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# March 29

## UV light and the coronavirus

There are medical devices that use UV light to "kill" viruses. I have two novelty 75 watt Blacklight incandescent bulbs of the type that are sold in Halloween superstores. I was thinking of rigging up a lightbox lined with aluminum foil and putting things like car keys, credit cards, work gloves, facemasks and the like into it. I would ventilate the box because these bulbs run hot. My son who is a geek says these bulbs emit UVA and what I need is UVC LEDs. He seems to be saying politely that this project is a waste of time, and I concede that he is probably right. Can I get a second opinion? At least I can make Velvet Elvis paintings glow. Cullen328 Let's discuss it

I'm not going to make any claims about what wavelengths of ultraviolet light kill this virus, but in general party blacklights are UVA whereas germicidal lamps are UVC. But if you have enough Velvet Elvis paintings whose glow can be seen from afar, nobody will get within 6 miles feet of you and you won't get infected. DMacks (talk) 04:35, 29 March 2020 (UTC)
UVC LED's are nowhere near powerful enough to sterilize stuff. Germicidal UV lamps are fluorescent and you have to wear safety goggles and stuff when using them. As for actually sterilizing stuff like masks, that is edging towards medical advice and all I can say is better check some good scientific or medical references about UV sterilization. This is about UV germicidal irradiation (UVGI) but I haven't read it. There is also starting to be a literature about sterilizing facemasks using an oven,[1] steam from boiiling water etc. General recommendations I've seen for credit cards, mobile phones etc. are to wipe them down with spray cleaner. 2601:648:8202:96B0:E0CB:579B:1F5:84ED (talk) 09:34, 29 March 2020 (UTC)
There are UVC LEDs intended for sterilization now. But yes, most germicidal lamps have historically used a fluorescent design. DNA has a specific UV absorption band ~260 nm (in the UVC), which is what makes germicidal UV so effective. At the same intensity, UVA absorption is less than 1/1000th of the effect of UVC. Dragons flight (talk) 11:20, 29 March 2020 (UTC)
• UVC LEDs have been a thing for a while now.[2] They could become an important means of improving water sterilisation for small-scale, low-power, such as solar-powered units. There are still questions out there on their longevity, and such applications should really have built-in testing for light output. But they're certainly viable as UVC sources, and as replacements for fluorescents. They avoid the mercury too. Andy Dingley (talk) 20:32, 29 March 2020 (UTC)
Novelty blacklights usually are coated with phosphor to produce a purple light while also allowing some UV to escape. Fluorescent lamps used for sterilization have a clear tube with no phosphor, to allow UV to escape unimpeded. Remember, most humans can't see UV; if you can see a lamp giving off light, that tells you at least some of what it's giving off is visible light. Side topic: all "white" fluorescents are mercury lamps, which are the same kind used in blacklights and germicidal lamps. Fluorescence is a quantum mechanical phenomenon; electrons become excited and emit photons to become un-excited. The wavelengths of the emitted photons are very specific and depend on the electronic properties of the material. Mercury is used because it has a low vapor pressure (it can be a gas at room temperature) and fluoresces in UV. The resulting UV photons can be absorbed by phosphor molecules, which themselves become excited and re-emit photons at longer wavelengths; for "white" lamps, a mixture of phosphors is chosen that produces visible light. Also note that UV is good at promoting lots of photochemical reactions. A lot of plastics will degrade when exposed to UV light. Plastic items intended for outdoor use have UV stabilizers added to inhibit this, if needed (not all plastics react to UV). --47.146.63.87 (talk) 01:56, 30 March 2020 (UTC)

### UVC vs UVA lamps

Just to expand on "Novelty blacklights usually are coated with phosphor to produce a purple light while also allowing some UV to escape. Fluorescent lamps used for sterilization have a clear tube with no phosphor, to allow UV to escape unimpeded.". the phosphor actually puts out quite a bit of blue along with UVA and looks bluish white. These bulbs are often used in bug zappers. The ones used to make your dogs playing poker velvet painting fluoresce also have colored glass that mostly filters out everything except UVA and a bit of deep violet. The UVC tubes are made of quartz, because glass blocks most UVC.

