A new study of more than a half-million people in India who were exposed to the novel coronavirus suggests that the virus’ continued spread is driven by only a small percentage of those who become infected, known as superspreaders. The study also found that children and young adults are potentially much more important to transmitting the virus than previously thought. The paper is the largest COVID-19 contact-tracing study to date.
Converging lines of evidence indicate that SARS-CoV-2, the coronavirus responsible for the COVID-19 pandemic, can pass from person to person in tiny droplets called aerosols that waft through the air and accumulate over time. An international group of 237 clinicians, infectious-disease physicians, epidemiologists, engineers, and aerosol scientists have published a commentary in the journal Clinical Infectious Diseases that urges the medical community and public health authorities to acknowledge the potential for airborne transmission. They also call for preventive measures to reduce this type of risk.
Study shows that field rats sold in markets and restaurants of Southeast Asia harbour multiple coronaviruses, a study shows. The proportion of positives increased as live animals were moved from “field to fork”, suggesting they were picking up viruses in the process. The strains detected are different from Covid-19 and are not thought to be dangerous to human health. However, scientists have warned that the wildlife trade is an incubator for disease. The mixing of multiple coronaviruses, and their amplification along the supply chain into restaurants, suggests “maximal risk for end consumers”.
Link to study: https://www.biorxiv.org/content/10.1101/2020.06.05.098590v1
This study analyzed l data from 311 regions across 116 countries with reported cases of COVID-19 by March 12, 2020, and found that temperature, humidity, and wind speed were inversely associated with the incidence rate of Covid-19. This means that it is likely that as temperature, humidity and wind speed increase the spread of COVID-19 decreases.
Link to article: https://www.medrxiv.org/content/10.1101/2020.03.27.20045658v1
The authors have built human mobility models, for which they are experts, and attach a virus infection dynamics to it. This results in a virus spreading dynamics model. The preliminary model shows that complete lockdown works. About 10 days after lockdown, the infection dynamics die down in the model. Infections in public transport play an important role, they say. The simulations say that complete removal of infections at child care, primary schools, workplaces and during leisure activities will not be enough to sufficiently slow down the infection dynamics.
Link to article: https://www.medrxiv.org/content/10.1101/2020.03.27.20045302v1
This study formulates a conceptual mathematical model on the transmission dynamics of COVID-19 between the frontliners (e.g. healthcare workers, customer service and retail personnel, food service crews) and the general public. The take-home message of this preliminary model is that everyone in the community, whether a frontliner or not, should be protected or should implement preventive measures to avoid being infected.
Link to article: https://www.medrxiv.org/content/10.1101/2020.03.27.20045195v1