Showing posts with label smallpox. Show all posts
Showing posts with label smallpox. Show all posts

Monday 10 May 2021

Vaccine hesitancy is nothing new. Here’s the damage it’s done over centuries

“Vaccine hesitancy has less to do with misunderstanding the science and more to do with general mistrust of scientific institutions and government,” says Maya Goldenberg, a philosophy expert at the University of Guelph, Ontario, who studies the phenomenon. Historically, people harmed or oppressed by such institutions are the ones most likely to resist vaccines, adds Agnes Arnold-Forster, a medical historian at the University of Bristol in England.

‘A range of recurring and intersecting themes have fueled hesitancy globally and historically. These include anxiety about unnatural substances in the body, vaccines as government surveillance or weapons, and personal liberty violations. Other concerns relate to parental autonomy, faith-based objections, and worries about infertility, disability or disease. For example, some people oppose vaccines that were grown in cell culture lines that began from aborted fetal cells, or they mistakenly believe vaccines contain fetal cells. One of today’s false beliefs — that COVID-19 vaccines contain a microchip — represents anxiety about both vaccine ingredients and vaccines as a surveillance tool.’

Read here (Science News, May 11, 2021)

Monday 18 January 2021

Vaccines need not completely stop Covid transmission to curb the pandemic

‘Influenza may provide the best blueprint of what to expect going forward. The most common flu vaccine—the inactivated virus—is not “truly sterilizing because it doesn’t generate local immune response in the respiratory tract,” Crowcroft says. This fact, coupled with low immunization rates (often shy of 50 percent among adults) and the influenza virus’s ability to infect and move between multiple species, enables it to constantly change in ways that make it hard for our immune system to recognize. Still, depending on the year, flu vaccines have been shown to reduce hospitalizations among older adults by an estimated 40 percent and intensive care admissions of all adults by as much as 82 percent.

‘Research on seasonal coronaviruses suggests that SARS-CoV-2 could similarly evolve to evade our immune systems and vaccination efforts, though probably at a slower pace. And data remain mixed on the relationship between symptoms, viral load and infectiousness. But ample precedent points to vaccines driving successful containment of infectious diseases even when they do not provide perfectly sterilizing immunity. “Measles, diphtheria, pertussis, polio, hepatitis B—these are all epidemic-prone diseases,” Crowcroft says. “They show that we don’t need 100 percent effectiveness at reducing transmission, or 100 percent coverage or 100 percent effectiveness against disease to triumph over infectious diseases.”

Read here (Scientific American, Jan 18, 2021)

Worst ever Covid variant? Omicron

John Campbell shares his findings on Omicron.  View here (Youtube, Nov 27, 2021)