At a trendy hip-hop fashion event in Hong Kong, attendees experienced sunburn and eye problems after the lighting contractor used UVC bulbs instead of UVA.[3][4] --Guy Macon (talk) 04:26, 30 March 2020 (UTC)

Commodity glass is also quartz, although it often has impurities and additives. Germicidal lamps usually use fused quartz which as you note transmits UV better. --47.146.63.87 (talk) 06:21, 31 March 2020 (UTC)

Whether you use leds or fluorescent tubes be very careful about eye exposure and somewhat careful of skin exposure. 2601:648:8202:96B0:E0CB:579B:1F5:84ED (talk) 08:23, 30 March 2020 (UTC)

## Are there protein vitamins?

I've told two different opinions about vitamins: one opinion (biological science student) says that there are vitamins made of proteins. Second opinion (a PhD from Bristol university) says it can't be because if they were they’d be broken down into amino-acid units during digestion by proteases rather than absorbed. Now, according to the article here (vitamin) there is one vitamin (U) which is protein metabolize. So as far as I understand the student is wrong. Am I correct? 93.126.116.89 (talk) 20:07, 29 March 2020 (UTC)

S-Methylmethionine is a single amino acid, not a protein. There is a cited statemnt in that article "S-Methylmethionine is sometimes referred to as vitamin U,[3] but it is not considered a true vitamin." DMacks (talk) 20:19, 29 March 2020 (UTC)
The article says it is a protein metabolite, not a protein metabolize. A metabolite is a molecule that results from breaking up larger molecules, in this case proteins. So a protein gets broken up into amino acids, one of which is methionine. This then gets modified (by methylation, that is, a methyl group is added to the molecule) and becomes S-methylmethionine, aka vitamin U. The PhD was right in this case.  --Lambiam 21:33, 29 March 2020 (UTC)
You'll note that "vitamin U" is listed as a reclassified vitamin: something that some people considered at one time to be a vitamin, but is not generally considered one at present. The modern definition of "vitamin" is an essential micronutrient that isn't a mineral. SMM is not a vitamin, as it's not essential; the body produces it from other chemicals, and this production appears adequate for its needs. It is correct that proteins and peptides are generally digested if consumed orally. This is why we can't administer insulin, a peptide hormone, orally. There is some interesting research suggesting some peptides are resistant to digestion and might be a viable route for drug administration, but that's a different topic. Some amino acids are essential nutrients, but they're not considered vitamins because they're macronutrients. Generally you ingest them in proteins, which are digested into their component amino acids. --47.146.63.87 (talk) 01:37, 30 March 2020 (UTC)

# March 30

## Indigenous Australians and COVID-19

Two days ago, Australian PM Scott Morrison announced new restrictions on gatherings (in particular, no more than two people together unless they're part of the same household), and urged certain vulnerable populations to be particularly careful about going out. People aged 70+, to be expected. People aged 60+ with a chronic illness, expected. Indigenous people over the age of 50. Why? What makes them more vulnerable than other people over the age of 50? Has some sort of genetic vulnerability been observed?

Nyttend (talk) 11:39, 30 March 2020 (UTC)

"Aboriginal and Torres Strait Islander people, who have higher rates of chronic illness" Groups at higher risk of developing COVID-19 - Australian Government Department of Health. Alansplodge (talk) 11:53, 30 March 2020 (UTC)
"Chronic conditions like respiratory diseases (including asthma), heart and circulatory diseases, high blood pressure, diabetes, kidney diseases and some cancers are more common among Aboriginal and Torres Strait Islander people than among non-Indigenous people in WA. These conditions tend to occur at younger ages for Aboriginal and Torres Strait Islander people than non-Indigenous people". Chronic Diseases - Australian Indigenous HealthInfoNet Alansplodge (talk) 11:57, 30 March 2020 (UTC)
(edit conflict) Diabetes and renal failure are more prevalent; much higher smoking rates; limited if any medical care facilities; remote locations. [5] Bazza (talk) 12:00, 30 March 2020 (UTC)
More information at Indigenous coronavirus taskforce meets as remote communities restrict access. Alansplodge (talk) 12:07, 30 March 2020 (UTC)
Remote communities have a chance of staying virus free for longer with travel restrictions and other precautionary measures. Aboriginal people are more likely than non-Aboriginal people to live in remote communities. Also, the cost of managing severe health problems in remote communities is significantly more per person than in urban areas, and the availability of health services and the government's capacity to deal with serious cases in remote areas is significantly lower. Also, Aboriginal health on average is far worse than that of non-Aboriginal people. Aboriginal and non-Aboriginal health statistics are presented in the Closing the Gap report - https://ctgreport.niaa.gov.au/ MathewMunro (talk) 12:59, 30 March 2020 (UTC)

