Tag Archives: COVID-19 pandemic

Signs of Unusual Symptoms Spread on Twitter Well Before Official COVID-19 Reports

People in Europe were tweeting about a “dry cough” more than usual as early as January 2020, newly analysed data reveal. While social media has played a key role in disseminating health information during the relentless COVID-19 pandemic, the new findings show it has the potential to be useful in other ways, too. Authorities could be using such platforms to obtain real time, localised information about emerging viral hotspots before they’re detected by official means, statistician Milena Lopreite from the University of Calabria and colleagues suggest in their new study.

Our study adds on to the existing evidence that social media can be a useful tool of epidemiological surveillance,” said economist Massimo Riccaboni from IMT School for Advanced Studies Lucca.

They can help intercept the first signs of a new disease, before it proliferates undetected, and also track its spread.”

Within a dataset of over 570,000 unique users and more than 890,000 tweets, Lopreite and team searched for tweets from seven European countries with keyword “pneumonia” (in seven European languages) from last winter, and compared them with previous winters as far back as 2014. After excluding links to news to take out mass media coverage, they found a significant increase in their keyword in most of the countries during the 20190-2020 winter, compared to previous years. They repeated this with other terms for common COVID-19 symptoms like “dry cough” and once again found similar patterns.

For Italy, the tweets showed signs of brewing virus hotspots in the first week of 2020weeks before the first case was officially announced on 20 February 2020. A similar pattern was seen in France. For Spain, Poland and the UK this social signal of COVID-19‘s presence appeared two weeks before their official cases. These findings show just how much of a delay there can be between the presence of a new disease and our detection of it.

What’s more, “whistleblowing came primarily from the geographical regions that turned out to be the key breeding grounds for infections,” the researchers explained in their paper.

By integrating this information with data on environmental drivers like pollution, social media could prove a powerful tool for tracking new outbreaks, the team recommends. Lopreite and colleagues note that this strategy is not a forecasting tool for unknown new diseases, because we do need to understand enough about the disease first – to know what to look for. However, it could be a useful tool for tracking new waves of COVID-19 that are likely to arise once restrictions like social distancing are lifted around the world.

Source: https://www.sciencealert.com/

How Does an mRNA Vaccine Work?

The COVID-19 pandemic has brought unusual attention to everything from handwashing to polymerase chain reaction (PCR) tests. As we move into the later stages of this pandemic, though, a different scientific concept has dominated the national conversation: vaccines. The study of the human immune system and how vaccines influence it is complex and sometimes counterintuitive, and the deployment of a new method for immunization based on mRNA has made it all the more confusing.

The two vaccines that have received Emergency Use Authorizations (EUAs) from the Food and Drug Administration are both mRNA vaccines. And since they’re our only hope for ending this pandemic, it’s crucial to understand how they work—and why you should get one.

Vaccines come in a few main forms, but they share the same central goal: equip our immune systems with the tools to handily defeat a pathogen we might encounter in the future. Think of it like a practice round before your body sees the real thing.

The exact way our bodies develop this preemptive immunity depends on the kind of vaccine we’re given. Live-attenuated vaccines provide our cells with a weakened version of a pathogen; protein subunit vaccines give just one part of a bad guy, so immune cells know how to recognize that part of a virus or bacterium. But mRNA (short for messenger RNA) vaccines actually provide our cells with the instructions for making a protein from the pathogen, in essence creating their own practice dummy. Our own cells produce the viral protein specific to, say, SARS-CoV-2, and then our immune system learns to recognize the proteins.

Source: https://www.popsci.com/

Innovative Universal Flu Vaccine

For epidemiologists, the COVID-19 pandemic has greatly intensified their long-standing nightmare about another virus: the emergence of a new and deadly strain of flu. A universal flu vaccine, effective against any strain of the influenza virus that can infect humans, could protect us from this peril, but progress has been slow. A novel concept for one universal vaccine candidate has now passed its first test in a small clinical trial, its developers report today in Nature Medicine.

Seasonal flu vaccines induce antibodies against the “head” (slate) of the influenza surface protein hemagglutinin, but a new universal vaccine triggers antibodies (fragments of them shown in gray) that bind to the stalk (light blue) portion

This is an important paper,” says Aubree Gordon, an epidemiologist at the University of Michigan School of Public Health who studies influenza transmission and vaccines.

The influenza virus rapidly accumulates mutations and easily “reassorts,” or swaps, genes between strains, creating variants that can dodge any past immunity people had acquired naturally or from vaccines. That’s why a new flu vaccine must be developed each year. Existing flu vaccines contain weakened or inactivated influenza viruses with a mix of hemagglutinins (HAs), the proteins that stud their surfaces. These vaccines primarily aim to trigger antibody responses against HA’s top part, or head. Genetic changes in flu viruses rarely alter most of the head. But a small part of the head does reassort, or mutate, frequently, which allows new viral strains to dodge any immune memory and forces flu vaccinemakers to prepare new formulations each year, with updated HAs.
In the trial, 51 participants received the various vaccines and their antibodies were compared with those of 15 people who received placebos. A single shot of vaccine with chimeric HA inactivated viruses, the researchers report, “induced remarkably high antistalk antibody titers.”

Source: https://www.sciencemag.org/