Did weather change also lead to COVID-19 spike?

Though a lot of research is yet to be undertaken about the behaviour of the novel coronavirus (COVID-19), and epidemiologists have different views, a few epidemiologists in Hubballi, who are into community medicine, have somewhat a similar opinion that with lockdown and other precautionary measures, along with summer season also, might have contained COVID-19 spread to some extent initially.

However, it boosted the spike later probably due to cold weather and humidity with the onset of monsoon preceded by 'Nisarga' cyclone effect, mainly along with huge influx of migrants from other States, they feel.

"Due to high temperature in summer, the life of virus in air is less, when it is released from the human body. During more cold and humidity, it stays longer in air and hereby gets more chance to get transmitted to another living body. Now, the weather has changed, and lockdown is relaxed," observed Karnataka Institute of Medical Sciences (KIMS) Community Medicine Department head D D Bant.

However, another community medicine expert Manjunath Nekar says that there is still confusion on whether the virus spread may be more with more humidity, but this is a speculative possibility.

During the peak summer on May 1, the number of total COVID-19 cases in the State stood at 589, with 99 cases in previous one week. After 'Nisarga' cyclone effects started in May last week, total cases were 3,408 on June 1, and fresh cases on that day was 187. After monsoon began, there seems to be been a spike in the cases, and fresh cases were 416 on June 20, and total number of cases was 3,691. But, discharged cases in the State are more than active cases.

But, several doctors say that more research about the effect of cold weather on the virus spread has to be conducted.

'Cold affects'

Noted physician G B Sattur is firm that cold weather definitely increases the spread of COVID-19, as it is just like any another flu virus, while more coughing, less social distancing, and less ventilation in houses take place during the rainy season.

"Extreme heat does not kill COVID-19 virus, but cold weather may make it spread more, while common flu may also be mistaken. It seems to have reached community spread level, and its spread will come down when herd immunity level is developed," Dr Sattur said.

When peak?

Several epidemiologists and medical practitioners predict that the peak of COVID-19 spread may reach in two-and-a-half months, and will come down later.

"Virus has a natural cycle, and after reaching its peak of spread, it has to flatten. People also have more responsibility now," Sattur said, adding that the Indian Council of Medical Research (ICMR) should also approve more private laboratories and hospitals for testing and antibody treatment.

'Poor planning'

A epidemiologist was of clear opinion that planning to manage the pandemic in India was poor at the initial stage.

"Only politicians and bureaucrats took major decisions, instead of brainstorming with major epidemiologists and taking their suggestions, as done in countries like Sweden. Firstly, all international passengers should have been tested with rapid kits at arrival, and should have been quarantined," he said.

An epidemiologist who was trained by the World Health Organisation (WHO) and also worked at Dharavi in Maharashtra, opines that Hydroxychloroquine (HCQ) tablets should have been given to many people in Maharashtra, to reduce Cocid-19 load in Karnataka from those who came from Maharashtra. Careless migration, some confusions in management, and climate change also resulted in the spike in cases here, he opined.

A short-term lockdown, and containing virus spread by the active cases which have become less now can bring the situation down in two months, he added.