Monday, March 30, 2020

Grape diversity is not the only biodiversity that vineyards need

The wine industry has become increasingly aware that it must address climate change, as I have written about recently (Climate change and the most northerly vineyards in Europe). In particular, the concept of biodiversity means that reliance on a few grape-vine varieties is inappropriate for long-term profitability (Regional diversity of grape varieties is important for climate change).

Equally important, however, are agricultural practices, and their affect on the world. It is therefore worth asking: how does this affect the wine industry? After all, traditional viticulture involved completely clearing the native plants and animals, and turning the land into a regularly plowed monoculture.

This image does not look good in the modern world, where biodiversity counts. How do we explicitly address what are now increasingly accepted as unacceptable previous practices? I will discuss that here, including looking at a new idea that is currently being explored.


When I was being trained as a professional biologist, in the late 1970s, biodiversity was the Big New Thing. The Western world had changed during the 1960s, and people had started to become conscious of their environment. Not just their own personal environment, which was often a city, but the natural environment, on which their local environment critically depends.

The turning point for many people was Rachel Carson’s book Silent Spring, first published way back in 1962, which strongly made the point that contemporary agricultural and forestry practices were changing the natural environment in unintended ways. These ways were starting to have direct and indirect affects on people’s personal lives.

For biologists, a key component was, and still is, that the biological world has innumerable interactions among its components, only some of which we can easily see. When A affects B, which then affects both C and D, and D then affects A, we cannot always see, and thus predict, this feedback loop. We see it only afterwards — we have 20:20 hindsight, not foresight. The concept of complex and far-reaching interactions was poetically, but aptly, expressed as: When a butterfly sneezes, the polar bears tremble.


So, agricultural and forestry practices are under public pressure to change. We now have the expression “sustainable agriculture”, although it is unclear just how we should identify it or assess it in practice. It has to do with recognizing the complexity of biological interactions — sowing, growing and harvesting practices must all be carried out in ways that recognize their long-term affects on the local soil, water and air. Next year’s harvest depends just as much on last year’s practices as it does on next year’s.

Sustainability is a long-term goal, and (let’s get this clear) a laudable one; and yet we have only been discussing it for a short while. How can we know, in such a short time, which practices are actually sustainable? Olden practices were sustainable, in the sense that we successfully carried them out for hundreds of years. However, since the Industrial Revolution in the late 1800s, we have made innumerable rapid changes, none of which we have yet assessed long-term —except with the hind-sight of seeing their unintended, and sometimes unfortunate, consequences.

We also have the expression “organic agriculture”, which is not very explicit, but seems to have something to do with not using artificial agricultural treatments. (See How to make sense of sustainable wine certifications, for an explanation of the confusing array of possible wine terms.) This approach to agriculture also seems like a good idea, although it is often questioned just how “natural” some of the recommended treatments actually are, or just how much better they are than the so-called artificial ones.


The main purpose of natural treatments is that they are likely to have far less affect on the local biodiversity than are chemicals that were designed solely to target a particular part of that biodiversity. A weed-killer, for example, is intended to kill unwanted plants, but it is also likely to kill other plants at the same time; and a pesticide is intended to kill unwanted animals, but it is also likely to kill other animals, as well. So, we may choose to spray, but we must think very carefully about what we are spraying, and what we are spraying it onto.

An alternative, however, and the one favored by professional biologists, is not to spray in the first place, but to “fight fire with fire” (although not all grape-growers may like that particular analogy, just at the moment!). That is, we use one part of the biodiversity to control another part. To do this, we must study the existing biological interactions, and work out whether there is something that we can use to achieve our goals, without stuffing up everything else at the same time. This is not easy, by any means, but it is likely to be both organic and sustainable, because it helps preserve the biodiversity, both of the crops and their surrounding environment.

So, while diversity of grape-vine varieties is important in the modern world, it is not the only biodiversity that vineyards need — they need to preserve as much of the natural biodiversity as they can. They can do this by becoming a part of their local environment, rather than trying to be separate from it. A neatly plowed vineyard may look nice and orderly, but its biodiversity is very low, and unnecessarily so.


Therefore, these days we are just as likely to see a vineyard full of other plants between the rows, rather than bare earth, perhaps kept in check during the off-season by grazing sheep. You don’t want the animals eating the new grape-vine shoots, but if you pick animals that are generally grazers not browsers, then the vines should be safe. Cows are bit big for vineyards, and goats are generally browsers, but sheep are quite suitable for allowing biodiversity to exist in the vineyard while not interfering with grape production. These days, tractors and herbicides are out, and cover crops (biodiversity) are in.


That leaves us with the matter of animal pests. Two recent articles from the southern hemisphere discuss potential modern approaches, especially if you are not hide-bound by European traditions. [Note: this post was written several weeks ago, so the news reports are not quite as current as they originally were.]

One article, Villa Maria trials native plants as herbicides alternative, lays it on the line in New Zealand. Native plants have mechanisms for dealing with native pests, and the presence of some of them in the vineyard may very well assist the grape-vines, as well. That is, the ground cover shouldn’t be some introduced grasses and herbs, but should be some collection from the local flora. Which ones, we do not yet know, so it is about time we found out.