## Wuhan's seasonal rate of all-cause mortality

I've spent a long time trying to find the usual average monthly death rate (due to all causes) in Wuhan.
I am looking for the all-cause mortality rate per month/quarter (etc).
Does anyone know where I can find this data?
Please note: I am not searching for the COVID-19 mortality data.
If someone could point me to this data I would be forever indebted.
Thank you,
Vitreology talk 22:34, 30 March 2020 (UTC)

Wuhan COVID-19 Death Toll May Be in Tens of Thousands, Data on Cremations and Shipments of Urns Suggest (2020-03-29; Christina Zhao; Newsweek) quotes some numbers they got from the Chinese language Wuhan government 2019Q4 Wuhan Civil Affairs Statistics page, which includes links to the 2018Q1 -- 2019Q3 pages. Drop that link into a translator and see if those pages give you what you want. "Number of cremated remains" (near the bottom) is presumably equivalent to deaths. -- ToE 04:58, 31 March 2020 (UTC)
List_of_countries_by_cremation_rate#China says the cremation rate is about 50% for China, so number of cremation ≠ number of deaths. (I have no idea whether said rate is higher or lower in Wuhan than in the rest of the country.) TigraanClick here to contact me 09:02, 31 March 2020 (UTC)
It could be that China has decided to cremate all the deceased just in case. Or that this is an "I drunk 50 bottles of beer" exaggeration that passed too many people in a Chinese whispers game before landing in a tabloid of note. 89.172.106.70 (talk) 10:09, 31 March 2020 (UTC)
Thanks Tigraan. So that is just a list for civil services rendered. Presumably there are birth/death statistics out there somewhere. -- ToE 12:03, 31 March 2020 (UTC)
Thinking of England Tigraan, Thank you both for all your input so far.
I'm speaking with a chap living in Wuhan at the moment and it appears that the gov is forcing all bodies to be cremated, with significant fines being issued for non compliance with this.
Sale of urns could be a reasonable proxy for mortality rate.
Family either bury the earn in a cemetery where there's a tombstone positioned in the ground above the urn. Alternatively, the urn is placed in a cabinet, either within the cemetery or in the temple. Apparently, the cost of the urn burial sites / cabinets has become extremely expensive, so many are resorting to simply burning the urn (I assume the urn is made from wood). Irrespective of what happens to the urn, everyone gets a tombstone unless they are homeless or have no family/friends. Changes in the appearance of cemeteries (via satellite imagery: Historical images in Google Earth etc) could be used as a proxy for mortality rate.
Birth/death rate in specific Chinese provinces is very difficult to find.
Apparently there are two festivals (Qingming and Zhongyuan) where families mourn the dead, and burn "ghostcash". The dates of the festivals are determined by the Chinese traditional lunar calendar, but I believe Qingming is 4th of April this year. It will be very interesting to see what happens here - whether gatherings are permitted. Perhaps the world will gain a more accurate insight into the amount of people who have died in the past 6-12 months, based on the attendance numbers at this festival. There doesn't appear to be any sort of online registration system for these festivals which could be used as a proxy for mortality rate.
That's my research into this so far. I'd be grateful for any info anyone can provide to get closer to working out what the mortality rate in Wuhan is. PS: part of the reason I'm seeking this info is to work out if (or to what extent) the rates of death from non-infectious causes (heart attacks etc) rise during a pandemic like this. Kind regards, Vitreology talk 12:41, 31 March 2020 (UTC)
In case there's some confusion, Qingming Festival is not simply a time to honour those who have recently died. It's for all ancestors. Likewise ghost money/joss paper and such ghost items and offerings are generally burnt at the funeral, during Qing Ming, and also other times. At least that's how it among Chinese Malaysians, but from our articles and other sources I don't think it's that different in China.
Also although it may be called a "festival", I don't think it makes much sense to talk about 'attendance', let alone online registration. It's possible there may be some minor public events, but the primary ones are private particularly visiting ancestors tombs, cleaning them, making offering and praying. (By private I mean involving the family, obviously if lots of families are visiting cemeteries, there's likely to be quite a lot of people in the same area but each family is mostly doing their own thing.) [6] [7] It's possible that people may be stronger in their observances if someone has recently died, but I'm not so sure.
Of course the current situation especially in Wuhan is a bit unusual since the lock down is only now being lifted so it's likely people have not been able to properly perform Chinese funeral rituals, still, I'm unconvinced they're going to combine them with what they do on Qingming. Frankly if you wanted a proxy, I wonder if counting how many people are wearing red over the next few weeks might be your best bet but even then, probably not.
BTW, as an aside, the article on funeral rituals suggestions cremation tends to be higher in the cities. So even if the government wasn't dealing with the various current problems in the obvious way by requiring cremation, the 45% may not apply to Wuhan anyway.
Nil Einne (talk) 14:33, 31 March 2020 (UTC)
Nil Einne Very helpful insights, thank you.
Would you happen to know where I can find the overall mortality rate in Wuhan, per year? Vitreology talk 14:44, 31 March 2020 (UTC)
I saw that report about Wuhan and something similar about Italy.[8] I don't know what to make of it. 2601:648:8202:96B0:E0CB:579B:1F5:84ED (talk) 06:44, 31 March 2020 (UTC)
Probably nothing much. There's a huge amount of fake news circulating about Italy. At some point we'll know but it's far, far too early to tell, especially in the current political trolling climate. 89.172.106.70 (talk) 10:09, 31 March 2020 (UTC)
That's based on statistical analysis of reported deaths vs. ordinary population death rate. The thing is, if the healthcare system is overwhelmed, some people will die otherwise possibly preventable deaths. If you have a heart attack but the nearest hospital is overflowing with COVID-19 patients and can't treat you, you might die when with treatment you wouldn't. But the question is, do you count that as part of the "COVID-19 death toll"? --47.146.63.87 (talk) 18:57, 31 March 2020 (UTC)
Spot on. You have perfectly summarised the reason I'm asking this question.
Vitreology talk 00:33, 1 April 2020 (UTC)

