On Distance Respiratory Virus Transmission : Sate of Evidence

Aim of this work is to verify hypothesis of air-borne transmission on distance related some respiratory and other virus and to compare with actual covid-19 pandemic diffusion. After an analysis of relevant literature involved and submitting an experimental hypothesis a global conclusion is submitted for further research activity. Some peculiarity in Covid-19 diffusion velocity and mortality rate in some high polluted world region Contribute to increase the interest in this topics. We based research - study examines by Research states that and are examined. the population is included as an effective- parameter for evaluation. The analyses are conducted based on Spearman's correlation- coefficients. The results showed that the highest- correlations were observed for wind- speed 14 days ago, and temperature on the day, respectively. The study results may guide decision-makers on taking specific- cities. meteorological- the average wind- speed in 14 days the of cases. The The also


INTRODUCTION
Respiratory virus diffusion and spread are a real interesting phenomena and a deep knowledge in this Field make possible to better acts towards also some relevant infectious disease like covid-19 pandemic. It is so very interesting to observe behavior of other virus like avian influenza, H5 N1, SARS, MERS and other like small-pox. What is interesting is the various evidence of on distance transmission reported on scientific literature In human field but also in veterinary settings. Before to start this work it is really interesting to observe .
"Aerosol--particles in the atmosphere have recently been found to contain a large number of chemical-elements and a high -content of organic -material. The latter property is explicable by an inverted micelle model. The aerosol-sizes with significant atmospheric life-times are the same as those of single-celled organisms, and they are predicted by the inter-play of aero-dynamic drag, surfacetension, and gravity. We propose that large-populations of such aerosols could have afforded an environment, by means of their ability to concentrate molecules in a wide -variety of physical-conditions, for key chemical trans-formations in the prebiotic-world. We also suggest that aerosols could have been precursors to life, since it is generally agreed that the common ancestor of terrestrial-life was a single-celled organism. The early -steps in some of these initial trans-formations should be accessible to experimental work of investigation." Atmosphere can be considered a real complex-environment and since origin of life and in the following evolution pattern. A mixture of different gases, aerosol's , steam and particulate matter, dust in a continuous movement

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Current -theories of influenza viral-epidemiology have not good explained the persistence, seasonality, and explosive-outbreaks of the virus over large geographic-areas. It is postulated in this scientific work paper that atmospheric -dispersion and inter-continental scale transport of air-borne-aerosolized influenza -virus may contribute to the spread,-persistence, and ubiquity of the disease, the explosiveness of epidemics, and the prompt region-wide occurrence of out-breaks and that seasonal-changes in circulation-patterns and the dispersive character of the atmosphere may help to explain the regular annual -cycle of influenza -activity". In article Aerobiology and Its Role in the Transmission of Infectious Diseases 2013. "Aero-biology is the study of the processes involved in the movement of micro-organisms in the atmosphere -environment from one geo-graphical location to another location , including the aerosolized-transmission of the disease. The aerosolized -transmission of disease occurs through both: "droplet" and by "air-borne" means. Droplet-transmission is defined as transmission of diseases by expelled -particles that are likely to settle to a surface quickly, typically within three -feet of the source . In order for an infection to be caused by droplet-transmission, a susceptible -individual must be close enough to the source of the infection ( an infected-individual) in order for the droplet ( that contain the infectious-micro-organism) to make contact with the susceptible-individual's respiratory -tract, eyes, mouth, nasal passages, and so forth . Air-borne-transmission is defined as the transmission of infection by expelled-particles that are comparatively smaller -size and thus can remain suspended in air for long -periods of time.
Air-borne -particles are particularly worrisome simply because they can remain suspended in the air for extended -periods of time.
Seminal studies in 1930s -1940s demonstrated that air-borne -particles can remain air-borne for as long as 1 week after initial aerosolization, and suggested further that these particles likely remained air-borne for much longer-time. They thus potentially expose a much higher number of susceptible individuals at a much greater distance from the source of infection. Depending on the environmental -factors ( meteorological -conditions outdoors and fluid-dynamic effects and pressure differentials -indoors), airborne -particles are easily measured 20 m from their source . These factors would be of no concern but for the fact that air-borne-bacterial, viral, and fungal particles are often -infectious.

