Rutgers researchers develop method to detect viruses in mosquito droppings

Researchers at Rutgers University (United States) have developed a system capable of analyzing mosquito excrement to detect viruses, parasites and other microorganisms present in the environment, a technique that could strengthen early warning systems against emerging diseases and possible epidemics, according to sources from the center itself.

The method is based on a collection device designed using 3D printing that allows capturing small droplets of waste produced by insects. Scientists then sequence all the genetic material contained in the samples to identify the organisms present. The technique could reinforce the surveillance of vector-borne diseases and possible emerging zoonoses, by allowing the early detection of viruses that circulate among animals, mosquitoes and other organisms in the environment.

During the tests, carried out with 100 wild mosquitoes of the genus Culex captured in New Jersey (USA), the researchers managed to reconstruct a complete genome of the West Nile virus, the main disease transmitted by mosquitoes in the region. In addition, they detected for the first time in America a virus similar to the one called Hedwig and found several genetic sequences that could correspond to viruses still unknown to science.

According to the authors, the main advantage of this strategy is that it allows us to search for known and unknown pathogens simultaneously, without the need to start from a prior list of threats. This is different from conventional surveillance methods, which require capturing, classifying and analyzing mosquitoes individually or in groups.

The researchers stressed that the technique is still in the experimental phase and does not replace current epidemiological control systems. However, they are working on the development of autonomous traps capable of collecting samples, analyzing them and transmitting the results in real time.

Arthropod vectors of infections

According to the team of virologists, led by Dana Price, about 30% of emerging infectious diseases detected in the world are transmitted by arthropod vectors, such as mosquitoes, and their weight continues to increase due to factors such as climate change, urbanization, human mobility and global trade. In this context, they maintain that the early detection of pathogens in mosquito populations can offer a warning signal before human cases appear and facilitate a faster response from health authorities.

Price and his colleagues highlighted that current surveillance methods typically look for specific viruses using targeted testing, which requires knowing in advance which pathogen to detect. Their proposal, based on the massive sequencing of the genetic material present in mosquito excrement, instead makes it possible to simultaneously track known viruses, emerging variants and unknown microorganisms. In the opinion of the researchers, this capacity could be especially useful "to monitor pathogens of interest to the One Health approach, many of them originating from zoonotic cycles between wild animals, vectors and humans."