New Book Release: Influenza

“אמר רבי חנינא: הכל בידי שמים חוץ מצנים פחים

Rabbi Chanina taught: Everything is in the hands of heaven, except diseases brought on by cold or heat. ”

— Talmud Bavli, Avodah Zarah 3b

I am delighted to share with you that today Simon and Schuster have released my new book:

Influenza: The Hundred-Year Hunt to Cure the Deadliest Disease in History.

The book is published on the 100th anniversary of the Great Influenza Pandemic, which killed over 675,000 people in the US and 100 million people worldwide. It tells the story of that pandemic, and how our knowledge of, and treatments for influenza have changed over the last century.

Read an excerpt here.

For those of you in Australia, Europe and the UK, the book will be released on January 31, 2019. And good news for our 150+ loyal Chinese readers. The book is being translated and will be released by Social Sciences Academic Press in mainland China in the near future.

Reviews of Influenza

NATURE

We should not underestimate influenza as a serial killer, notes physician Jeremy Brown in this agile study. Brown — director of emergency-care research at the US National Institutes of Health — illuminates much... A thoughtful portrait of an elusive enemy.”

AUDIBLE BEST NEW RELEASES DECEMBER

“Brown, in a casual and accessible style, traces the history of the disease from then until now, revealing…just how much we still don’t understand about this ever-changing virus…Graham Holter’s delivery is upbeat and engaging, complementing the author’s approach towards making this unnerving topic digestible….

SHELF AWARENESS

…an accessible, straightforward and often riveting history of this seasonal menace.... brisk, entertaining and written with an endearing zeal….Influenza is layperson-friendly; Brown's explanations of virology and epidemiology are clearly meant to reach a wide audience of readers.

SCIENTIFIC AMERICAN RECOMMENDED BOOK

…Although we know a lot more about the virus today, which kills 30,000 people in the U.S. annually, we do not know enough to stop the next pandemic. Brown argues that a critical preparatory step should be to place the 1918 pandemic in our collective memory as we have for wars and battles—perhaps with a physical memorial—to honor our losses and to remind us how much there is yet to do.

USA TODAY

Five new books you won’t want to miss this week

“Influenza” by Jeremy Brown (Touchstone, nonfiction, on sale Dec. 18)

What it’s about: On the 100th anniversary of the Spanish flu pandemic of 1918, a physician looks at the history of the virus and where we are today with trying to find a cure.

The buzz: A “no-nonsense account of medicine’s long battle against influenza,” says Publishers Weekly.

Buy on Amazon

Chullin 10a ~ On the Safety of Drinking Snake Venom

חולין י,א

תנן התם ג' משקין אסורין משום גלוי מים ויין וחלב כמה ישהו ויהיו אסורין כדי שיצא הרחש ממקום קרוב וישתה וכמה מקום קרוב א"ר יצחק בריה דרב יהודה כדי שיצא מתחת אוזן כלי וישתה

We learned in a mishna there (Terumot 8:4): Three liquids are forbidden if they were left exposed [ie they were not in a covered container]: Water, wine, and milk. How long shall they remain exposed and their contents will be forbidden? It is a period equivalent to the time necessary so that a snake could emerge from a proximate place and drink. And how far away is considered a proximate place? Rav Yitzḥak, son of Rav Yehuda, said: Even a period equivalent to the time necessary so that a snake could emerge from beneath the handle of the vessel and drink.

We last read about the fear of snakes contaminating water or beer back in October 2017. So let’s take an encore look at two important questions that arise from the Talmud.1) How dangerous is it to drink a liquid that contains snake venom, and 2) do snakes in fact leave venom behind when they drink?

Don't Touch That Beer !

There was a widespread belief was that snakes will drink from liquids left out overnight, (especially when left under the bed) and in doing so would leave fatal venom behind.  In Avodah Zarah 30b Rabbi Yehoshua even categorized three different kinds of liquid contaminated by a thirsty snake:

עבודה זרה ל,ב

שלשה מיני ארס הן של בחור שוקע של בינוני מפעפע ושל זקן צף

There are three kinds of snake venom: that from a juvenile snake sinks; from a middle-aged snake is found in the mid-section of a liquid, and that from an old snake floats on the top.

