CMAAO CORONA FACTS
and MYTH BUSTER 52
Dr
K K Aggarwal
President
Confederation of Medical Associations of Asia and Oceania, HCFI and Past
National President IMA
549: Should COVID
positive asymptomatic healthcare workers continue working in COVID positive non
critical wards
A:
The new C.D.C. guidelines state
that essential workers who may have been exposed to the virus may
continue to work provided they are asymptomatic, wear a mask at all times for
14 days after their last exposure and have their temperature taken before
entering the workplace.
They must follow C.D.C. guidance on social
distancing, remaining at least 3-6 feet from co-workers and potential new patients.
If they show symptoms, they should be sent home immediately and all surfaces at
the workplace should be cleaned and disinfected.
550: is there any study about COVID virus present
in the shoes
A small study at a hospital in Wuhan, China has found that
COVID-19 could be spread by shoes. The study, published in the Emerging
Infectious Diseases Journal, tested surface samples from an
intensive care unit and general COVID-19 ward at the Huoshenshan Hospital in
Wuhan, China.
The ICU housed 15 patients with severe
symptoms and the general ward housed 24 patients with milder symptoms.
From Feb. 19 through March 2, swab
samples were collected from the floors, computer mice, trash cans, sickbed
handrails, patient masks, personal protective equipment, and air outlets.
The positivity rate was relatively high
for floor swab samples “perhaps because of gravity and air flow causing most
virus droplets to float to the ground. In addition, as medical staff walk
around the ward, the virus can be tracked all over the floor, as indicated by
the 100% rate of positivity from the floor in the pharmacy, where there were no
patients,".
Half of the samples taken from the soles of shoes of ICU medical
workers tested positive, leading health officials to conclude that the shoes
might function as carriers.
The 3 weak positive results from the
floor of dressing room 4 might also arise from these carriers. The study highly
recommend that persons disinfect shoe soles before walking out of wards
containing COVID-19 patients.
Yes. Pool testing involves up to five samples in one go, rather than one at a time. If a pool comes up positive, each sample will be tested individually. This is same we used to do for urine benedicks test for presence of sugar or SSA for urinary proteins when the strips were not available
The ICMR advisory added that the pool testing algorithm involves the Polymerase Chain Reaction (RT-PCR) screening of a specimen pool, comprising multiple samples. In case a pool tests positive, then each sample will be individually tested.
The RT-PCR test is used to determine whether an individual has contracted Covid-19, caused by the SARS-CoV-2 virus. The test is only prescribed to be used in areas with low prevalence of the infection, i.e., with a positivity rate of less than 2 per cent. This means that of 1,000 samples in an area, if less than 20 have tested positive for Covid-19, the area is said to have a low positivity rate, and will qualify for pool testing.
When the disease progresses and probability of positives goes up, the usefulness of the test comes down. One needs to repeat the tests, and conduct all tests individually, if the result is positive.
The objective of pool testing is to increase the capacity of laboratories to screen more samples in the same amount of time without doubling the resources needed. A feasibility study was conducted at ICMR’s Virus Research & Diagnostic Laboratory (VRDL) at King George’s Medical University (KGMU), Lucknow. The study demonstrated that performing real-time PCR testing for Covid-19 with multiple samples (upto five) is feasible when the prevalence rates of infection are low.
Deconvoluted testing (testing individual samples) is recommended if any of the pool is positive. Pooling of more than five samples is not recommended to avoid the effect of dilution leading to false negatives. Preferable number of samples to be pooled is five, but as few as two samples can be pooled. Considering that there is a higher probability of missing a positive sample which has a low viral load, ICMR strongly discouraged pooling more than five samples together, except during research.
Apart from areas with a low prevalence of Covid-19, which will be initially decided based on existing data, the advisory suggests pool testing in areas with positivity of 2-5 per cent. Pooling of samples is not recommended in areas or populations with positivity rates of greater than 5 per cent.
It may also be used for “community survey or surveillance among asymptomatic individuals”, but is strictly prohibited in cases of “individuals with known contact with confirmed cases” and healthcare workers (in direct contact with care of Covid-19 patients). The ICMR highlights that the samples of such high-risk individuals should be “directly tested without pooling”.
552: Healthcare coranxiety
The COVID-19 epidemic is creating legitimate anxiety among healthcare professionals. The epidemic is horrific and any loss of human life is a tragedy.
Robert M. Kaplan, PhD, is a faculty member at Stanford University's Clinical Excellence Research Center, Medpage
In order to investigate this issue, we looked at summaries of physician deaths attributable to COVID-19 through April 10, 2020, in a report published in Medscape. I concentrated on physicians rather than all providers because mortality reports appeared more complete. Through April 10, there were 17 physician deaths in the United States. Sixteen of the 17 deaths occurred among physicians aged 60 or older.