Environmental Considerations:
While the air-borne-transmission of disease depends on several physical-variables endemic to the infectious particle, the environmental-factors substantially influence the efficacy of air-bornedisease transmission. The environmental -factors most often cited as modifying the air-borne-transmission of disease are temperature and relative-humidity . They help determine whether or not an air-borne -particle can remain infectious. The size of infectious-particles can change depending on relative humidity and temperature ( that influence desiccation / hygroscopicity). An added complication is the fact that temperature /humidity influence viral-bacterial, and the fungal particles differently .
Temperature is an important factor affecting virus-survival . as temperature rises, virus -survival decreases . low -temperatures ( 44.6°F-46.4°F) have been suggested to be ideal for air-borne-influenza survival, with survival decreasing progressively at moderate ( 68.9°F-75.2°F) and high-temperatures ( >86°F). This relationship holds across a range of relative-humidities ( 23%-81%) . Influenza has also been shown to be transmissible via air-borne -vector under cold, dry -conditions . While relative humidity is recognized to be a factor in the viability of air-borne and droplet viraltransmissions. the report of Arundel et al. showed that minimalsurvival for both lipid-enveloped and non-lipid-enveloped viruses occurs at relative humidities ( between 40% and 70% )contrasts with that for influenza noted above." "Definitions :Strictly speaking, 'aerosols' refer to particles in suspension in a gas, such as small -droplets in air it is usually accepted that: a) small -particles of < 5-10 μm aero-dynamic diameter that follow airflow stream-lines are potentially capable of short and long-range transmission; particles of < 5 μm readily penetrates the airways all the way down to the alveolar-space, and particles of < 10 μm readily penetrates below the glottis b) large-droplets of diameters > 20 μm refer to those that follow a more ballistictrajectory ( falling mostly under influence of gravity), where the droplets are too large to follow inhalation airflow-stream-lines. c) 'intermediate-particles' of diameters 10-20 μm, will share some properties of both small and large droplets, to some extent, but settle more-quickly than particles < 10 μm and potentially carry a smaller infectious-dose than large (> 20 μm) droplets. 'Aerosols' would also include 'droplet-nuclei' which are small particles with an aero-dynamic diameter of 10 μm or less, typically produced through the process of rapid-desiccation of exhaled respiratory -droplets . in some conditions , like in strong ambient air crossflows, larger-droplets can behave like aerosols with the potential to transmit infection via this route .
Many different kind of properties can be inferred from this, the penetration of the lower-respiratory tract (LRT), as at greater than 10 μm diameter, penetration below the glottis rapidly diminishes, as does any potential for initiating an infection at that site. any such potential for depositing and initiating an LRT infection is less likely above a droplet-diameter of 20 μm, as such large-particles will probably impact onto respiratory epithelial-mucosal surfaces or be trapped by the cilia before reaching the LRT ". According E Domingo :"Viruses are parasites of cells and abundant. They might have arisen during an early-phase of the evolution of life on Earth dominated by ribonucleic-acid , or when a cellular world was already well established. The theories of the origin of life on-Earth shed light on the possible origin of primitive-viruses or virus-like genetic elements in our biosphere.

Related Origin of life :
A crucial experiment showed that components of biological-molecules could be obtained from inorganic-precursors. He mimicked the conditions thought to be prevalent in the primitive-Earth, and mixed H2, NH3, and CH4 in a sealed reactor with an influx of water-vapor. Synthesis of a number of organic -compounds occurred under the influence of electrical-discharges. The de-novo synthesized-chemicals included amino -acids . Other researchers and scientist followed the Miller's experiment using other starting chemical-mixes and confirmed that key-components of the macro-molecules that are associated with living-materials ( purines, pyrimidines, amino acids) could be made from precursors, which were abundant in the primitive-Earth environment or its atmosphere. Intense UV ultraviolet -irradiation may have contributed to the synthesis of compounds relevant to life: ammonia, methane, ethane, carbon monoxide, formaldehyde, sugars, nitric acid, and cyanide. Complex organic compounds ( aromatic hydrocarbons , alcohols) are found in inter-planetary dust, and meteorites, and they can be generated under the effect of the cosmic-stellar radiation. Many organic-compounds could have Luisetto M, et al.

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been produced within the Earth atmosphere or away from it, and be transported to the Earth surface by meteorites from comets, or rain, to become the building-blocks for additional life-prone organic molecules. Places at which peptide bond formation and prebiotic-evolution could have been favored are hydro-thermal systems and the interface between ocean and atmosphere.
The prebiotic -synthesis of potential building blocks-which might have been initiated earlier than about 5000 million years agorenders plausible the existence of a pre-RNA era that was then replaced by an RNA world in the late Hadean early Archean-periods on the Earth. This stage should have been followed by one in which RNA-was complemented by DNA as a repository of genetic-information"

MATERIALS AND METHODS
With an observational approach some relevant literature is analyzed and an practical experience hypotesis Is submitted to the researcher to produce a global conclusion related the topics of this work. All literature come from biomedical datatbase ( PUB MED) .

