Effect of preventive measures in the containment of SARS-CoV-2 epidemic: a comparative study.

From the time when the first cases of COVID-19 were reported in Wuhan City, China, in December 2019, strict regulations are being implemented by policy makers to contain the spread of the virus. The measures taken in different countries spanned from complete isolation and lockdown to different degrees of restrictions to people's movement, contact between people, hygiene and sanitation. Accordingly, the success in containing the virus also differed. Italy was one among the worst-affected countries in the world despite the lockdown measures adopted. A combination of lockdown and Level-3 State of Emergency measures were adopted in Portugal and South Africa, which helped to delay and flatten the epidemic curve. The timely application of Level-3 State of Emergency in Mozambique resulted in recording low infection rates. Above all the tripod, orderly movement of people, social distance and hygiene and sanitation is the keystone measure to prevent spread of the virus. However, for successful outcome, the measures have to be tailored to the local context.

Detecting the Zambezi River plume using observed optical properties.

In April 1998 a research cruise was carried out in the Mozambique Channel taking detailed optical, water quality and salinity measurements; the Zambezi plume waters were apparent through strong colour fronts with green waters in the plume and clear blue waters offshore. A good (r2 = 0.76) negative empirical relationship was found between the salinity (S) and yellow substance, represented by the absorption of filtered samples at 440 nm (g440). An empirical relationship was found between the salinity and a reflectance ratio: S(1/2 Zsd) = 37.45-7.07(R555/R490). An optical model in which light absorption is dominated by yellow substance and light scattering by inorganic particles confirms this empirical relationship. This has been applied to a SeaWIFS image to map salinity on the Sofala Bank, demonstrating the potential to remotely determine the distribution of the Zambezi River plume. It is thought that any significant level of chlorophyll would reduce the effectiveness of the above algorithm.