Technical
Droplet infection occurs through the air, for example
through the breathing, speaking, sneezing or coughing of a
sick person. When this happens, thousands of small droplets
are released into the ambient air. Within split seconds, they
shrink by 90% of their volume and adapt to the ambient
conditions. At this point, it is important that the ambient
air humidity is right so that the saline solution does not
get oversaturated and crystallisation does not occur. Thus,
the droplet remains moist and the disease-causing agents
it contains become inactive within a short period of time.
Otherwise, a tiny, floatable droplet encased in a salty crust
is formed. The saline solution within this crust would be an
environment in which viruses and bacteria can survive. These
structures are so light that they float around like invisible
spaceships in search of another host in order to penetrate its
cells. And this happens at home, in the office, in the doctor’s
practice, or in a hospital.
Breathing in excessively dry air
compromises the functioning of the
respiratory epithelium.
If healthy people inhale infected atmospheric air or come in
direct contact with infectious people, the highest alert level
is necessary. This is because whenever anybody inhales these
contaminated aerosol droplets via his or her moist airways,
the salty crust dissolves immediately on contact with the
persons’ body fluids. This gives viruses the chances to
penetrate cells of the body and cause an infection. However,
we now know that especially viruses, which cause many
infections especially in winter, cannot withstand moderately
moist air of 40 to 60% humidity and within a few minutes no
longer pose a threat. And when you think that we spend the
majority of our lifetimes in buildings, you realise that we also
share the air we breathe with all those in the same place. So,
we can conclude that the air we breathe is our main means
of contact, although we don’t know what it contains at any
point in time.
Lifespan of viruses: Viruses are our constant companions.
We come in contact with them on a daily basis without
getting sick. They stick to objects and can get into the body
through contact with our hands. In most cases, a healthy
immune system kills them off — usually without us even
noticing. Unlike bacteria, viruses are not living things. In
simple terms, they consist of genetic material within a
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RACA Journal I January 2019
shell. They cannot reproduce themselves. For this reason,
they need a host cell in which they implant their genetic
information and which they reprogram and can then
reproduce themselves. The healthy cell is destroyed in the
process. If our immune system is weakened, we get sick.
Outside of their host, viruses generally remain effective
only for a few seconds. It depends to a large extent on the
temperatures and the air humidity. They dislike warmer
conditions above 20°C as much as they do a relative air
humidity between 40 and 60%. On the contrary, low
temperatures and particularly a low air humidity offer ideal
atmospheric conditions for the viruses themselves or for
aerosols occupied by viruses to remain active over the course
of several days.
Brain: Our cerebrum and cerebellum make up only 2% of
the body. Nevertheless, we need 20% of our blood for a
sufficient oxygen supply alone. Brain cells consist of 85%
water. The majority of the energy needed for thinking is
generated there through a hydroelectric process. This is why,
after a certain length of time, a lack of water in the body
means that too little energy is available to us. As a result,
many vital functions are suppressed. A low energy level in
turn means that physical and mental tasks can hardly be
completed over longer periods of time.
Eyes: Our eyes are supplied with nutrients and oxygen
through the tear film. In addition, bodily substances with
disinfectant properties for defence against viruses and
bacteria are transported or foreign bodies washed off. To
do this, our eyelids wipe the eyes every four to six seconds,
before the existing tear film breaks down.
If the formation of tears is impeded however, or their
composition is no longer correct, the tear film gets stripped
away despite the closing of the lids. Dry patches occur on
the eye, which lead to itchiness or even infections. Eye drops
provide only short-term relief and are therefore not a long-
term solution.
Immune defence: Our immune defence truly is a marvel. It
protects a healthy body from the infiltration of viruses, bacteria
and other undesirable particles or germs in a natural way.
Above all, our noses are called on to do this work. Breathing
occurs mainly through our organ of smell. We breathe in mostly
through the nose and, especially when talking, out through the
mouth. Via the airways, our ambient air sweeps into the lungs
and into the tiniest end-organs, the alveoli.
The entire way there is coated with mucous membranes,
which excrete a fluid on a continuous basis. Part of it has
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