RESULTS
This research-paper employs computational multi-phase fluiddynamics and heat transfer to investigate transport, dispersion, and evaporation of saliva particles arising from a human cough. An ejection process of saliva-droplets in air was applied to mimic the real event of a human cough. We employ an advanced threedimensional model based on fully-coupled Eulerian-Lagrangian techniques that take into account the relative-humidity, turbulent-dispersion forces, droplet phase-change, evaporation, and breakup in addition to the droplet-droplet and droplet-air interactions. We computationally-investigate the effect of wind-speed on social-distancing. For a mild human -cough in air at 20 °C and 50% relative humidity, we found that human saliva-disease-carrier droplets may travel up to un-expected considerable-distances depending on the wind-speed. When the wind speed was about approximately zero, the saliva -droplets did not travel 2 m, which is within the social -distancing recommendations. at wind -speeds varying from 4 km/h to 15 km/h, we found that the saliva droplets can travel up to 6 m with a decrease in the concentration and liquid droplet -size in the wind-direction. Our findings imply that considering the environmental -conditions, the 2 m social distance may not be sufficient. Further next research is required to quantify the influence of parameters such as the environment's relative -humidity -temperature among others". (1) Yang Zhao et al : "The 2015 outbreaks of highly pathogenic avian -influenza (HPAI) H5N2 in the U.S. devastated its poultry-industry and resulted in over $3 billion economic-impacts. Today HPAI continues eroding poultry operations and disrupting animal -protein supply chains around the world. Some Anecdotalevidence in 2015 suggested that in some cases the AI -virus was aerially -introduced into poultry houses, as abnormal bird -mortality started near air inlets of the infected-houses. This work -study modeled air movement trajectories and virus-concentrations that were used to assess the probability or risk of air-borne-transmission for the 77 HPAI cases in Iowa. The results show that majority of the positive cases in Iowa might have received air-borne -virus, carried by fine particulate -matter, from infected farms within the state ( intrastate) and infected -farms from the neighboring states ( interstate). The modeled air-borne-virus concentrations at the Iowa recipient sites never exceeded the minimal infective-doses for poultry. The continuous -exposure might have increased airborne -infection risks. In one worst-case scenario ( maximum virus shedding rate, highest emission-rate, and longest half-life), 33 Iowa cases had > 10% (three cases > 50%) infection-probability, indicating a medium to high-risk of air-borne -transmission for these cases. Probability of air-borne HPAI infection could be affected by farm type, flock-size, and distance to previously infectedfarms; it can be markedly reduced by swift depopulation and inlet air filtration. The research results provide insights into the risk of air-borne-transmission of HPAI virus via fine dust-particles and the importance of preventative and containment strategies such as air -filtration and quick de-population of infected flocks." (2) A Ssematimba et al written : " Fever Virus (CSFV), and Foot-and-Mouth Disease Virus are highly contagious-viruses affecting livestock and are among the World Organisation for Animal Health listed diseases. The consequences of their recent-epidemics in the Netherlands have been enormous and include high mortality -rates, economic losses incurred in implementing control strategies and reduced exports, for HPAI, a risk of spread to humans . During 2003 HPAI-epidemic in Netherlands, following detection of the first out-breaks in late February, movement bans were implemented followed by other control-measures. more farms became infected and therefore in the second-week of March the measure of preventively culling contiguous-flocks was adopted. In the end, 255 flocks were affected over the course of the epidemic and close to about 30 million-birds were culled; the virus was transmitted to 89 people causing one fatality . Between 80% -90% of the outbreaks occurred through un-traced routes, with Luisetto M, et al.

