结核杆菌 z-bio 2021-09-19 421

　　Tuberculosis (tuberculosis) is one of the most persistent and deadly infectious diseases in the world. As a result, between 1 and 2 million people die every year.

　　Scientists who study tuberculosis have been discussing the origin of tuberculosis. According to the latest research, tuberculosis can be transmitted from humans in Africa to seals and sea lions. These animals bring bacteria to South America, where they infect indigenous people. Since then, Europe has landed on the European continent and been infected. This disease.

　　The results of this study were published in Nature on August 21. write

　　The article's Professor Anne Stone of Human Evolution and Social Evolution at Arizona State University said: Sea Lion. \"

　　This discovery surprised us. There is a difference in human adaptation between ancient and modern tuberculosis strains," Stone said. A thousand years ago, the Peruvian genome clearly showed that Mycobacterium tuberculosis caused tuberculosis among locals before Europeans arrived in South America. Therefore, The question facing scientists is, "What type of tuberculosis was before exposure? "

　　In this study, the researchers spent five years collecting genetic samples from all over the world and using advanced genome sequencing technology to complete the DNA detection of Mycobacterium tuberculosis. At the same time, more accurate genome sequencing was performed on ancient samples.

　　Of the 76 samples before and after the formation of the New World, 3 samples contained Mycobacterium tuberculosis DNA in Peru (750-1350 AD). The researchers focused on these three samples and captured them with a chip. Complete genome.

　　compared the modern genome with the animal and flora database. By doing so, the researchers found a clear animal-related lineage, in which lizards and lizards are closely related.

　　"Our research results show that humans are infected with Mycobacterium tuberculosis. It was spread by pinnipeds (sea lions and lizards) before the Colombian era. In the past 2500 years, marine animals have been infected with bacteria from African hosts. These The bacteria has crossed the ocean. “It may have been brought to South America,” Stone explained. The Department of Public Health and the Institute of Animal Health and Veterinary Medicine surveyed 9 cats infected with tuberculosis in Berkshire and Hampshire in southern England. We investigated 24 people who had been in contact with these cats as a tuberculosis screening. As a result, two people were diagnosed with “active tuberculosis” with active disease and started treatment. The other two were “latent tuberculosis”, People who are infected but have not yet become ill. Isolate from the confirmed person. The bacteria found are very consistent with the type of tuberculosis pathogen in the sick domestic cat, and it can be inferred that the patient is infected with the domestic cat.

　　Experts from the Department of Health said that it is extremely rare for domestic cats to be infected with this type of bacteria. Despite the first detection of cats, the aforementioned human transmission cases are still a "very low" public health risk. However, experts also suggest that when a domestic cat is diagnosed with Mycobacterium tuberculosis, people will come into close contact with it. You should have a physical examination and listen to the doctor’s advice.