The Talmud also concluded that a snake would risk its own life to drink from undiluted wine, but is not willing to do so if the wine is diluted. Elsewhere, the Talmud delves into a series of questions about how thoroughly snake venom can infiltrate the lining a water pitcher, and how it will contaminate milk. For this reason (among others) cheese made by idol worshippers is forbidden. Apparently the milk from which the cheese was curdled could be contaminated by the venom in a way that Jewish cheeses were not.

So do snakes really contaminate a liquid from which they are drinking? The answer is no.  Absolutely not. Here is why.

A deep dive into snake venom

בבא קמא קטו, ב

והתניא מים שנתגלו הרי זה לא ישפכם ברשות הרבים ולא יגבל בהן את הטיט ולא ירבץ בהן את הבית ולא ישקה מהם את בהמתו ולא בהמת חבירו

It was taught in a Baraisa: water that was left uncovered should not be spilled out in a public area, nor should one knead clay with it, nor should one lay in the dust with it, nor should one give it to his animal, nor the animal of his friend, to drink. (Bava Kamma 115b)

The rabbis of the Talmud were very worried indeed about the health effects of water that had been left uncovered.  This concern was codified by Maimonides, and later by Ya'akov ben Asher (d. 1340) in his famous halakhic work called the Arba'ah Turim. 

טור יורה דעה הלכות מאכלי עובדי כוכבים סימן קטז 

דברים האסורים משום סכנה
  יש דברים שאסרום חכמים משום סכנה כגון משקין שנתגלו שיש לחוש שמא שתה מהן נחש והטיל בהן ארס אפי' אם שתו מהן אחרים ולא הוזקו אין לשתות מהן  שיש נחש שהארס צף למעלה ויש שארס שלו מפעפע עד אמצעית המשקה  ויש שהארס שלו שוקע לשולי הכלי לפיכך אפי' שתו ממנו אחרים ולא הוזקו אין לשתות מהן דשמא ארס של הנחש ששתה מהן שוקע ואלו המשקין שיש בהן משום גילוי מים יין חלב ודבש ושום כתוש 

Tur, Yoreh De'ah 116. Things that are Prohibited Because they are Dangerous

There are things that the rabbis of the Talmud prohibited because they are dangerous. For example, liquids that were left uncovered, because of the possibility that a snake drank from the water and expelled some of its poison into them. Even if others had drunk from the liquid, and not been injured, one should not drink from them. For some snake venom floats on the surface, and some sinks to the middle and some moves to the edges of the vessel. Therefore, even if others had drunk and had suffered no harm, one should not drink from them, for perhaps the venom from the snake that had drunk the water had sunk to the bottom. The following liquids should not be drunk if they were left overnight in an uncovered vessel: water, wine, milk, honey, and crushed garlic...

The normative Code of Jewish Law, the שולחן ערוך agreed, but added an important caveat:

שולחן ערוך יורה דעה הלכות מאכלי עובדי כוכבים סימן קטז סעיף א 

משקים שנתגלו, אסרום חכמים דחיישינן שמא שתה נחש מהם והטיל בהם ארס. ועכשיו שאין נחשים מצויים בינינו, מותר

The rabbis forbade drinking from liquids that were left uncovered,. They were concerned that a snake may have drunk from them and expelled some of its poison into them. But now that snakes are not commonly encountered, this is permitted. (Shulchan Aruch Yoreh De'ah 116:1)

So today it is permitted for us to drink from an uncovered pot, but only in a place that does not have a problem with poisonous snakes.  Which is not helpful. There are poisonous snakes in nearly every state in the US, resulting in about 2,000 human envenomations each year, and we have noted before that Israel has its own problem with snakes, including the Palestinian Viper.  The World Health Organization estimates that snakes kill between 20,000 and 94,000 people per year. So exactly where this leniency of the Shulchan Aruch might apply is not clear.