# March 31

## intriguing experiment in Thermodynamics

A blech is destined for preserving the heat of cooked food during Shabbat, in accordance with jewish religious law. In an experiment performed is Jerusalem. a small towel has been put on on one blech, and an identical one on another blech, which was covered by an Aluminium foil before. The resulting temperatures were different significantly - so much so, that the 2nd towel has been scortched, and even a light wind coming from an open window caused the burst of a flame. Surely, there must a reason to this temperature difference, even though it's 'only' a thin metallic coat over a metallic plate that makes the difference. I'll glad to hear your opinion or hypothesis regarding this phenomenon. בנצי (talk) 22:36, 31 March 2020 (UTC)

Just to clarify, it was the blech that was covered by foil in the second case, not the towel itself? And it was just a thin layer of foil that did not extend beyond the blech itself (to change the overall surface area or air circulation)? DMacks (talk) 03:28, 1 April 2020 (UTC)
• The "obvious" thing (well, obvious for someone with a PhD in the domain, I guess) would be a difference in thermal radiation. I highly recommend reading the lede of our article emissivity, which is IMO really well-written.
Qualitatively, aluminium foil emits a low amount of radiation (our article says emissivity is 3%; unsourced but seems plausible to me), and hence cools down more slowly. More precisely, if you assume the whole burner-blech-foil system reaches a steady state, the outbound heat flux must compensate the heat of combustion of the burner; to have the same outbound radiative heat flux, a lower-emissivity surface will need to be hotter.
Quantitatively, if we assume that the loss of heat by convection is negligible (dubious, but will do as a first-approximation), and that the emissivity does not depend much on temperature in the relevant range (source: trust me, or look for emission spectra and do nasty integrals weighted by Planck's law at temperatures between ambient and 500°C; the materials we are dealing with are grey bodies in the relevant ranges), we have a similar outbound heat flux in both situations when ${\displaystyle \epsilon _{foil}T_{foil}^{4}=\epsilon _{unfoiled}T_{unfoiled}^{4}}$ (see Stefan-Boltzmann law, where absolute temperatures (i.e. in Kelvin) are used; the constant σ cancels out in both sides). Assuming ${\displaystyle \epsilon _{foil}=0.03}$ (from Emissivity#Emissivities_of_common_surfaces), ${\displaystyle \epsilon _{unfoiled}=0.9}$ (a fairly typical value for most ceramics, non-metal construction materials etc. - impossible to be precise without knowing the exact material of the blech), and ${\displaystyle T_{unfoiled}=70^{\circ }C\approx 350K}$ (might be off by 20°C or more but it would not change much), one finds ${\displaystyle T_{foiled}\approx 820K\approx 540^{\circ }C}$ which is extremely hot. That is due to a very high ratio ${\displaystyle \epsilon _{unfoiled}/\epsilon _{foil}}$ of about 30 ; if we take 10 instead (for instance ${\displaystyle \epsilon _{unfoiled}=0.8}$, ${\displaystyle \epsilon _{foil}=0.08}$, in the realm of the plausible) we get 350°C, still very hot.
I opine that the more plausible "obvious" explanation is that there is some kind of misreporting about how perfectly scientifically this so-called control-experiment demonstrates the desired result. Whether this is a case of honestly-naïve observer bias or outright religiously-motivated fraudulent pseudoscience - perhaps I might be so bold as to lob an accusation that no such experiment was even performed! - the probable explanation is that there is no such effect: the natural laws that govern thermal behaviors are statistically unlikely to take a day of rest to respectfully honor any particular human notion of piety. Regarding the so-called experiment ... may I rhetorically entreat "citation needed"? I'm not so interested in actually reading about it - more so, I'm just encouraging our readers to consider whether they should ever put stock on anecdotal reports about miraculous occurrences, religious or otherwise. Science is built on a foundation of healthy philosophical skepticism; most of the time, the simple explanation doesn't need much detailed analysis beyond a broad recognizance of the generally-faulty ability of humans to report the things that they think they know to be truth. Nimur (talk) 12:32, 1 April 2020 (UTC)
