CMAAO
CORONA FACTS and MYTH BUSTER 76
Dr K K Aggarwal
President Confederation of Medical
Associations of Asia and Oceania, HCFI and Past National President IMA
With regular inputs from Dr Monica Vasudev
781: Pot lockdown surveillance
A far-reaching
surveillance initiative was implemented in Shenzhen, China, to isolate and
contact trace people suspected of having the COVID-19 coronavirus. This
initiative led to faster confirmation of new cases and reduced the window of
time during which people were infectious in the community. This potentially
reduced the number of new infections that arose from each case, according to a
study of patients and contacts over 4 weeks (Lancet Infect Dis. 2020 Apr 27.
doi: 10.1016/S1473-3099[20]30287-5).
782: Cases of large-vessel stroke in young
patients with COVID-19
According to a study published in The New England
Journal of Medicine, large-vessel stroke may be another complication of
COVID-19. Over a 2-week period from March 23 to April 7, 2020, a total of 5
patients who were younger than 50 years of age presented with new-onset
symptoms of large-vessel ischaemic stroke, wrote Thomas J. Oxley, MD, Mount
Sinai Health System, New York, New York. All 5 patients tested positive for
COVID-19. By comparison, every 2 weeks over the previous 12 months, our service
has treated, on average, 0.73 patients younger than 50 years of age with
large-vessel stroke.
All patients presented with signs and symptoms of stroke, including
reduced level of consciousness, hemiplegia, and dysarthria. Patients 1, 4, and
5 had COVID-19 symptoms, including cough, fever, and lethargy. Two patients in
our series delayed calling an ambulance because they were concerned about going
to a hospital during the pandemic.
783: A study, published in Clinical Infectious
Diseases, showed that the majority of patients with SARS-CoV-2 developed
robust antibody responses between 17 and 23 days after illness onset, with
delayed but stronger antibody responses in critical patients.
Jiuxin Qu, MD, Third People’s Hospital of Shenzhen, Shenzhen, China, and
colleagues analysed data from 41 patients with confirmed SARS-CoV-2 (two
back-to-back tests). Patients with mild, moderate, and severe disease were
included. IgG and IgM antibodies against SARS-CoV-2 were measured using
the iFlash-SARSCoV-2 IgG/IgM chemiluminescent immunoassay kit. According to the
instructions, the sensitivity and specificity of the kits was 90% and 95% for
IgG, and 80% and 95% for IgM. Combined nucleocapsid protein and spike
glycoprotein were used as coated antigens to increase the sensitivity.
Of the 41 patients, 40 (97.6%) of patients (40/41) were positive with
IgG and 36 (87.8%) were positive with IgM. The median time of seroconversion
after disease onset was 11 days for IgG and 14 days for IgM. The level of
IgG antibody reached the highest concentration on day 30, while the highest
concentration of IgM antibody appeared on day 18, but then began to decline.
Although the IgG level of those in the mild and moderate group was still
rising on day 28, the IgG response of the critical group was significantly
stronger than that of non-critical groups within 4 weeks after illness onset (P =
0.0001). For IgM, the fitting curve of the critical group rose above the
cut-off value on day 10, peaked on day 23, and then began to decline. However,
the IgM levels of non-critical groups rose above the cut-off value as early as
day 5, peaked on day 16, and then decreased.
In the majority of the patients, there were antibody responses to
SARS-CoV-2 during the first 3 weeks of the disease. The seroconversion time of
IgG antibody was earlier than that of IgM antibody. The kinetics of
anti-SARS-CoV-2 antibodies should be helpful in epidemiologic surveys, and
especially in clinical diagnoses since the immunoassays can efficiently compensate
the false negative limitations of nucleic acid testing. SOURCE: The New England
Journal of Medicine and Clinical Infectious Diseases
783: Viral Shedding Continues Up to 6
Weeks After Coronavirus Symptom Onset
Patients may continue to shed the SARS-CoV-2 virus for up to six weeks
after symptoms emerge, a small study of recovered COVID-19 patients suggests. In
the convalescence period, a trace of virus may still be detected however,
similar to other virus infections, this is not indicative of the transmission
ability of the infected individual.
As reported in Clinical Infectious Diseases, 299 RT-PCR assays were
performed (about five tests per patient). The longest duration between symptom
onset and an RT-PCR test was 42 days, whereas the median duration was 24 days. In
the first three weeks after symptom onset, the majority of RT-PCR results were
positive for SARS-CoV-2. From week three onward, negative results increased.
