If measures are not taken now, in 2050 more than ten million people in the world will die each year from multi-resistant bacteria , according to a study prepared by the KPMG consultancy at the request of the British Government.
On the other hand, a document from the World Bank Group (made up of 189 countries) indicates that, by that date, drug-resistant infections could reduce world GDP by between 1.1% (in a so-called low-impact scenario) and 3.8% (in the high-impact one). The worst affected would be poor countries, both in the number of victims and in the economic cost.
This global emergency forces us to look for new tools against superbugs with which current drugs can no longer. This was explained by Ennio De Gregorio, head of the Vaccine Research Center of the pharmaceutical company GSK in Italy, at the meeting How vaccines can combat antimicrobial resistance , which was held at the end of last November in Siena. The scientist was clear: “ Vaccines are essential in the fight against antibiotic resistance, because a single medical strategy is no longer enough. They prevent infections, which reduces the circulation of bacteria and, therefore, the use of antibiotics that fight them, but they also make them evolve and gain resistance ”.
The case of tuberculosis
The efficacy of vaccines against strengthening bacteria is being investigated in the microorganism that kills the most: Mycobacterium tuberculosis , responsible for most cases of tuberculosis. According to the WHO, in 2018 1.5 million people died from this infection, and it is estimated that a quarter of the world’s population carries the bacteria.
10% of carriers will develop pulmonary tuberculosis, especially in undeveloped countries, where access to diagnostics and drugs is very limited. Multi-drug resistant strains of Mycobacterium tuberculosis are emerging and spreading throughout the world. The only vaccine (available since 1921) is BCG, which takes its name from the modified bacterium that constitutes it: the Calmette-Guérin bacillus. But it does not provide proven and consistent protection to adults in states plagued by endemic tuberculosis.
Recently, GSK brought hope by announcing that a clinical trial done with its experimental M72 / AS01E1 vaccine significantly reduced the incidence of the disease in latently infected adults (carriers of the bacteria who have not yet developed the disease). This vaccine is not applicable to patients with HIV.
The New Delhi enzyme
There are other cases that demonstrate the great danger of resistance to antimicrobial drugs. One of the most worrisome is that of the New Delhi enzyme or NDM-1, which makes the bacteria that possess it almost immune to antibiotics, including those of the carbapenem family, the main therapeutic weapon against resistant strains. This enzyme has caused alarm in Tuscany in the last year: more than a hundred people have been infected there by different bacteria made multi-resistant by this protein.
The mortality rate caused by microorganisms with NDM-1 ranges between 30% and 40% 30 days after infection. This enzyme was first identified in 2008 in a Swedish patient from New Delhi. Experts raised the alarm when the enzyme began to be detected in one in ten strains of Escherichia coli , one of the most common bacteria in humans.
By Sandra Pulido