@Nimur: I do not see the OP making any religious interpretation of their claimed observations (they do say in Jerusalem and presumably it was on a day of Shabbat, but I doubt they think the result would be different on another day or in another place). They claim the "experiment" was well-controlled or novel either; I would presume that "experiment" was intended as a colloquial term. Finally, I see no indication that the OP is a refdesk troll that should not be fed.
Regardless of whether the OP did indeed make the observations they claim, the numbers I plugged suggest that an aluminium-foiled blech can indeed go very hot (be it used on Shabbat or any other day). I would even go so far as to say that if the question had been "should I cover a blech with aluminium foil for (whatever reason)", I would have made the same calculations and warned against the danger of so doing because of thermal considerations. If you think the calculation result is erroneous by a large margin, please point out the error either in the reasoning or in the initial assumptions.
By the way, I think the whole Shabbat interdicts are inane nonsense, between "the Torah says no fire, so no electricity either because electricity is fire" and "actually fire/electricity is OK but only if you do not touch the controls". That mention should have no impact either way on the credibility of my calculations, but it might cut short some drama. TigraanClick here to contact me 13:38, 2 April 2020 (UTC)
For an overview of the positions and arguments, see Electricity on Shabbat.  --Lambiam 08:22, 4 April 2020 (UTC)

# April 1

## Medical terminology question

What is the technical term for that gross stuff that comes out of one's nose when one has the flu? Freeknowledgecreator (talk) 08:05, 1 April 2020 (UTC)

nasal mucosa-gadfium 08:19, 1 April 2020 (UTC)
Gadfium, I'm sorry but this is incorrect. The correct term is nasal discharge, mucosal discharge, or phlegm. The term sputum cannot be used when it applies to the nasal cavity, whereas the terms phlegm and mucosal discharge may be used when it is located anywhere within the respiratory tract. Cheers, Vitreology talk 10:07, 1 April 2020 (UTC)
Or nasal mucus. Hopefully your nasal mucosa remains attached to the rest of your body, or else your ailment is much graver than the flu.  --Lambiam 10:44, 1 April 2020 (UTC)
Lambiam: Absolutely correct. The nasal mucosa makes a secretion called mucous. There are a number of blistering conditions where the nasal mucosa may theoretically discharge (rare). Vitreology talk 11:18, 1 April 2020 (UTC)
Mucus, not mucous. Only adjectives end in ous. 93.142.71.7 (talk) 11:15, 2 April 2020 (UTC)
In light of the qualified nature of the original question, I think the medically-accurate term would be "influenza associated nasal discharge"; or even - dare I say - "influenza-like illness associated nasal discharge", following the terminology guidance from CDC's Glossary of Influenza (Flu) Terms. The fine staff at CDC, including career medical researchers, strongly caution against prematurely attributing symptoms to any specific causative agent.
Nimur (talk) 12:51, 1 April 2020 (UTC)
The tests may more important to epidemiologists who are trying to stop the pandemic from spreading, than to clinicians who are trying to treat patients who are already sick. Both are important. 2601:640:105:1E35:C074:F68C:EEC6:9F48 (talk) 08:05, 4 April 2020 (UTC)

## What are these engine parts? (Pictures included)

I was walking in a remote woodland and I found a rusty vehicle interior of some kind. Can anyone identify what this is and it's purpose?

