News and Views

The successful uptake of any vaccine for Covid-19, a crucial step in returning a sense of normalcy after a year ravaged by the coronavirus pandemic, could be hindered by widespread contamination from a range of chemicals used in everyday products. Small amounts of per- and polyfluoroalkyl ( or PFAS ) chemicals are commonly found in the bodies of people in the US, as well as in several other countries. These man-made chemicals,  used in everything  from non-stick pans to waterproof clothes to pizza boxes, have been linked to an elevated risk of liver damage, decreased fertility, and even cancer. But scientists warn some of these chemicals can also cause another little-known but potentially significant defect by reducing the effectiveness of certain administered vaccines. This impediment could cast a shadow over efforts to roll out a Covid-19 vaccine to enough people that restrictions on day-to-day life are eased. Source: https://www.theguardian.com/world/2020/nov/17/chemicals-f...

Within any population, there is genetic variation. Viruses are no different. Some versions of the virus will be very slightly more dangerous to human health – more virulent – others less so. If the conditions are right, the slightly more virulent ones will begin to predominate and cause more damage.  A pathogen, or disease-causing organism, does not “want” to kill its host. Its only evolutionary goal is to survive and reproduce, and if it has to kill to achieve that aim, then so be it. It causes harm because it needs its host’s cellular machinery to replicate and transmit to a new host. We feel sick because it’s siphoning off our bodily resources, and because of our own immune response. When a novel pathogen emerges in humans, having jumped from an  animal reservoir , it is not adapted to us. If it is too virulent, it risks immobilizing its host through illness or death before it can spread to a new one; not virulent enough, and it’s a weak transmitter – another evolutionary d...