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the farm infection-hazard increasing in the vicinity of earlier-infected (but as yet undetected) -farms . The sustained between-farm transmission despite extensive control-measures demonstrated the difficulty of controlling HPAI spread in poultry-dense areas.
The mechanisms underlying the between-farm spread of HPAI are not clearly understood, especially those of indirect -transmission (involving vectors or fomites and possibly wind-borne transfer), as opposed to direct transmission (transportation of live animals between farms) . Indirect-transmission has played a major-role in large epidemics involving viruses such as CSFV and FMDV .
In the analysis of the Dutch 2003 HPAI epidemic data, Boender et al. used statistical spatial-temporal modeling-techniques and identified high-risk areas for epidemic spread. The same technique of using a spatial-transmission -kernel was used by in studies on the between-farm spread of FMDV in Great Britain helpful for the development of control-strategies laid out in contingency plans, were gained from these analyses, a lack of mechanistic ( opposed to the statistical methods ) understanding of the betweenfarm spread currently -impedes the further improvement of these strategies. The extent to which biosecurity-measures on farms contribute to limiting indirect-transmission is unclear, as is how these measures can be improved. With stringent control measures put in place during epidemics including bans on the movement of animals, the direct-spread of the virus is reduced. Indirect-routes such as contamination of personnel and fomites do become the only pathway of virus spread. Indirect-transmission could arise from human-vectors transferring infective excreta such as manure from infected to recipient-animals, mechanical-transfer of excreta or a possible combination of these mechanisms. The need to determine whether wind-borne transportation of the virus is one of the untraced -routes of HPAI spread between-farms is apparent. The simplest way possible is that where the virus is transported by wind from an infected farm directly to an uninfected farm as has been considered in plume models for FMDV spread. the dispersal may be through a multi-stage process. In this a process, the virus may be transported from infected-animals to recipient animals by wind during certain parts of the route and by other means (humans , vehicles) on other parts. Both this scenarios require quantitative-insight into the deposition-pattern of (contaminated) farm -dust. Davis et al. Conducted a study on the spread of Equine Influenza in Australia in 2007. They concluded that virus was spread over 1-2 km via wind-borne aerosols. A quantitative-understanding of the spread of contaminated-farm dust between locations is a prerequisite for obtaining much-needed insight into one of the possible mechanisms of disease spread between farms. we develop a model to calculate the quantity of contaminated farm-dust particles deposited at various locations down-wind of a source farm and apply the model to assess the possible contribution of the wind-borne route to the transmission of Highly--Pathogenic Avian Influenza virus (HPAI) during the 2003 epidemic in the Netherlands. The model is obtained from a Gaussian Plume Model by incorporating the dust deposition-process, pathogen decay, and a model for the infection process on exposed farms. Using poultry-and avian influenza-specific parameter values we calculate the distance-dependent probability of between-farm transmission by this route. A comparison between the transmission risk pattern predicted by the model and the pattern observed during the 2003 epidemic reveals that the wind-borne route alone is insufficient to explain the observations although it could contribute substantially to the spread over short-distance ranges, explaining 24% of the transmission over distances up to 25 km. (3)".
The results of a detailed-assessment study of the atmospheric -conditions when foot-and-mouth disease (FMD) virus was released from Burnside-Farm, Heddon-on-the-Wall, Northumberland at the start of the 2001-epidemic in the UK united kingdom are consistent with the hypothesis that the disease was spread to seven of the 12 -farms in the immediate-vicinity of the source by air-borne-virus, and air-borne-infection could not be ruled out for three other premises; the remaining 2 premises were unlikely to have been infected by air-borne -virus. The distances involved ranged from less than 1 km up to 9 km. One of the farms which was most probably infected by air-borne-virus from Burnside -Farm was Prestwick-Hall-Farm, which is believed to have been key to the rapid-spread of the disease throughout the country. the results of detailed atmospheric-modelling, based on a combination of clinical -evidence from the field and laboratory-experiments have shown that by assuming a relationship between the 24-hour average virus -concentrations and subsequent infection, threshold infection -levels were seldom reached at the farms close to Burnside-Farm. significant short-term fluctuations in the concentration of virus can occur, and short-lived high concentrations may have -increased the probability of infection and explain this discrepancy." (4) An incursion of equine influenza (EI) occurred in Australia. Accurate maps of property boundaries were used to examine pattern and mechanism of local-spread of EI. This study focussed on a cluster of infected -premises (IPs) at Park -Ridge, a peri-urban suburb 26-km south of Brisbane, in the Queensland. The cluster recorded 437 IPs and 81% of these were not contiguous to a previously IP. The mean-distance from each new IP to the closest previous IP was 0.85 ± 1.50 km with a range of 0.01-12.94 km. 82 % of new IPs were within 1 km of a previous IP. The spatial mean for each week's new IPs showed a consistent -trend of movement from east to west throughout the epi-zootic consistent with the predominant wind patterns. The findings were consistent with the conclusion that : EI will routinely spread over 1-2 km via wind-borne aerosol. The availability of highly -accurate maps of property boundaries during the 2007 incursion in eastern Australia provided an opportunity to examine pattern and mechanism of spread of EI in fine -scale. 81% of new IPs in the Park -Ridge cluster were not contiguous to existing IPs and therefore spread of EI to these new IPs could not involve direct horse-to-horse contact or droplet spread (if there was total compliance with movement -controls) because these 2 mechanisms are limited to spread over very short distances ≤1 m . There was no -infection reported in the Park -Ridge area until 13 September; 2 weeks after introduction of the standstill for all horses, therefore, the spread of EI could not be explained by direct-contact arising out of horsemovement. The case for aerosol-spread is supported by the observed wind-patterns. Throughout the period of the epizootic, the winds were predominantly from the east and this was consistent with the observed spread of the epizootic from east to west acrossthe cluster .

