We started learning since the beginning of the pandemic about the virus, to face the situation. We have learned the following:
1) The
virus is transmitted via aerosol in addition to saliva drops. Why? We
have the story about the chorus rehearsing and apparently keeping the distance between two people. They said: “No one sneezed or coughed.” One-day rehearsal, 60 people practicing, 45
sick, two deaths. https://edition.cnn.com/2020/04/01/us/washington-choir-practice-coronavirus-deaths/index.html This is more anecdotal, if you wish, but
we have other sources of information.
We
have the studies mentioned in the New England Journal of Medicine:
Surgical Masks
Provide Source Control of Respiratory Viruses
Richard T.
Ellison III, MD reviewing Leung NHL et al. Nat Med 2020
Apr 2 Bae S et al. Ann Intern Med 2020 Apr 6
Surgical face masks were
found to reduce presence of influenza and coronavirus RNA in respiratory
droplets and aerosols from infected individuals.
The CDC has just
recommended that the general U.S. population begin wearing cloth face coverings
to decrease the community-based transmission of the SARS-CoV-2 virus. Two new
studies provide some support for the CDC guidelines.
In the first,
researchers at a Hong Kong hospital obtained nasal and throat swabs and
respiratory droplet and aerosol samples from 246 individuals with presumed
symptomatic acute respiratory viral infection seen year-round between March
2013 and May 2016. During a 30-minute collection of exhaled breaths when
patients were breathing and coughing normally, 124 individuals were wearing a
face mask and 122 were not; 49 provided second 30-minute samples of the
alternate type.
By reverse transcriptase
polymerase chain reaction (RT-PCR) there were 54 individuals with rhinovirus
infection, 43 with influenza infection, and 17 with human seasonal coronavirus
infection. For all three viruses, the viral load was higher in nasal than in
oral secretions, and all three viruses were detectable in both respiratory
droplet (particles >5 μm) and aerosol (particles <5 μm) fractions of the
exhaled breath. Masks led to a notable reduction in the number of
RT-PCR–positive respiratory droplet and aerosol samples for patients with
either coronavirus (in respiratory droplets, from 30% to 0%; aerosols, 40% to
0%) or influenza infection (respiratory droplets, 26% to 4%; aerosols, 35% to
22%); there was no meaningful reduction seen with rhinovirus infections.
Influenza virus was able to be grown from 4 of 5 studied RT-PCR–positive
aerosol samples from individuals not wearing masks.
The second study, by Bae
and colleagues, recruited 4 patients with SARS-CoV-2 infection to cough five
times onto petri dishes containing viral transport media approximately 20 cm
from their face while wearing either no mask, a surgical face mask, or a
two-ply cotton mask. The median nasopharyngeal viral load was 5.66 log
copies/mL, and the cough samples found viral loads of 1.4 to 3.5 logs/mL
whether or not a mask was present for three of the four patients. Swabs of the
outer surfaces of both types of masks were positive for all four patients.
COMMENT
The
work by Leung raises the theoretical concern of viral transmission through
aerosols as well as respiratory droplets although, as the authors note, there
was no attempt to grow either coronavirus or rhinovirus from the RT-PCR respiratory
samples to confirm the presence of viable virus. Still, this novel study
provides strong evidence that the use of surgical masks can provide source
control for both human coronavirus and influenza virus infections when
individuals are sitting for 30 minutes. In contrast, the very small study by
Bae shows that neither surgical nor cotton face masks will prevent the spread
of virus from a coughing individual — at least at a distance of only 20 cm.
While both studies have clear limitations, together they suggest that the use
of a surgical face mask can provide some source control in individuals infected
with coronavirus or influenza, although the efficacy is likely diminished in
coughing individuals (and we can't extrapolate the findings to other types of
masks). Still, in my mind these limited data do support the broad use of face
masks until this pandemic is brought under control.
2) The German
expert who instituted the program in Germany challenged the notion that the
virus is primarily acquired touching infected material. The assumption was that the coronavirus is transmitted via air and
not so much by contact.
Researchers
have so far come to different conclusions on how long the virus can survive on
surfaces. But now a team of scientists in Germany are trying to find answers.
"So
far, no transmission of the virus in supermarkets, restaurants or hairdressers
has been proven," explained Bonn virologist Hendrik Streeck on the ZDF
Markus Lanz talk show.
Instead,
the major outbreaks have been the result of close get-togethers over a longer
period of time, he said.
That's
demonstrated in, for example, outbreaks that have stemmed from après-ski
parties in Ischgl, at football matches in Bergamo or at carnival celebrations
in the municipality of Gangelt in the Heinsberg district of North
Rhine-Westphalia.
3) The
lakes, ocean are not infected to the degree of being a source of
infection. The problem is that we still
get aerosol from infected people because those places are crowded most of the
time. The infection is not in the water.
Coronaviruses (CoV) are a large family of viruses that cause
illness ranging from the common cold to more severe diseases. According to WHO,
while persistence in drinking-water is possible, there is no current evidence
that coronaviruses are present in surface or groundwater sources or transmitted
through contaminated drinking-water.
The spread of the virus is closely related to water and
sanitation.Cleaning hands can reduce the transmission and help people stay
healthy but today billions of people lack safe water, sanitation and
handwashing and funding is inadequate.
Based on the above:
1) Keep
your distance, two meters from other human being.
2) Wear
a face mask according to what you do.
Driving a car with other triathletes, wear a N95 mask; use a surgical
mask when riding or running with other mates, keeping most of the time the two meters
of separation.
3) Swim
in an empty swimming pool, one member per lane or in a lake (keeping distance).
4) Wash
your hand as frequently as you can or use gel (alcohol above 60%).
5) Avoid
public places or wear your N95 if you need to be in a close room, even if you
keep the two meters distance (remember the chorus rehearsal).
6) Train
with responsible people that is concerned about his/her health and the health
of others. This is the moment to define
your friends.
7) This
should be in place until we obtain the vaccine or we get 70% infected people. I hope the vaccine comes first.
Regarding your eyes. Wear your glasses like Fauci, but the eyes are not a problem unless you are in very close contact with people:
https://www.researchgate.net/publication/340011892_Role_of_the_Eye_in_Transmitting_Human_Coronavirus_What_We_Know_and_What_We_Do_Not_Know
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