Epidemiology, Parvovirus B19, surveillance, outbreak investigation
Purpose:
Parvovirus B19 is a common cause of childhood infection with fever/rash symptoms. The clinical presentation
of parvovirus B19 can be mistaken for rubella or measles. This usually mild illness can cause complications in
certain groups, including pregnant women. As Europe is seeking to eliminate measles, an understanding of the epidemiology of parvovirus B19 in Ireland is necessary.
Methods:
Acute infection is diagnosed by laboratory detection of parvovirus B19-specific immunoglobulin M (IgM). Data
were obtained from the National Virus Reference Laboratory regarding all samples tested for parvovirus B19
between January 2009 and December 2018. Data were analysed by the Health Protection Surveillance Centre
to describe the epidemiology of laboratory-confirmed parvovirus B19 by patient demographics, seasonal
variation, and geographical location.
Results:
Over the ten year time period, 4.3% (1,747/40,476) of parvovirus B19 IgM tests yielded a positive result.
Females were tested more frequently due to the risks associated with infection during pregnancy with 3.9% testing positive (1,334/34,347) compared to 6.7% (391/5,878) in males. The median age of females with laboratory-confirmed parvovirus was 31.9 years (range:0-84) compared to 10 years of age (range:0-85) for males.
Parvovirus B19 infection is seasonal with increases in infection rates in late spring and early summer. There is a
cyclical increase in the annual incidence every 3-4 years with peaks observed in 2012/2013 and 2017/2018.
Implications:
An understanding of the epidemiology of Parvovirus B19 in Ireland may facilitate appropriate case management and public health actions in the context of an outbreak where measles or rubella is suspected.