A Tribute to Margarita Ostrowski de Núñez
Discover the inspiring story of Margarita Ostrowski de Núñez, a pioneer in helminthology who advanced science with passion, resilience and precision.
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Margarita Ostrowski de Núñez was a distinguished biologist whose work significantly advanced our understanding of parasitic worms. Her exhaustive research is marked by meticulous descriptions of their morphology, life cycles and host-parasite relationships.
Born in Buenos Aires, Argentina, in 1938, Margarita was the daughter of German immigrants. Her father, a pastor in the German Evangelical Church, had arrived in Argentina with his family just before the First World War. Although his initial plan was to serve as a pastor in Buenos Aires for a short time, the family never left and settled permanently in the city. In addition to being a passionate researcher, she was an enthusiastic teacher, always willing to transmit her knowledge with patience and detail. Margarita was also a devoted mother, grandmother and accomplished musician. She began playing the violin at nine, loved Baroque music and performed with friends until her final days. To me, she was a dear friend. She passed away shortly after Christmas in 2022. She was 84 years old.
Three years ago, I invited Margarita to participate in an interview to celebrate the International Day of Women and Girls in Science. She carefully considered the proposal but humbly declined it. She thought her research and experience were not noteworthy enough to serve as an example. I disagree. I believe her story is an inspiring example of how passion and commitment can empower women in developing countries – often juggling childcare responsibilities and scarce research resources – to have a long-lasting impact on the scientific community. This article is a brief tribute to her passion and dedication to science.
Pioneering helminthology in Argentina
Margarita studied biological sciences at the University of Buenos Aires and graduated in 1963. She began her career under the guidance of Dr. Lothar Szidat at the Museum of Natural Sciences in Buenos Aires. Szidat, a pioneer in helminthology in both Europe and Argentina, introduced Margarita to the intricate world of parasitic worms and host ecology.
During her days as a student, she met Josué Núñez, a fellow prominent Argentine biologist, with whom she formed a family. While doing her PhD, Margarita married, had three children and supported her husband’s career. Margarita finished her PhD in 1973 and welcomed a fourth child soon afterward. Despite the challenges of raising a large family, her curiosity and dedication to science never wavered.
The family moved to Venezuela between 1976 and 1982, where she carried out her research at the Venezuelan Institute of Scientific Research. They next settled back in Buenos Aires where she was appointed Professor of Helminthology at the University of Buenos Aires. Margarita also taught at other universities in Argentina, Germany, Mexico and Uruguay, forged international collaborations and travelled for research stays on several occasions across Europe.
Margarita is celebrated as one of Argentina’s leading figures in helminthology and her research significantly advanced the understanding of helminths’ biology, ecology and taxonomy. These creatures include four major types of parasitic worms: roundworms (nematodes), thorny-headed worms (acanthocephalans), flukes (trematodes) and tapeworms (cestodes). These animals have a fascinating biology, with most species exhibiting complex life cycles. The larval stages can be found in one or more intermediate hosts, while the adult stage – in which the worm matures and sexually reproduces – infects a definitive host. Thus, these organisms must infect multiple host species in a specific order to mature, reproduce and complete one generation. Helminths infect wildlife and humans producing significant morbidity and mortality in vertebrate populations (in developing countries, they are the most common human infectious agents).
Studying helminths is laborious and involves several steps. First, specimens need to be collected from the hosts (this involves collecting potentially infected animals in the field). The parasites must be collected while still alive (i.e., shortly after euthanizing the host) and prepared for careful examination under the microscope. Expert knowledge is needed to differentiate helminths from other tissue debris and also to recognize different organs and structures allowing for taxonomic identification. Elucidating their complete life cycle adds complexity as it requires infecting the right host with the right parasitic stage (eggs, larvae or adults) at the right moment, and then going back to the morphological examination at each stage.
Margarita excelled at all this. She demonstrated remarkable endurance and good humor during exhausting specimen collection campaigns in the field. She worked tirelessly with precision and dedication, producing exquisite descriptions and images of hundreds of alien-looking helminths. Her resourcefulness stood out, as she often crafted her own instruments – something extremely valuable for scientists working with scarce research funding. Her tenacity led her to describe over 100 larval stages and experimentally elucidate the life cycles of more than 30 species of helminths from the Neotropical region. She discovered several new species, particularly within the groups of acanthocephalans and trematodes. Her accurate analysis also allowed her to solve numerous cases of cryptic species, that is, species with morphologically identical adults but distinct life cycles.
One of the most unique aspects of Margarita’s story is that much of her research took place in a home-based laboratory. With her husband’s support, she converted a hut in her garden into a fully equipped lab. There she kept everything she needed for her experiments, including books, a microscope, parasite preparations and live animals (e.g., snails, fishes and chickens) serving as helminths hosts. Though she taught and supervised students at the university, Margarita spent countless hours in her home-based lab, often at odd hours, painstakingly observing parasites across their developmental stages. After officially retiring in 2013 as a principal investigator at the university, Margarita remained highly active in her home-based lab. Her work during the post-retirement years led to the publication of some of her most significant contributions.
Recognition and impact
Margarita authored over 100 publications in international journals and left an indelible mark on her peers. She mentored various scientists who then consolidated research groups across Argentina. As a testament to her authority, the international helminthological community honored her repeatedly during her lifetime, with several species named in her honor (e.g., Neoechinorhynchus ostrowskiae sp., Travassiella margaritae sp.). Moreover, in 2018, the World Federation of Parasitologists awarded her with the Distinguished Achievement Award for her outstanding contribution to the field.
Margarita's research expanded scientific knowledge of helminths diversity, their ecological roles and evolutionary relationships and her legacy will certainly undoubtedly continue to inspire new generations of researchers. Beyond her scientific achievements, Margarita will be remembered for her humble, funny and passionate character. Those who had the joy of knowing her will forever treasure her vibrant spirit and unwavering dedication to both science and life.