But is drinking snake venom indeed dangerous? Nope. In 2012 India Today reported that police in New Delhi had seized about half a liter of snake venom to be used "in high-end raves planned for Valentine's Day in and around the national capital." Apparently the venom, when ingested, produces a euphoric state. Who knew?

Video evidence - Drinking Cobra Venom

It is really hard to find any peer-reviewed scientific studies about people drinking snake venom, because, um, it's a silly thing to do.  But that doesn't mean it hasn't been done. So where could we turn to find people doing silly things? YouTube of course. It involves drinking the venom directly from spitting snake. Apparently, these kind of human interest stories are popular in India. 

Why it is safe to drink snake venom

If you are a diabetic and take insulin, or know someone who does, you may have wondered why the drug has to be injected. It would, after all, be much less bothersome to swallow an insulin pill than to inject insulin several times a day.  The reason is that insulin is a protein, and like all proteins, it is easily broken down by heat and, more importantly, by the acid environment in the stomach.  Our gastrointestinal tracts evolved to break down proteins into their building blocks - and they perform a wonderful job doing precisely that.

Like insulin, snake venom is a complex protein. And so, like insulin, it too is easily broken down in the very acidic environment of your stomach.  Of course, if intact venom gets into your bloodstream, it could kill you. But if you drink venom, then the intact protein never does get into your bloodstream. You don't need to be an Indian snake charmer to safely drink snake venom. You just need a working digestive system.

HOW SNAKES DRINK

In case you were wondering how we know how snakes drink, here is a diagrammatic view of the apparatus used to record the kinematics and water transport during drinking. The video camera was placed to the left. LED, light-emitting diode. From Cundall, D. Drinking in snakes: kinematic cycling and water transport. The Journal of Experimental Biology. 2000; 203, 2171–2185.

The Talmud was concerned that snakes leave venom in water from which they drank, and that a person drinking from that water would then suffer from envenomation. As we have seen, this concern has no biological basis, although theoretically, if there was an open cut or ulcer in the mouth, ingested venom could get into the bloodstream and then cause its havoc.  But there is another reason why the talmudic concern is overstated.  Snakes, you see, don't leave any venom when they drink water.  As you may have noted from watching the first video, it takes a lot to get a snake to expel its venom - like sticking a blue pen in its mouth.  Venom is a snake's most precious commodity, and it has evolved to protect that commodity. Snakes only release venom when they are in danger, or ready to strike their prey, and not otherwise. Want a great example? The venomous rattlesnake. That species has evolved a warning rattle to tell would-be predators that if they get any closer, they will be bitten. This only makes evolutionary sense if it was in the snake's best interest to do everything possible to conserve its venom.

In a fascinating article on how snakes drink published in The Journal of Experimental Biology, David Cundall notes that a snake's tongue does not carry or move water, and that "in many snakes, the tongue does not visibly move during drinking." That leads to the conclusion that snakes are suction drinkers. And that makes them even less likely to leave any venom behind in the water.

“As far as is known, all snakes are suction drinkers, and the only critical structural variations that might be predicted to influence drinking performance are the relative dimensions and shapes of the mandibles and their suspensorial elements and the arrangements of intermandibular muscles and connective tissues.”

— Cundall, D. Drinking in snakes: kinematic cycling and water transport. The Journal of Experimental Biology. 2000; 203, 2171–2185.

So let's put this all together:

1. Snakes don't release their venom unless they are threatened or hunting.

2. Snakes use suction when they drink water. Their mouths are not open, which is needed when they are expelling venom.

3. Snake venom is not dangerous when drunk.

4. (If somehow venom did get into the water, it would be greatly diluted.)

So, there is no danger if you were to drink from water from which a venomous snake had drunk. None. What a relief.

[Partial repost from Bava Kamma 115, Avodah Zarah 30.]

December 4th, Shmuel and the Pope

If you live in Israel, you need not read on.

December 4th is a significant day in the Jewish liturgical calendar. It is the day on which those who live outside Israel begin to add the words ותן טל ומטר - give us dew and rain. Here is the talmudic source for this change:

תענית דף י, א

משנה. בשלשה במרחשון שואלין את הגשמים. רבן גמליאל אומר: בשבעה בו, חמשה עשר יום אחר החג, כדי שיגיע אחרון שבישראל לנהר פרת

גמרא. אמר רבי אלעזר: הלכה כרבן גמליאל. תניא, חנניה אומר: ובגולה עד ששים בתקופה.