The other one, EcoVineyards: the future for pest-resilient vineyards, does the same thing for Australia:
The main principle is for growers to introduce native plant species into their vineyards, to support populations of beneficial insect predators that will contribute to the biological control of vineyard pests. The inclusion of insect predator species in vineyards can potentially lead to reduced input costs, a reduction in the use of chemicals, and an overall improvement in the environmental sustainability of wine regions.
There are, of course, similar moves in the northern hemisphere. As but one example, recently there was a Hands-on vineyard workshop on Lodi beneficial insect plants, for the growers of San Joaquin Valley “to learn more about why, what and how to plant rows of native California plants known to boost the population of beneficial insects in a given area as much as 28 times over.”


So, pesticide sprays are out, and biological control is. Under these circumstances, the words organic and sustainable start to have some real meaning for the modern world.

Finally, it seems that there will soon be a way for the wine industry to properly see the relationship between each vineyard and its surrounding environment. The Somm Foundation has now announced the Global Diagram of Wine. This lets you see the vineyards interactively, within their topographical and biological context. We are told that millenials want to interact with their lifestyle products, and this is perfect for that — it is, however, not (yet) free. Professionally, it would also need a soil map and some climate data, to be perfect; but these will come.


Conclusion

There has never really been any sharp distinction between Old and New World wines, but instead a continuum of styles between two extremes. However, agricultural practices have often differed significantly. In response to the modern world, those practices need to converge on something acceptable to modern consumers.

Moreover, for the wine industry to compete in the modern alcohol market, every step of the production process needs to be demonstrably committed to modern practices. We cannot just point at the grapes, as I discussed above, but the rest of the process, as well, including bottle and label production. One comprehensive example is provided by recent changes in the range of Regal Rogue vermouths.

Monday, March 23, 2020

There seems to be a lot of public misunderstanding about the coronavirus

This blog is supposed to be about the wine industry, not viruses, but the effect of the current coronavirus pandemic on the wine industry is clear for all to see. Worldwide, there is everything from panic buying to empty bars and restaurants to closed shops and wineries. Financially, it will take a long time for things to settle down in the hospitality industries; as it also will for many if not most other industries (the travel industry, in the broad sense, may possibly be worst hit of all).

The current coronavirus pandemic is being treated as the worst for a bit more than a century. Therefore, as a biologist, I cannot sit by while reading so much confused commentary on the current situation. The media is full of confusion; and sometimes even the quoted experts are not being sufficiently clear. Note that I am not talking about the blatant mis-information and moralizing currently appearing on Facebook and Twitter, which is nothing more than personal opinions from often ill-informed people. I am talking about the professional media, who in many cases seem not to understand the topic, at least to date.

To me, the main source of confusion is about the difference between the virus itself and the disease that it causes. They are not the same thing, by any means; and it matters greatly to the discussion, and to how we should react to the pandemic. Sometimes the media are writing about the one and sometimes about the other, even in the same sentence, and even using the same words. How can the general public possibly be helped by this? In this post, I try to remedy this by distinguishing which bit of the discussion refers to which.


I have some background in infectious diseases, so I thought that it might be worthwhile to try to clarify the biology, for readers of this blog. This is a long post, but it will give you something to read while you are in quarantine. It is based on what I have read, and understood, in the professional literature, as well as expert commentary. I offer no personal advice for any of you, just commentary, which you should take on its own merits — I have a PhD not an MD.

The virus

So, to get things clear, the virus is officially called SARS-CoV-2. It is one of several types of coronavirus, some of which have proven difficult for humans over the past few decades (eg. SARS-CoV and MERS-CoV).

The virus has a small genome enclosed by a lipid (fat) layer. There are currently two known strains, meaning that they have slightly different genomes. It is not yet known whether the difference has any important consequences for their infective behavior.

We act as the living host for the virus, and normally it cannot function outside a host. However, the lipid membrane of cornoaviruses allows them to easily survive (inactive) in the outside world — in the case of this new one, for up to 3-5 days on some hard surfaces, like metal, glass or plastic (other coronaviruses can last even up to 9 days).

In order for you to become a host to the virus, you need to get one (or more) into your body through some of your so-called mucous membranes. It cannot get through your skin, but it can get in through your nose, mouth and eyes. So, you can pick it up through the air from someone within about 2 yards / meters of you, if they cough or sneeze, which produces respiratory droplets. Alternatively, if you touch a virus-infected surface, such as a door-handle, a stair-rail, or a trolley in a supermarket, then it will be on your hands. People touch their faces with their hands at least once every 3 minutes or so (on average), in which case you run a big risk of infecting yourself.

You can now see why you are being given instructions to keep away from each other (air transmission), and to wash / disinfect your hands often (surface transmission). Soap, alcohol and even bleach all seem to work to clean your hands. You could also try rinsing your face, when you come indoors. Perhaps the toughest issue for people is the length of time during which a virus-infected surface remains dangerous — regular and thorough cleaning is the only remedy.


