Danger from the emergence of new viruses

China identified 35 people infected with a new virus surnamed Henipa, named Langya, or LayV, on August 3. The virus is believed to have originated in shrews, which do not appear to be capable of human-to-human transmission. Thanks to the early warning system, scientists knew about the virus before it became a serious epidemic.

However, experts say the community should not be caught off guard. LayV is just one of many viruses that spread from animals to humans. About 60% to 75% of infectious diseases today are of animal origin. Many scientists predict that the next epidemic is also a virus that spreads from animals to humans and this is the biggest threat to humanity.

As the Earth warms, humans enter wild habitats, animals have to migrate, and will come into close contact with new species. This provides an opportunity for pathogens to adapt and evolve, eventually spreading to humans. Recent reports show that in a warming scenario, 15,000 new viruses will emerge among 3,000 mammals by 2070.

Some diseases that are transmitted from animals to other people are notable, such as monkeypox and Covid-19. Many diseases that do not originate from animals, seemingly dormant for decades, suddenly arise, such as polio, becoming a wake-up call, providing lessons for the whole world.

nCoV is the newest strain in the corona virus family.

In July, the US reported its first case of polio in nearly a decade in an Israeli woman who had been paralyzed since March. The virus was also found in sewage in London, England, leaving all children under 10 age to be vaccinated.

It's a worrying situation, especially as a New York health official warned the area could have hundreds of undiagnosed cases of polio.

As for monkeypox, the US has declared a public health emergency. In theory, the country has all the right tools to prevent the spread of the disease such as tests, treatments and vaccines. However, all are surprisingly limited.

The supply of the Jynneos vaccine that prevents monkeypox is not nearly enough to cover those most at risk of contracting the disease. Therefore, the country adopts a new strategy, which has been approved by the US Food and Drug Administration (FDA). People will be given a smaller dose of the vaccine, one-fifth of the usual dose, injected on the surface of the skin instead of under the skin. Thus, the remaining 440,000 doses of vaccine will provide 2.2 million injections.

The problem is that the strategy is based on a single study, published in 2015. If the US is to really go ahead with the plan, health officials need to prove the vaccine is still effective, according to Lisa Jarvis, a Bloomberg health expert. results at low doses.

Meanwhile, Covid-19 continues to break out in many places because of a new strain. Scientists still can't explain this phenomenon, but this is the question that needs to be answered as the world enters winter. The theory is that the virus spreads like a wildfire, self-extinguishing when it runs out of fuel. When most people have acquired immunity from natural infection or vaccination, the epidemic can temporarily cease to be contagious.

In fact, herd immunity is only a seasonal protective barrier. Population behavior and demographics are the wall to prevent the epidemic from returning. Scientists are working to collect data from wastewater and surveillance testing to get a clearer picture of why the Covid-19 waves are constantly rising and falling, in order to completely prevent the next outbreak. follow.

However, experts say that Covid-19 has now reduced its danger. Sewage studies show that the virus is still infecting on the same scale as last winter, but with far fewer deaths and hospitalizations. The US Centers for Disease Control and Prevention (CDC) is relaxing its epidemic prevention guidelines, no longer recommending that adults and children self-isolate after being exposed to the source of infection.

Meanwhile, scientists still have to watch for the next pathogen that will emerge, whether it is a new strain of nCoV, or an old virus resurfacing or a completely new virus.