COVID COVID-19 Coronavirus Containment Efforts

[Vanadium 50]

Maybe the richer people traveled to Europe more?

Lots of maybes.

• Maybe they travel abroad more (but if so, why are the airport counties low? Airport workers have at least as much contact with overseas travelers.)
• Maybe their friends do
• Maybe it's additional time on public transit
• Maybe they are more likely to seek medical assistance
• Maybe they are more likely to get tested

I would think that any model that's any good should be able to explain this.

 

[Mondayman]

1.) How would you handle this if you wanted to get them to stop coming on your property?

I would handle it with an M1 Garand and a stern "Get off my lawn".

 

[kyphysics]

Israeli COVID-19 treatment shows 100% survival rate - preliminary data

https://www.jpost.com/health-science/israeli-covid-19-treatment-shows-100-percent-survival-rate-preliminary-data-624058

Six critically ill https://www.jpost.com/coronavirus patients in Israel who are considered high-risk for mortality have been treated with Pluristem’s placenta-based cell-therapy product and survived, according to preliminary data provided by the Haifa-based company.

The patients were treated at three different Israeli medical centers for one week under the country’s compassionate use program and were suffering from acute respiratory failure and inflammatory complications associated with COVID-19. Four of the patients also demonstrated failure of other organ systems, including cardiovascular and kidney failure.

Not only have all the patients survived, according to Pluristem, but four of them showed improvement in respiratory parameters and three of them are in the advanced stages of weaning from ventilators. Moreover, two of the patients with preexisting medical conditions are showing clinical recovery in addition to the respiratory improvement.

I'll admit the 100% in the title excited me and drew me to click. Yes, the sample size is small, but at least it's something that could be a source of hope. I post these articles on possible treatments and progress, b/c I really want to my immediate family to all survive this. If the the articles ever get annoying, feel free to let me know.

Also just figure others may have some interesting commentary on treatment/vaccine development news from time to time. ...So, I post these every now and then.

Don't have the scientific background to know what they are talking about, but this was in the piece:

Pluristem’s PLX cells are “allogeneic mesenchymal-like cells that have immunomodulatory properties,” meaning they induce the immune system’s natural regulatory T cells and M2 macrophages, the company explained in a previous release. The result could be the reversal of dangerous overactivation of the immune system. This would likely reduce the fatal symptoms of pneumonia and pneumonitis (general inflammation of lung tissue).

Previous preclinical findings regarding PLX cells revealed significant therapeutic effects in animal studies of pulmonary hypertension, lung fibrosis, acute kidney injury and gastrointestinal injury.

 

[Rive]

If one looks at the map of cases in New York, one sees a remarkable correlation with affluence.

I wonder if there is a statistics about cases (not only deaths) according to country of origin?
(Ps.: I mean... Mexico has BCG vaccination policy.)

BTW Canada is surprisingly peaceful.

 

[mfb]

TOPEKA, Kan. (WIBW/AP) --- The Legislative Coordinating Council voted to overturn Gov. Laura Kelly’s newest executive order restricting the size of religious gatherings.

while also trusting them not to do anything that would put their congregation at risk. No evidence has been shown to indicate that faith leaders are violating that trust,” said House Speaker Ron Ryckman (R-Olathe)

Oh really.
https://www.msn.com/en-us/news/us/more-than-930-coronavirus-cases-in-kc-metro-with-3-new-deaths-tied-to-kck-clusters/ar-BB12lIB6:

At least 18 people linked to the Kansas East Ecclesiastical Jurisdiction’s Ministers and Workers Conference from March 16-22 have contracted the virus and two have died.
[...]
The Wyandotte County Health Department believes 150 to 200 people attended the event.
[...]
Three Coronavirus clusters in Kansas were tied to church gatherings, according to KDHE.

https://www.kansas.com/news/coronavirus/article241810656.html#adnrb=900000
https://www.kansascity.com/news/coronavirus/article241863906.html

I'll leave the absurdly obvious conclusion to readers.

 

[anorlunda]

1.) How would you handle this if you wanted to get them to stop coming on your property?

You won't like this, but maximum protection for your kids is to not allow them to go outside. That's a pain, but you can police your own kids better than someone else's kids.

My mother made me stay inside one whole summer school vacation because of a polio epidemic. As a kid, I hated it. But as an adult, when I learned how many other kids my age were killed or crippled by the polio, I was grateful. I wager that other senior PF members remember the polio epidemic in 1948(??).

