Scientists are only just starting to unravel why some viruses disappear, while others can linger and cause disease for centuries.

Even though 2021 started with a high dose of positive sentiment around the world, as people hoped for an end to the pandemic that has rocked the world for over a year now, many social media users are starting to have second thoughts regarding vaccines that have already been rolled out in recent weeks, especially those who watched Will Smith's 2007 I'm Legend.

The White House coronavirus task force said there could be a new variant of the virus that evolved in the U.S. and is driving spread, a document obtained by NBC News said.

Anew variant of the coronavirus is spreading across the globe. It was first identified in the United Kingdom, where it is rapidly spreading, and has been found in multiple countries. Viruses mutate all the time, often with no impact, but this one appears to be more transmissible than other variants—meaning it spreads more easily. Barely one day after officials announced that America’s first case of the variant had been found in the United States, in a Colorado man with no history of travel, an additional case was found in California.

Scientists in the UK have just recruited the first participants in the world to be part of a new long-acting antibody study.

Another new variant of the novel coronavirus seems to have emerged in Nigeria, the head of Africa’s disease control body said on Thursday, cautioning more investigation was needed.

The latest on the innovations that will let us go back to normal.

While COVID-19 has ravaged much of the globe, Cambodia has just this week declared its first case of "community transmission". How has it managed to avoid any deaths so far? Could it be that the virus came from bats in this area and the locals have a natural immunity?

Even after recovery, the body continues to improve its antibody response to the coronavirus — perhaps thanks to viral bits hiding in the intestine. As coronavirus cases in the United States and around the world rise, scientists are uncovering hints that immunity for those who have had COVID-19 can last at least six months, if not longer.

A year of scientific uncertainty is over. Two vaccines look like they will work, and more should follow.

New research shows that broad, national dissemination of frequent, rapid COVID-19 tests could turn the tide on the pandemic within weeks, without shutting down schools and businesses. For curbing infection, test turnaround time is more important than test sensitivity.

The Moderna vaccine is 94.5% effective against coronavirus, according to early data released Monday by the company, making it the second vaccine in the United States to have a stunningly high success rate. "These are obviously very exciting results," said Dr. Anthony Fauci, the nation's top infectious disease doctor. "It's just as good as it gets -- 94.5% is truly outstanding."

Measures to reduce the spread of COVID-19 through non-pharmaceutical interventions (NPIs) such as mask wearing and social distancing are a key tool in combatting the impact of the ongoing coronavirus pandemic. These actions also have greatly reduced incidence of many other diseases, including influenza and respiratory syncytial virus (RSV).

Why did Japan largely contain COVID-19 despite famously jam-packed Tokyo and despite the country's proximity to China? With no penalties and only requests for cooperation, Japan's state of emergency somehow averted the large-scale outbreaks seen elsewhere. At least one viable answer has now emerged.

Denmark will get rid of its entire mink population over reports the animal had infected humans with a mutated strain of COVID-19.

A study of the lungs of people who have died from COVID-19 has found persistent and extensive lung damage in most cases and may help doctors understand what is behind a syndrome known as 'long COVID', in which patients suffer ongoing symptoms for months.

A study involving more than 5,000 COVID-19 patients in Houston finds that the virus that causes the disease is accumulating genetic mutations, one of which may have made it more contagious. According to the paper published in the peer-reviewed journal mBIO, that mutation, called D614G, is located in the spike protein that pries open our cells for viral entry. It’s the largest peer-reviewed study of SARS-CoV-2 genome sequences in one metropolitan region of the U.S. to date.

It has been almost 10 months since the first case of COVID-19 was reported in Wuhan, China. Since then, countries around the world have been working tirelessly to try and contain the virus that has killed over one million people and infected over 40 million worldwide to date, according the Johns Hopkins University.

A Covid-19 vaccine candidate being developed in China has been found to be safe and to trigger an antibody response, early results have shown. Researchers said those aged 60 and over were slower to respond to the BBIBP-CorV vaccine, but they said it was "encouraging" that the vaccine did trigger such a response. They also found antibody levels to be lower in those aged 60 to 80 years, compared with those aged 18 to 59.

Study team says Covid-19 patients in intensive care should be asked about hearing loss