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Over 75% of the observed instances of local spread of EI in the Park-Ridge cluster were to properties within 800 m of a known existing IP."(5) The ability of porcine-reproductive and respiratory syndrome-virus (PRRSV) and Mycoplasma-hyopneumoniae to be transported over long-distances via the air-borne -route was evaluated. A source population of 300 grow-finish pigs was inoculated with PRRSV MN-184 and M. hyopneumoniae 232 and over a 50-day period, air samples were collected at designated distances from the source herd using a liquid cyclonic-collector. This is the first report to provide evidence of long distance airborne -transport of PRRSV and M.-hyopneumoniae. This research study provides swine veterinarians and producers with proof that long distance air-borne -transport of economically significant pathogens of swine is possible and identifies meteorological conditions significantly associated with these events. Whether either agent could have been transported beyond the 4.7 km sampling point can-not be answered at this time; future studies involving longer-sampling distances and extended sampling periods may help to collect a larger number of samples and answer this question, as well as facilitate a more in-depth analysis of associated meteorological-conditions." (6) (Figure 2-3) ( Table  1).

Figure 2:
The distance-dependent probability of infection for the parameter values given in and the transmission kernel (and its 95% confidence bounds.

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ronment " and diffusion of some relevant virus? Pianura-padana is famous for its kind of climate with lots of fog in some season, but also for air-pollution as reported by EPHA and other org." (7) " According GW Hammond : Long-range transport accompanied by atmospheric dispersion would inevitably lead to much lower down-stream concentrations. some relatively undiluted air-parcels might make it across the Pacific-Ocean, and the virulence of aerosolized influenza-virus at low concentrations might still be sufficient to cause infections. Influenza-studies in mice have shown a greater infectivity of air-borne versus intranasal-inoculation of virus. Knight demonstrated in volunteers that influenza virus is 5 to 10 times more infectious when introduced by the aerosol -route than by the intranasal-route and that adenovirus type 4 is 70 times more infectious by the aerosol -route. Aerosolized influenza-A virus produces illness in humans at dosages indistinguishable from one infecting particle. Measurements of aerosol concentrations and size distributions made in a pristine area of Alaska indicate that, on average, winter -air masses with trajectories off the Pacific -Ocean have 100 accumulation-modesized particles per cubic centimeter. Some of the aerosols entering North America may contain viable influenza virus. Long-term survival of aerosolized influenza-virus. " (8) In Preprint "Analisys of some worsening factor involved whit covid-19 and other respiratory virus diffusion " 2020 was reported :"Observing the different velocity-rate of diffusion of covid-19 disease and other relevant respiratory -virus is possible to verify a relationship with air -pollution in some world-regions characterized by great industrial-activity and determinate climate-condition. The air pollutant whit various mechanism produce in respiratory-tract an environment able to favour Also respiratory-virus attack. This especially in some kind of patient like elderly and with polipathology. It is related whit level of some air pollutant but also to the global time of exposition ( in example during 3-5 years)."(9) According Guangbo Qu et al : " Transmission via the inhalation of small, exhaled respiratory -droplets may occur as the aerosol-droplets remain air-borne for prolonged-periods, mediating long-range human-to-human transmission via air-movement. the relative contributions of large respiratory droplets, smaller airborne -aerosol, or direct surface contacts to the transmissibility of COVID-19 still need to be evaluated to enable a fully-effective control of transmission -infection." (10) Chandini Raina Ma-cIntyre et al : " Related small-pox diffusion: "In addition to direct respiratory-transmission from person to person within 1-2 m of spatial separation, a more distant transmission has been described. Whilst it is well-established that air-borne-infection can occur , the spread of small-pox by means of "aerial-convection" is less well-understood. Aerial convection refers to transmission over a substantial distance, (greater than expected during direct person to person respiratory-transmission of 1-2 metres and possibly aided by wind or air currents) a concept accepted by many epidemiologists. the Ministry of Health regulations ( Britain) in the 1940s stipulated that small-pox-hospitals should be "at least a quarter of a mile from another institution or a population of 200, and at least a mile from a population of 600" . (Figure 4-6)A 2 distinct phenomena of air-borne-transmission of variola-virus (small-pox) were described in the pre-eradication era-direct respiratory -transmission, and a unique phenomenon of transmission over greater-distances, referred to as "aerial -convection". We conducted an research-analysis of data obtained from a systematic-review following the PRISMA criteria, on the long-distance transmission of small-pox. Of 8179 studies screened, 22 studies of 17 outbreaks were identified-12 had conclusive evidence of aerial-convection and 5 had partially conclusive evidence. Aerial-convection was first documented in 1881 in England, when small-pox incidence had waned substantially following mass-vaccination, making unusual-l transmissions noticeable. National policy at the time stipulated spatial separation of smallpox -hospitals from other buildings/ communities. The evidence supports the transmission of small-pox through aerial-convection at distances ranging from 0.5 to 1 mile, and one instance of 15 km related to bioweapons testing. Other kind of explanations are also possible, such as missed-chains of transmission, fomites or secondary aerosolization from contaminated-material such as bedding. The window of observation of aerial-convection was within the 100 years prior to eradication. Aerial-convection appears unique to the variola -virus and is not considered in current hospital-infection control protocols. Understanding potential aerial-convection of variola should be an important consideration in planning for small-pox treatment facilities and protecting potential contacts and surrounding-communities. the evidence from these outbreaks is supportive of aerial convection of small-pox at distances of more than a mile in some cases and is biologically-plausible due to higher-concentration of virus in the lower-respiratory tract, environmental-factors