Architect Dr. Ami Ran
In order to understand the connection between the Corona pandemic and architecture, one must first sharpen the difference between germ and virus. While a germ is an autonomous live cell, a virus is a parasite that cannot exist without a hosting cell in order to use its protein to build a protective envelope. However, the fact that they can move, reproduce though a Pilus - a kind of sexual organ, certainly negates the mistaken belief that a virus is not an organic creature.
Problematic viruses such as HIV, Papilloma and Corona – have a double layered Capsid - a kind of protective vest of the virus’s sensitive RNA - genetic material made of a single-fiber helix. Approximately 50% of the capsid is made of amphipathic molecules, lipid, (a main component in all biological cell membranes), cholesterol and glycoproteins, by which the virus manages to deceive the hosting cell receptors in order to penetrate it.
One of the challenges of the research striving to develop vaccines or antibodies stems from the pace at which the virus’ genetic changes take place, when two viruses penetrate the same hosting cell, exchange genetic information, and actually create a new kind of virus.
Viruses are usually able to infect only a particular kind of animal. Thus, dogs are not infected by influenza, and humans are not at risk from FIV, the cat AIDS virus. The problem is that while exchanging genetic information, viruses might acquire receptors that facilitate interaction with various types of animals. A virus (or bacterium) that is transmitted between species (such as Rabies and Foot and Mouth Virus) is known as Zoonosis.
Since Covid 19 is a 96% match with the virus genome found in bats, it was suspected that the present pandemic originated from them, inter alia since bats are fertile ground for the development of zoonotic viruses due to their open control immune systems.
Similarly to other corona viruses such as SARS and MRS, which originate in bats, and in light of the assumption that in order to create zoonoses transmitted from one animal to another as well as to humans, an agent is required.
The most probable assumption is that Covid-19 originated through an agent such as rats, snakes and other “dishes” as a result of poor storage facilities of food products or insufficient cooking – a characteristic trait of Far East markets.
In terms of architecture, there are now three main issues under discussion: creating proper conditions for confronting the pandemic, maintaining proper hygiene conditions for treatment, and providing spatial conditions for the isolation required to prevent infection.
One of the most meaningful turning points in hospital planning took place during the 40's when research provided at the conclusion that germs are not transmitted by air, but rather by humid agents - drops of saliva or phlegm emitted into the air. A 1934 study on the subject of aerial contagion indicated a direct correlation between the size of the drops, their evaporation and their dropping speed to earth, coming to the conclusion that the smaller the drops the longer they remain in the air, thus eliminating risk of aerial contagion from a distance higher than two meters.
Today, thanks to digital technology, these conclusions have changed dramatically and the assumption is that the drops in the air survive for a longer period, and may hover for a distance of at least six meters.
At any rate, this distinction led to a significant change in hospital planning, which until then was based on several separate wings (such as the Tel Hashomer military hospital), and from then on allowing the building of multi-storey hospitals such as Beilinson, Hadassah, Shaare Zedek, and many others around the world.
Another “superstition”, which by the way, has not yet been negated, was that germs are sensitive to light and therefore reproduce dramatically in dark spaces – which seemed to explain the spread of epidemics in poor, dark and crowded neighborhoods.
For safety’s sake, hospitals all over the world were built with large windows, believing that if they don't help, they don't do any harm. Nowadays we know that light may also contribute to improving patients’ moods, something many studies have shown to be an important condition for improving the immune system.
One way or another, the key question on the subject of contagion is still whether germs in general and viruses in particular are aerially transmitted.
Since the main symptom of the corona virus is pneumonia, the prevailing medical opinion is that the source of infection lies in respiratory drops emitted to the air by sneezing, coughing or even speaking (aloud). As mentioned, these drops sooner or later land on a surface after remaining in the air for anything between several seconds to several minutes, according to their size. The larger the drop, the quicker it falls, so that the splash of a sneeze spreads through the air and moves in the wind for larger distances. Therefore one must distinguish between the structure of its physical content and the air surrounding it.
In this respect, while surfaces can be cleaned and disinfected, the mediating air between human beings – between them and their environment, cannot be disinfected without causing more damage than the virus itself.
The correlation between field conditions and the risk of infection constitutes a central issue when planning hospitals, where the issue of separating patients from each other, from staff, and the medical equipment requires deep planning consideration. This refers to every architectural facet in contact with people, from walls and floors, to furniture and air conditioners. This problem actually prevails in all institutions, partially in the closed ones - prisons, synagogues, homes for the elderly, hotels, and culture and sports facilities.
