Dangerous strains of 'hypervirulent' superbug detected in US and 15 other countries

Dangerous new strains of a "hypervirulent" superbug have been found in 16 countries, including the United States, the World Health Organization (WHO) announced in a new report.

The superbug, known as hypervirulent Klebsiella pneumoniae (hvKp), is a type of drug-resistant bacteria that can cause rapidly progressing, deadly infections, even in people with Healthy immune systems.

In general, K. pneumoniae can be found in the environment — for example, in soil and water — as well as in the upper throat and gastrointestinal tract of various Animals, including humans. The classic version of the germ is a big problem in Health care settings, where it can contaminate medical equipment and cause opportunistic infections, especially in people with weak immune systems. It's known to cause pneumonia, urinary tract infections, bloodstream infections and the nervous-system infection meningitis.

At baseline, the bacteria are inherently resistant to the antibiotic ampicillin, and in recent years, they've developed resistance to more and more drugs.

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The newer, "hypervirulent" variety of K. pneumoniae poses a wider threat because it can cause severe infections even in people with healthy immune systems. The invasive infections can progress very quickly, spurring a high rate of complications and death, according to CIDRAP News, which is published by the University of Minnesota.

When these hvKp strains were initially discovered in Asia in the 1980s, they were still vulnerable to a variety of antibiotics. But now, the strains have spread globally and show resistance to both older and newer classes of antibiotics, studies suggest. In particular, it's concerning that some of these strains show resistance to carbapenems, a class of antibiotics often used to treat bacterial infections that are resistant to multiple other drugs.