Mishnah: On the third of Marcheshvan we ask for rain [that is, we insert the words ותן טל ומטר into the Amidah prayer]. Rabban Gamliel said: it is started on the seventh.

Talmud: Said Rabbi Elazar, the law is like Rabban Gamliel. It was taught in a Beraita: Chaninah said: outside of Israel, it is inserted sixty days after the fall equinox.

This is the only Jewish ritual that is tied to a real solar event. That event is the autumnal equinox, the day on which the sun is directly overhead on the equator, and on which the lengths of day and night are (almost) equal.(Please do not write to tell me about Birkat Hachamah. It is not tied to any real solar or other event anywhere in the cosmos. See here for more details.)

This year the autumnal equinox was on September 22nd (at 9.54am EST to be precise). The Talmud tells us to begin saying ותן טלֹ sixty days later. So you take out the calendar and count. That will bring us to November 21st. But in every siddur with instructions you will read that we start to recite the addition at Maariv on the evening of December 4th. Which is tonight (or was last night if you are reading this in Australia). That’s a full seventy-three days after the equinox. How did that happen?

It is really not difficult to understand, and requires no skill in observational astronomy or non-Euclidian geometry. Here is the explanation in four easy steps.

1. The Julian Calendar

In the Julian calendar the solar year is exactly 365 1/4 days. That is, 365 days plus an additional 6 hours. This is also the length of the year according to the great talmudic sage of the second century, Samuel of Nehardea. And it is the assumed length of the solar year that is still used today in Jewish calculations. The actual length of the tropical year (i.e. one complete cycle of seasons) is slightly shorter: 365 days, 5 hours, 48 minutes and 46 seconds. That’s a difference of less than twelve minutes. Not much you say. And you’d be right, except that over a century that difference adds up to about 3/4 of a day. So every century the Julian calendar (365.25 days) falls behind the actual length of the year by three-quarters of a day.

2. The Gregorian Calendar

Over hundreds of years that difference adds up to many days, which became a real problem for the Church, when Easter was slipping further back in the calendar. The vernal equinox (a real solar event) had fallen on March 21st in the Julian calendar, but over the centuries had slipped back to March 11th. This threw the calculation of Easter into turmoil. To correct this (and other problems) Pope Gregory removed ten days from the calendar. By papal decree, the last day of the Julian calendar was on October 4, 1582. The next day became the first day of the Gregorian calendar, October 15, 1582. Now the spring equinox would fall on March 21, and everyone would be happy.

3. Jewish law stuck to the old Shmuel - Julian calendar

Rather than go along with this change, it was ignored by rabbis of the early modern period. They would rather have been wrong with Shmuel, than right with the Pope. They added back in the ten lost days. But by 1900 an additional three days of slippage had built up. The calendar of Shmuel is now some 13 missing days behind the Gregorian.

4. So add back in the missing days

If you add an additional thirteen days to the sixty days prescribed by the Talmud, you arrive at….December 4th! I told you it was easy. Here, try it for yourself:

Happy December 4th from Talmudology

Chullin 4b~ Circumcision, Shechita, and Hemophilia A

In tomorrow’s page of Talmud, we are deeply engrossed in the question of who is qualified to be a shochet, one who slaughters food in accordance with Jewish law. A baraita (a set of oral teachings that never quite made it into the Mishnah) is quoted that teaches that an uncircumcised man may be a shochet. Then the Talmud asks:

חולין ד, ב

ה"ד אילימא מתו אחיו מחמת מילה האי ישראל מעליא הוא אלא פשיטא מומר לערלות וקא סבר מומר לדבר אחד לא הוי מומר לכל התורה כולה

This uncircumcised man, what are the circumstances? If we say that he is an uncircumcised man whose brothers died due to circumcision and the concern is that he might suffer a similar fate, clearly he may slaughter, as he is a full-fledged Jew and not a transgressor at all. Rather, it is obvious that he is a transgressor with regard to remaining uncircumcised, as he refuses to be circumcised, and the tanna holds that he may nevertheless slaughter an animal since a transgressor concerning one matter is not a transgressor concerning the entire Torah.

