Dr. Liliana Revolledo: “Salmonella has become a hobby more than a job”
Revolledo has become an expert in avian pathology, Salmonella and regulatory issues in the Latin American area

The Doctor Veterinarian, Liliana Revolledo, completed his doctorate and a master degree at the University of Sao Paulo (Brazil). She has dedicated his professional career to research and teaching related to veterinary science topics. Likewise, she has also specialized in matters related to the registration of feed products. As a result of her experience acquired throughout her long career, Revolledo has become an expert in avian pathology, Salmonella and regulatory issues in the Latin American area.
In this interview we will deepen in her experiences, her point of view regarding the diseases that currently affect both animal production and food health, as well as her opinion on the evolution and state of salmonellosis at present.
- Could you give us a brief summary of your professional career?
I studied Veterinarian Medicine in Faculty of Veterinary Medicine of Universidad Nacional Mayor de San Marcos in Peru. Then, I was in the same Faculty doing a degree, which I could not conclude with a thesis. From 1993 to 1999, I worked for the Servicio Nacional de Sanidad Agraria (SENASA-Peru). During that time, I was in charge of the Directorate of Zoosanitary Defense, which, basically, had two focus of action: the first, international business in live animal products and by-products of animal origin, and the second, the registration of products for veterinarian use, included additives and animal feed.
From 2000 to 2010, I remained in the Faculty of Veterinarian Medicine and Animal Husbandry of the University of Sao Paulo. There I completed a master in Experimental and Comparative Pathology, a Doctorate in Science and a Post Doctorate in the Pathology Department with a research on the development of strains on Salmonella, for the elaboration of live vaccines for prevention.
Since 1993, I have worked especially on the regulatory field with products for veterinary use, which is what I currently work with my consulting company in Brazil, providing services for the entire Latin American region from Mexico to Chile.
You have studies in the field of veterinary sciences, but you are specialized in the topics of Avian Pathology and Salmonella. Why did you choose these subjects?
The interest in Avian Pathology arose during my stay at SENASA. At that stage, I had to be part of the negotiation teams of bilateral or multilateral protocols or norms in the Andean Community, which required additional knowledge of diseases that affect birds. The interest in Salmonella already arose at that time of official activities and increased during my stay at the University of São Paulo, under the guidance of Prof. Antonio J. Piantino Ferreira, from 2000 to 2010. As I say: until today Salmonella has become a hobby more than a job. My current work focuses on the regulatory area, advising companies for the preparation of regulatory plans and licensing processes in Latin America.
- Which pathologies are more common in Brazil?
The diseases are the same as in other countries of Latin America, I have not observed many differences, except for the morbidity and mortality are associated with the huge herds that exist in Brazil. Therefore, the numbers are sometimes proportional to the size of the industries, both poultry and pigs.
- Are there significant differences between the most frequent diseases of years ago and those of today?
I do not think we can call them significant differences. I believe that today there are increasing concerns about the control of some diseases and in food security. Advances in diagnosis and detection procedures have allowed not only a deeper knowledge, but an improvement in the detection of some diseases, especially with the use of molecular techniques.
- ¿What do you consider to be the main infectious diseases that affect human health?
I think that influenza, cholera and yellow fever are the ones I consider the most common in this region of the world. In relation to those associated with food, the current OMS reports said that Listeria and Salmonella are among the two most important.
- And, the pathologies that affect productivity?
I think the list in this question is extensive. I consider that any imbalance, not exactly an infectious disease or an agent, is responsible for the occurrence of diseases. I am convinced that the imbalance in the members of epidemiological triad affects productivity, and that the intervention of man, not only through genetic lines, but through its intervention in production systems, has incorporated an extremely variable ingredient that favours, most of the times, the appearance of diseases that affect productivity.
- ¿What do you think about probiotics?
That they are a very good tool to return the homeostasis in the mucous membranes, and that its usefulness is invaluable if we provide them with the adequate conditions for them to work.
- ¿What did the Biovet award of 2009 for your research in Salmonella mean to you?
An incentive to continue the research about Salmonella and the alternatives for its control in this region of the world.
- Following this award, you Publisher an article on veteriariadigital.com entitled “Salmonella, colonization of the gastrointestinal tract” What’s new in this field?
A lot has been published since 2009 to date, in relation to Salmonella and the colonization of the intestinal tract. Thanks to molecular tools, sequencing and the most recent techniques, which did not exist at the time I studied, today we have been able to identify new genes with virulence determinants that until a few years ago were not known, as receptors in the host, that are directly related to colonization and its interaction with immune phenomena that may be associated with resistance in the host.
