When SARS-CoV-2 virus began spreading globally early last year, Singapore, Vietnam, Taiwan, South Korea, Hong Kong, Australia and New Zealand, like mainland China, adopted a “Zero COVID” strategy. A few countries have already abandoned this strategy with the Delta variant changing the ground reality. When SARS-CoV-2 virus began spreading globally early last year, Singapore, Vietnam, … Continue reading Why countries have abandoned the ‘Zero Covid’ strategy
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India will add four million more cases by May 1, says Giridhara Babu
A small proportion of the population might have reinfections due to waning antibodies. With newer areas seeing the surge in cases, we cannot rule out older variants spreading to these areas. There may be a dual problem facing the country. The old and newer variants might be in circulation in the uninfected regions in an … Continue reading India will add four million more cases by May 1, says Giridhara Babu
What is driving the second wave in India?
Understanding the infectiousness of the double mutant variant becomes all the more important as noncompliance to COVID-19 appropriate behaviour is uniformly poor across India. Yet, the surge in cases is seen only in 19 States, and mainly in about a dozen States. In the absence of timely results of such studies, which will help policy … Continue reading What is driving the second wave in India?
Are the variants causing a spike in cases in India?
What is causing the new spike in four States after a steady drop in cases since mid-September last year despite the much-feared festival season, winter, large gatherings, almost absent restrictions in the free movement of people across States and national borders, and not-so-good adherence to mask wearing? After a peak of nearly 98,000 fresh daily … Continue reading Are the variants causing a spike in cases in India?
Is the first coronavirus wave coming to an end in India?
The number of daily fresh coronavirus cases has been steadily dropping from a peak of nearly 98,000 cases on September 16 to below 25,000 daily cases in the last few days with no spike seen nationally. The cases have been reducing despite the festival season, winter, large gatherings and not so good adherence to non-pharmaceutical interventions. However, the cumulative test positivity rate nationally is 6.1% as on December 23, which suggests we aren’t near the end of the first wave immediately.
Three studies document in-flight transmission of coronavirus
While in-flight transmission of novel coronavirus among passengers is considered to be low, three studies have found instances where coronavirus transmission had probably taken place in-flight. The spread has probably become possible as mask wearing was not compulsory early in the pandemic. But thermal imaging, which has been in place since the beginning, has been found wanting.
Finally, CDC acknowledges aerosol as the ‘main way’ of coronavirus spread
On September 18, CDC revised its guidelines to acknowledge that the “main way” the novel coronavirus (SARS-CoV-2) spreads is through aerosols. It also for the first time mentions that virus can spread through breathing, stay suspended in air and travel to distances beyond six feet.
Can universal masking be a crude ‘vaccine’?
Universal mask wearing decreases the chance of infection and, if infected, decreases the amount of virus particles (inoculum) a mask-wearer is exposed to thus causing only asymptomatic infection or mild COVID-19 disease.
Two-layered polypropylene mask doubly better than a single-layered cotton mask, study finds
While fitted N95 masks allowed zero droplets to pass through, the three-layered surgical masks too performed very well with 0-10% droplet transmission. N95 masks with exhalation valve fared poorly. Double-layered cotton masks were better that single-layered ones. Finally, the efficiency of N95, surgical masks and 12 other masks made of different materials to reduce droplet … Continue reading Two-layered polypropylene mask doubly better than a single-layered cotton mask, study finds
Is there a case for issuing immunity certificates to COVID-19 recovered people?
While there is a clear case for ‘immunity passports’ with some restrictions for people who have recovered from COVID-19, the issue of handing out such certificates is an ethical minefield. It has a dangerous public health risk too as it will encourage people to indulge in risky behaviour in order to get infected. As on … Continue reading Is there a case for issuing immunity certificates to COVID-19 recovered people?
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