such as wind, and low infectious -dose. In many of the observed long-range transmissions, there was a temporal association between potential exposure to a known-case and illness. It is possible, that some cases of small-pox were "super-spreaders" with much higher viralshedding than others. This has been seen with other viral respiratory-pathogens such as SARS. super-spreaders could explain long-range transmission. " (12) Chen P-s et al :"The spread of influenza and highly-pathogenic avian-influenza (H5N1) presents a significant threat to the human-health. Avian-influenza outbreaks in downwind areas of Asian dust storms (ADS) suggest that viruses might be transported by dust -storms We developed a technique to measure ambient-influenza and avian influenza-viruses. We then used this technique to measure concentrations of these viruses on ADS days and back-ground days, and to assess the relationships between ambient-influenza and avian influenza-viruses, and airpollutants. A high-volume air-sampler was used in parallel with a filter -cassette to evaluate spiked-samples and un-spiked samples. Then, air-samples were monitored during ADS seasons using a filter-cassette coupled with a real-time quantitative polymerase chain reaction (qPCR) assay. Air-samples were monitored during ADS-season (1 January to 31 May 2006). We successfully quantified ambient influenza-virus using the filtration/real-time qPCRmethod during ADS-days and back-ground days. this is the first report describing the concentration of influenza virus in ambient air. In both the spiked and un-spiked samples, the concentration of influenza virus -sampled using the filter cassette was higher than that using the high-volume sampler. The concentration of ambient influenza-A virus was significantly higher during the ADS-days than during the background-days.Our data imply the possibility of long-range transport of influenza-virus." We analyzed the temporal -spatial distributions of cases in a large community outbreak of SARS in Hong Kong and examined the correlation of these data with the three-dimensional spread of a virus-laden aerosol plume that was modeled using studies of airflow-dynamics. methods We determined the distribution of the initial 187 cases of SARS in the Amoy -Gardens housing complex in 2003 according to the date of onset and location of residence. We then studied the association between the location (building, floor, and direction the apartment-unit faced) and the probability of infection using logistic-regression. The spread of the air-borne, virus-laden aerosols generated by the index patient was modeled with the use of airflow-dynamics studies, including studies performed with the use of computational fluid-dynamics and multizone-modeling. results The curves of the epidemic suggested a common source of the outbreak. All but 5 patients lived in seven buildings (A to G), and the index patient and more than half the other patients with SARS (99 patients) lived in building E. Residents of the floors at the middle and upper levels in building E were at a significantly higher-risk than residents on lower-floors; this finding is consistent with a rising plume of contaminated warm-air in the air shaft generated from a middle-level apartment unit. The risks for the different units matched the virus concentrations predicted with the use of multizone -modeling. The distribution of risk in buildings B, C, and D corresponded well with the three-dimensional spread of virus-laden aerosols predicted with the use of computational fluiddynamics modeling. conclusions Air-borne -spread of the virus appears to explain this large community outbreak of SARS, and future efforts at prevention -control must take into consideration the potential for air-borne -spread of this virus." According Coccia M :" The accelerate and vast diffusion of CO-VID-19 in North Italy has a high association with air --pollution. Hinterland -cities have average days of exceeding the limits set for PM-10 (particulate matter 10 micrometers or less in diameter) equal to 80 days, and an average number of infected more than 2,000 individuals as of April 1st, 2020, coastal-cities have days of exceeding the limits set for PM-10 equal to 60 days and have about 700 infected in average. Cities that about average number of 125 days exceeding the limits-set for PM-10, last year, they have an average number of infected-individual higher than 3,200 units, whereas cities having less than 100 days (average number of 48 days) exceeding the limits set for PM10, they have an average number of about 900 infected-individuals. The results reveal that accelerated transmission-dynamics of COVID-19 is due to mainly to mechanisms of air pollution-to-human transmission rather than human-to-human transmission. The finding here suggests that to minimize future epidemic similar to CO-VID-19, the max number of days per year in which cities can exceed the limits set for PM-10 or for ozone, considering their meteorological condition, is less than 50 days. After this critical threshold, the analytical out-put here suggests that environmental inconsistencies because of the combination between air-pollution and meteorological conditions (with high moisture%, low wind speed and fog) trigger a take-off of viral infectivity (accelerated epidemic-diffusion) with damages for health of population, economy and society." "several-studies have established that in-uenza-virus transmission and virulence depend also on meteorological-conditions such as temperature, relative humidity and wind-speed" N. Scafetta : "In January -February, the 2 locations shared strikingly similar weather conditions, but in March Wuhan got warmer fast while the Italian provinces experienced cold weather similar to that of Wuhan in February. These facts could explain why the COVID-19 pandemic-spread equally fast in both regions, but the Italian regions were more-severely affected. in Italy, the cold-weather lasted longer with unusual cold-weeks at the beginning and the end of March, favoring the pandemic -spread. The mean weather-condition of March for each Italian region with their population-densities. The table's rationale is that most people who died were infected in March. The data indicate that the colder northern-regions with temperature roughly ranging between 3-C -14-C and with low-speed winds roughly ranging between 8 km/h and 12 km/h were those most affected by the pandemic. The number of deaths sharply decreases by moving toward the southern -regions that were on average about 2-C warmer. The latter regions also had stronger wind roughly ranging between 12 km/h and 15 km/h. Northern-regions were also slightly dryer (RH = 66%) than the Southern -ones (RH = 73%)""In this research -study, we collected samples of suspended particulate matter, or inhalable dus-t fraction, inside, upwind Luisetto M, et al.

