Temporal Trends in Bordetella pertussis Populations, Denmark, 1949–2010
Figure 2. . . Temporal trends in the frequency of multilocus variable-number tandem repeat analysis types (MTs) of Bordetella pertussis isolates collected in Denmark, 1949–2010. MTs represented in 1–3 isolates are compiled into 1 group denoted minor types. Years containing 1 or 2 isolates are combined with another year in the same time period, as indicated. The number of isolates analyzed each year/years is given above each column.