--Polegåarden (talk) 19:23, 1 April 2020 (UTC)

Maybe it's an Overhead camshaft engine, judging by the stylized "OHC" stamped on top. Bus stop (talk) 19:30, 1 April 2020 (UTC)
It’s an Opel (compare [9]). According to Google, the exhaust manifold part no. 90 108 040 was apparently used in the Corsa A and Kadett D, among others. Cheers  hugarheimur 20:44, 1 April 2020 (UTC)
So then the engine is indeed an overhead camshaft engine. According to our Opel Kadett article, an Opel OHC engine was used in some models of the Opel Kadett D produced in South Africa.  --Lambiam 07:16, 2 April 2020 (UTC)
Not just in South Africa – the same engines were also used in German-made Opels. I think it’s a Family I engine, but I’m not an expert. Cheers  hugarheimur 19:59, 2 April 2020 (UTC)
If you have a reliable source for that, we can adjust the Opel Kadett article accordingly.  --Lambiam 06:52, 3 April 2020 (UTC)
@Polegåarden, I wonder if you could say where this debris is to assist with categorising the images. Many thanks. Richard Avery (talk) 07:15, 3 April 2020 (UTC)
Polegåarden's other uploads have all been in Sussex: File:Holly leaves, Upper Rapeland Wood.jpg near Horsham, File:Graylands, Horsham.jpg near Horsham, and File:Unnamed field inbetween Upper Rapeland Wood and Lower Rapeland Plantation, Old Holbrook. March 2020.jpg near Old Holbrook. Since most of them were taken within a few days of each other, we have good reason to believe that these images, as well, were taken in Sussex. Nyttend (talk) 12:29, 4 April 2020 (UTC)
In that case, it would be a Vauxhall Astra (a re-badged right-hand-drive version of the Kadett). Also note that it is a trasverse-mount engine; and the location of the cam drive confirms that it indeed has an overhead cam. 2606:A000:1126:28D:2D2C:2116:A139:E8FD (talk) 17:45, 4 April 2020 (UTC)

# April 2

## Why developed countries have more deaths due to Coronavirus

Egypt has international passengers, Kenya, Nigeria, Mexico all have airports.

Iran has more deaths than Iraq, even though Iraq has seen more war, terrorism.

Why Iran has more deaths than Saudi Arabia?

South America countries also have low casualty?

Is it due to weather or urban people eat too much junk food, processed food, packaged food instead of purchasing fresh vegetables, meat and cook at home like villagers? — Preceding unsigned comment added by Asafa2004 (talkcontribs) 02:16, 2 April 2020 (UTC)

