Mangaluru: Now, an engineering student stabbed at Adyar Padavu

Udupi, Jun 1: As many as 73 people have been tested positive for coronavirus in Udupi district today.

The district has registered a total of 260 positive cases so far. Majority of the positive cases in Udupi district have inter-state travel history to Maharashtra.

Mangaluru, May 31:  Even as the worst locust attack on India in recent years raised concerns over its impact on crops, swarms of locusts have triggered panic in Karnataka’s Dakshina Kannada too. 

Farmers in the coastal district were taken aback when they found the swarms of locusts, which they feared as the arrival of desert locusts in the region.

According to reports, Renjalady village under the limits of Nuji Baltila Gramp Panchayats in Kadaba taluk and Shirlalu village in Belthangady taluk witnessed locust attacks in last couple of days. 

“Locust swarms were seen in many areas. We have also alerted agriculture department. Already insects have destroyed crops of many farmers,” said a farmer in Shirlalu village.  

Joint director of Dakshina Kannada district agriculture department MC Seetha confirmed that officials have received information from villagers about the locust scare and entemologists have already visited the place to collect more information.

Not Desert Locusts?

“We contacted entemologists and forwarded the pictures that farmers sent to us. Looking at the picture, entemologists have opined that it may be calotropis locust or colour grasshopper. Desert locusts usually arrive in lakhs,” said Ms Seetha. Desert locusts that are destroying crops in other parts of India may not come to Dakshina Kannada, she added.

The current physical distancing guidelines provided by the World Health Organisation (WHO) and by the US Centers for Disease Control and Prevention (CDC) may not be adequate to curb the coronavirus spread, according to a research which says the gas cloud from a cough or sneeze may help virus particles travel up to 8 metres. The research, published in the Journal of the American Medical Association, noted that the the current guidelines issued by the WHO and CDC are based on outdated models from the 1930s of how gas clouds from a cough, sneeze, or exhalation spread.

Study author, MIT associate professor Lydia Bourouiba, warned that droplets of all sizes can travel 23 to 27 feet, or 7-8 metres, carrying the pathogen.

According to Bourouiba, the current guidelines are based on "arbitrary" assumptions of droplet size, "overly simplified", and "may limit the effectiveness of the proposed interventions" against the deadly pandemic.

 She explained that the old guidelines assume droplets to be one of two categories, small or large, taking short-range semi-ballistic trajectories when a person exhales, coughs, or sneezes.

However based on more recent discoveries, the MIT scientist said, sneezes and coughs are made of a puff cloud that carries ambient air, transporting within it clusters of droplets of a wide range of sizes.

Bourouiba warned that this puff cloud, with ambient air entrapped in it, can offer the droplets moisture and warmth that can prevent it from evaporation in the outer environment.

"The locally moist and warm atmosphere within the turbulent gas cloud allows the contained droplets to evade evaporation for much longer than occurs with isolated droplets," she said.

"Under these conditions, the lifetime of a droplet could be considerably extended by a factor of up to 1000, from a fraction of a second to minutes," the researcher explained in the study.

The MIT scientist, who has researched the dynamics of coughs and sneezes for years, added that these droplets settle along the trajectory of a cough or sneeze contaminating surfaces, with their residues staying suspended in the air for hours.

"Even when maximum containment policies were enforced, the rapid international spread of COVID-19 suggests that using arbitrary droplet size cutoffs may not accurately reflect what actually occurs with respiratory emissions, possibly contributing to the ineffectiveness of some procedures used to limit the spread of respiratory disease," Bourouiba wrote in the study