and challenges to the community as well as the healthcare
system. In response to this unprecedented outbreak, which
had already produced a higher number of infected case and
mortality as compared with outbreak of SARS-CoV in 2003
within the first six weeks of its declaration, a rapid infection
control response is essential to contain and mitigate the risk
of nosocomial transmission and outbreak. With reference to
experience in the outbreak of SARS-CoV, almost 60 percent
of nosocomial acquisition of SARS-CoV was HCWs, it is
critically important to implement proactive infection control
measures, which must be planned ahead.”
The researchers say they enhanced the infection
control measures at their institution by implementation of
standard, contact, droplet, and airborne precautions for
suspected or confirmed cases. “We stepped up the use
of PPE among HCWs in performing aerosol generating
procedures (AGPs), even when caring for patients without
clinical features and epidemiological exposure risk in the
general wards. Performance of AGPs such as endotracheal
intubation, open suctioning, and use of high flow oxygen
had been shown to be associated with the risk factors for
nosocomial transmission of SARS-CoV among HCWs. In
addition, provision of surgical masks to all HCWs, patients,
and visitors in clinical areas was implemented since day
5. Although wearing surgical masks alone was not clearly
associated with protection of person from acquisition of
SARS-CoV, wearing surgical masks by either HCWs or patients
had shown to reduce the risk of nosocomial transmission of
influenza pandemic. The combination of hand hygiene with
facemasks was found to have statistically significant efficacy
against laboratory-confirmed influenza in the community as
illustrated in a systematic review and meta-analysis. Hand
hygiene among HCWs and patients was promoted and
enforced during the epidemic of SARS-CoV-2. With all these
measures, we could maintain zero nosocomial transmission
of SARS-CoV-2 since the importation of first confirmed case
since day 22 in Hong Kong.”
The researchers add, “With the implementation of active
and enhanced surveillance with progressive widening of
screening criteria during the evolution of epidemic, we could
recognize most of the confirmed cases upon hospitalization
and achieved zero nosocomial transmission in HCWs and
patients within the first six weeks. However, our surveillance
program may be challenged by patients with mild symptoms.
In the early publications, fever and cough were reported in
87 percent and 80 percent of patients, respectively, at the
time of presentation. With the presence of locally acquired
cases, epidemiological criteria may no longer be useful for
admission screening. Vigilance in hand hygiene practice,
wearing of surgical masks in the hospital, and appropriate
use of PPE in patient care, especially performing AGPs, are
the key infection control measures to prevent nosocomial
transmission of SARS-CoV-2 even before the availability of
effective antiviral agents and a vaccine.”
To summarize, the researchers, from Queen Mary Hospital
in Hong Kong, reported that zero healthcare workers con-
tracted COVID-19 and no hospital-acquired infections were
identified after the first six weeks of the outbreak, even as
the health system tested 1,275 suspected cases and treated
42 active confirmed cases of COVID-19. Eleven healthcare
22
workers, out of 413 involved in treating confirmed cases,
had unprotected exposure and were quarantined for 14
days. None became ill.
“Appropriate hospital infection control measures can
prevent healthcare-associated transmission of the coronavi-
rus,” study authors say. “Vigilance in hand-hygiene practice,
wearing of surgical masks in the hospital, and appropriate use
of personal protective equipment in patient care, especially
when performing aerosol-generating procedures, are the key
infection control measures to prevent
hospital transmission of the virus.”
Researchers also conducted an
experiment taking air samples from In response to
close to the mouth of a patient with this unprecedented
a moderate level of viral load of coro-
outbreak, which had
navirus. The virus was not detected in
any of the tests, whether the patient already produced
was breathing normally, breathing
a higher number
heavily, speaking or coughing, and
of infected case
tests of the objects around the room
detected the virus in just one location,
and mortality as
on a window bench.
“The descriptive study employed compared with
unique environmental and air samples
outbreak of
with the results suggesting that environ-
mental transmission may play less of a SARS-CoV in
role than person to person transmission
2003 within the
in disease propagation,” says Gonzalo
first six weeks of
Bearman, MD, professor of medicine
and chair of the Division of Infectious
its declaration,
Disease at Virginia Commonwealth
a rapid infection
University, who reviewed but was not
involved in the study.
control response is
When the first reports of a cluster of
essential to contain
pneumonia cases came from Wuhan,
and mitigate the
Hong Kong’s 43 public hospitals
stepped up infection control measures risk of nosocomial
by widening screening criteria to
include factors like visits to hospitals in transmission and
mainland China. When the screening
outbreak.”
process identified a patient infected
with the coronavirus, the patient was
immediately isolated in an airborne infection isolation room
or, in a few cases, in a ward with at least a meter of space
between patients.
Enhanced infection control measures were put in place
in each hospital, including training on the use of personal
protective equipment, staff forums on infection control,
face-to-face education sessions, and regular hand-hygiene
compliance assessments. Hospitals also increased the use
of personal protective equipment for healthcare workers
performing aerosol generating procedures like endotracheal
intubation or open suctioning for all patients, not just those
with or at risk for COVID-19.
During the first six weeks of the outbreak, the number
of locally acquired cases of COVID-19 in Hong Kong
increased from 1 of 13 cases confirmed in the first 32 days
of surveillance to 27 of 29 cases confirmed from day 33 to
42. Of the locally acquired cases, 28 came from eight family
clusters with 11 cases likely transmitted during a gathering
april 2020 • www.healthcarehygienemagazine.com