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and at several distances downwind of buildings holding poultry infected with LPAI. The samples were tested for the presence of influenza--virus and for endo-toxins, a marker for microbial exposure of poultry and live-stock, since they have a high presence in commercial farms and can be quantified in the adjacent outdoorair. We demonstrate the wind-mediated spread of influenza viruscontaminated poultry-dust into the environment during influenza-outbreaks in commercial poultry farms based on detection of the air-suspended virus downwind of farms. Influenza-viruses were detected by RT-PCR in filter-rinse fluids collected up to 60 meters down-wind from the barns, but virus isolation did not yield any isolates." "The research -study examines the correlation between weather and corona-virus disease 2019 (COVID-19) by considering nine cities in Turkey. temperature (°C), dew point (°C), humidity (%), and wind speed (mph) are considered as parameters of weather. Research states that the incubation-period of COVID-19 varies from 1 day to 14 days. the effects of each parameter within 1, 3, 7, and 14 days are examined. the population is included as an effective-parameter for evaluation. The analyses are conducted based on Spearman's correlation-coefficients. The results showed that the highest-correlations were observed for population, wind-speed 14 days ago, and temperature on the day, respectively. The study results may guide authorities / decisionmakers on taking specific-measures for the cities. Among the meteorological-parameters, the average wind-speed in 14 days has the highest correlation with the number of cases. The higher the wind-speed is, the more the number of cases is. The results also indicate that the most reasonable timespan is 14 days, meaning that the wind-speed in 14 days of the case should be considered for determining the right-correlation. as expected, the population of a city is highly correlated with the number of cases in the city. and viruses. The strength and duration of UV light exposure can determine the survival of infectious pathogens; In those parts of the country with a higher-average of daily sunshine and those close to the equator, some pathogens lose their infectious ability. If the humidity level are high, then even in the presence of UV-light, the infectious particle can survive for a longer period. It is believed that this is due to the formation of vapor around the aerosolized particles which acts as a barrier to the UV -rays.
Many studies have shown that after tropical-storms, the first quantity of fungal spores is diminished but within a few days, the number of spores will increase exponentially compared to normal environmental-conditions. Socio-economic and living-conditions: Like infectious diseases that are spread via contact, the role of living conditions and socioeconomic factors plays a key role in air-borne-transmission. The spread of disease is much faster in urban-areas compared to rural areas. In urban areas, buildings and other high-rise structures make transmission of bacterial -viral pathogens relatively easy, but in rural areas, air-borne-particles containing fungal -spores are more common. These factors affect the distance of spread, duration, and infectiousness of droplet particles. the influenza virus is relatively easily spread in the northern-hemisphere because of climate-conditions that favor infectiousness of the virus but many bacterial-infections cannot spread outdoors for most of the year, and thus remain in a state of dormancy. The UV -rays of the sun are harmful to bacteria and viruses. The strength and duration of UV-light exposure can determine the survival of infectious-pathogens; In those parts of the country with a higher average of daily -sunshine and those close to the equator, some pathogens lose their infectious-ability. If the levels of humidity are high, then even in the presence of UV-light, the infectious particle can survive for a longer period. It is believed that this is due to the formation of vapor around the aerosolized particles which acts as a barrier to the UV-rays. Many studies have shown that after tropical -storms, the first quantity of fungal spores is diminished but within a few days, the number of spores will increase exponentially compared to normal-environmental conditions. Socio-economic and living conditions: Like infectious-diseases that are spread via contact, the role of living conditions and socioeconomic factors plays a key role in air-borne-transmission. Dwelling and the number of people residing in one area is an important aspect. The spread of disease is much faster in urban areas compared to rural areas. In urban -areas, buildings and other high-rise structures make transmission of bacterial / viral pathogens relatively easy, but in rural-areas, air-borne -particles containing fungal spores are more common. In order to verify HYPOTESIS of relationship between covid-19 spread and its rapid diffusion it is interesting to observe what happened in real air polluted region and related wind activity . This observation must be done in determinate climate condition with geomorphological compartimentation environment (like valley and pianure ) and in region whit charactheristic of wind pattern. ( fast wind or stases condition ). Observing also the presence or not of a VECTOR of diffusion-spread that can not to be easily explained only by direct infection or by droplets or by indoor-air-borne. Every single region-nation can be used as control if there are different involved area , the same observing Behavior of pandemia in mountain region versus non mountain one. All this data must be analized as is done for methanalisis results : for every countries a gradient in diffusion or not ( west -ovest, circle diffusion or other ) providing a fundamental final information: There is or not a vector in virus-diffusion ? All this experimental project can be performed using current epidemiological data of the different countries under verify in period from Genuary-may 2020