 

[peanut]

I've learned from this forums that there could be several reasons why discharged patients get tested positive again. These include inaccurate tests being done or patients not being tested to confirm that they are free of the virus before being discharged. But 51 cases are too many for inaccurate tests. What do you think?

https://www.dailymail.co.uk/news/ar...d5Dxq9XNIebVe2LNS6snv376qYvbJGtExXxuRuQx5G1g0

 

[Borg]

I listen to music on YouTube but I'm really getting tired of the endless interruptions with 'influencers' that I never heard of, telling me to stay inside.

 

[jedishrfu]

I've learned from this forums that there could be several reasons why discharged patients get tested positive again. These include inaccurate tests being done or patients not being tested to confirm that they are free of the virus before being discharged. But 51 cases are too many for inaccurate tests. What do you think?

https://www.dailymail.co.uk/news/ar...d5Dxq9XNIebVe2LNS6snv376qYvbJGtExXxuRuQx5G1g0

There are also multiple strains of Coronavirus so while you may have beaten one strain, there's another right around the corner perhaps not a virulent since you've battled its cousin but still something you can get.

https://www.newscientist.com/articl...are-there-two-strains-and-is-one-more-deadly/

 

[mfb]

What do you think?

I think the Daily Mail is notoriously unreliable. Maybe it's true, maybe it's not, but their success rate is not high enough to spend time on it.

 

[kyphysics]

'It's not fancy, but it works': Mississippi doctor uses garden hose, lamp timer and electronic valve to create makeshift ventilators
https://www.yahoo.com/news/not-fancy-works-mississippi-doctor-012120379.html

Share this with handy people or anyone who wants to volunteer! Let's make these!

JACKSON, Miss. — As states across the country beg for ventilators to help patients suffering with respiratory issues from COVID-19, the University of Mississippi Medical Center is building its own makeshift ventilators with supplies found at a hardware store.

Dr. Charles Robertson, a UMMC pediatric anesthesiologist and the mastermind behind the idea, said he set out to make the "absolute simplest ventilator we can build with parts available in any city, you don't need special tools to put together and can be done quickly as the need arises."

Made with "primarily a garden hose, a lamp timer and electronic valve," the ventilator, named the Robertson Ventilator, for less than $100, can be assembled in approximately 20 to 30 minutes, meaning a dedicated team of four to five could produce nearly 100 in a day if needed, he said.

 

[Astronuc]

Maybe the richer people traveled to Europe more?
https://www.nytimes.com/2020/04/08/science/new-york-coronavirus-cases-europe-genomes.html

There is also the suggestion that the Grand Princess cases in California came from Washington
https://www.mercurynews.com/2020/03...eak-gene-detectives-see-link-to-seattle-case/

Of course one needs to be careful with these, as they could be independent introductions (ie. correlation is not causation).

From the cited NY Times article,

Dr. van Bakel and his colleagues found one New York virus that was identical to one of the Washington viruses found by Dr. Bedford and his colleagues. In a separate study, researchers at Yale found another Washington-related virus. Combined, the two studies hint that the Coronavirus has been moving from coast to coast for several weeks.

That would apply to January, February and March.

The Mercury News article echoes similar articles from early to mid-March concerning the similarity of a virus genome from the Placer County individual and one case from Washington state. However, it would seem possible that multiple individuals traveled from Wuhan to SFO as well as SEA, with similar or the same virus. There were dozens of flights between WUH and both SFO and SEA during January, but less so after the travel restrictions at the end of January.

In another NY Times article dated March 1 before the positive cases and fatalities started accelerating,
https://www.nytimes.com/2020/03/01/health/coronavirus-washington-spread.html

The two people live in the same county, but are not known to have had contact with one another, and the second case occurred well after the first would no longer be expected to be contagious. So the genetic findings suggest that the virus has been spreading through other people in the community for close to six weeks, according to one of the scientists who compared the sequences, Trevor Bedford, an associate professor at the Fred Hutchinson Cancer Research Center and the University of Washington.

Dr. Bedford said it was possible that the two cases could be unrelated, and had been introduced separately into the United States. But he said that was unlikely, however, because in both cases the virus contained a genetic variation that appears to be rare — it was found in only two of the 59 samples whose sequences have been shared from China, where the virus originated.

The situation in NY is complicated because the region is served by two international airports, EWR and JFK, both of which receive international passengers from Europe and Asia, as well as domestic flights from across the country, including the West Coast.

