Otun Saha1, Nadira Naznin Rakhi2, Ovinu Kibria Islam1, 3, Md.
Mizanur Rahaman1*
1Department of Microbiology, University of Dhaka,
Dhaka 1000, Bangladesh
2Department of Biotechnology and Genetic Engineering,
Bangabandhu Sheikh Mujibur Rahman Science and Technology University,
Gopalganj, Bangladesh.
3Department of Microbiology, Jashore University of
Science and Technology, Jashore 7408, Bangladesh
*Correspondence: Dr. Md. Mizanur Rahaman, Department of
Microbiology, University Street, Dhaka-1000, Bangladesh.razu002@du.ac.bd; +8801796585290
Dear Editor,
The world is facing the Corona Virus Disease-2019 (COVID-19) pandemic
[1], which is also a highly communicable disease disseminating from
droplet, contact, fecal-oral transmission along with transmission
through fomites [2]. While the frequent handwashing is recommended
for preventing the transmission of SARS-CoV-2 [1], the causative
agent of COVID-19, we might have unseen the importance of avoiding two
prominent vectors of disease transmission: mobile phones and paper
currency. According to a recent survey, the total number of mobile phone
users worldwide is increasing continuously surpassing 4.8 billion
(https://www.statista.com/statistics/274774/forecast-of-mobile-phone-users-worldwide/).
These daily essential accessories can be a potential reservoir for
SARS-CoV-2, as this virus is secreted in saliva, respiratory secretion
and even sweat as well [2]. Considering the threat, Apple, one of
the top mobile manufacturer companies holding 22.4% market share in
2019 has already recommended disinfecting apple products with 70%
alcohol wipe or clorox, which was previously not permitted to protect
the phone’s oleophobic (oil-repellant) and hydrophobic (water-repellent)
coatings. While there has not been any scientific study yet on this
regard, a myriad of microorganisms including nosocomial pathogens has
already been reported from the surface of mobile phones [3]. In a
recent study, SARS-CoV-2 has been claimed to be viable and infectious in
aerosols for hours
(https://www.thehindu.com/sci-tech/health/how-long-does-sars-cov-2-stay-potent/article31259761.ece).
Other studies indicated that, SARS-CoV-2 can remain infectious on
inanimate surfaces for up to nine days at room temperature [2].
Considering these factors, the possibility of spreading COVID-19 from
mobile phones of infected individuals was affirmed by various researcher
and also stated that the virus can remain viable on smartphone screen up
to 96 hours, if it’s made of glass [4]. Furthermore, paper currency
is even more used daily object which changes hands numerous times a day
and can act as potential vector of viral disease transmission.
Previously, human influenza viruses were reported to be viable and
infectious up to 17 days on paper notes [5]. Some In
vitro culture studies also showed that paper currency can harbor high
levels of microbes, some of which are clinically significant in causing
pneumonia and enteric diseases [6]. Similarly, nasal inoculation
particularly with rhinovirus via contaminated fingers was found viable
for long time (2-5days) [4]. Although, this sort of studies have not
been conducted for SARS-CoV-2,considering the possible potential of
paper currency as a vector, World Health Organization (WHO) has advised
taking measures to maintain proper hygiene post handling of notes. After
Covid-19 outbreak, China undertook the disinfection of cash through
ultraviolet light, high temperatures, quarantining it for 14 days etc.
But in many countries, people are not aware of the possible danger of
handling the cash without maintaining proper hygiene. While we have been
focusing on sanitizing and washing our hands countless times a day, most
of us have forgotten the smartphone and banknotes, which in many ways is
a possible reservoir of life threatening viruses. Covert transmission of
COVID-19 through asymptomatic patients [1.2] also indicate the
threat of disseminating the SARS-CoV-2 through these fomites. Although
it has been claimed that, disease transmission from paper notes and
mobile phones may contributes minutely, approximately 1% [2,4], the
transmissibility may vary due to the population density, hygiene
practice and many other factors. But as the paper notes and mobile phone
can be the easiest carrier of communicable diseases, raising awareness
about the transmission from those frequently used inanimate objects
should be encouraged. In conclusion, it is recommended that along with
hand washing and other personal hygiene strategy, appropriate safety
precaution is needed to be taken to limit the risk of spreading Covid-19
from mobile phones and banknotes.