Wikipedia:Reference desk/Archives/Science/2020 April 2

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April 2

Why developed countries have more deaths due to Coronavirus

https://www.worldometers.info/coronavirus/#countries

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 (talk • contribs) 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)

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3556998&mod=article_inline 89.172.105.142 (talk) 16:04, 6 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. Tigraan^{Click 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)

The number of tests done vary depending on healthcare system. USA, Spain and Italy are the world leader in TESTS we do not have the data about the death or the total cases. Iluvalar (talk) 16:18, 6 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 [1]. Someguy1221 (talk) 12:10, 3 April 2020 (UTC)