The disease

But all of this has nothing to do with the disease. A disease is a reaction by your body to some other organism, be it a virus, a bacterium, a fungus, a plant or an animal. Most disease-causing organisms are harmless to almost all other organisms. That is, each type of virus has only a limited range of hosts in which it can survive; and, even then, many hosts are not actually badly affected.

The primary host, however, can be seriously affected, in many cases. In our case, our response to coronaviruses is a respiratory inflammation, which in its worst form is a type of pneumonia. This pneumonia may even be fatal, especially for people whose lungs have been adversely affected in the past, and are therefore not in prime condition. The same situation is the case of other coronaviruses, like SARS-CoV (causing Severe Acute Respiratory Syndrome) and MERS-CoV (causing Middle East Respiratory Syndrome). In the current pandemic, SARS-CoV-2 causes the disease we have called Covid-19 (the “d” in that name stands for “disease”).

So, it is the disease that is called Covid-19, not the virus. This makes all the difference to understanding what people are talking about in the media. The main point is that being infected with the virus does not necessarily mean that you will develop the disease.

The experts are now beginning to suspect that, in fact, many people do not develop the disease, even after they get the virus. These symptom-free people can still pass the virus on to others, of course; and those others may very well develop the disease. That is, having the virus does not necessarily make you “sick”; but, unbeknownst to them, people should keep away from you.

There is nothing unusual about this situation for infectious diseases. For example, when I was young, my father developed tuberculosis (which is caused by a bacterium). My sister, brother and I were all tested, of course, to check for exposure. My brother’s test indicated that he had acquired the bacterium, but he did not develop the disease; neither my sister nor I had picked up the bacterium.


The current situation

This should help clarify the current media information. All of the data being bandied about in the media refer to the disease (Covid-19), not necessarily the virus. We can tell when people develop the disease, because they have certain symptoms (including fever, cough, shortness of breath). So, the experts can tell us what percentage of the people have developed the disease, and what percentage of those have subsequently died.

At the moment, it seems that roughly 80% of Covid-19 cases are mild (with flu-like symptoms), and the people can recover at home. Another 15% of cases are severe, developing a pneumonia, and often require hospitalization. The remaining 5% become critical patients, often with respiratory failure, septic shock, and even kidney failure; and these people may very well die.

So, getting the disease is unpleasant but not dangerous for most people. The other 20%, on the other hand, will have problems. Fortunately, depending on your age and medical condition, the virus may not be a big issue for you, at all.

Clearly, the most densely populated areas are generally the ones with the biggest infection rates. Person to person spread is much greater when more people live near each other. Spread is also greater when more people are in a small space, such as at public gatherings and workplaces. This may yet turn out to be the most easily spread virus we have encountered.

There are sufficient data to indicate a fairly direct relationship between disease severity and patient age — 70+ years old is the major risk group, with a death rate of c. 20%. Pre-existing medical conditions also seem to be very important for actual survival, notably cardiovascular disease and diabetes, but also lung conditions (eg. from smoking, or asthma) and hypertension (high blood pressure). That is, being older makes you more susceptible to Covid-19, but it is the combination with other medical conditions that will do you in. (Note: given this information, I am on the border of the main pandemic risk group.) It seems that healthy lungs are a key survival characteristic. This benefit cannot exist as we get older, of course, because of all of the colds, flus, etc, that our lungs have previously had to cope with.

On the other hand, what the experts cannot tell us yet is how many people have picked up the virus. It now seems clear that this might well be a large number, far greater than was previously thought (it was originally estimated at 1.5-3.5%). People with only mild, or even non-existent, symptoms seem to exist, especially among the young. In some cases, the symptom-free period is relatively short, but in others it is much longer. So, the reported Covid-19 data are missing three groups of people, of unknown size:
  • those who show no symptoms or are only mildly ill (unreported cases)
  • those who have been missed, because there hasn’t been enough testing (unreported cases)
  • those who are currently incubating the virus but have not yet shown symptoms (pre-clinical cases); this period can be up to 14 days.
You can now see the confusion. For example, when we are told in the media that mst of us, or even all of us (in some predictions), may be affected by the pandemic, it is a reference to the virus, not the disease, even if the media reference is to the name "Covid-19". This information is no reason to panic, because it does not mean that we will all get sick (or die), but merely that we will pick up the virus. We need to know the virus-infection rate (what percentage of people get the virus), as well as the disease rate (what percentage of virus-infected people develop the disease), before we can understand what the implications are of these expert predictions.

In order to get this information, we would have to test a large number of people, irrespective of whether they have ever had symptoms. The medical world is currently over-loaded in most Western countries (where the infections are concentrated), and there is neither the person-power nor the required test kits to do this. Indeed, even the current testing has caused chaos, especially in the USA, which has had a woefully low testing rate (hampered by delayed and faulty test kits), as it requires DNA testing (slow and expensive).