The Talmud here is referring to the sad case in which a mother loses her sons because they bleed to death following circumcision. In this encore presentation, let’s revisit the topic, which we first met way back in Yevamot 64a.

יבמות סד, א

תניא מלה הראשון ומת שני ומת שלישי לא תמול דברי רבי רבן שמעון בן גמליאל אומר שלישי תמול רביעי לא תמול... א"ר יוחנן מעשה בארבע אחיות בצפורי שמלה ראשונה ומת שניה ומת שלישית ומת רביעית באת לפני רבן שמעון בן גמליאל אמר לה אל תמולי

It was taught: If she circumcised her first son and he died, and her second son and he too died, she should not circumcise her third son, so taught Rebbi.  Rabbi Shimon ben Gamliel stated that she should indeed circumcise her third child, but [if he died] she must not circumcise her fourth...Rabbi Yochanan said that there was once a case in Zippori in which four sisters had sons:  The first sister circumcised her son and he died, the second sister circumcised her son and he died, the third sister circumcised her son and he died, and the forth sister came to Rabbi Shimon ben Gamliel and he told her "you must not circumcise your son" (Yevamot 64a).

The Talmud here is describing a disease that is affected through the maternal line (hence the four sisters - all of whom seem to pass this disease on to their male children). The disease is X-linked Hemophilia A; the term X-linked indicates that the faulty gene is carried on the X chromosome, which is men is always inherited from the mother. Hemophilia A is an X-linked recessive genetic disease, first described by the American physician John Conrad Otto, who in 1803 described a bleeding disorder that ran in families and mostly affected the men. John Hay from Massachusetts published an account of a "remarkable hemorrhagic disposition" in the New England Journal of Medicine in 1813.

Hay, John. Account of a Remarkable Haemorrhagic Disposition, Existing in Many Individuals of the Same Family. New England Journal of Medicine 1813:2;3;221-225.

 If the mother is a carrier  - as were each of the four sisters in Zippori - then she has a one in four chance of passing on the disease to a child, and that affected child will always be a son:

Courtesy NHLBI

The rabbis argued over a technical point - that is, how many cases of bleeding are needed to establish a pattern. According to Rebbi (that is  Rebbi Yehuda Ha-Nasi, c. 135-217 CE.) two cases were sufficient, while Rabbi Shimon ben Gamliel insisted on three cases before ruling that there was a life threatening pattern.  Indeed the disease in boys must have been very perplexing, because (as you can see in the diagram above) not every boy would be affected. In fact, if the mother is a carrier and the father is not, there is only a 50% chance of a boy having hemophilia.  It is this fact that perhaps explains the dispute between Rebbi and Rabbi Shimon ben Gamliel regarding how many children need to exhibit the disease before we can assume that any future male child will also have it.  If every boy born in the family would have been a hemophiliac, Rabbi Shimon's ruling would have seemed unnecessarily cruel.  But since by chance, half of the boys born might not have hemophilia, the need to demonstrate the prevalence of the disease (in a society in which its genetic foundations were not known) seems eminently sensible.

In  Hemophilia A there are various genetic mutations that result in low levels of clotting factors. These levels may be only mildly decreased, or so low that severe life threatening hemophilia results. It is treated with transfusions of clotting factors which restore the levels to normal. Although these transfusions must be given several times a week in those with severe disease, there is hope that recombinant clotting factors can lengthen the time between the needed transfusions.

The hemophiliac as a shochet

The law discussed in Yevamot that forbids circumcision where there is a family history of hemophilia was certainly practiced. Later in Yevamot, the Mishnah records the case of a priest who was not circumcised -  because of the deaths of his brothers when they underwent the procedure. Tomorrow we read that a man who was not circumcised because he had hemophilia may serve as a shochet. The Talmud records not only the earliest known description of hemophilia, but the emphasis on the preservation of life as a normative Jewish practice.