DISCUSSION
If observed wht happened in Italy in northern region is possible to verify a rapid outbreak in a wide region And this not explain why in other region this not happened . It was suggested that a PATIENT ZERO was the unique responsible of this rapid evolution, a patient coming from whu -han. But the relevant question is : it is possible thay this traveller from wu-han arrived only in airport of norther Italy big cities and not in south of Italy ?

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Chinese community are currently present in all Italy. So it can be interesting to verify also other hypotesys in diffusion and also related air-borne indoor and outdoor mediated -CARRIED by Particluate matter or by other phenomena ( dust storm for MERS ) . The same the wind speeds (5,19,21)effect in all this condition as well as air pollution. Related this It is Intersteting to observe also that "the Ministry of Health regulations ( Britain) in the 1940s stipulated that small-pox-hospitals should be "at least a quarter of a mile from another institution or a population of 200, and at least a mile from a population of 600" (11) And in Small-pox "in many of the observed long-range transmissions, there was a temporal association between potential exposure to a known case and illness" (12) "Our data imply the possibility of long-range transport of influenza-virus "Observing the diffusion of covid-19 is possible to verify a diffusion from east to ovest then a gradient north south of the world and in some countries like USA a vector diffusion whit more cases in ovest region vs the other . In china the majority of cases was not in the mountain region and in Italy there was a vectors that moved from some Lombardia cities around towards some Emilia Rogmagna ( PC) and towards Piemonte starting from the province near Lombardia first. ( like a vector in a circular diffusion from the centre of the first cluster to periferic ). It is interesting that in Italy there are many relevant great cities not involved with high level of covid-19 disease : it is impossible that some Chinese from whu-han not arrived also in this as in other relevant north italy cities.
Interesting to verify that related COVID-19 in Italy "The number of deaths sharply decreases by moving toward the southern -regions that were on average about 2-C warmer. The latter regions also had stronger wind roughly ranging between 12 km/h and 15 km/h. Northern-regions were also slightly dryer (RH = 66%) than the Southern ones (RH = 73%)" And "among meteorological-parameters, the average wind-speed in 14 days has the highest correlation with the number of cases. The higher the wind-speed is, the more the number of cases is" In this work various evidence related transmission on distance related other virus are reported to testify A common process of some virus.( human and animals )

CONCLUSION
Related the evidence reported in this work, the wide range covered by this ,involving various kind of virus and related humans and animals field, is opinion of the authors that the hypotesys of air-borne outdoor transmission also on distance must be verified to better understand the rapid spread of corona-virus. The presence of vectors in diffusion observed in various countries and continents are condition Of relevant interest and need to be correctly explained .

CLARIFICATIONS
This work is produced with out any diagnostic or therapeutic intent , only to produce hypotesys of work to be submitted to the researcher for further investigations