Blog Article – Thursday 27th Feb 2020
Human Coronaviruses are able to survive on commonly-touched surfaces
Infectious disease is characterised by the ability of the causative agent, the pathogen, to spread within a population. Some pathogens appear to spread remarkably efficiently between individuals whereas others demonstrate reluctance to disseminate. A key area of microbiological research aims to understand why pathogenic microbes behave like this but the task is complicated because of the potential contribution of diverse factors like the genetics of the pathogen and host and the survivability of the pathogen outside its host.
The emergence of a previously unrecognised infectious disease (and the revealing of the pathogen causing the infection) obviously requires the question of how the pathogen spreads to be addressed. In the case of the human coronavirus designated, COVID-2019, public health officials have focused on containing the spread of the virus so an understanding of modes of transmission of this coronavirus is crucial in order to apply effective intervention measures. A key aspect of the spread of pathogens is wrapped up in their ability to survive outside their hosts. Any pathogen that survives in the environment (think of commonly touched inanimate surfaces shared by communities of people that have been contaminated with the pathogen) and remains infectious is probably capable of causing more infections. When coronavirus is not infecting a person, where is it and what is it doing? Is coronavirus capable of producing more human disease through self-infection from contaminated surfaces?
A scientific paper appearing recently in the Journal of Hospital Infection (1) has reviewed a collection of existing publications studying the survival of coronaviruses in the environment. The emergence and spread of COVID-2019 warrants the pooling and re-evaluation of what we know already about coronaviruses. An immediate limitation of this review was that only coronaviruses available for research have been described – COVID-2019 is not (yet) available to the wider scientific community. However, microbiologists usually allow for knowledge transfer between sufficiently related microbes. That means empirically-based inference is often adequate and so we can consider how COVID-2019 behaves according to observations of other coronaviruses. So, what does the review say about the survival of coronaviruses of inanimate surfaces?
The review present data showing that human and animal coronaviruses survive for extended periods of time on inanimate surfaces. The picture is complicated by necessarily considering parameters like temperature, humidity and number of viral particles, but the take home message of survivability of human coronaviruses on inanimate surfaces is that they remain active for up to 5 days on metal (a), 5 days on paper (b) and up to 9 days on plastic (c). When restricting observations to surfaces held at room temperature, human coronaviruses were seen to remain active for even longer, up to 9 days. The potential of self-infecting (by picking up virus from a contaminated surface and inoculating one’s self) is apparent.
The World Health Authority, referring to the prevention of spread of the novel human coronavirus, recommends that ‘environmental cleaning and disinfection procedures are followed consistently and correctly.’ (2) The sole function of surface disinfection is to reduce the contribution of the environment, specifically inanimate surfaces, to the incidence of infectious disease.
1. Persistence of coronaviruses on inanimate surfaces and their inactivation with biocidal agents. Kampf, G., et al., Journal of Hospital Infection, Feb., 6, 2020 (In press). www.journalofhospitalinfection.com/article/S0195-6701(20)30046-3/fulltext
2. WHO. Infection prevention and control during health care when novel coronavirus (nCoV) infection is suspected. WHO; 2020. Interim guidance. 25 January 2020.
a) Human Coronavirus (HCoV) Strain 229E and Severe Acute Respiratory Syndrome (SARS) Coronavirus Strain P9
b) SARS Coronavirus Strain P9
c) SARS Coronavirus Strain FFM1
Dr Richard Hastings (Mirius Healthcare Regulatory & Technical Manager)- 27/2/2020.
About – Dr Richard Hastings – Richard has a Phd in Microbiology with many years’ experience in biocides. He is highly skilled in REACH, BPR and registration issues for biocides on a global scale having develop new products and gained registration and acceptance of these products all over the world. He has established research and is a published author in antimicrobial technology.