In order to understand the correlation between quality of air, humidity and temperature, it is necessary to clarify the distinction between two basic concepts: absolute humidity (AH), and relative humidity (RH). Both of them refer to a water mass in a certain quantity of air. However, while relative humidity is temperature dependent, absolute humidity is not. This is due to the fact that water molecules’ bearing capacity increases according to the temperature, and any attempt to add water to saturated air will increase evaporation.
Various studies have found a direct correlation between cold weather and the spreading rate of viruses related to respiratory infections. Thus, for instance, the recent outbreak of corona in the northern cities of China, Iran, Italy and the United States occurred at the same time along the same latitude.
A study carried out in Finland found that the prevalence of respiratory infections rises when the temperature drops and humidity rises. In contrast, studies dealing with the impact of humidity conditions on increasing influenza in the United States indicates the absence of a clear correlation between low or high absolute humidity. However, the appearance of the virus in winter increases the survival ability of the virus in the weeks prior to the appearance of influenza. Hence, it was suggested that in order to prevent the virus from spreading one must pay attention to the weather conditions in the weeks prior to its appearance, and not necessarily to the time of occurrence.
In any case, these conditions are typical of transition periods when air conditioners are used less (both for cooling or for heating) - a sign that the key lies in the difference between natural and conditioned air.
An air-conditioned room is indicative of an environment characterized by a low temperature and relatively low humidity (whether hot or cold), while natural air may contain high or low absolute humidity irrespective of the temperature.
Since cold air constitutes a higher potential for surviving the virus, while a high temperature diminishes survival; and since high humidity encourages infection while low humidity diminishes it, the optimal solution seems to lie in controlling the quality of air.
In this respect, it is worth paying attention to three conflicts: the first is that conditioned air is colder and as such could increase virus survival. However it is less humid and therefore likely to diminish infection. The second conflict is that air-conditioning is captured in a closed circuit, which might encourage infection factors, mainly in closed rooms. Hence, one of the key problems in hospital planning is neutralizing the air of infection agents. And this brings us to the third conflict. The solution adopted in public buildings, and especially in hospitals, is based on controlled air changing through negative pressure; a method that actually negates the conventional principle of air-conditioning whereby re-cycling the air constitutes energy saving.
However, in light of the fact that hospitals are the most intense arenas for interaction, they may shed light on the architectural inability to provide proper conditions for managing the battle against a viral pandemic, where the crucial principle is isolation, contrary to its embedded traditional principle of encouraging social interaction.
It is worth noting that what saved the situation was the great progress made in developing electronic sensors and monitoring devices that enable virtual interaction through cameras and imaging devices, facilitating remote monitoring and treatment, as well as successful, complex surgery.
Since critical situations like the Corona pandemic concerns an invisible adversary, the struggle is mainly against its symptoms. In such cases, virtual interaction should be taken into consideration as a built-in alternative in every plan from now on. Thus, when necessary, social interaction innate to architecture in conventional situations, may enable proper isolation without neutralizing billions, as Covid-19 has done without any effort at all.
However, as in many other cases, until the coming of the Messiah, salvation might come from the lowest-tech aspect of architecture – that of the sewer system. Based on a hierarchical structure, it allows for a relatively simple detection of the virus spread at the level of the building, neighborhood, city, and state.
This is not a new method, and as known, it has been in use in various ways for centuries, such as for detecting Bilharzia and Cholera in South Africa, Egypt, Italy (Venice) India or even Holland, where sewage and drainage systems frequently intersect, constituting a risk of spreading disease through bathing or drinking water.
And a word in conclusion: The complacency of the architectural milieu, its recent failure exposed in the total paralysis of the health system, long documented in the Ministry of Health’s Guidelines for hospital planning. There, clearly written, is a directive to provide one isolation room (with the possibility of an extra bed…) in each emergency ward based on 50 beds. Since the emergency rooms in Israel included about 700 beds at the outbreak of Corona, the number of isolation rooms were nil, and the most progressive hospitals proven to be worthless in the face of the need to isolate hundreds or thousands of people. Instead, it was necessary to erect field isolation tents, or temporarily occupy existing buildings not intended for this.
In this light, the flagship of architecture in terms of spatial relations must shift from “social interaction” to isolation provision when necessary.
