Table of Contents
- Relation between Flu Epidemics and Warm Weather
- Coronavirus and Early Researches
- Seasonal Behaviour of Coronavirus
- Coronavirus: Impacts of Immune System
- Role of Temperatures on Coronavirus
- Coronavirus and Heat: Animal Experiment
- Corona and Enveloped Viruses
- Coronaviruses on Hard Surfaces at Different Temperatures
- Academic Researches on Temperatures and Coronavirus
- Concluding Thoughts
With the change in season, we see ebb and flow of various transmittable diseases. If we analyze the pattern, we observe flu classically knocks at the door with the arrival of winter. Conversely, we see a rise in diseases like typhoid during hot sunny days. An anomaly happens with the measles as we see their cases dip during summer in the regions with mild temperature, whereas they tend to rise in tropical areas during chilly days.
Perhaps expectedly, people are eagerly waiting to see similar seasonal pattern with covid-19. As we are aware, this coronavirus first came to the fore at the end of the December in china. Since then this virus has spread throughout the world with no leaps and bounds.
Surprisingly, covid-19 disease has erupted largely in those regions where cool weather dominates, which leads us to forecast that this disease may vanish in the thin air as soon as summer arrives. We can see too many theories floating around on this issue. However, most researchers are not that optimistic and warn us not expect big on the virus would fizzle out over hot weather.
And they have every reason to be doubtful. They have no concrete data to rely upon how this virus reacts with the seasons change, as this virus is relatively new to them. The virus that very akin to coronavirus is Sars which first surfaced in 2003. Fortunately, scientist were able to contain this Sars virus at the early stage, hence, no substantial researches were further undertaken as to see how it behaves in different seasons.
Relation between Flu Epidemics and Warm Weather
Warm days are lurking in the horizon. In some areas, as predictions suggest temperature is expected to touch around 30C in coming days. Hopefully, balmy days will allow us to heave a sigh of relief during this lockdown time. However, this respite may put stress on authorities to govern mobs and assemblies.
Nevertheless, researchers also suggest that hot climate can add new dimensions into the virus by presenting whether it responds at the beginning of the warm weather. Usually, flu epidemics have a tendency to fade away as winter finishes. Could warm light of sun, likewise, change the characteristics of the coronavirus and its extent? This burning question is buzzing around epidemiologists and they keep a close eye for that change to happen.
As we are aware, the early studies of former coronaviruses shows that these viruses do change their pattern in different seasons, with a flow happening in winter and waning in summer. Interestingly, these viruses’ peak and flu outbreaks happen together during winter. On the flip side, transmission of coronavirus looks very low during the balmy days.
Here we can recall a research that happened to be conducted some 10 years ago by Kate Templeton who worked at Centre for Infectious Diseases, UK. His study led to discovery of three types of coronaviruses. In this study, all the samples were collected from hospitals from patients with respiratory area contagions. Final result showed that this respiratory infections have a strong correlation with winter seasons. Moreover, the timeframe that was observed for these viruses to trigger infections ranging between late November to mid-April – the same outline was also observed with influenza.
Some symptoms of Covid-19 infer that its nature may change with the seasons. The way this Covid-19 disperse across the globe hints that it may like to dwell on cool environments. Although most of the countries where it spreads consist of different varieties of climates, together with rainy, summer and fall etc.
Recently, the findings of a crucial research on the common coronaviruses was circulated by experts at university college London. They have done a thorough research on samples collected a few years back. After analysis, they came to the conclusion that infections rate of this virus happen to be high in February, whereas during hot and humid days the infections rate falls.
However, the chief researcher of this study, Rob Aldrige, did not show much of enthusiasm while reading the key note.
“We could see continued but lower levels of coronavirus transmission in summer but this may reverse in the winter if there is still a large susceptible population at that point,”
“And given this is a novel virus, we don’t know if a seasonal pattern will hold over the summer given high levels of susceptibility in the population. For this reason, it is crucial that we all act now to follow current health advice.”
Other scientists also put their weight behind this idea. Besides, they sound more pessimistic tone while revealing their findings on seasonal behavior of this virus. They caution that covid-19 virus is a totally different contagious agent. Therefore, building immunity against this virus would be a tall ask for people. Hence, this virus may continue to disperse at existing rate despite imminence of the summer.
“I am sure seasonal variations in the virus’s behavior will play a role in its spread. But compared with the effect we are having with social distancing, it will be a very minor influence. It may produce some marginal effects but these will not be a substitute for self-isolation.”
said virologist Michael Skinner at Imperial College London.
Ben Neuman of Reading University was more categorical.
“This virus started in near-freezing conditions in China, and is rapidly growing both in Iceland and on the equator in Brazil and Ecuador. As winter turned to spring, the virus growth has accelerated worldwide. This is not War of the Worlds, and there is no deus ex machina to reach out of the clouds and put this right. We have to beat the virus ourselves.”
Immunologist Natalie Riddell at Surrey University brings out a new perspective to this issue. He points out as to how our immune system behaves with the seasonal variations. As we have seen arrival of spring induces a very little impact on the behavior of a virus. However, other scientists identify that change in climate can bring change in our immune system.
“Our immune system displays a daily rhythm, but what is less known is how this varies from season to season,” said Riddell.
