intelligently and effectively. You may
require it for the big and long battle, just in case.
6. Don't underestimate the surgical mask. It was found good even when intubating.(5)⁠⁠
7. Refrain yourself from lowering mask for making phone calls, while talking to your
colleague, or inside your OPD. Refrain from touching the front side. Refrain yourself
from saying that the mask is suffocating (it is and will be; you need to compromise).

4. 8. When you remove the mask for taking a tea, remove the lower tie first. Don't touch
the front side. Keep the mask inside your table drawer on a tissue paper, frontside
down carefully. Practice hand hygiene after handling it- after removing or putting it
back.
9. Make sure that, all around you are using the mask properly. If a friend lowers his
mask for chatting with you (with a sigh of relief on his face), he is ready to shoot 3000
droplets in 5 minutes into air. Shoot him before that.
10. Don't go near your colleagues wearing a mask with nose exposed, over the head,
under the chin. Preach to them from a distance.
11. Don't go to canteen or mess room; bring food and eat inside your room or order
food. Ask your nurse or assistant to eat inside your room too. Don't talk during
chewing.
12. Practice hand hygiene after each patient. Ask your colleague to monitor you.
Watch your colleagues and give feedback; they shouldn't get infected so that you also
won't.
13. Inside the OPD, install a good exhaust fan. Maintain good air circulation inside the
room. Keep the temperature of AC to the highest tolerable; droplet won't travel towards
the sky. They will settle on the floor soon. Install an exhaust inside the toilet also.
14. Corona can enter through eyes. Always wear a mask and an eye visor/ face shield
right from the parking lot of hospital (personal recommendation). Do not remove it
even while talking to your friend or nurse.
15. Avoid lift and take the stairs. If you are using a lift, stay facing the walls keeping
social distancing.
16. Always insist all the patients wear a mask.
17. Tell the front desk to advise to wear a mask to whoever calls for an appointment.
18. Start a separate fever clinic at some corner of your hospital. A doctor with full PPE
can see patients here. Arrange a separate pharmacy for them.
19. Don't go near the patients every time, unless absolutely needed. Turn their head
to the opposite side while auscultating, taking blood pressure, giving injections or
drawing blood.
20. Limit the number of nurse visit to patients room by clubbing all the activities
together- like checking vitals and delivering food and medicine.

5. 21. Minimize transport of the patient inside the hospital, check the PPE of the
accompanied persons.
22. All other staff stay outside the operation room, while the patient is being intubated
and extubated during anaesthesia.
23. Try to settle thing over the phone as far as possible. Use Telemedicine. Don't offer
an excuse; learn it.
24. Maintain social distancing inside the hospital like the same poles of a magnet. The
droplets travel at a very close distance only.
25. At home, don't go near your parents. Ask them to wear a mask. If you happen to
cross their path, keep your breath in slow inspiration.
-Dr.Rakesh T Parakadavathu, Kerala, India
References:
1. Day M. Covid-19: identifying and isolating asymptomatic people helped eliminate the virus
in an Italian village. BMJ. 2020 Mar 23;368:m1165.
2. Russell TW, Hellewell J, Jarvis CI, van-Zandvoort K, Abbott S, Ratnayake R, et al.
Estimating the infection and case fatality ratio for COVID-19 using age-adjusted data from
the outbreak on the Diamond Princess cruise ship. medRxiv. 2020 Mar
9;2020.03.05.20031773.
3. D C, M T, F R, V D, M A, P P, et al. The early phase of the COVID-19 outbreak in Lombardy,
Italy. 2020 Mar 20;
4. Aylward, Bruce (WHO); Liang W (PRC). Report of the WHO-China Joint Mission on
Coronavirus Disease 2019 (COVID-19). WHO-China Jt Mission Coronavirus Dis 2019.
2020;2019(February):16–24.
5. Ng K, Poon BH, Kiat Puar TH, Shan Quah JL, Loh WJ, Wong YJ, et al. COVID-19 and the
Risk to Health Care Workers: A Case Report. Ann Intern Med. 2020 Mar 16;