Risk assessment of banknotes as a fomite of SARS-CoV-2 in cash payment transactions

Abstract

BackgroundThe COVID 19 pandemic has triggered concerns and assumptions globally about transmission of the SARS-CoV-2 virus via cash transactions.ObjectivesAssess the risk of contracting COVID-19 through exposure to SARS-CoV-2 via cash acting as a fomite in payment transactions.MethodsA quantitative microbial risk assessment was conducted for a worst-case scenario assuming an infectious person at the onset of symptoms, when virion concentrations in coughed droplets are at their highest. This person then contaminates a banknote by coughing on it and immediately hands it over to another person, who might then be infected by transferring the virions with a finger from the contaminated banknote to a facial mucous membrane. The scenario considered transfer efficiency of virions on the banknote to fingertips when droplets were still wet and after having dried up and subsequently being touched by finger printing or rubbing the object.ResultsAccounting for the likelihood of the worst-case scenario to occur by considering 1) a local prevalence of 100 COVID-19 cases/100,000 persons, 2) a maximum of about 1/5th of infected persons transmit high virus loads and 3) the numbers of cash transactions/person/day, the risk of contracting COVID-19 via person-to-person cash transactions was estimated to be much lower than once per 39,000 days (107 years) for a single person. In the general populace, there will be a maximum of 2.6 expected cases/100,000 persons/day. The risk for a cashier at an average point of sale was estimated to be much less than once per 430 working days (21 months).DiscussionThe worst-case scenario is a rare event, therefore, for a single person, the risk of contracting COVID-19 via person-to-person cash transactions is very low. At a point of sale, the risk to the cashier proportionally increases but it is still low.

Pandemic payment patterns

“…For example, Tamele et al (2021) report a very low risk of getting the virus via the use of cash. Schijven et al (2021) also find a very low risk. Even in the worst case scenario the risk that a person gets COVID-19 via a person-in-person cash transaction is less than once every 107 years.…”

Stability of pathogens on banknotes and coins: A narrative review

“…SARS-CoV-2 Coins Todt et al 17 ; Schijven et al 23 Banknotes Harbourt et al 15 ; Akter et al 24 ; Todt et al 17 ; Newey et al 25 ; Schijven et al 23 Money cards Newey et al 25 Hepatitis prevent a mass outbreak. 35 Their interaction was brief or through surfaces such as survival equipment subsequently handled by others and did not lead to any downstream positive cases.…”

“…By using actual cash collected from the population, this approach better emulates real‐life scenarios and offers insights into the transmission dynamics between cash and human skin. Nevertheless, current evidence suggests that the chance of pathogen transmission by cash seems very low since not only high viral loads but also a timely order of events is required for successfully transmitting viable virus 23 . Additionally, banknotes, coins and money cards are usually kept protected in wallets and are not continuously exposed to the potentially infectious environment further minimizing the risk of contamination in the first place.…”

“…They assumed the worst-case-scenario to be a rare event making it highly unlikely to contract COVID-19 from paper currency. 23 Overall, while it remains possible for people to be infected through contact with surfaces or objects (fomites) contaminated with SARS-CoV-2, the risk is meanwhile generally considered to be low.…”

“…In agreement with this, Schijven et al used a mathematical approach to estimate the risk of infection through contaminated cash in a worst‐case‐scenario including local SARS‐CoV‐2 prevalence, viral loads of infected individuals and the number of cash transactions. They assumed the worst‐case‐scenario to be a rare event making it highly unlikely to contract COVID‐19 from paper currency 23 . Overall, while it remains possible for people to be infected through contact with surfaces or objects (fomites) contaminated with SARS‐CoV‐2, the risk is meanwhile generally considered to be low.…”