I have seen it suggested that if you die in Italy or Spain you are tested for COVID19 virus, and if you've got it you count as a COVID19 victim, even if that isn't what killed you. I wonder how many dead people in 3rd world countries get tested? Greglocock (talk) 05:13, 2 April 2020 (UTC)
"what killed you". In most cases a covid19 patient with an existing heart or respiratory condition is admitted to hospital with a fever, develops a secondary infection, and later dies. There are plausibly at least three causes of death, but it stands to reason for nearly all of them that they would not have died at that time if not for covid19. The errors in the other direction can be even worse - people who die from covid19 but were never tested are not listed as having died from it. It's been noticed that the worst-hit areas of Italy have seen the overall death rate more than double even after excluding known covid19 deaths. Someguy1221 (talk) 12:01, 3 April 2020 (UTC)
It's too early to make any judgments about what the real death toll is or will be in various countries. ←Baseball Bugs What's up, Doc? carrots→ 06:29, 2 April 2020 (UTC)
I am not sure that, for example, in Egypt all cases and death are properly counted. However I know that in Egypt already two army generals died of covid-19. So, the infection must widespread enough. Ruslik_Zero 08:50, 2 April 2020 (UTC)
I've read that the virus loses transmission effectiveness around 8-10C dewpoints. If that's true, the tropical zone should be less affected. 93.142.71.7 (talk) 11:13, 2 April 2020 (UTC)
Who's saying that? ←Baseball Bugs What's up, Doc? carrots→ 11:32, 2 April 2020 (UTC)
• The OP contains many dubious premises in the suggested argument for a diet effect.
As said above, the death rate would need to be evaluated at the end of the pandemic, which is in progress. Developed countries will generally speaking get epidemics sooner: more urban (so faster in-country propagation) and more international travelers (so faster to get an imported case). For instance the Black Plague broke in Western Europe via trade routes and in big cities first.
It should also be corrected by the attack rate. SARS killed mostly South-East Asians: it is not because the virus affected collectivism-oriented persons more but because it broke out in South-East Asia and was mostly contained, so a much bigger fraction of the population was infected here.
The case fatality rate is also highly dependent on age for COVID-19, and developed countries have generally speaking older populations. (Which, by the way, proves life in those countries is more generally healthy, health systems better etc.).
Finally, inhabitants of "undeveloped countries" do not all (nor almost all) "purchase fresh vegetables, meat and cook at home like villagers". See for instance Obesity in the Middle East and North Africa, Obesity_in_Mexico, etc. The idea of Third World countries as a homogeneous blob of uncivilized starving hand-to-mouth farmers (the colonialist phrasing) or a pastoral paradise where man is in harmony with nature (the hippie phrasing) has not been true for at least fifty years. That is not to say there aren't areas of subsistence agriculture in today's world; there are "shitholes" (for instance near the African Great Lakes), but not as much as a US president an uninformed person would guess. TigraanClick here to contact me 13:07, 2 April 2020 (UTC)
Even that's an incorrect assumption based on old information, for example Rwanda has been undergoing massive modernization, and is often held up as an example of how our existing impressions of the economics of developing countries is often sorely outdated. Paul Kagame is a rightly controversial figure, and one should not downplay his many problems, but Rwanda has rapidly modernized under his leadership. See here for a UN article about it. There are some real concerns about the problems associated with this rapid growth (see here for an article about that). --Jayron32 13:34, 2 April 2020 (UTC)
I'd also note that "developing countries" covers countries with very different levels of development. A lot of developing countries actually have quite a few urban areas with significantly higher population densities than is common in many developed ones. Just because there is a greater percentage of their population living in rural areas doesn't mean they don't have a lot of people living in dense environments. I'd also note that most Severe acute respiratory syndrome cases were in China, Hong Kong and Taiwan. While South China was the part of China most affected, these 3 are often not considered part of South East Asia. The only SEA country with a reasonable number of cases was Singapore, and they actually had fewer recognised than Canada. Even Taiwan is not really that high, only about 100 or 40% more than Canada and yet if you add the other SEA countries all up, I think you still get fewer than Taiwan. Nil Einne (talk) 07:52, 3 April 2020 (UTC)

## Viruses and bacteria question.

Viruses are generally more dangerous if you breathe it in, than to eat it. After all, if you eat it, it can be destroyed in the liver. Are there any viruses that are more dangerous, to eat it, than to breathe it in? And how about for bacteria? For E. coli, is it like 10-15 pieces of E. coli on a steak is enough to make you sick, so, what about if you were to breathe in that same amount of E. coli? Thanks. 67.175.224.138 (talk) 07:32, 2 April 2020 (UTC).