So, it may still be a long time before we could even begin the task of collecting infection data. On the positive side, test kits have now been announced that would allow us to more easily do the required testing. These do not test for the presence of the virus itself, as do the currently used tests. Instead, they test whether your body has reacted to the virus. In response to infectious diseases, we produce antibodies, which help us counter-act the disease-causing organism. These antibodies make us safe from future infections by the same organism. The new tests look for the presence of these antibodies; and this is much more efficient and cost-effective than the current tests. (Note: this is the basis for the tuberculosis test that I mentioned above.)

Some countries have shown a resurgence of infections, after a first boom in Covid-19 cases (eg. Singapore, Taiwan, Hong Kong), which is not an unexpected scenario. The problem is the existence of the three groups of people listed above as currently unreported and pre-clinical cases. There may be many more infected people running around any well-populated country, ready to infect new people when travel restrictions are lifted, and the unexposed people come in contact with the infected ones. So, influenza-like epidemics are known to start with a bad (and dangerous) burst, calm down for a while, and then break out again.

It is for this reason that there are suggestions that the circulation of the virus may last for up to a year, in total, with maybe 80% of people infected, and up to 15% of people hospitalized with the disease. This does not mean that the current disease (Covid-19) situation will continue for a year, but that the virus (SARS-CoV-2) will still be around.


Recent experiences

What can we learn from the pandemic so far, that might tell us how to react now? Different countries have applied different response policies, apparently based on differing cultural traditions and social behaviors. We know some strategies that have worked so far, and some that have not, depending, I guess, on your own cultural expectations.

The Chinese reacted rapidly to the spread of the virus, once they had officially acknowledged that it exists. They were immediately authoritarian, and severely limited personal travel, and this seems to have been effective at restricting long-distance spread — their disease rate is low (compared to many countries), although given the massive size of their population that still means a lot of people developed the disease. For several days now, no new confirmed or suspected cases have been reported in Wuhan or Hubei province, the original epicenter; and all new cases are imported from overseas (ie. no new domestically transmitted infections). China is already waking from its shutdown.

The Vietnamese seem to have succeeded in a similar manner, which was a necessity given their dense population and relatively poor medical system. They even wrote a special jingle for children about the need to wash their hands.

The South Koreans reacted very differently, by instituting a massive testing program. They did this because the main source of their infections was a secretive religious organization (responsible for more than 60% of the national infections), all of whom were compulsorily tested. This was expanded to include a large portion of the rest of the populace, as well (without any lockdown or other authoritarian measures).

The Iranian government, on the other hand, should all be charged with manslaughter. It seems that they officially hid the initial infections because of their potential affect on the turn-out at impending elections. They officially announced the presence of the virus on the same day as they reported the first death, which means that the virus had been circulating in the populace for weeks. Consequently, they are still reporting more deaths per day than almost anyone else.

As for Italy, a Nielsen survey early on reported that <20% of Italians were concerned about the virus and the possibility of a widespread epidemic. So, no-one did anything official until it was far too late. Studies have now clarified why they have had such a problem, and why Spain is now in such a similar situation. It appears to be family structure — the social importance of the extended family, as opposed to the nuclear family of two adults and two children, which is so prevalent elsewhere in the Western world since World War II. In the extended family, grandparents often regularly look after their grandchildren, especially if the parents commute to work. The grandchildren pick up the virus during the day, but do not develop obvious symptoms (they are in the healthy-lung non-risk group, remember). They do, however, bring the virus home to their family, who are not resistant, especially the grandparents.

This explains the disease infection rate, but not the death rate. The latter comes from the fact that Italy also has a large proportion of older people — 25% of the populace are >65 years old (for comparison, it is more like 16% in the USA). This has sadly been a lethal combination: an extended family structure and a large group of people at risk. Spain apparently has the same combination.

Japan is another country with a high proportion of elderly people (28% are >65 years), and has therefore been at great risk. However, they have stuck much closer to the nuclear family structure, as have the Chinese in recent decades. This seems to have helped limit the virus spread locally. Another important point is that older people do not often live alone (c. 10%), so that they do have family support coping with illness (compare with c. 25% in North America).

Germany and the Scandinavian countries have so far fared quite differently. They all have relatively high infection rates but so far quite low death rates. It seems that the infected people have generally not been in the high-risk groups. In the case of Germany, the health system also has more critical-care beds per capita than most other countries, which certainly helps. In the case of the Scandinavians, almost all of the initial infections came from people who went downhill-skiing in Austria and northern Italy, during the school break weeks. These people are likely to be younger, and relatively healthy. It remains to be seen how the situation changes as the virus spreads to other groups within these countries — at the moment, the critical-care patients in Sweden are mostly 50-70 years old, rather than >70.

Other countries have (very belatedly) imposed draconian social measures to limit viral spread, starting with the banning of large group meetings, then the closing of non-essential services — the USA is currently arguing about whether retail alcohol sales constitute essential services. In many places, there is now the banning of personal movement without a compelling reason. (Here in Sweden, limited movement is government advice, but not mandatory, so things seem relatively normal, although very quiet.)

