[AZT]

Originally Posted by vivek95

He had no symptoms whatsoever all these days. However, due to fear alone, he got tested himself for COVID-19 on day 21 from a reputed private lab in Mumbai and turns out he is "positive" !
-- Dr. Vivek

Some questions regarding this:
1. Do we have any clarity on how long an asymptomatic person can be contagious.

2. Since most people develop immunity to this, are you still contagious after developing the immunity.

3. Is it possible for a person to test negative on say day 7 but test positive on day 14, is there any time period for which you need to be infected for it to show on the test.

[jayguar]

Originally Posted by AZT

2. Since most people develop immunity to this, are you still contagious after developing the immunity.

Not sure if it can be called immunity. Wouldn't the person be a carrier who can still spread unknowingly? I could be wrong here.

Originally Posted by AZT

3. Is it possible for a person to test negative on say day 7 but test positive on day 14, is there any time period for which you need to be infected for it to show on the test.

I had this exact same question some time ago but we didn't not have a proper answer for that back then, and still not sure if there have been cases like that now.

[naveenroy]

A bit of good news from a doctor friend - about the BCG vaccine that we still give babies in India - though this has been stopped in other countries including USA.

https://www.forbes.com/sites/ericmac...virus-pandemic

[PaddleShifter]

Originally Posted by vsathyap

Can the experts and doctors advise on how to handle groceries and vegetables, fruits, flowers, green leafy vegetables, etc? These things pass through a lot of hands before they make their way into our homes. Will a simple cold water wash suffice for vegetable and fruit? What about packed stuff like biscuits chips etc? What if someone with covid has coughed or sneezed on these items?

There is no specific advisory or evidence regarding food borne transmission in my knowledge. My advise would be to wash all vegetables, fruits, flowers, green leafy vegetables in running water. Keep a separate utensil ready, wash your hands with soap and water, then start washing the fruits, vegetables and transfer washed ones in the separate utensil. This is what I am doing.

For packed items such as biscuits, chips, fruit cakes, the paranoid me is washing them gently with small amount of soap and water (for real) while they are still sealed. No water or soap goes inside. Be advised, soap must not come in contact with food items. Also, I am careful in selecting the food packets as I do not buy the ones that have a flimsy packing or if the packing seems compromised as it will not allow me to wash such packets.

Originally Posted by vibbs

Doc, my heart sank the moment I read that post! Wonder how many people could be infected by this one guy. He was quarantined but his family members were not!
:(
My worry for my parents and family back in India grows. More so since I am not with them!

Its good not to read too much about individual cases. Everything will be fine soon and our lives will be back to normal. Do not stress about what is not in our hands but focus on things that are in our control (social distancing, general precautions etc.)

Originally Posted by AZT

Some questions regarding this:
1. Do we have any clarity on how long an asymptomatic person can be contagious.
2. Since most people develop immunity to this, are you still contagious after developing the immunity.
3. Is it possible for a person to test negative on say day 7 but test positive on day 14, is there any time period for which you need to be infected for it to show on the test.

Answer 1: There is no information regarding this on CDC website. The following is what they mention as of now:
"The onset and duration of viral shedding and the period of infectiousness for COVID-19 are not yet known. It is possible that SARS-CoV-2 RNA may be detectable in the upper or lower respiratory tract for weeks after illness onset, similar to infections with MERS-CoV and SARS-CoV. However, detection of viral RNA does not necessarily mean that infectious virus is present. There are reports of asymptomatic infections (detection of virus with no development of symptoms) and pre-symptomatic infections (detection of virus prior to development of symptoms) with SARS-CoV-2, but their role in transmission is not yet known. Based on existing literature, the incubation period (the time from exposure to development of symptoms) of SARS-CoV-2 and other coronaviruses (e.g. MERS-CoV, SARS-CoV) ranges from 2–14 days."
https://www.cdc.gov/coronavirus/2019-ncov/hcp/faq.html


Answer 2: This is again a tricky question to answer "as of now". I say as of now, because the possibility of re-infections in recovered patients has still not been eliminated by CDC. So answering the duration of infectivity is even more challenging. Normally, by the time a patient develops immunity, the infectivity is reduced to a substantial extent but it is again a complex interaction of the virus and the immune system that can not be generalized to all infectious agents. In context of immunity, I am sharing links to some news articles that are simple enough to comprehend by anyone.
https://abcnews.go.com/Health/immuni...ry?id=69756590
https://www.nationalgeographic.com/s...us-we-need-it/

For a more curious reader who is willing to spend time understanding virus-host interaction in details, this book chapter is relevant:
https://www.ncbi.nlm.nih.gov/books/NBK8423/

Answer 3 (simple explanation): The two commonest methods of detecting a viral infection is either by detecting the virus (or its DNA/RNA) or detecting the antibodies in the body as that is an evidence that the person is/was infected by that virus and thus developed antibodies.

The present method of COVID-19 testing is based on virus detection so it can be detected earlier (it takes time for antibodies to develop and this time frame is variable depending upon the testing method/kit and the dynamics of the virus interaction with the infected host).

