Albert Kapikian, center, works with colleagues Stephen Feinstone, left, and Robert Purcell. Dr. Kapikian was perhaps best known for his study of the rotavirus, which the World Health Organization describes as a leading cause of severe diarrheal disease and dehydration in infants and young children worldwide. (National Institute of Allergy and Infectious Diseases )

Albert Z. Kapikian, a virologist who helped lead important advances in the understanding of gastrointestinal illnesses that strike populations around the world — particularly children — died Feb. 24 at a rehabilitation center in Potomac, Md. He was 83.

The cause was congestive heart failure, said his wife, Catherine Kapikian.

Dr. Kapikian was a prominent researcher at the National Institute of Allergy and Infectious Diseases, a division of the National Institutes of Health in Bethesda, Md., and for more than four decades served as chief of the epidemiology section in the laboratory of infectious diseases.

He had joined NIH in 1957 as an officer of the U.S. Public Health Service and dedicated nearly his entire career to the study of viruses that can lead to an upset stomach in mild cases — and to death in severe ones.

In 1972, Dr. Kapikian used cutting-edge electron microscope technology to identify the Norwalk virus, an agent named for the town in Ohio where in 1968 it sickened more than 100 elementary school students and their teachers.

The Norwalk virus is considered the first identified noro­virus. Common and highly contagious, the norovirus is particularly dangerous in crowded environments such as day-care centers, college dormitories, military bases and cruise ships, said Stephen J. Chanock, an NIH infectious disease expert. Symptoms can include stomach discomfort, nausea, diarrhea and vomiting.

The year after his norovirus breakthrough, Dr. Kapikian and several colleagues were credited with identifying the virus that causes hepatitis A, a form of liver disease.

He was perhaps best known for his study of the rotavirus, which the World Health Organization describes as a leading cause of severe diarrheal disease and dehydration in infants and young children worldwide.

“It’s a very egalitarian virus,” Dr. Kapikian once told The Washington Post. “It infects children equally in developed countries as well as developing countries. Sanitary conditions don’t seem to matter.”

Limited medical care in poor countries, however, makes the rotavirus particularly threatening in those areas. It is estimated to cause 400,000 deaths or more per year.

Dr. Kapikian led the team of researchers that created and patented the first rotavirus vaccine to be licensed in the United States, according to NIH. To create the vaccine, Dr. Kapikian combined a monkey rotavirus with elements from several strains of human rotavirus.

The vaccine was approved by the Food and Drug Administration in 1998 but later was withdrawn because of an apparent association with rare cases of bowel obstruction. Dr. Kapikian continued pursuing research on rotavirus vaccines, and today two such vaccines are available.

“Al Kapikian was a giant in the field of virology,” Anthony S. Fauci, the NIAID director, said in a statement released on Dr. Kapikian’s death. “His seminal basic and clinical research contributions to the study of viruses and to vaccine development have had an enormous global impact.”

Albert Zaven Kapikian was born May 9, 1930, in the Bronx to Armenian immigrants. He considered joining a seminary before choosing to pursue a career in the medical sciences.

In 1952, he received a bachelor’s degree in history from New York’s Queens College, where he was a pitcher on the baseball team. Four years later, he received a medical degree from Cornell University.

Dr. Kapikian was in the Public Health Service until retiring at the rank of captain. He traveled worldwide for his medical work, his wife said, and remained associated with NIH as a consultant after his retirement in 2012. In addition to his work on the norovirus and the rotavirus, he did extensive research on the common cold.

His honors included the Sabin Vaccine Institute’s Albert B. Sabin Gold Medal, an honor named for the renowned polio researcher.

Dr. Kapikian was a Rockville, Md., resident. Survivors include his wife of 54 years, Catherine Andrews Kapikian of Rockville; three sons, Albert K. Kapikian and Thomas F. Kapikian, both of Silver Spring, Md., and Gregory B. Kapikian of Annapolis; a brother; and two grandsons.