This may be a useful strategy, but it is clear that many people do not understand it. You may have read that in Sydney (Australia) many of the people who had been told to stay away from work went to the beach, instead, because it was a sunny day. The sight of a crowded beach tells you just how little some people understand about a pandemic situation. Keeping 2 yard / meters apart gives everyone 40 sq.ft or 4 sq.m of disease-free space. Your governments are telling you to keep apart from each other, rather than barricade yourself in your home.

Sadly, this is also generating a backlash among some young people. Some of the people <25 years old have realized that most of them have natural resistance to the disease (healthy lungs), and so they are not concerned about getting the virus. They are now asking the obvious question: “why are we being quarantined, as well?” Once again, this question fails to distinguish the virus from the disease — not having the disease is different from not having the virus, which you can then spread it to others. We all know that the young will inherit the Earth, but the obvious answer to their question is: “because you don’t want to give the virus to your parents, and especially your grandparents, and thus inherit sooner rather than later.”

Some countries have had to start asking serious ethical questions. If the number of disease cases overwhelms the national medical system, then it becomes necessary to ask: “what order should people be medically treated, and for how long?”, and “whose lives should we try to save?” This assumes, of course, that the system can save lives from Covid-19 infection, which is not at all certain. A similar thing applies to the economy — lockdowns will drive many organizations bankrupt (particularly in the hospitality and tourism industries) but is intended to slow the virus spread. This assumes, of course, that the lockdown will be effective in the long term.


Possible strategies

The rate of disease spread is related to how many new people are infected by each currently infectious person. For the seasonal flu virus, this is c. 1.3 people, but for SARS-CoV-2 it seems to be higher, c. 2.8, denoting twice the exponential rate of spread. It is this number that it the key to why this has become a pandemic, whereas previous coronavirus outbreaks did not. The ease of infection spread is unprecedented for coronaviruses.

So, what containment strategies might work in the near future?

Closing national borders is unlikely to have as much effect as people might hope. It is far too late to keep the virus out, although it might help keep it in. There are too many exceptions to the closed borders (eg. nationals coming home, goods coming in) for complete containment. However, China is reporting that most of its new cases are among foreigners, not locals, so keeping them under control is not entirely useless.

The obvious downside is that shutting borders merely shuts the virus in, rather than keeping it out — it does not prevent spread within the closed borders. In China's case, the travel restrictions did not help Wuhan, where the virus originated, but did help the rest of the country. The upside is that it can slow the virus spread, so that the health-care facilities do not get overwhelmed — we actually need Covid-19 cases to appear slowly over time rather than all at once. That is, we do not actually want a big pandemic burst, to “get it over and done with”, because the health-care facilities cannot handle that scenario (as we can see in Italy).

In theory, closing schools is probably the single most effective thing that could be done, for families. This is not to protect the children, because they already have their own in-built healthy-lung resistance. Instead, it is to prevent them from picking up the virus from each other, and then bringing it home to their as-yet-uninfected family. Having sick parents is bad enough, but we don't need the kids to find out that they are the ones who made their parents sick in the first place. The practical consequences of closing schools, on the other hand, have been hotly debated, the biggest issue being that the people whose children are at home, instead of at school, may have to stay at home with them, including those who are running essential services (nurses, police, etc). As noted above, the grandparents should probably not fill the child-care role.

Working from home would be a good strategy for adults, if they can do it. This is obvious — you can’t get the virus from people you don’t meet. Try to keep away from public transport, for the same reason, along with live sporting and theatrical events, plus gambling dens. You might also prefer supermarkets where the staff wear gloves, and don’t insist on long queues at the checkout. These changes can lead to you to going stir crazy at home, of course, especially if you cannot get some dedicated personal space; and it can put a strain on your family life. There are now plenty of new online videos offering you advice on how to make it work. Have a wine tasting with your spouse, not an argument; play games with the kids, rather than yelling at them. Do not take up online poker — it is illegal throughout most of the USA.

The virus-testing of health-care professionals (of all sorts, including dentists) should probably be mandatory, and it already is in many places. These people are the ones most likely to get the virus, and also the ones whom we can least afford to have spreading it. Indeed, those people who work on infectious diseases seem to all understand that they will pick up something nasty, sometime in their professional lives. This happened, of course, with Li Wenliang, who was the first person to note the Covid-19 disease, last December, and who then died of it in February.

The common “medical” face masks that you sometimes will probably be useful if you are the one infected, and are trying to not spread the virus via your own respiratory droplets (in surgery, it is the medical staff who wear them, not the patients!). Otherwise, they do not necessarily prevent you from picking up something as small as a virus, even if you wear them properly (which most people don’t). An industrial dust mask will work, but they are too awkward and uncomfortable for long-term use.

