Parvovirus B19 infection in five European countries: seroepidemiology, force of infection and maternal risk of infection

Abstract

We conducted a seroprevalence survey in Belgium, Finland, England & Wales, Italy and Poland on 13 449 serum samples broadly representative in terms of geography and age. Samples were tested for the presence of immunoglobulin G antibody using an enzyme immunoassay. The age-specific risk of infection was estimated using parametric and non-parametric statistical modelling. The age-specific risk in all five countries was highest in children aged 7-9 years and lower in adults. The average proportion of women of child-bearing age susceptible to parvovirus B19 infection and the risk of a pregnant women acquiring B19 infection during pregnancy was estimated to be 26% and 0.61% in Belgium, 38% and 0.69% in England & Wales, 43.5% and 1.24% in Finland, 39.9% and 0.92% in Italy and 36.8% and 1.58% in Poland, respectively. Our study indicates substantial epidemiological differences in Europe regarding parvovirus B19 infection.

Fig. 1

Histograms of log parvovirus B19 antibody reaction level distribution of national serum banks in five countries. Left and right arrows indicate negative and positive cut-offs, respectively, as indicated by the manufacturer.

Fig. 2

Panels (a–e) show different estimates of parvovirus B19 seroprevalence profiles in Belgium, England & Wales, Finland, Italy and Poland, respectively. The open symbols (○) indicate point estimates for each age group, the thick line indicates the local quadratic model and the thin line indicates the piece-wise constant model. Panels (f–j) show the force-of-infection (FOI) estimates corresponding to the seroprevalence profiles in panels (a–e), respectively. The thick line indicates the local quadratic model; the dotted line represents 95% confidence intervals of the local quadratic model, and the thin line the piecewise constant model.

Fig. 3

(a) Comparison of age-specific parvovirus B19 seroprevalence profiles in Belgium, England & Wales, Finland, Italy and Poland estimated using the local quadratic model. (b) Comparison of age-specific parvovirus B19 force-of-infection (FOI) estimates from the local quadratic model in Belgium, England & Wales, Finland, Italy and Poland.

Fig. 4

Distribution of live births by age of mother in 1997 (shown by histograms, y-axis on the left) according to Eurostat, and distribution by age of annual estimated number of B19 infections occurring during pregnancy based on the local quadratic model of seroprevalence and force of infection (––––, y-axis on the right).

Fig. 5

Incidence of notified B19 infections in (a) England & Wales, (b) Finland. Arrows indicate timing of sera collection.