Hundreds of thousands of commuters travel through the NY City metropolitan region each day. One commuter could infect dozens of fellow commuters, as was the case of one attorney from New Rochelle who commuted to an office near Grand Central Station in NY City. Tens of thousands commute from Westchester County into NY City. White Plains alone has about 12,000 commuters per day traveling to NY City.

A commuter makes at least two train trips per day. Passenger cars sit 3 on each side of the car, with a similar density to a 737, although the rows are on a greater pitch. One person could infect 5 to 8 people each trip, as well as other commuters on the platforms at both stations. So the R_o value > 3, and seems to be situational.

May 2018 - https://www.businessinsider.com/manhattan-gif-commute-travel-patterns-2018-5

On an average day in New York City, hordes of commuters pour into Manhattan from other boroughs, doubling the island's population from about 1.6 million to 3.1 million.
. . .
As a whole, Manhattan's population swings considerably throughout the workweek. But certain parts of the island have more workers during the day than others: particularly Financial District (FiDi) downtown— the home of Wall Street — and Midtown. At their peaks, FiDi and Midtown increase their overnight populations by about 4 times (to over 250,000 people) and 10 times (to over 680,000 people), respectively.

http://web.mta.info/mnr/html/mnrmap.htm
https://new.mta.info/map/5256

Adding some context to the numbers in NY City Metropolitan area (as of April 8) related to COVID-19.

County       Tested     Tested Pos.  Pop. 2019 est
Kings        45026         23394     2,559,903
Queens       48971         27752     2,253,858
Bronx        34277         17792     1,418,207
Manhattan    29083         12106     1,628,706
Nassau       44097         20140     1,356,924
Westchester  52237         17004       967,506
Suffolk      40253         17413     1,476,601
Richmond     13469          5984       476,143

County       Place        Residence
           of Fatality  of Individual
Kings         1473          1599
Queens        1400          1650
Bronx         1046          1108
Manhattan      985           674
Nassau         778           633
Westchester    389           359
Suffolk        369           362
Richmond       246           249

New York City is comprised of the 5 boroughs (counties) Manhattan, Kings, Queens, Bronx, Staten Island (Richmond County). Westchester County borders on the north of Bronx. Queens borders Nassau, and Suffolk is east of Nassau on Long Island.

 

[peanut]

There are also multiple strains of Coronavirus so while you may have beaten one strain, there's another right around the corner perhaps not a virulent since you've battled its cousin but still something you can get.

https://www.newscientist.com/articl...are-there-two-strains-and-is-one-more-deadly/

Yeah, I have learned there are reportedly 8 strains of SARS-CoV-2 in the world. We need nine lives!

 

[peanut]

Good News: University of Pittsburgh School of Medicine scientists announced a potential vaccine against SARSCoV2, the Coronavirus causing the COVID19 pandemic. When tested in MICE, the vaccine, delivered through a fingertip-sized patch, produces antibodies to neutralize the virus. This is (so far!) the first study to be published after critique from fellow scientists (PEER REVIEW). The researchers are now in the process of applying for an investigational new drug (IND) approval from the US Food and Drug Administration in anticipation of starting a Phase I human clinical trial in the next few months.

https://www.upmc.com/media/news/040220-falo-gambotto-sars-cov2-vaccine

 

[Astronuc]

Grand Princess -

During February 11–21, 2020, the Grand Princess cruise ship sailed roundtrip from San Francisco, California, making four stops in Mexico (voyage A). Most of the 1,111 crew and 68 passengers from voyage A remained on board for a second voyage that departed San Francisco on February 21 (voyage B), with a planned return on March 7 (Table). On March 4, a clinician in California reported two patients with COVID-19 symptoms who had traveled on voyage A, one of whom had positive test results for SARS-CoV-2. CDC notified the cruise line, which began cancelling group activities on voyage B. More than 20 additional cases of COVID-19 among persons who did not travel on voyage B have been identified from Grand Princess voyage A, the majority in California. One death has been reported. On March 5, a response team was transported by helicopter to the ship to collect specimens from 45 passengers and crew with respiratory symptoms for SARS-CoV-2 testing; 21 (46.7%), including two passengers and 19 crew, had positive test results. Passengers and symptomatic crew members were asked to self-quarantine in their cabins, and room service replaced public dining until disembarkation. Following docking in Oakland, California, on March 8, passengers and crew were transferred to land-based sites for a 14-day quarantine period or isolation. Persons requiring medical attention for other conditions or for symptoms consistent with COVID-19 were evaluated, tested for SARS-CoV-2 infection, and hospitalized if indicated. During land-based quarantine in the United States, all persons were offered SARS-CoV-2 testing. As of March 21, of 469 persons with available test results, 78 (16.6%) had positive test results for SARS-CoV-2. Repatriation flights for foreign nationals were organized by several governments in coordination with U.S. federal and California state government agencies. Following disinfection of the vessel according to guidance from CDC’s Vessel Sanitation Program, remaining foreign nationals will complete quarantine on board. The quarantine will be managed by the cruise company, with technical assistance provided by public health experts.

