TABLE 1 .
Geographic origin and period of isolation of B. pertussis strains used in this study
| Continent | Country | No. of strains | Isolation period | Introduction of vaccination |
|---|---|---|---|---|
| Africa | Kenya | 17 | 1975 | 1980s |
| Senegal | 4 | 1990-1993 | 1980s | |
| Asia | China | 2 | 1957 | Early 1960s |
| Hong Kong | 5 | 2002-2006 | 1950s | |
| Japan | 17 | 1988-2007 | 1950s | |
| Taiwan | 23 | 1992-2007 | 1954 | |
| Australia | Australia | 37 | 1974-2007 | 1953 |
| Europe | Denmark | 9 | 1962-2007 | 1961 |
| Finland | 16 | 1953-2006 | 1952 | |
| France | 11 | 1993-2007 | 1959 | |
| Italy | 15 | 1994-1995 | 1995 | |
| Netherlands | 60 | 1949-2010 | 1953 | |
| Poland | 16 | 1963-2000 | 1960 | |
| Russia | 2 | 2001-2002 | 1956-1959 | |
| Sweden | 23 | 1956-2006 | 1953 | |
| United Kingdom | 20 | 1920-2008 | 1957 | |
| North America | Canada | 17 | 1994-2005 | 1943 |
| USA | 36 | 1935-2005 | 1940s | |
| South America | Argentina | 13 | 1969-2008 | 1970s |
| Total | 343 | 1920-2010 |