- ¿Why do you think it is so difficult to eradicate Salmonella, taking into account that the European Union has a plan for more than 11 years and there is still a 27% mortality in birds due to Salmonella?
Because of the multiple possible sources of the bacteria and, because in the improvement of production there are some ingredients that, although we believe that we control effectively, we have neglected basic elements that have allowed the installation and permanence of the bacteria. In the Nordic countries the levels are very low, however, until today it has not been eradicated and they have been almost five decades in that work. I am convinced that we will have to learn to survive with it and use tools for effective control plans that reduce its presence on farms to the minimum expression.
- How important are coprophagous beetles in the transmission of Salmonella?
Their presence is directly associated to transmission especially when birds eat larvae de Alphitobius diaperinus, which allow a more efficient transmission that adult insects. And, in this case, I would like to highlight that the control of the environment plays an important role in the control of Salmonella, and this control must be not only efficient, but also permanent.
- What is your opinion on the evolution of the aquaculture industry in Latin America, both in the river and in the sea?
I think Chile has been one of the best examples of the region for many years, followed by Ecuador and other countries of the regions.
Likewise, aquaculture has been increasing with some projects in different countries of Latin America. There is a job that we need to do and professionalize, as well as to train qualified professionals, to collaborate efficiently in the growth of this new area.
- You have also worked on the subject of registrations. How is the subject of patents for vaccines in the country?
In Peru we still lack a lot in this area, especially in the area of veterinary vaccines and in other categories of veterinary products. This is an important issue from the point of view of regulation and protection of the development or discovery of new molecules. However, patents and ethics are two words that must go hand in hand. We still have a lot to learn.
- You collaborate with CAMEVET (Committee of the Americas on Veterinary Drugs)?
Yes. I collaborated in a training project for which last year a commission of the countries was formed, and I participated in a discussion group to harmonize product registration guides in Latin America. It is an active group, very interesting, although, personally, I would like it to be more proactive.
- What is your opinion about the integration of the legislation of additives, drugs, vaccines in Latin America countries?
It seems to me that there is a lack of updating, and that the regulations should not only be transparent when required by manufacturers or importers, but also in the evaluation processes by the regulatory authorities. The regional regulations are very good, although due to the participation of many members and countries there are delays that sometimes do not allow specific work in this area.
One example is my participation as consultant of the Andean Community of Nations (CAN for its abbreviation in Spanish) in 2012 for the elaboration of a “Manual for the application of a new norm on veterinary products”, Resolution 769. To date, the norm is not applied due to the lack of approval of the manual, which was concluded with the participation of all the countries of the CAN. I am convinced that there should be no differences between countries, the legislation is not different in essence, and the products must meet with the same requirements. However, I believe that there is still a lack of “willingness” for this process of regional integration, as the European Union has done, to be successful.
As a teacher, how do you assess the status of veterinary studies?
I believe that an updating of the content is missing, at least in Peru and in most of the countries in the region. There are many areas, especially those linked to government work, where the Veterinarian has a wide field, which is not explained in an applied way within the veterinary courses, and this is essential today.
- What has been the evolution of these studies in the last 10 years?
There has been some evolution due to the new tendencies in the different areas, especially the applied ones; the new techniques are a sample of it. However, I think we could do more. Our commitment to future generations requires important changes, and that is what our focus should be in the next decade.
- What challenges remain to ensure that qualified professionals leave the classroom?
Many. First, the contents of the career must be updated periodically according to the new trends; second there must be a prior evaluation of the professors in the universities, not always a professional who is a scholar in an area successfully transmits his knowledge to the students. I think this is one of the problems we have in the training of new qualified professionals. Finally, the evaluation models that currently exist should be analysed and eventually replaced, since although they show (in some way) the level of learning obtained, they do not reflect it in an integral way.
- What would you say to future veterinarians?
That ethics is always the main ingredient in their day to day, in their commitment to the profession they chose.
- How do you see teaching and research? Do you think it can be combined?
It seems to me that for teaching we still need to be educators (in the broadest sense of the word) and for research we lack not only resources as defined guidelines. Research is a wide and wonderful area, which has no limits, we lack incentive and in the training of professionals “research is not an alternative”. I think we have much to learn in the region of countries like Brazil or Mexico that, although they have difficulties, still invest in both basic and applied research and train researchers.
In summary, I think it could be combined, however, I believe that good researchers are not necessarily good teachers and vice versa.