An analysis, though unpublished, attempts to make a comparison of weather among 450 locations across the globe. This study found some correlation between the dissemination of covid-19 virus and heat & humidity. This experiment also reveal that upper temperature somehow play a role in lower occurrence of Covid-19. In a side note, they didn’t forget to mention that temperature is not the only variable that lead to worldwide discrepancy in incidence.
To add dimensions to that research they forecast that current Covid-19 outbreak is more prevalent in cold weather regions, followed by dry areas. The researchers also articulate that the impact of this virus would be felt less in tropical regions.
The shortcoming of these researches is that analysts depends heavily on computer simulation rather than on real data over a considerable amount of seasons.
It’s a challenging task to draw any conclusive verdict on Covid-19’s seasonality depending on previous coronaviruses. Because, the reasons that scientists use to come to the conclusion that endemic coronavirus are seasonal, those same explanations may not be applicable to Covid-19 pandemic presently.
Besides, as far as seasonal patterns of pandemics are concerned, they don’t follow normal flu chain. As an instance, we can say Spanish flu, which reached pinnacle during the balmy days. On the contrary, we observe widespread of maximum flu during the chilly days.
“Eventually we would expect to see Covid-19 becoming endemic, and it would be really surprising if it didn’t show seasonality then. The big question is whether the sensitivity of this virus to [the seasons] will influence its capacity to spread in a pandemic situation. We don’t know for sure, but it should be in the back of our heads that it is possible.”
Articulates Jan Albert, a professor of infectious disease control who specialises in viruses at the Karolinska Institute in Stockholm.
A group of researchers in France conducted animal experiments to see whether heat can neutralize coronavirus. In this study, their subject was an African green monkey. Deliberately they infected the monkey’s kidney cells with the coronavirus. Later, they put the disease-ridden cells in a 135 degree Fahrenheit chamber. Unfortunately, that 135 degree heat failed to eliminate that virus as the virus lived on in that cell. Scientists eventually managed to burn down the virus exposing it to 196 degree temperature for fifteen minutes, as per the report.
The experiment was conducted in a measured laboratory setting. Besides, the object was an animal cell rather than human ones. Therefore, a big question mark is hanging over the findings of this study. And scientists are doubtful to apply this to real life. Moreover, summer heat will never reach that high in the normal world. However, the best part of the experiment is that the researchers noticed that people infected with Covid-19 got a lesser viral load than that of monkey cells. (Viral load is basically the total volume of virus a host can contain. The lesser a host’s viral load, the fewer contagious they are.) Hence, this little piece of finding gives us hope that probably inferior temperature might help neutralize SAS coV-2 in the setting of human cells.
Corona and Enveloped Viruses
Let’s dig deep as to know why other associated coronaviruses are seasonal. And how it can bring hope to battle this covid-19.
Coronaviruses are belong to the “enveloped viruses” league. The reason for that is they form an oily layer, recognized as lipid bilayer. Besides, this oily coat scattered with proteins which look like points of a crown. In Latin, corona stands for the meaning of crown.
Study conducted on other enveloped viruses finds that presence of heat makes the viruses vulnerable especially those have oily layer. In cold environments, this oily layer get toughen and forms rubber-like state. Here, we can draw the analogy of fat from cooked meat. This fat gets harder as the meat cools off. This hard rubber like oily coat helps live the virus for longer when it survives on outer surface of our body. This phenomenon helps the researchers to draw the conclusion that maximum enveloped viruses have a solid seasonality link.
Another research done on firm surfaces as to see how Sars coronavirus can last on them at different temperature. The findings revealed that sars virus can survive on plastic and stainless steel for around 70 hours. The researchers set the temperatures between 20-24C and humidity at 35-40%. It is still unknown as to how Covid-19 virus would react at different temperatures and moisture. However, study on previous coronaviruses indicates that they can stay alive up to 30 days at 4C.
A research conducted in University of Maryland has found that the typical temperatures in most of the regions that infected by this virus remain below 4-10C along with low humidity. However, tropical areas are not an exception. We have seen significant amount of cases in this regions also.
Another study led by a group of researchers from Harvard Medical School in an attempt to find as to how this virus spread in Asia. The finding of the study doesn’t provide us with much of hope. As the result recommends that there is a loose link between this pandemic and sensitivity of weather.
In their findings they analyse the speedy progress of cases in cold provinces of china. Along with the degree of spread in tropical regions like Singapore. They draw the conclusion that rise in temperature in summer may not help decrease in cases. However, they put emphasis on far-reaching community health involvement in order to curve the pandemic.
Recent coronavirus which causes COVID-19 is a new phenomenon. Scientists have yet come up with such data that can establish that warm weather can create an impact on COVID-19 receding. However, numerous studies are going across the globe on this topic. And some of the early research shows positive findings on this issue. Though early experiments on previous coronaviruses found that they show sign of seasonality in cold climates. Besides, cases of coronavirus are found lower in relatively warmer countries then those in cold regions. Moreover, experiments done on animal cells with heat show positive results. All being well, balmy days will bring a new hope for us and will make this world coronavirus free.
The information provided in this article is accurate as of current time. There is possibility that some information may change with the evolution of COVID-19. Please keep an eye on The WHO, and your local public health department for most recent data and recommendations.