Childhood Virus Newly Identified as an Important Contributor to Severe Anemia in the Tropics

New research suggests a common childhood virus is a previously unknown contributor to childhood anemia. An estimated one million children die of anemia each year, mostly in the developing world. The study appears in the July 15 issue of the Journal of Infectious Diseases, now available online.

Parvovirus B19 infects more than 50 percent of the world's population during childhood.  Acute infection causes a temporary halt in red blood cell production lasting 3-7 days.  While this lack of red blood cell production usually causes no problem in healthy adults, it can be much more serious for children in regions where malaria, sickle cell disease, and other hemolytic disorders are rampant and anemia is already very common.

Yvonne Cossart, MBBS, DCP, and colleagues at the University of Sydney and the Papua New Guinea Institute of Medical Research collected and compared blood samples from anemic children in Papua New Guinea 6 months to 5 years old to those of equivalent controls.  They tested the samples for B19 antibody and B19 DNA and found that "acute B19 infection showed the strongest association with severe anemia." 

Malaria infection was also more frequent in children with anemia. The study ultimately showed "the association found between acute B19 infection and severe anemia is comparable to that found with malaria, a leading cause of anemia in endemic areas."

"The decrease in hemoglobin level induced, when superimposed on a pre-existing moderate anemia, may become  a proverbial 'last straw' that pushes the already-anemic child [into] severe anemia," according to the study.

The authors call for strengthening of efforts to develop an effective vaccine against parvovirus B19 to prevent severe anemia among young children.

Editorialist Geoffrey Pasvol, MA, MBChB, DPhil, from the Wellcome Centre for Clinical Tropical Medicine at Imperial College in London, says, "These findings highlight the importance of this hitherto unseen enemy as a leading contributor to anemia in the tropics."

He further concludes, "As these authors rightly indicate, development of a B19 vaccine may well be a highly effective public health intervention to reduce the severity of anemia in these regions."

Source: Infectious Diseases Society of America (IDSA)