Keeping the elderly away from younger people seems like a good idea, especially in aged-care facilities. Being with other older people may actually be okay, funnily enough, because they are the primary risk group, and if they have the virus then they will probably show symptoms, and you can then keep your distance. Sadly, since people are infectious but symptom-free when they first get the virus, you would be relying on the elderly showing symptoms fast (eg. 2 days not 7 days). However, Florida should consider closing its borders — this may actually be the single most effective thing the U.S. government could do for the elderly. Having children checking on retired parents, to see whether they are okay, may actually do more harm than good; use a Skype call, instead. The same thing applies to any sick people that you may know.

There is currently no officially recommended antiviral therapy for treating Covid-19. However, Remdesivir has been an effective pharmaceutical for other coronaviruses, and it is now being formally evaluated for Covid-19. This was originally developed for treating filoviruses, such as the Ebola virus, but it seems to be the best bet compared to all of the HIV and influenza drugs that have tested so far, although Lopinavir, Retonovir, Oseltamivir and Chlorphenamine have apparently also been recommended.

Being out in the open air away from other people will stop you from going stir-crazy, and might very well be safe. Indeed, if doing this is not okay, then we really are in the worst-case situation. A round of golf, during which you touch nothing but your own clubs and balls, and wash your hands when you get home, may do more good than harm for most people.

Hoarding toilet paper and dried beans is embarrassing, but it may indeed be necessary if your government bans you from putting your head outside your own front door. Whether you have health insurance or not does not matter in a national emergency — biology does not care about your social status, only your biological status. Everyone from government officials to Hollywood actors to international athletes to Formula 1 teams can get the virus, and have done.

Do not blame the Chinese, just because the virus happened to arise in Wuhan, in China. After all, the biggest pandemic in history, which killed more people than all of the military and civilian casualties of World War I and World War II combined, came out of the USA. The fact that history has called that disease The Spanish Flu does not hide the origin of the influenza virus in Haskell County, Kansas, in 1918. Viruses can arise anywhere at any time — people who live in glass houses should not throw stones.

Finally, do not panic, and do not prophecy Doomsday. Coronaviruses are usually not re-infectious — once you have produced your antibodies, you are likely to be safe. This has not yet been experimentally shown for the current pandemic, but early tests on the usual test organisms (macaque monkeys) have been positive.

Biologically, the only long-term safety is this form of immunization, which occurs when you are actually exposed to the virus. This leads to what is called “herd immunity”, in which most people are uninfected because they are now immune, so that those people who have not yet been infected are unlikely to encounter an infectious person — they remain safe, too. This is somewhat risky, of course, since it involves us all getting the virus at some stage. However, there is every reason to expect that a much safer immunization procedure will be forthcoming (although not for at least a year).

Monday, March 16, 2020

Is there value-for-money in the Wine Spectator Top 100 List?

There are two extreme ways to purchase wine.

First, wine can be bought using price alone. This appears to be based on the idea that wine is simply flavored alcohol, and any alcohol will do. This may be true, but it does not seem to result in the purchase of wine that is worth tasting, as repeatedly demonstrated by Jeff Siegel in his $3 Wine Challenge.

Second, wine can be bought based on a quality score assigned by some critic. This appears to be founded on the idea that either: the critics know what they are talking about, or my friends and colleagues will be impressed by my knowledge and/or wealth. The latter is called “wine snobbery”, while in the modern social-media world wine critics may be redundant.
Somewhere in between these two extremes is the idea that wine could be purchased on the basis of value-for-money, which is intended to reflect some balance between the two extremes. That is, we buy the cheapest wine that meets some specified standard of quality.

A number of web sites specialize in providing suitable advice, some of which I have listed in a previous post (Finding inexpensive wines). For myself, I have suggested an explicit mathematical approach, which involves looking at the relationship between quality and price for a range of wines (Calculating value for money wines).

I do not expect people to actually do this math for themselves, although it is certainly effective. The idea is to fit an exponential model to a graph of the data. This model assumes that price increases exponentially with quality — that is, for each unit increase in quality the price is multiplied by some constant number, rather than adding a constant price. Sadly, this relationship applies widely throughout the world of economics, although it means that prices increase rapidly with quality.


In this regard, it is interesting to ask whether this idea applies when we focus solely on the high-quality end of the market. The idea might apply across a wide range of quality levels, but does it still apply when we focus on a narrow range?

One way to investigate this for wine is to look at the so-called “best wines” as announced by some set of critics, such as those that congregate in a wine magazine. The obvious one to pick is the Wine Spectator, which produces an annual Top 100 List — this is intended to include what they perceive to be the best 100 wines of those that they have reviewed in the previous 12 months “based on quality, value, availability and excitement”.

The graph below shows those 100 wines for the year 2019 (based on independent blind tastings of >15,000 wines). Each point represents one or more wines, based on its quality score (horizontally) and price (vertically). Also shown is the line for the best-fitting exponential model (as described in the top-left corner).


The idea is that, for wines near the line, you are paying for what you get (in terms of quality) and getting what you are paying for (in terms of money). Above the line, the wines are increasingly poor value-for-money (you can get the same quality for much less money), while below the line they are increasingly better value-for-money (some other wines cost a lot more for the same quality).