Now, to answer your question, it is possible to test negative on day 7 but positive on day 14. This could be attributable to a variety of factors such as: quality of clinical specimen collected, maintenance of cold chain during specimen transport, error in testing, quality of test kit, patient related factors (variability in onset of virus shedding and its numbers in his/her respiratory secretions).
https://theprint.in/india/leh-cab-dr...d-test/385480/

Our current guidelines stated that an asymptomatic person needs to be tested once between day 5 to day 14 after contact.
https://icmr.nic.in/sites/default/fi...19_test_v3.pdf

[rohitoasis]

While the world grapples to explain to the majority of people risks of this pandemic, we have had multiple posts which have tried to spell out what we know and may not know about this virus. I think what most people understand is a visual aid. I am hoping this video by vox helps illustrate it to people. If we may have this video ratified by experts here, we could help circulate this wide enough for people to take the condition seriously.

https://youtu.be/FVIGhz3uwuQ

[doxinboy]

The Guardian, UK ran a news piece today, rather scary I should say. Here is an excrept from a doctor in Kolkata:

“Every day thousands of people gather here, seeking treatment for many infectious diseases. Last week, I noticed, hundreds of people, with many coughing, having fever and breathing problems stood on queue waiting for their turn to be examined by us,” he said.

“They stood in the queue for hours and many of them were coughing and sneezing. I have every reason to believe many were carriers of Covid-19 who spread the infection to people in that same line, who in turn are now spreading it in the community … hundred or thousand times more people should be tested for the infection. Otherwise, the coronavirus situation will turn unmanageable.”

Full piece here

The reason I posted here is because Fever Clinics have been operational in Bangalore and people might folk to it with the slightest of symptoms. I don't know what to make out of it anymore.

[warrioraks]

Dutch Scientists Find a Novel Coronavirus Early-Warning Signal

From the article - Wastewater surveillance is a well established method of detecting poliovirus and antibiotic-resistant bacteria, as well as the use of illicit and prescription medications.Sewage surveillance could also serve as early warning of the emergence and re-emergence of Covid-19 in cities

https://www.bloomberg.com/amp/news/a...-in-dutch-city

After reading the article, first thought that came to mind was - Can this approach be used in India to test at scale?

Rather than screening people individually, maybe monitor the sewage by township/locality/building to identify and quarantine highly impacted clusters. Can some of our knowledgeable folks throw some light.

[psbali]

Originally Posted by vsathyap

Can the experts and doctors advise on how to handle groceries and vegetables, fruits, flowers, green leafy vegetables, etc? These things pass through a lot of hands before they make their way into our homes. Will a simple cold water wash suffice for vegetable and fruit? What about packed stuff like biscuits chips etc? What if someone with covid has coughed or sneezed on these items?

What is going around on the internet is that Nobody knows how the virus behaves. A lot of research is going to come out as even experts are puzzled. One day they say that virus doesnt travel more than 1 mtr and today some research came out saying that the virus can travel more than 8 mtrs when an infected person sneezes or coughs.

My rule has been that if the food packet cannot be washed with soap then dont buy. As for vegetables buy only those vegetables that you can wash with soap that you use to wash hands and after cleaning your hands, surface, vegetable just peel the outer layers.

[Chetan_Rao]

Originally Posted by naveenroy

A bit of good news from a doctor friend - about the BCG vaccine that we still give babies in India - though this has been stopped in other countries including USA....

We can only hope for favorable peer review findings and encouraging field tests. It's contra-indicated for immune-suppressed people and expecting mothers, according to the article.

[naveenroy]

Originally Posted by Chetan_Rao

We can only hope for favorable peer review findings and encouraging field tests. It's contra-indicated for immune-suppressed people and expecting mothers, according to the article.

True that - a long way to go with testing. And maybe very aptly put by Nigel Curtis, head of infectious diseases research, at the Murdoch Children’s Research Institute in Melbourne - “We wouldn’t be doing this if we didn’t think that this might work,” Curtis said. “We cannot guarantee that this will work. And of course, the only way to find out is with our trial.”

https://www.bloomberg.com/news/artic...st-coronavirus

I'd take any bit of good news these days

[ninjatalli]

Originally Posted by doxinboy

The Guardian, UK ran a news piece today, rather scary I should say.

...

The reason I posted here is because Fever Clinics have been operational in Bangalore and people might folk to it with the slightest of symptoms. I don't know what to make out of it anymore.

+ 1 to this.

Also, there seems to be a heavy focus on limiting the information that is shared with the media.

[sid__kaps]

https://www.google.com/amp/s/www.ind...385-2020-04-02
All we can hope is that through a miracle, this person has not met many people, because the idea of Coronavirus spreading in Dharavi just scares me.

[sgiitk]

Any vaccine / drug we get is not extensively tested, so may be a bit of a question mark. Expediency is preferred over testing.

Also, I saw some criticism on the box about Hazmet suits. What are the options? Nothing or these relatively untested suits. What will I take, the suspect suits!

I am worried about the outbreak in Dharavi. How good can the isolation be there? Unfortunately the victim expired.

We are still in Stage II while Japan has entered Stage III. How far are we from Stage III?

[DCEite]

Originally Posted by sgiitk

.

We are still in Stage II while Japan has entered Stage III. How far are we from Stage III?

I think we are already in Stage 3 now. Dr. Vivek posted about a person with no travel history acquiring the virus. And the Dharavi slum dwellers are no international travellers either.

Which means community transmission has already happened and we are well into stage 3. The numbers, unfortunately, will only go up from here, exponentially.

[ninjatalli]

Originally Posted by sgiitk

I am worried about the outbreak in Dharavi. How good can the isolation be there? Unfortunately the victim expired.

We are still in Stage II while Japan has entered Stage III. How far are we from Stage III?

I think there are good actions being taken on the ground; how effective it is going to be will be only visible over this week or 2 going ahead.

Also there are several slum and high-rise settlements that have been put on lockdown with entry/exits being monitored very carefully (refer to my post on previous page). A friend living in a high-rise apt complex (Dosti Acres, Antop Hill) just updated that their entire apartment complex has been declared as containment area due to a positive case of a resident (he's been moved to the hospital).