China is disinfecting notes and coins to stop the coronavirus: what we can learn (or not) in the rest of the countries
On January 15, the Chinese Central Bank announced that it was going to start disinfecting huge amounts of the country's cash as part of measures to fight the coronavirus epidemic. We have known for a long time that money can be very dirty: without going any further, a 2017 study found that New York dollar bills contained, on average, 397 different bacterial species rooted on their surface.
However, the Chinese move is surprising because, at least so far, the large campaigns against infectious diseases have not put too much emphasis on this. Is it reasonable to use payment methods that do not require physical contact during epidemics such as influenza or is it an extreme measure? In other words, to what extent is the currency a worrying vector of disease transmission?
Mr money is a powerful gentleman
Can we get it through cash? The question, in fact, has nothing of "crazy idea". After all, successful control of an infectious disease involves identifying the different vectors behind its transmission. In the case of coins, there has usually been little research because copper (and its antimicrobial effects) were assumed to do the dirty cleaning job. But tickets are a separate issue.
In fact, for more than a decade now we have clear evidence that the flu can survive for a long time on a dollar bill. Up to 17 days according to some investigations, although the truth is that in the best circumstances (that is, with respiratory mucus) it is difficult to maintain its ability to infect beyond 48 hours.
Of course, this is all theoretical. It is important to clarify that, although the results of these investigations show a really surprising stability of the virus in "non-biological" environments, at the epidemiological level the impact (if any) seems very small. mainly because the main epidemiological recommendation (washing hands) cuts the transmission either for money or for any other reason.
Furthermore, in recent years, states are not only making an effort to remove banknotes in poor condition from circulation (it is estimated that it costs about 10 billion a year), but they are using less "hospitable" materials for bacteria of all kinds.
What about the coronavirus? In any case, we know that these figures change from virus to virus and many of those we know have similar behavior. What about SARS-CoV-2 (which, let's remember, is the official name of the Wuhan coronavirus)? Although the first data tells that it can survive a few hours in non-biological media, it is not yet known how, or when, or how long. Hence, the Chinese Central Bank of China measure seems disproportionate, but not irrational. The moment we have concrete data, we will see if it was.What are they doing to 'clean the money'? What China is going to do is subject the currency to ultraviolet light (or high temperatures) and then isolate the money for a few weeks before putting it back into circulation. Furthermore, the Central Bank has announced a rather ambitious program to replace all possible money with new money in the coming months.
Should we be careful with bills and coins in our daily life? The truth is that focusing our attention on banknotes can even be counterproductive. It is more advisable to integrate measures such as vaccinating, washing your hands frequently or not rubbing your eyes with dirty fingers in our usual practice. As I said before, these types of practices protect us not only from possible (and unlikely) cash infections, but from many other vectors (most of which are more important than money).
Image | Geronimo Giqueaux