"Destroyed in the liver"? ←Baseball Bugs What's up, Doc? carrots→ 08:38, 2 April 2020 (UTC)
You are very mistaken. Many viruses have food and eating as a primary means of transmission. This article gives you an overview, specifically noting Hepatitis A. Other common viruses which get in your body primarily from eating include norovirus and rotavirus. Norovirus is one of the most common infections in a year, something close to 8-10% of the world gets it annually. While it is true that certain viruses are spread primarily by air, such as influenza (flu), rhinovirus (common cold), and of course coronavirus, those are viruses that cause respiratory infections. Viruses affect a number of different body systems, and there are (as I note above) a number of digestive viruses which need to be eaten to enter your body. --Jayron32 12:59, 2 April 2020 (UTC)
Well put. An interesting wrinkle is that norovirus can also use a kind of hybrid attack where it becomes aerosolized during the intense vomiting it induces, allowing it to be transmitted via the air. Gross stuff. But even though it may attack via the nose, it's not a respiratory infection. Matt Deres (talk) 14:17, 2 April 2020 (UTC)
I happened to have gotten rotavirus and norovirus, not from eating it, but by breathing it in the air. And gotten gastroenteritis from that. I do wonder what would have been different had I instead, eaten it in. 67.175.224.138 (talk) 16:53, 2 April 2020 (UTC).
That's generally true for all such virus of both types (digestive and respiratory) because the digestive and respiratory systems are basically interconnected, any respiratory virus can enter your system via food, and aerosolized digestive viruses can enter your system via breathing them in. Since basically your mucus and saliva provide access to both systems, the virus's have a non-zero chance of being transmitted via alternate means as you describe, even if that is not the primary means of transmission. Also, if I'm not mistaken, many respiratory viruses are very frequently transmitted via surface transfer; things like handshakes and kisses, rather than just being ambiently "in the air" to be breathed in. Influenza#Transmission has a pretty good break-down of the three modes of transmission (fluid-to-fluid contact, aerosolized particles, and surface contact) and while Covid-19 is a different virus, it is likely to have similar modes. Since food is something we come into contact with regularly, it seems possible and even likely that some transfer of respiratory disease does come from food. --Jayron32 16:59, 2 April 2020 (UTC)
As some have stated, I'm afraid your premise is mistaken. Pathogens tend to specialize in different infection routes. There is no general rule even for human pathogens that one type of pathogen is "more dangerous" through one route. If you breathe in HIV, as long as your respiratory mucosa is intact (no tiny cuts or abrasions that can allow it to enter your blood) it will do nothing. (I'm not even sure if it can viably exist in the air, but this is just for illustration.) And the same is true if you swallow it. E. coli isn't a respiratory pathogen either. There is some potential issue there where mucus lining the respiratory tract mostly winds up being swallowed, but again I'm not sure E. coli can become an aerosol. Also, about E. coli: most strains of it are harmless or even beneficial members of the human gut flora. Only a few strains are human pathogens. Yet another thing: ingested pathogens are usually kept harmless by things like stomach acid, digestive enzymes, competition from the gut flora, and the physical barriers of the digestive tract. Successful gastrointestinal pathogens have to avoid, resist, and/or neutralize these. Instructive examples: H. pylori burrows into the stomach wall; poliovirus resists digestion and then infects gut lymphoid tissue; C. difficile usually only affects people with altered gut environments, like from antibiotic treatment, which kills competing bacteria and allows it to run rampant. The liver usually isn't relevant. Hepatitis A is actually ingested and then targets the liver as its focus of infection! ("Hepatitis" means inflammation of the liver; that's why it got the name.) --47.146.63.87 (talk) 22:00, 2 April 2020 (UTC)
Since we're on a roll for stingy medical terminology pedantry, it's probably worth emphasizing that hepatitis is a disease: "a particular abnormal condition"; hepatovirus is a general name for one or more species of virus in the hepatovirus genus; one of the most commonly-known species is named Hepatovirus A; although if you've been tuning in to the commentary by the International Committee on Taxonomy of Viruses (one of the most prominent virus taxonomy advocacy groups, and recently a real pain in the stickler for accurate viral taxonomy terminology), one of the most pressing problems in the world today is that even scientists can't keep their virus terminology straight.
Nimur (talk) 22:12, 2 April 2020 (UTC)
Yes, thanks for noting that. :) I should properly have said "the hepatitis A virus". --47.146.63.87 (talk) 02:37, 4 April 2020 (UTC)
Oh and there are some very nasty bacterial respiratory infections, like diptheria, tuberculosis, and scarlet fever. Tuberculosis was the second-highest reported cause of death in the U.S. in 1900! We just happen to have made huge progress against many of these with antibiotics, vaccination, improved sanitation, and other modern health measures, but TB in particular is still a huge problem in poorer countries. Show your appreciation for this by making sure to keep your vaccines up to date! --47.146.63.87 (talk) 22:14, 2 April 2020 (UTC)

Just looked this up since I didn't know the answer. The minimal infectious dose of E. coli varies as one might have expected depending on the strain. The major factor being the presence of shiga toxin, which causes gastrointestinal hemorrhaging. The most benign pathogenic strains have minimal infectious doses of over a million viable cells, while the most pathogenic can establish an infection from less than ten [10]. Someguy1221 (talk) 12:10, 3 April 2020 (UTC)

# April 4

## What species is shown ?

Here What species is shown ?

2003:6:13D3:F133:615D:ED00:9E14:2CA4 (talk) 21:18, 3 April 2020 (UTC)

The overall appearance and especially the venation of the wings looks like drosophilidae, but I wouldn't know how to tell which species it is by eye. Someguy1221 (talk) 06:57, 4 April 2020 (UTC)
Could it be a horn fly?  --Lambiam 07:35, 4 April 2020 (UTC)

Honda bulb