All tests were negative at week six after symptom onset. The rate of positive
results was highest at week one (100%), followed by 89.3%, 66.1%, 32.1%, 5.4%
and 0% at weeks two, three, four, five and six, respectively.
784: What is prolonged shedding
Is nucleic acid conversion time more than 24 days
785: What is the risk factor for
prolonged shedding
Patients with longer viral shedding tended to be older and were more
likely to have comorbidities such as diabetes and hypertension.
From a public health perspective, he added, "I need to emphasize
that the public should not be scared by those seemingly 'prolonged' positive
cases. It is way harder to prove 'no transmission ability' than 'potentially
transmissible.'"
786: What does 14 days isolation means
People need to realize that a
14-day isolation is appropriate for seeing whether one will develop symptoms
after a known exposure to an infected person. Fourteen days is not a sufficient
amount of time to be infected, recover and then be virus free.
787: What is the HCW return policy
Dr. Robert Quigley, Senior Vice President and Regional Medical Director
of International SOS, noted in an email to Reuters Health, "The question
that remains is how great does the viral load need to be to infect another
person if in fact the viral load actually decreases over time. Regardless,
until this virologic feature is defined, it is clear that infected healthcare
professionals (HCPs) should have two consecutive negative tests before
returning to the healthcare arena where they could potentially infect a fragile
patient."
788: When should non-HCPs return to the workplace after testing positive
for COVID-19
The absence of symptoms may not eliminate the risk of transmission to
co-workers for up to 42 days post the onset of symptoms. Such conclusions could
clearly impact our present practices of quarantine and isolation. [SOURCE:
https://bit.ly/358QIJc Clinical Infectious Diseases, online April 19,
2020.Deaths]
789: Confirmation of COVID-19 in Two Pet
Cats in New York
U.S. Centers for Disease Control and Prevention (CDC) and the United
States Department of Agriculture’s (USDA) National Veterinary Services
Laboratories (NVSL) announced the first confirmed cases of SARS-CoV-2 (the
virus that causes COVID-19) infection in two pet cats. These are the
first pets in the United States to test positive for SARS-CoV-2.
The cats live in two separate areas of New York state. Both had mild
respiratory illness and are expected to make a full recovery. SARS-CoV-2
infections have been reported in very few animals worldwide, mostly in those
that had close contact with a person with COVID-19.
At this time, routine testing of animals is not recommended. Should
other animals be confirmed positive for SARS-CoV-2 in the United States, USDA
will post the findings. State animal health and public health officials
will take the lead in making determinations about whether animals should be
tested for SARS-CoV-2.
· In
the NY cases announced today, a veterinarian tested the first cat after it
showed mild respiratory signs. No individuals in the household were confirmed
to be ill with COVID-19. The virus may have been transmitted to this cat by
mildly ill or asymptomatic household members or through contact with an
infected person outside its home.
· Samples
from the second cat were taken after it showed signs of respiratory illness.
The owner of the cat tested positive for COVID-19 prior to the cat showing signs.
Another cat in the household has shown no signs of illness.
Both cats tested presumptive positive for SARS-CoV-2 at a private
veterinary laboratory, which then reported the results to state and federal
officials. The confirmatory testing was conducted at NVSL and included
collection of additional samples.
The World Organisation for Animal Health (OIE) considers SARS-CoV-2 an
emerging disease, and therefore USDA must report confirmed U.S. animal
infections to the OIE.
Public health officials are still learning about SARS-CoV-2, but there
is no evidence that pets play a role in spreading the virus in the United
States. Therefore, there is no justification in taking measures against
companion animals that may compromise their welfare. Further studies are needed
to understand if and how different animals, including pets, could be affected.
Until we know more, CDC recommends the following:
· Do
not let pets interact with people or other animals outside the household.
· Keep
cats indoors when possible to prevent them from interacting with other animals
or people.
· Walk
dogs on a leash, maintaining at least 6 feet from other people and animals.
· Avoid
dog parks or public places where a large number of people and dogs gather.
If you are sick with COVID-19 (either suspected or confirmed by
a test), restrict contact with your pets and other animals, just like you would
around other people.
· When
possible, have another member of your household care for your pets while you
are sick.
· Avoid
contact with your pet, including petting, snuggling, being kissed or licked,
and sharing food or bedding.
· If
you must care for your pet or be around animals while you are sick, wear a
cloth face covering and wash your hands before and after you interact with
them.
