Wikipedia:Reference desk/Archives/Science/2019 June 20

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June 20

Likelihood of death from influenza

Hello. As a general question, if a person contracts influenza, how likely is it that he or she will die as a result? An approximate answer is OK. I gather that people are more likely to die of this condition if they are very young or very old. Is that correct? FreeKnowledgeCreator (talk) 00:50, 20 June 2019 (UTC)

Quoting from our article Influenza, "Influenza spreads around the world in yearly outbreaks, resulting in about three to five million cases of severe illness and about 250,000 to 500,000 deaths." This implies a death rate of about 10% for those with "severe illness". The Spanish flu pandemic of 1918-1919 killed approximately 50 million people. It began in the final months of World War I and ravaged the planet. The virulence of the dominant strain of flu varies from year to year. The elderly are always very vulnerable especially if in poor health, but some strains seem to affect younger people more than others. On a personal note, my grandfather's first wife died in 1919 in that pandemic, and she was in her 30s. He remarried my grandmother a couple of years later, and I am the son of my grandfather's youngest child, my mother who was born in 1930. If it had not been for that pandemic, I would not be alive today. Every cloud has a silver lining. Cullen³²⁸ Let's discuss it 01:08, 20 June 2019 (UTC)

The different strains can have very different mortality rates, and the availability of hospitalization also has a big effect. Then there's difficulty in calculating just how many people actually have the flu each year, as mild cases and the many other conditions that produce flu-like symptoms are never distinguished for those who don't seek medical attention. And yes, the young and old, and people who are otherwise immune compromised or just in poor health are at much greater risk. Our article puts the average number of deaths each year in the US at 36,000-41,400, which would put death in the range of 1 out of every 1000 cases (the death rate is much higher for those hospitalized with the flu). Also see [1]. However, some strains can kill millions, such as the 1918 flu pandemic (Spanish flu) mentioned above. SinisterLefty (talk) 01:11, 20 June 2019 (UTC)

Just to build on the above, it seems that some strains of flu trigger what was known as a cytokine storm, but which now is known by the much less cool name of "cytokine release syndrome". In instances such as that, the healthy young adults experience much higher mortality as their own immune systems spin out of control - the 1918 pandemic in particular has been identified with this. Matt Deres (talk) 14:38, 20 June 2019 (UTC)

Anti-venom

How is anti-venom made, in layman's terms? I know they need to extract or milk snakes to get venom to be used in the creation of anti-venom, but how? Thanks Anton 81.131.40.58 (talk) 10:47, 20 June 2019 (UTC)

Inject a survivable amount of venom into an animal, perhaps a rabbit, and then collect and purify antibodies against that venom out from the rabbit's blood. Alternatively, collect white blood cells from the rabbit and screen for ones that secrete antibodies against the venom, then grow those cells in a laboratory to make as much as you want without wasting more rabbits. Read more at Antibody#Research_applications. Someguy1221 (talk) 11:07, 20 June 2019 (UTC)

Snake antivenom. DroneB (talk) 12:21, 20 June 2019 (UTC)

Why do news stories about someone who was snakebit commonly refer to it as the synonym "antivenin?" Edison (talk) 14:34, 20 June 2019 (UTC)

It's French. It's also called antivenene. Matt Deres (talk) 14:54, 20 June 2019 (UTC)

In some English-speaking countries "antivenin" is the word. It's not a kind of venom, so "anti-venom" looks like an error. --76.69.116.93 (talk) 22:34, 20 June 2019 (UTC)

EO says "antivenin" dates to the 1890s and that the trailing "in" may be a chemical suffix.[2] ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:29, 21 June 2019 (UTC)

In Australia most of the anti-venenes are made using horses rather than rabbits. Treatment using this serum on a person for more than one episode can trigger an allergic reaction to horse serum on the second or third use. Hence most snake-handlers who get bitten try to not use the anti-venene unless/until it is absolutely neccesary. 49.197.107.84 (talk) 06:56, 21 June 2019 (UTC)

Are toothpastes exercises in branding?

I saw a new brand of toothpaste at the drugstore, parondontax, whose sole active ingredient is stannous flouride, or tin(II) fluoride. That's no different from, say, Crest Pro-Health, except maybe in price and manufacturer (gsk). What's the diff? 104.162.197.70 (talk) 11:56, 20 June 2019 (UTC)

Everything like that is an exercise in branding, more than anything. But stannous fluoride is a good thing, and not universal, even in fluoride toothpastes, as most of those still use sodium monofluorophosphate (MFP). Andy Dingley (talk) 12:13, 20 June 2019 (UTC)

I believe stannous fluoride is the least effective toothpaste and sodium fluoride in in the middle and sodium monoflurophosphate is the most effective of the 3 fluoride toothpaste ingredients available in the US not sure about non fluoride toothpaste but I do know in the US at least Crest mostly uses sodium fluoride and Colgate mostly uses sodium monoflurophosphate and stannous fluoride is in the sensitive products as it irritates teeth the least of the fluoride toothpastes 64.222.180.90 (talk) 18:33, 20 June 2019 (UTC)

Our articles on the relevant chemicals disagree with you about the relative effectiveness (for various meanings of that term) and have some citations to support. DMacks (talk) 19:16, 20 June 2019 (UTC)

Products are about more than just the active ingredients. Take alcoholic drinks. Alcohol is the only "active ingredient", but the other ingredients make all the difference in the experience. In the case of toothpaste, there's whiteners, breath fresheners, tartar reducing agents, flavors, etc. SinisterLefty (talk) 03:50, 21 June 2019 (UTC)

It's hard to recommend specific toothpastes without seeing the patient (so talk to your hygienist, this can actually matter). For most people, most good toothpastes are equally good. But there are some patients where there will be variations. If you suffer from a dry mouth (for whatever reason), then stannous fluoride is certainly preferable to the sodium fluorides, for its antibacterial effect compensating for that normally provided by saliva. If you suffer from staining after stannous fluorides (rare, but it can happen), then the better toothpaste formulations have ingredients to deal with that, which cheap ones might not. But it's a relatively rare problem, specific to some patients, and if you haven't got the problem, you don't need the solution. Andy Dingley (talk) 11:16, 21 June 2019 (UTC)