The first thing to notice is that the exponential model does fit quite well — 69% of the variation in price is related to quality. In the world of economics, this is pretty good. That is, the wineries really are charging you more money for what the Wine Spectator sees as increasing quality. We could, indeed, use this model to identify those wines that are the best value-for-money.

The next thing to notice is that the biggest range of value-for-money is at 95 and 96 points. There is everything from good value (at the bottom of the graph) to the biggest rip-offs (at the top). The Wine Spectator has certainly not used “value” when deciding to include those wines at the top of the graph (> $140) — it must therefore reflect “excitement”.

On the other hand, up to 93 points the wines are almost all good value. The exception is the Domaine du Castel Grand Vin Haute-Judée 2016, which costs all of $85 for only 91 points.

On the other hand, the best value seems to be the Tenuta Bibbiano Chianti Classico Riserva 2015, which costs a mere $30 for 96 points of quality.

So, there you have it: yes, good value-for-money can be found in this Top 100 list — go for the highest-scoring wine at $20, or the cheapest wine at your favorite score. There is also, of course, some very poor value-for-money, but in those cases you are getting vinous excitement, instead.

In a future post, I will look at the whole range of Wine Spectator Top 100 lists over the past 32 years.

Monday, March 9, 2020

Which countries are similar to each other, in terms of their grape varieties?

A couple of weeks ago I noted that Regional diversity of grape varieties is important for climate change. The basic point is that with changing environmental conditions, we need a range of grape-vine varieties available, so that we can see which ones do best under the new conditions.

A related issue is, of course, what varieties are available at the national level. After all, the existence of varieties is not of much practical use to you if they are not actually in your country. One major concern that is sometimes expressed is about the diversity of wine-grapes narrowing down to a few so-called “international” (noble?) varieties — after all, 13 grape varieties cover one third of the global vineyard area. These are often presented as mono-varietal wines, which results from trying to maximize short-term economic returns, rather than planning for the future.


We can look at this issue with the same source of data used in my previous post, the Database of Regional, National and Global Winegrape Bearing Areas by Variety. This compendium has vineyard area data (in hectares) from 2010, for 1,446 named grape varieties in 48 grape-growing countries. You will never have heard of the vast majority of these varieties, as there have probably been at least 10,000 of them recorded at some time in history.

What I wish to do with these data is to examine just how similar the countries are to each other, in terms of the abundance (area) of these grape-vine varieties. This can be conveniently displayed as a network, as I have done in a number of previous posts. [Technical note: the relationships among the countries were calculated as Bray-Curtis distances, and the NeighborNet graph was drawn using the SplitsTree program.]

I have included the network at the bottom of the post, for those of you who would like to see the details. Here, I will simply summarize what the network tells us about the relationships among the cultivar varieties of the different countries.

1. There is no strong pattern in the network, as there has often been in my previous posts using networks. So, there are no clusters of distinctly different countries, as far as their grape diversity is concerned. That is, grape-vine varietal diversity is relatively evenly distributed among countries, which is a good thing for maintaining diversity.

2. The long edges around the outside of the network indicate that most countries are more different from each other than they are similar. This is interesting, because it means that each country is preserving grape-vine diversity in a somewhat different way. This is not necessarily unexpected, of course, mainly for historical reasons. Moreover, different countries often do have different climates, and therefore different varieties will do well. Also, many countries have chosen to specialize in different varieties, as a wine-making business strategy.

3. There are a few small clusters of countries, which I have highlighted with different colors in the network diagram. For example. clockwise from the bottom:
  • there is a varietal connection between Bulgaria and Romania, which is not unexpected, but also between Bulgaria and China, which you may not have expected;
  • there is quite a close grape-vine connection between the Ukraine and Moldova, and a lesser connection between the Ukraine and Russia;
  • there is a reasonably close varietal connection between Croatia, Slovenia, Slovakia, Czechia, Austria, and Hungary, which presumably reflects the historical Austro-Hungarian Empire (dismantled after World War I), plus a somewhat separate similarity between Croatia and Serbia;
  • there is a varietal association between Thailand and Myanmar, in South-east Asia, plus a more distance (intriguing) connection to Ethiopia;
  • Taiwan and South Korea have a reasonable association of varieties;
  • Armenia and Kazakhstan are closely connected, reflecting the cradle of wine-making, with Georgia being somewhat more distance;
  • there is a small varietal connection between Luxembourg and the United Kingdom, which may reflect a focus on sparkling wines.

4. Then we come to two sets of large but somewhat more complex associations.

First, there are varieties shared among Tunisia, Algeria, and Morocco, reflecting their wine-making tradition as French colonies, supplying warm-climate blending wine to supplement the weaker red wines of France. These countries are then connected to Israel, Mexico, Cyprus, and Turkey, where the same varieties do well. Then there is an intriguing connection of Canada, Japan, Uruguay, and Israel, which bears some looking-into.