https://www.cdc.gov/mmwr/volumes/69/wr/mm6912e3.htm

 

[kyphysics]

For these new drugs that are being tested, if a patient is sick with confirmed or suspected COVID-19, can they sign some sort of medical waiver that allows them to be a test guinea pig?

If so, do the doctors offer it or would patients have to ask?

 

[anorlunda]

'It's not fancy, but it works': Mississippi doctor uses garden hose, lamp timer and electronic valve to create makeshift ventilators

That's likely to be a bad idea. See this:

 

[jedishrfu]

For these new drugs that are being tested, if a patient is sick with confirmed or suspected COVID-19, can they sign some sort of medical waiver that allows them to be a test guinea pig?

If so, do the doctors offer it or would patients have to ask?

Drug testing is more complicated than that. They try to select people carefully. As an example, you might want to try a cancer drug treatment but because you have a separate pre-existing condition you would be ineligible. The fear is that some drug interactions may occur skewing the results against the new treatment and ruining the study that pharmaceutical is paying for to get FDA approval.

That's why there is now Right-to-try Law to allow folks that are terminally ill to get the experimental treatment.

https://www.cnbc.com/2018/05/30/trump-signs-right-to-try-legislation-on-experimental-medicines.html

 

[mfb]

New Zealand and Australia both report falling numbers of new cases. It is possible to stop this virus early on if the countries act fast enough.

Meanwhile Western Europe (broadly defined) makes progress. Now we'll need long-term strategies that keep infections at a low rate while allowing life to normalize as good as feasible.

Italy's and Spain's numbers are still on a downwards trend but it's a really slow process. At least Italy still increases their testing rate (graphs here, scroll down), so maybe that is one of the reasons. Based on ICU beds the situation is getting significantly better.

Germany sees a small downwards trend in new cases. Deaths are still increasing but at a much lower level overall than most neighbors (per capita). Recoveries match new cases.
Switzerland and Norway seem to have a slow decrease as well.
Austria's numbers are falling faster and they count more recoveries than new cases.

In France the number of occupied ICU beds went down for the first time on Thursday and the number of new confirmed cases stabilized.
The Netherlands stabilized their new case counts and new hospitalizations have been going down for a week now. Denmarks' and Portugal's new case counts look like they stopped increasing, too.

No idea how to interpret Belgium and the UK has an unclear trend as well.
Ireland still goes up?

 

[atyy]

https://www.newscientist.com/articl...are-there-two-strains-and-is-one-more-deadly/

I think we discussed this earlier in the thread (there should be an informative post by @Ygggdrasil somewhere back there), and this finding is likely over-interpreted (ie. there are two "strains", but the data is not strong enough to support the idea that one is more deadly than the other).

 

[Keith_McClary]

Having family elders live with their children instead of living independently in a far-away state would provide more supervision and support during emergencies.

On the other hand:
Italy's Coronavirus crisis was accelerated because young Italians spend more time with elderly relatives and took illness home from the cities to the countryside, Oxford scientists say

 

[atyy]

The COVID-19 vaccine development landscape
Tung Thanh Le, Zacharias Andreadakis, Arun Kumar, Raúl Gómez Román, Stig Tollefsen, Melanie Saville & Stephen Mayhew
Nature Reviews Drug Discovery, 9 April 2020
https://www.nature.com/articles/d41573-020-00073-5

 

[mfb]

Antibody tests are there

At technologyreview.com
German source

In a particularly affected German town of 12,500 people they tested a representative sample of 1000, the results of 500 are in. 14% had antibodies, 2% had the virus, in total 15% had contact with the virus (that suggests 1% had both the virus and antibodies).
Based on this study the town had a case fatality rate of 0.37%. Calculated back that means 7 deaths in ~1900 infections, so don't interpret too much into that number.

