#14,786
Despite the inevitable eye-rolling that comes whenever public health officials recommend hand-washing and/or hand sanitizing during flu season, it is actually good advice. Viruses can cling to inanimate objects or surfaces (fomites), and survive (depending upon environmental conditions) for hours.
Hand hygiene alone won't protect you from the flu, but it does cut down on the potential ways you can become infected. And as part of a `layered' strategy, can help reduce your odds of becoming ill.While there are still a great many unknowns surrounding the transmission of 2019-nCoV, some of what we learned about SARS transmission 17 years ago - along with a NEJM study published yesterday - suggest that hand hygiene may end up playing an important role in preventing infection as well.
First, a quick look at the NEJM study, which follows the clinical course and treatment of the first imported 2019-nCoV case into the United States. I've provided the link below, and you'll want to read it in its entirety, but I'll draw your attention to one specific finding.
First Case of 2019 Novel Coronavirus in the United States
Michelle L. Holshue, M.P.H., Chas DeBolt, M.P.H., Scott Lindquist, M.D., Kathy H. Lofy, M.D., John Wiesman, Dr.P.H., Hollianne Bruce, M.P.H., Christopher Spitters, M.D., Keith Ericson, P.A.-C., Sara Wilkerson, M.N., Ahmet Tural, M.D., George Diaz, M.D., Amanda Cohn, M.D., et al.,for the Washington State 2019-nCoV Case Investigation Team*
January 31, 2020(Excerpt)
DOI: 10.1056/NEJMoa2001191
On days 2 through 5 of hospitalization (days 6 through 9 of illness), the patient’s vital signs remained largely stable, apart from the development of intermittent fevers accompanied by periods of tachycardia (Figure 2). The patient continued to report a nonproductive cough and appeared fatigued.
On the afternoon of hospital day 2, the patient passed a loose bowel movement and reported abdominal discomfort. A second episode of loose stool was reported overnight; a sample of this stool was collected for rRT-PCR testing, along with additional respiratory specimens (nasopharyngeal and oropharyngeal) and serum. The stool and both respiratory specimens later tested positive by rRT-PCR for 2019-nCoV, whereas the serum remained negative.(SNIP)
Detection of 2019-nCoV RNA in specimens from the upper respiratory tract with low Ct values on day 4 and day 7 of illness is suggestive of high viral loads and potential for transmissibility. It is notable that we also detected 2019-nCoV RNA in a stool specimen collected on day 7 of the patient’s illness. Although serum specimens from our case patient were repeatedly negative for 2019-nCoV, viral RNA has been detected in blood in severely ill patients in China.4 However, extrapulmonary detection of viral RNA does not necessarily mean that infectious virus is present, and the clinical significance of the detection of viral RNA outside the respiratory tract is unknown at this time.(Continue . . . )
By itself, hardly definitive. But the experience with SARS in 2003 suggests that the fecal-oral route may have been responsible for a significant amount of viral transmission, particularly at the Amoy Gardens Apartment in Hong Kong where 330+ residents were infected.
A 2006 review found:
Environmental transmission of SARS at Amoy Gardens.
McKinney KR1, Gong YY, Lewis TG.
Abstract
Recent investigations into the March 2003 outbreak of SARS in Hong Kong have concluded that environmental factors played an important role in the transmission of the disease. These studies have focused on a particular outbreak event, the rapid spread of SARS throughout Amoy Gardens, a large, private apartment complex. They have demonstrated that, unlike a typical viral outbreak that is spread through person-to-person contact, the SARS virus in this case was spread primarily through the air.
High concentrations of viral aerosols in building plumbing were drawn into apartment bathrooms through floor drains. The initial exposures occurred in these bathrooms. The virus-laden air was then transported by prevailing winds to adjacent buildings at Amoy Gardens, where additional exposures occurred. This article reviews the results of the investigations and provides recommendations for maintenance and other measures that building owners can take to help prevent environmental transmission of SARS and other flulike viruses in their buildings.
While the plumbing system of Amoy Gardens was faulty, we've seen evidence that `toilet plumes' can potentially aerosolize viruses (see Toilet Bowl Sunday and NIOSH Video: Adventures In Toilet Plume Research) and distribute them through the air.
And anyone who has witnessed a norovirus outbreak at a school, or on a cruise ship, can attest to the effectiveness of transmission via the fecal-oral route.The CDC's (archived) Severe Acute Respiratory Syndrome (SARS) website (updated May, 2005) has this to say about the transmission of SARS.
Transmission of SARS-CoV appears to occur predominantly through close interactions with infected persons. Infectious respiratory secretions are the most likely source of infection, although fecal/oral transmission may have occurred in some settings.
Contact with contaminated body substances, either directly (e.g., shaking hands) or indirectly (e.g., touching objects contaminated with respiratory secretions or stool), can lead to exposure. SARS-CoV may also be transmitted through close contact with respiratory droplets expelled when a patient coughs or sneezes. In some instances, however, true airborne transmission (i.e., via droplet nuclei) cannot be excluded as a possible mode of SARS-CoV transmission.Overnight Jason Gale, one of a handful of truly reliable science reporters working in mainstream media, published an article on Bloomberg (link below), which explores the possibility of 2019-nCoV being spread by the fecal-oral route.
It's a good read, so follow the link to read it in its entirety.
Coronavirus Lurking in Feces May Reveal Hidden Risk of Spread
By Jason Gale
February 1, 2020, 1:55 AM EST
- Squat latrines, common in China, may be a virus source
- 2019-nCoV virus was found in loose stool of case in Washington
While we are a long way from pinning down the significance of the fecal-oral spread of this novel coronavirus, the simple advice to wash (or sanitize) your hands frequently is an easy, and reasonable protective measure to take, and very much worth following (see The WHO NPI Guidance : Personal Protection).
A couple of days ago, in WHO Interim Advice On The Community, Home, Healthcare Use of Masks For nCoV2019s, I wrote:
I'll use my small stash of surgical masks and N95s in my role as a `flu buddy' to friends and neighbors, or to wear if I'm infected to protect others. I might even slip a surgical mask on if I found myself stuck in a large crowd, but I certainly wouldn't expect much from it.
What I have stocked up on, and is still widely available, is hand sanitizer. And while it may offer very limited protection - I use it generously during every flu season - and will do so if and when nCoV2019 becomes a significant threat.Like N95s and surgical masks, hand sanitizer may become harder to find on store shelves in the days and weeks ahead, so you may want to pick up some now, while you can.
