Why are bats (chiroptera) a preferred host for so many zoonotic diseases? Some of their characteristics (food choices, colonial or solitary nature, population structure, ability to fly, seasonal migration and daily movement patterns, torpor and hibernation, life span, roosting behaviors, ability to echolocate, virus susceptibility, and so on) make them exquisitely suitable. Recent observations of outbreaks and epidemics of newly recognized human and livestock diseases caused by viruses transmitted by various megachiropteran and microchiropteran bats have drawn attention anew to these remarkable mammals. According to literature, 66 viruses have been isolated from bats.
Bats are abundant, diverse, and geographically widespread. These mammals provide us with resources, but their importance is minimized and many of their populations and species are at risk, even threatened or endangered. Whereas other mammals, such as rodents and carnivores, may possess traits in common with bats, such as the ability to hibernate, no group of mammals shares the full suite of attributes that make bats unique.
Bats evolved early and have changed relatively little in comparison with mammals of other taxa. Although the fossil record of bat evolution is incomplete, a recent analysis of 17 nuclear genes dated the origin of chiropterans to the Eocene period (52 to 50 million years ago), coincident with a significant rise in global temperature. The correspondingly ancient origins deduced for certain zoonotic viruses maintained in bats suggest a long history of co-speciation. Viruses that evolved with bats may have used for replication cellular receptors and biochemical pathways which are conserved in mammals that evolved later and which underwent radiation in later geological periods and, therefore, these conserved cellular receptors and pathways could enhance the capacity for transmission of bat-associated viruses to other mammals.
この記事は FRONTLINE の April 10, 2020 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
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この記事は FRONTLINE の April 10, 2020 版に掲載されています。
7 日間の Magzter GOLD 無料トライアルを開始して、何千もの厳選されたプレミアム ストーリー、9,000 以上の雑誌や新聞にアクセスしてください。
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How Not To Handle An Epidemic
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Tragedy on foot
As the COVID-19-induced lockdown cuts the ground beneath their feet in Tamil Nadu, thousands of migrant workers are trudging along the highway to the relative safety of their upcountry homes.
Sarpanchs as game changers
Odisha manages to keep COVID-19 well under control because of the strong participation of panchayati raj institutions and the community at the grass-roots level under the leadership of Chief Minister Naveen Patnaik.
Scapegoating China
As the COVID-19 death rate spikes and the economy tanks in the United States, Donald Trump and his advisers target China and the World Health Organisation with an eye to winning the forthcoming presidential election.
New worries
Kerala’s measured approach to the pandemic and lockdown has yielded results. But it still has to grapple with their huge economic impact on its economy, which it feels the Centre’s special financial relief package does little to alleviate.
No love lost for labour
Taking advantage of the lockdown and the inability of workers to organise protests, many State governments introduce sweeping changes to labour laws to the detriment of workers on the pretext of reviving production and boosting the economy.
Capital's Malthusian moment
In a world that needs substantial reorienting of production and distribution, Indian capital is resorting to a militant form of moribund neoliberalism to overcome its current crisis. In this pursuit of profit, it is ready and willing to throw into mortal peril millions whom it adjudicates as not worth their means—an admixture of social Darwinism born of capital’s avarice and brutalism spawned by Hindutva. .
Understanding migration
When governments and their plans are found to be blatantly wanting in addressing reverse migration, exercises such as the Ekta Parishad’s survey of migrant workers throughout India can be useful to work out creative long-lasting solutions.
Waiting for Jabalpur moment
The Supreme Court’s role in ensuring executive accountability during the ongoing lockdown leaves much to be desired. Standing in shining contrast is the record of some High Courts.
An empty package
The Modi regime, which has been unable to control the COVID-19 infection, restore economic activity and provide relief to millions exposed to starvation, trains its sights on Indian democracy, making use of the panic generated by fear and a lockdown that forecloses paths of resistance.
