Thirty infectious agents found at ground zero of the DANA that could cause epidemics

BarcelonaA study by the University of Valencia has detected around thirty infectious agents at ground zero of the DANA (National Flood Control Center), which caused severe flooding in the Valencian Community in October. All are pathogens, can cause illness in humans, and were detected in environmental samples of water, mud, and soil taken during the first three weeks after the downpours. Some can be fatal, the researchers warn, while others cause nothing more than diarrhea. Researchers will continue analyzing samples from the area for two or three more years, as there are potential risks of individual infections or long-term epidemics. This is intended to facilitate hospital diagnoses and contribute to the improvement of prevention protocols for similar disasters.

The analyses collected in the study, presented by the researchers this Wednesday and published in the journal One Health Various infectious agents have been detected, including viruses, bacteria, parasitic protozoa, and opportunistic amoebas. Groups of transmitting vectors, such as mosquitoes, sandflies, and mollusks, have also been found in the samples. Among the thirty pathogens detected this time, the most abundant is the bacterium. Escherichia coli (E. coli), which can cause diarrhea and vomiting and has been found in other floods elsewhere. Vibrio cholerae, the cause of cholera, although researchers have clarified that this bacteria comes in different forms and that the ones found are wild ones, "low pathogenicity for humans." The most problematic scenario would be if they combine and become more pathogenic.

The microorganisms detected range in transmission, from direct to zoonotic (from animals to humans), and the routes of infection range from oral to transcutaneous through wounds. High rates of fecal contamination have also been found, both human and animal, with potential reservoirs such as sheep, goats, equines, dogs, and cats.

What most surprised researchers was "the qualitative richness of infectious agents," said Professor María Dolores Barques of Parasitology during the presentation of the study. "We didn't imagine we would find so many," she admitted. In samples taken in the first three weeks after the floods, more than 3,500 mosquitoes were captured in four traps placed in different areas, a much higher number than usual between October and November due to the high humidity in the area. However, Barques added that they anticipate that future samples "may contain many more" pathogens.

Impact on residents

The University of Valencia research also includes an experimental study to analyze how the infectious agents detected could affect the area's residents, given that many lived on ground floors, the most affected by the water. In fact, during the press conference, two local residents explained that since the flood,

Professor of Parasitology and World Health Organization (WHO) expert Santiago Mas-Coma explained that the study's intention is to continue analyzing samples taken in the area over the next two or three years, and he assessed that the results will serve to facilitate diagnoses in hospitals, as well as aid the WHO. Regarding equipment, the researchers highlight the importance of the sewage system in the area. For example, the fungi "can disappear if there is a functioning system," said Mas-Coma. The Canary Islands University Institute of Tropical Diseases and Public Health, the University of La Laguna, and the MiniAging group of the Incliva Health Research Institute collaborated. The research was funded by the University of Valencia, the CIBER network for Infectious Diseases of the Ministry of Health, and the Prometeo Project of the Valencian Government and the island of Tenerife.