The range in age was 37-92: the only death under age 65 was an oral surgery resident. 65% (11 of 17 deaths) occurred in physicians aged 65 or older and 47% where among those older than 70. Obituaries or press releases were available for 16 of the cases. Although it is uncertain from the write-ups, it appeared that about half of the physicians who died were retired or only practicing part-time. Several of the write-ups noted that the deceased physician had serious health problems, including recurrent cancers.
In order to put the 17 deaths in perspective, I compared the COVID-19 death rate among physicians to that in the general population. There are approximately 1.1 million physicians in the U.S. population of 330 million people. In other words, there is approximately one physician for each 300 persons in the population.
By April 10, there were approximately 20,000 COVID-19 deaths in the US. If physicians are dying at the same rate as people in the general population, we would expect about 66 physician deaths. If the data are accurate, physician deaths are about 75% lower than expected. And, the risk from exposure to sick patients may be an overestimate because in nearly half of cases the physicians appeared to have retired or reduced clinical practice.
Of course, there are concerns about the accuracy of the data. It is possible that the Medscape listing is incomplete. However, each physician COVID-19 death is newsworthy and likely to gain attention. Several Google searches failed to identify additional cases. A second concern is that it was difficult to determine level of current clinical activity from the obituaries. The estimate that half of the cases had retired from clinical practice is hard to validate.
553: Compassionate
use of remdesivir for severe COVID-19
A: In a cohort of patients hospitalised for severe COVID-19 who were
treated with compassionate-use remdesivir, clinical improvement was observed in
36 of 53 (68%) patients, according to a study published in The New
England Journal of Medicine. Specifically, improvement in oxygen-support
status was observed in 68% of patients, and overall mortality was 13% over a
median follow-up of 18 days.
Of the patients administered remdesivir, 64% were receiving invasive
ventilation at baseline, including 8% who were receiving extracorporeal
membrane oxygenation (ECMO). The mortality in this subgroup was 18% compared
with 5.3% in patients receiving non-invasive oxygen support.
554: The Journal of Hospital
Infection study: researchers attempted to disinfect N95 respirators using a
SteraMist Binary Ionization Technology.
Yes: The main constituent contains 7.8% H2O2 solution which converts to
ionized H2O2 (iHP) vapour after passing through a cold plasma arc, and moving
like a gas throughout the surface of N95 respirator. The by-product of iHP is
oxygen and water in form of humidity.
555: Journal of Microbiology,
Immunology and Infection: showed persistent shedding of COVID 19 virus in
stools of infected children
Yu-Han Xing, MD, the Chinese University of Hong Kong, Hong Kong, China,
and colleagues analysed data from 3 children with COVID-19 in Qingdao, Shandong
Province, China. Patients were followed-up to March 10, 2020. Clearance of
SARS-CoV-2 in respiratory tract occurred within 2 weeks after abatement of
fever, whereas viral RNA remained detectable in stools of paediatric patients
for longer than 4 weeks. Two children had fecal SARS-CoV-2 undetectable 20 days
after throat swabs showing negative, while that of another child lagged behind
for 8 days.
SARS-CoV-2 may exist in children’s gastrointestinal tract for a longer
time than respiratory system.
None of the children developed severe complications nor required
intensive care or mechanical ventilation. All 3 children only presented with
fever and mild cough or with no obvious symptom but non-typical radiological
abnormalities, and all children showed increased lymphocytes. All children
showed good response to anti-viral and supportive treatment including
inhalation of interferon and oral ribavirin.
556: How common are GI
symptoms
New research out of China shows that a minority of cases appear with
gastrointestinal symptoms only. In about one-quarter of patients in the new
study, diarrhea and other digestive symptoms were the only symptoms seen in
mild COVID-19 cases, and those patients sought medical care later than those
with respiratory symptoms. "Failure to recognize these patients early and
often may lead to unwitting spread of the disease among outpatients with mild
illness, who remain undiagnosed and unaware of their potential to infect
others," said a team from Union Hospital and Tongji Medical College in
Wuhan, China, the original epicenter of the coronavirus pandemic.
557: CDC: Coronavirus
Can Spread 13 Feet, Cling to Shoes
558: Do we
know the prevalence of COVOD 19 in the society
A new study has begun recruiting at the
National Institutes of Health in Bethesda, Maryland to determine how many
adults in the United States without a confirmed history of infection with
SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), have
antibodies to the virus. The presence of antibodies in the blood indicates a
prior infection. In this “serosurvey,” researchers will collect and analyze
blood samples from as many as 10,000 volunteers to provide critical data for
epidemiological models. The results will help illuminate the extent to which
the novel coronavirus has spread undetected in the United States and provide
insights into which communities and populations are most affected.
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