They also outline a process by which social distancing can be slowly unwound, especially given hygienic measures, like handwashing, and isolating and tracking the sick. They think if people avoid getting big doses of the virus—which can happen in hospitals or via close contact with someone infected—fewer people will become severely ill, “while at the same time developing immunity” that can help finally end the outbreak.

Edit: Interestingly, this study shows a very low number of antibodies in some recovered patients with weak symptoms.

 

[atyy]

Interesting preprint about the German situation

https://www.medrxiv.org/content/10.1101/2020.04.04.20053637v1
Estimate of the development of the epidemic reproduction number Rt from Coronavirus SARS-CoV-2 case data and implications for political measures based on prognostics
Authors: Sahamoddin Khailaie, Tanmay Mitra, Arnab Bandyopadhyay, Marta Schips, Pietro Mascheroni, Patrizio Vanella, Berit Lange, Sebastian Binder, Michael Meyer-Hermann

Abstract: The novel Coronavirus SARS-CoV-2 (CoV) has induced a world-wide pandemic and subsequent non-pharmaceutical interventions (NPI) in order to control the spreading of the virus. NPIs are considered to be critical in order to at least delay the peak number of infected individuals and to prevent the health care system becoming overwhelmed by the number of patients to treat in hospitals or in intensive care units (ICUs). However, there is also increasing concern that the NPIs in place would increase mortality because of other diseases, increase the frequency of suicide and increase the risk of an economic recession with unforeseeable implications. It is therefore instrumental to evaluate the necessity of NPIs and to monitor the progress of containment of the virus spreading. We used a data-driven estimation of the evolution of the reproduction number for viral spreading in Germany as well as in all its federal states. Based on an extended infection-epidemic model, parameterized with data from the Robert Koch-Institute and, alternatively, with parameters stemming from a fit to the initial phase of CoV spreading in different regions of Italy, we consistently found that the reproduction number was turned down to a range near 1 in all federal states. We used the latest reproduction number as a starting point for the simulation of epidemic progression and varied the reproduction number, mimicking either release or strengthening of NPIs. Germany is currently, April 3rd, 2020, at the border line of a reproduction number between the scenarios of major immunisation of the population or eradication of the virus. We strongly recommend to keep all NPIs in place and suggest to even strengthen the measures in order to accelerate reaching the state of full control, thus, also limiting collateral damage of the NPIs in time.

 

[chemisttree]

Oh really.
https://www.msn.com/en-us/news/us/more-than-930-coronavirus-cases-in-kc-metro-with-3-new-deaths-tied-to-kck-clusters/ar-BB12lIB6:
https://www.kansas.com/news/coronavirus/article241810656.html#adnrb=900000
https://www.kansascity.com/news/coronavirus/article241863906.html

I'll leave the absurdly obvious conclusion to readers.

Just imagine how many cases there would be if they hadn’t prayed away most of the virus.

 

[Ygggdrasil]

There are also multiple strains of Coronavirus so while you may have beaten one strain, there's another right around the corner perhaps not a virulent since you've battled its cousin but still something you can get.

https://www.newscientist.com/articl...are-there-two-strains-and-is-one-more-deadly/

Yeah, I have learned there are reportedly 8 strains of SARS-CoV-2 in the world. We need nine lives!

I think we discussed this earlier in the thread (there should be an informative post by @Ygggdrasil somewhere back there), and this finding is likely over-interpreted (ie. there are two "strains", but the data is not strong enough to support the idea that one is more deadly than the other).

Here is what I have said about the different "strains" of the virus in previous posts:

The paper making the claim about two different strains of the virus has been criticized by other researchers in the field:

An analysis of genetic data from the ongoing COVID-19 outbreak was recently published in the journal National Science Review by Tang et al. (2020) 84. Two of the key claims made by this paper appear to have been reached by misunderstanding and over-interpretation of the SARS-CoV-2 data, with an additional analysis suffering from methodological limitations. [...] Given these flaws, we believe that Tang et al. should retract their paper, as the claims made in it are clearly unfounded and risk spreading dangerous misinformation at a crucial time in the outbreak.

http://virological.org/t/response-to-on-the-origin-and-continuing-evolution-of-sars-cov-2/418

According to the Tang paper, the S and L strains they identify are primarily differentiated by two mutations, one in the orf1ab gene and the other in the ORF8 gene. Neither of these genes are expressed on the surface of the virion, so the mutations will not affect immunity to the virus, and I would expect immunity to one "strain" to confer immunity to the other "strain." The spike protein is the main protein on the surface of the virus, so scientists should monitor mutations in the spike protein to find potential mutations that could affect immunity against the virus.

