Articles from the World

Research shows even animals benefit from social distance to prevent disease            (This is a quoted article) - 12th May 2020

Microorganisms living inside and on our bodies play a crucial role in both the maintenance of our health and the development of the disease. Now researchers at UTSA have uncovered evidence about the importance of maintaining physical distance to minimize the spread of microbes among individuals.

The scientists observed monkeys in the wild to understand what role genetics, diet, social groupings, and distance in a social network play when it comes to the microbes found inside an animal's gut.

"Social microbial transmission among monkeys can help inform us about how diseases spread. This has parallels to our current situation in which we are trying to understand how social distancing during the COVID 19 pandemic and future disease outbreaks may influence disease transmission," said Eva Wikberg, an assistant professor in UTSA's Department of Anthropology who studies the interaction between ecology, behavior, and genetics in primates.

The gut microbiome refers to all the microorganisms inhabiting the digestive tract, starting with the stomach and ending with the colon. Over the past decade, the microbiome has come under more scientific focus because it's believed that an unhealthy gut microbiome can lead to obesity, impaired immune function, weakened parasite resistance, and even behavioral changes.

However, researching microbiomes is difficult because of the variation in microbial composition between individuals. One long-standing question is whether this variation is driven by genetic makeup, diets or social environments.

This research inquiry has been especially hard in wild populations because of the lack of detailed data necessary to tease apart the myriad factors that shape the microbiome.

To find an answer, Wikberg and fellow researchers studied the fecal matter of 45 female colobus monkeys that congregated in eight different social groups in a small forest by the villages of Boabeng and Fiema in Ghana. The scientists saw major differences among social groups' gut microbiomes.

However, individuals from different groups that were more closely connected in the population's social network had more similar gut microbiomes. This discovery indicates that microbes may be transmitted during occasional encounters with members of other social groups.

A similar setting maybe when people come into one-meter proximity of each other at a store. Being in close proximity or accidentally brushing up against someone else may be all it takes to transmit certain microbes.

This study suggests that microbes transmitted this way to help the colobus monkeys digest the leaves in their diet. However, further research is needed to investigate whether this type of transmission yields health benefits, which could explain why different social groups occasionally have friendly between-group encounters.

"Studies of wild animals can teach us a lot about the importance of using interventions, such as social distancing, to ensure a safer community during this pandemic," said Wikberg.

The study's findings are reported in the May issue of the journal Animal Behaviour.

(Article credit - Google)

After recovering from COVID-19, are you immune?    (This is a quoted article) 12 May 2020

As coronavirus spreads across the globe, a crucial question has emerged: After recovering from an infection, are people immune?

This question is important for understanding who can safely go back to work, as well as for understanding how long the worst impacts of the pandemic are likely to last. Because the virus is so new, the answer isn't fully understood. But so far, scientists say, it looks like SARS-CoV-2 probably induces immunity like other coronaviruses. That means that the human body will probably retain a memory of the virus for at least a few years and should be protected from reinfection, at least in the short-term.

"We do not have any reason to assume that the immune response would be significantly different" from what's seen with other coronaviruses, said Nicolas Vabret, an assistant professor of medicine at the Mount Sinai Icahn School of Medicine who specializes in virology and immunology.

Investigations of SARS-CoV-2 so far have suggested, however, that the immune response to the virus also contributes to the devastating effects of the disease in some people.

The immune response to coronavirus

When a virus attacks its first cell in the body, that cell has two jobs to do before it dies, said Benjamin tenOever, a professor of biology at the Mount Sinai Icahn School of Medicine. The infected cell needs to issue a call for reinforcements, sending out a cascade of chemical signals that will activate an army of immune cells to come to battle the invading virus. And it needs to issue a warning to other cells around it to fortify themselves, something it does by releasing proteins called interferons. When interferons land on neighboring cells, they trigger those cells to enter the defensive mode. The cells slow down their metabolism, stop the transport of proteins and other molecules around their interiors, and slow down transcription, the process by which genetic instructions become proteins and other molecules. (Transcription is the process that viruses hijack to make more of themselves.)

In a study accepted to the journal Cell, tenOever and his colleagues found that SARS-CoV-2 appears to block this interferon signal, meaning it messes with the cell's second job. So the first job — the call for immune system reinforcement — works just fine, but the cells in the lungs don't enter defensive mode and so remain vulnerable to viral infection.

"It just keeps replicating in your lungs, and replicating in your lungs and all the while you keep calling in for more reinforcements," tenOever told Live Science.

In many people, even this crippled immune response is enough to beat back the virus. But for reasons not yet fully understood, some people enter a vicious cycle. As the virus keeps replicating, the immune army that arrives in battle it starts doing its job: attacking infected cells, digesting debris and chemicals spewed out by dying cells, even killing nearby cells in an attempt to staunch the damage. Unfortunately, if the virus continues to penetrate lung cells, this army may do more damage than good. The lung tissue becomes hopelessly inflamed; the blood vessels begin to leak fluids into the lung, and the patient begins to drown on dry land. This seems to be the reason that some people become severely ill a couple of weeks after their initial infections, tenOever said.

"At that point, it's not about what the virus has done," he said. "At that point, it's about controlling the severe inflammation."

This cycle is very bad news. But there is a glimmer of hope in the findings. Because the system that calls in the army of immune cells works fine, it seems likely that survivors of COVID-19 will retain immunity to the virus. And indeed, studies have found high levels of antibodies to SARS-CoV-2 in recently recovered patients. Antibodies are proteins made by immune system cells called B cells. They stick around in the blood post-infection and can bind to the virus, either neutralizing it directly or marking it for destruction by other immune cells.

(Credit- Live Science)