A team from the National Administration of Laboratories and Health Institutes (Anlis) “Dr. Carlos Malbrán”, in collaboration with British researchers, managed to map the cholera bacteria that circulated in our country 30 years ago through genomics, which it allows “the health system to generate different preparation and alert strategies according to the circulating strain,” said authorities of that institute.
The work, published this week in the magazine Nature with the name “The genomic aspects of the cholera epidemic in Argentina clarify the contrasting dynamics between epidemic and endemic vibrio cholerae”, was carried out by experts from Malbrán (Enterobacteria and Genomic Platform Service), the School of Hygiene and Tropical Medicine of the University London and the Wellcome Trust Institute of the University of Cambridge.
The axis of the work is, as its name indicates, the contrast between the so-called “endemic” cholera and that which arrived in Argentina, presumably from Peru. Unlike the first, this peculiar lineage of the bacterium had pandemic potential.
“To control and eradicate the epidemic cholera we must understand how epidemics begin, how they spread, how they diminish and finally end,” reads the abstract of the research.
Josefina Campos, scientist from Malbrán, lead author of the research, has been working for five years accompanied by researchers Tomás Poklepovich, Gisela Zolezzi, Marcela Panagópulo, Ma Rosa Viñas, Miriam Moroni and Ma Inés Caffer.
Campos explained to Télam that “this is the first genomic study of this magnitude carried out in a country, where the epidemic and its subsequent period were studied with this level of detail” and indicated that “this was possible thanks to the role of ANLIS Malbrán during the cholera epidemic in the 90s and the historical collection since then “.
The researcher highlighted that “the complete genome sequencing of 490 samples of strains that affected patients from 14 countries in America between 1974 and 2014” could be carried out.
The group of scientists compared the information with that of other lineages that caused cholera outbreaks in other regions of the world, and thus identified that global lineages were responsible for the last two epidemics in the American continent.
One of them was unleashed in Peru in 1991, and expanded in Chile, Bolivia, Paraguay, the North of Argentina in 1992, and almost all of South America.
In Argentina, the epidemic outbreaks continued until 1998, affecting 4,834 people and causing 72 deaths. This epidemic was produced from the introduction of cholera cases from Southwest Africa.
In addition, it was established that cholera also affected Mexico in 1991, but it did so through a lineage of bacteria that had entered by infected people from Southwest Asia.
The other major cholera epidemic was from a lineage that was introduced in 2010 in Haiti and is still continuing.
“Being able to differentiate the lineages of these bacteria -explained the biochemistry to Télam- allows us to distinguish those with epidemic potential from those that are endemic or with habitual circulation. This allows optimizing surveillance and prevention measures for those with pandemic potential, optimizing the resources of the public health system “.
For her part, the technical scientific director of Anlis Malbrán, Claudia Perandones, told Télam that “this work is just one example of how genomics can contribute to epidemiological surveillance by optimizing the management of pandemics, epidemics and outbreaks.”
Perandones underlined that “the importance of this work lies in the fact that it clearly shows that genomics is an extremely useful tool for decision-making in public health.”
In this regard, he specified that “it was classically thought that the sequencing of the genomes of the different pathogens (viruses, bacteria, etc.) had great academic value but that it was not essential knowledge for the implementation of health decisions”.
And he continued: “This study shows that, through genomics, it was possible to discriminate the occurrence of cholera cases in the same period of time, of strains with high transmissibility and virulence and with epidemic potential and cases corresponding to endemic strains they didn’t have that ability. “
“This differentiation – he added – allows the different effectors of the Health system, laboratories of different jurisdictions, health institutions, epidemiologists and authorities, to generate different preparation and alert strategies according to the circulating strain.”
Malbrán’s technical scientific director explained that “this technology is changing the current way of carrying out epidemiological surveillance and monitoring because it allows knowing with absolute precision the origin of epidemics and outbreaks, identifying pathogens that can produce co-infections, predicting the behavior of different pathogens and identify sources of contagion and high risks of transmissibility in real time “.
The specialist concluded that “this knowledge allows health authorities to make decisions with accurate information for each jurisdiction and without delay, guaranteeing quick responses that reduce morbidity and mortality in the population.
In communication with Télam Perandones, he highlighted that “Anlis is a pioneer in its implementation and these results are seen in the management of the current Covid-19 pandemic and were also seen in the recent outbreaks of hantavirus and Streptococcus pyogeness”
Cholera is transmitted through water and food contaminated by the bacterium Vibrio cholerae, and presents with symptoms such as profuse, watery diarrhea and vomiting.
Although today it is easily treatable, today almost 3 million cases of cholera continue to develop per year, claiming 100,000 lives in 47 countries.
There were 7 pandemics in the world, causing millions of deaths.
The current pandemic that began in the 1960s is caused by a single pandemic lineage, 7PET.
As South and Central America recover from the outbreak in Haiti that began in 2010, this pandemic lineage is circular in the world and is the cause of one of the largest global cholera epidemics currently in Yemen.
A WHO Special Group is carrying out a strategic plan that seeks to reduce deaths from cholera by 90% by 2030.
“This is the disease of inequity that affects the poorest and most vulnerable,” WHO Director-General Tedros Adhanom Ghebreyesus said at the time when presenting the plan in Geneva.