Regarding the eight "strains" of the virus, the fact that we observe different genotypes because the virus has accrued various mutations, does not mean that these different "strains" of the virus are capable of re-infecting individuals. As an analogy, human individuals differ by ~20 million base pairs, but (as far as we know) all are equally susceptible to the Coronavirus (so to the virus, there is only one strain of human). Only very specific mutations could allow a human to be immune from the virus (e.g. in the case of HIV), and likewise, only very specific mutations in the SARS-CoV-2 virus would allow it to evade immunity in vaccinated individuals.

Thus, many mutations will not have any effect on the virus, and we would mainly care about mutations that affect the behavior of the virus. So far, we have not seem much meaningful change to the viral genome, and the various mutations that differentiate the "strains" (while useful for tracking the spread of the virus) are not expected to affect our immunity to the virus:

Since the start of the pandemic, the virus hasn’t changed in any obviously important ways. It’s mutating in the way that all viruses do. But of the 100-plus mutations that have been documented, none has risen to dominance, which suggests that none is especially important. “The virus has been remarkably stable given how much transmission we’ve seen,” says Lisa Gralinski of the University of North Carolina. “That makes sense, because there’s no evolutionary pressure on the virus to transmit better. It’s doing a great job of spreading around the world right now.”

There’s one possible exception. A few SARS-CoV-2 viruses that were isolated from Singaporean COVID-19 patients are missing a stretch of genes that also disappeared from SARS-classic during the late stages of its epidemic. This change was thought to make the original virus less virulent, but it’s far too early to know whether the same applies to the new one.

https://www.theatlantic.com/science/archive/2020/03/biography-new-coronavirus/608338/
(note: this article from the Atlantic is a great, popular press summary of what we know about how the virus differs from other coronaviruses, and how those differences may lead to its success in spreading across the globe).

Now, that is not to say that the virus won't or cannot mutate to evade immunity. These types of mutations are certainly possible, and people are monitoring virus sequences to monitor for that possibility. Because the immune system recognizes the protein on the surface of the virus (the spike protein), it is very important to monitor changes to the spike protein as these types of mutations do carry the possibility of altering how our immune system recognizes the virus.

A greater concern is some of the research mentioned by @mfb suggesting that some fraction of people with mild COVID-19 infections have very low levels of antibodies against the virus after recovery.

 

[kyphysics]

That's likely to be a bad idea. See this:

someone needs to get this info. to that doctor then

 

[kyphysics]

Edit: Interestingly, this study shows a very low number of antibodies in some recovered patients with weak symptoms.

a.) SOME antibodies are better than none, though, right?
b.) Would that mean you'd need to recover from a severe case of COVID-19 to get LOTS of antibodies?
c.) If you recovered from a weak case and have few antibodies, does that mean you'd not necessarily be able to fight off the virus again if exposed?

I know we're still early in data collection/analysis and any answers may just be preliminary or speculative, but still asking anyways.

 

[atyy]

a.) SOME antibodies are better than none, though, right?
b.) Would that mean you'd need to recover from a severe case of COVID-19 to get LOTS of antibodies?
c.) If you recovered from a weak case and have few antibodies, does that mean you'd not necessarily be able to fight off the virus again if exposed?

I'm not sure, but the post-recovery antibody level has also been discussed in the context of using convalescent plasma for treatment, where it makes sense that one would need high antibody levels. Interestingly, this review says that in other diseases, there may be non-neutralizing antibodies that contributed to recovery.

"The latter study highlights a challenge in using convalescent sera, namely, that some who recover from viral disease may not have high titers of neutralizing antibody (23). Consistent with this point, an analysis of 99 samples of convalescent sera from patients with SARS showed that 87 had neutralizing antibody, with a geometric mean titer of 1:61 (3). This suggests that antibody declines with time and/or that few patients make high-titer responses. It is also possible that non-neutralizing antibodies are produced that contribute to protection and recovery, as described for other viral diseases (24–26)."

 

[Keith_McClary]

Flow analyses to validate SARS-CoV-2 protective masks
About distance rules, mouth-nose protection, particle filtering respiratory protection, filter materials and mask manufacturing

Christian J. Kähler, Rainer Hain University of the Bundeswehr Munich Institute of Fluid Mechanics and Aerodynamics Werner-Heisenberg-Weg 39 85577 Neubiberg Germany