Will monsoon impact coronavirus spread?
#GS3 #Health #Environment
Some months ago, when the novel coronavirus epidemic was still emerging in India, it was hoped that rising temperature in the summer months would weaken the potency of the virus and slow down its spread. That did not happen. Now that the monsoon season is here, the likely impact of rain on the virus, and its transmission, is the subject of discussion.
Since it is a new virus, scientists are not yet sure how the rain might affect its behaviour. So the effort is to look for clues in the way other similar viruses behave during the rainy season.
Much still unknown
- Rain brings with it several vector borne diseases like malaria, dengue and chikungunya. In the case of dengue, some studies have shown that excessive rains could disrupt the mosquito’s reproductive cycle and flush out its breeding sites.
- But the comparison that is being made is that with influenza, which, like Covid-19, is a respiratory disease, though there are important differences in the way the two viruses replicate and affect human beings.
- There is no single factor like temperature or rainfall, or staying indoors that can be said to have decisive impact. Many other factors like sunlight, and Vitamin D levels in people are also responsible in how these diseases spread.
- In addition, it is not very clear how much transmission happens through surfaces (as against human contact, or through air). Most people are of the opinion that only little contamination happens through surfaces. And, that during the rainy season, it would not affect indoor surfaces at all.
Seasons & human behaviour
- Viral disease spread depends on three major factors — seasonal changes in environment (temperature, humidity, sunlight), human behavioural patterns, and intrinsic characteristics of the virus, like its infectiousness, pathogenicity and survival.
- For example, spitting on the streets is a common problem that increases the risk of virus transmission. The hope is that rains will wash or dilute this off the streets.
- Also, during rains, people spend an extended period of time within closed spaces, like homes or offices, and there is likely to be a lower number of people in crowded public spaces.