Finally, we come to the relationships that we might expect, connecting the varieties of the New World to their origins in Europe. That is, there is an obvious varietal connection between France, Italy, Argentina, South Africa, Chile, Australia, and the United States. However, there is also a separate association between Spain and France, presumably reflecting their shared varieties that have not (yet) become common in New World wine-making.

Note that the grape varieties that are popular in New Zealand are not similar to anywhere else, possibly because of the restricted range of popular varieties. Germany and Switzerland are also disconnected, presumably because most of their varieties have not emigrated.

Below is the network diagram (click to enlarge it). The technical interpretation of this network is described in my post: Summarizing multi-dimensional wine data as graphs, Part 2: networks. Basically, countries that are closely connected along the network edges are similar to each other in terms of their area of the different grape-vine varieties.

Network of which grape-vine varieties grow where

Monday, March 2, 2020

Does the relationship between critics' scores differ by wine type?

A few weeks ago I asked: Are wine scores from different reviewers correlated with each other? I looked at wine-quality scores for two Swedish review sites, Vinbanken and BKWine, and concluded that the answer is “about a half of the time”.

An obvious follow-up question is whether this answer applies to different wine types, or whether there are notable differences between types. This new blog post answers that question — there are definitely detectable differences, in this case.

As for my previous post, the wines come from the Swedish wine chain Systembolaget. These wines are tasted by various media commentators shortly before their release. In my sample, there were 1,034 wines scored by both review sources during 2019. The two critics are not actually in the same room doing the tasting. Both score sources use a 20-point scale.


The first source is from Jack Jakobsson at BKWine Magazine. I deleted the data for beer, cider, saki, fortified wines, and spirits, leaving the reds, whites and rosés. The points are provided in 0.5-point increments. The second source is from Johan Edström at Vinbanken. The scores are reported separately for reds and whites, with rosés included among the whites. The points are usually provided in 0.5-point increments, although occasionally finer divisions appear.

I subdivided the 1,034 wines into four groups: reds (612 wines), whites (319), rosés (37) and sparkling wines (66). For each group, I calculated the average difference in points between the paired scores, as well as the correlation. The difference in average quality scores is shown in the histogram. As you can see, both reviewers award the sparkling wines higher points than the other wine types, followed by the reds, then whites, and finally the rosé wines.

Vinbanken and BKWine quality scores for different wine types.

Also, as I noted last time, the BKWine scores are an average 0.57 points less than the Vinbanken scores. However, this average difference is smaller for the sparkling wines (0.41 points) and red wines (0.47 points) than for the white wines (0.75 points) and rosé wines (1.51 points). Clearly, whites and rosés are downgraded at BKWine, compared to Vinbanken.

The consistent difference among the wine types cannot be disregarded, especially that for the rosé wines, which is significantly less for both reviewers. We cannot expect reviewers to use exactly the same wine-quality scales, but we might at least hope that they are consistent across the various wines that they evaluate.

The possible cause of variation among wine types may not be too hard to detect, as I discussed in the introduction to a previous post (What's all this fuss about red versus white wine quality scores?). Bob Henry commented on my previous post about many non-red wines:
Citing Robert Parker and his 1989 interview with Wine Times magazine (later rebranded Wine Enthusiast), such wines do not improve with age in the bottle. Hence they garner no “bonus” points that place the wine somewhere between 91 points and 100 points. Consequently they bump up against a “glass ceiling” of 90 points.
In this case 90 out of 100 points would be roughly equivalent to 16 or 17 out of 20 points; and this seems to be the fate of the rosé wines, especially. As you can see in the next graph (where each dot represents one or more wines), neither reviewer gave the rosé wines anything like 16 points, even at their best. Furthermore, the Vinbanken scores almost always exceeded the BKWine score for the same wine (the dashed line represents equality).

Vinbanken and BKWine quality scores for rose wine

This does not mean that rosé wines cannot be aged, of course. One classic example is the Fondo Antico “Memorie Rosato”, from Sicily, which is fermented and matured in oak barrels — this wine is not even released until it is 5 years old. Not unexpectedly, it is unlike most other rosés (even the drink-now ones from the same winery); and I can recommend it, if you ever get the chance to try it.

The correlations among the quality scores also differ between the two critics for the different wine types (the numbers represent the amount of the scores that is shared):
Total
Sparkling
Red
White
Rosé
54.5%
75.4%
49.3%
55.5%
13.5%

Clearly, our reviewers agreed much more on the quality of the sparkling wines than they did for the reds and whites; and they had very little agreement at all about the rosé wines (as is obvious in the scatterplot above). So, the rosé wines get short shrift in all ways.

As a final point, these are the three rosé wines that the two reviewers did agree are the best of the selection (represented by the points at the top-right of the scatterplot):
Domaine de la Mordorée “La Reine des Bois” 2018
Marimar Estate “Rosaleda Rosé of Pinot Noir” 2018
Dominio del Águila “Pícaro” 2016
Tavel
Sonoma
Ribera del Duero
$US 25
$US 25
$US 30
These wines still got very poor scores, given that their prices match those of many of the red and white wines.