A health expert surmised that the SARS-Cov2 virus might not spread in Nigeria due to hot temperature.
Warmer air holds more moisture; thus preventing airborne viruses from travelling as far as they would in dry air. Still, the jury’s out on whether or not SARS-Cov2 will be resistant or vulnerable to hot temperature.
One of the Nigerian dailies on the 3rd of March 2020 published a story on how coronavirus may not spread in Nigeria due to hot temperatures.
According to the expert quoted in the publication, “hot tropical climate as obtainable in Nigeria could help suppress the spread of coronavirus COVID-19”.
The consultant Dr Adeola Fowotade who made this statement said “some experts think that the covid-19 may behave like the influenza virus which is a seasonal disease common in a colder climate. And since Nigeria has a hotter climate, it will be impossible for and too hot for coronavirus to spread.”
Furthermore, she asserts that the covid-19 outbreak might not go on for too long in Nigeria; possibly receding due to the tropical climate. She added that the droplets generated by the virus could not travel far as this is an envelope virus which cannot survive very long in a hot climate.
The Novel Coronavirus- SARS-Cov2
The emergence of Covid-19 or coronavirus has become a global health concern within a space of three months; it has reportedly spread to over 80 countries so far with about 107,000 confirmed cases and more than 3500 deaths.
Bringing it home, Premium Times on March 9 reported the second case of coronavirus in Nigeria per the Ministry of Health. Importantly, this report came less than a month after the first confirmed case on February 27. All this buttresses the significance of claims regarding this virus and the African context- climate.
Meanwhile, it is important to note that while Covid-19 is closely related to sister viruses SARS and MERS, it is entirely distinct. The acronyms mentioned earlier stand for Middle East Respiratory Syndrome (MERS-CoV) and the Severe Acute Respiratory Syndrome (SARS-CoV), both belonging to the family of coronaviruses.
The relevance of the climate in the discussion
For disease or virus to spread, there are three components responsible for that:
- An agent or pathogens
- A Host or vector
- Environment for transmission
Pathogens (the disease-causing organism, Covid-19 in this case) are carried by vectors (a host) to complete their life cycle. And for their survival, reproduction, distribution and transmission and suitable environmental conditions are imperative.
Therefore, changes in climate and weather conditions may impact infectious diseases through affecting the pathogens, vectors, hosts and their living environment. That is to say that climate conditions can indeed constrain the distributions of contagious diseases; weather can affect the timing and intensity of disease outbreaks.
Can Covid-19 Survive in a Tropical Climate?
Foremost, pathogens need a particular temperature to survive and develop ex vivo (outside a host). And while excessive heat can kill some pathogens, is covid-19 part of this class of organisms? And at what temperature or better still environmental conditions is this possible?
Covid-19 is an emerging disease and the virus itself a new type of coronavirus infection in humans. Consequently, there are still studies ongoing with further information surfacing every day about its pattern of infection in humans. But, SARS-Cov2 belongs to a family of coronaviruses, so what lessons or similarities exist?
Lessons from sister-viruses
One study revealed that coronaviruses could persist on inanimate surfaces like metal, glass or plastic for up to 9 days. It also surmised surface disinfection could efficiently inactivate said infection. This disinfection, however, had to meet specific criteria not limited to the efficacy of removal and least exposure time. The research also considered other factors such as the PH (acidic or alkaline) environment and how it affected the viruses. Additionally, the researchers examined the environmental effects, if any, from embedding the viruses in organic particles.
Another study established that SARS-CoV survived on surfaces such as steel, aluminium, plastic, and silicon rubber for over five days; this was at temperatures between 22-25% and relative humidity of 40-50%. Furthermore, the researchers noted how higher temperatures and relative humidity (RH) reduced the survival rate of the virus. The study noted similar conditions for the HCoV (human coronavirus) at increasing temperature and RH.
While similarities may exist, we still don’t know
Going by the behaviour of sister viruses in different environmental factors, we can surmise that Covid-19 may be influenced by similar conditions. However, we are not suggesting tropical regions would see a halt in the spread of Covid-19. Reports indicate the contrary with the third and fourth instances in Senegal serving as a cautionary tale.
Instead, we should consider factors such as population density and individual hygiene, rather than just the climate. So, while this idea appears perceptible, it is reckless.