Background and Aims To evaluate the National Immunisation Programme (NIP) a population-based cross-sectional seroepidemiological study was performed in the Netherlands. indicated a continuous decrease in antibodies in both serosurveys, but geometric imply antibodies remained well above 0.01 IU/ml in all age groups. Conclusions The NIP provides long-term safety against diphtheria, although antibody levels decrease after vaccination. As a result of natural waning immunity, a substantial proportion of individuals created before intro of diphtheria vaccination in the NIP lack adequate levels of diphtheria antibodies. Susceptibility due to lack of vaccination is definitely highest among purely orthodox Protestants. The potential risk of spread of diphtheria within the geographically clustered orthodox Protestant community after intro in the Netherlands Rabbit Polyclonal to BAGE4. has not disappeared, despite national long-term high vaccination protection. Introduction Despite the success of routine vaccination, diphtheria is still a serious child health problem with 5, 000 diphtheria instances globally in 2012, occurring in particular in South-East Asia . The major diphtheria outbreak in the Newly Independent States of the former Soviet Union during the 1990s, with > 150,000 instances indicated that diphtheria can reemerge in vulnerable populations [2C4]. In the Netherlands, diphtheria was endemic before intro of diphtheria vaccination in 1957. The last diphtheria epidemic occurred during World War II with Laropiprant > 190,000 instances reported between 1940 and 1945. Since 1960, diphtheria has become a rare disease in the Netherlands . However, the recent diphtheria case in Spain shows the importance of vaccination against diphtheria, actually in non-endemic countries . In addition, an important issue growing in literature is the shortage of diphtheria antitoxin (DAT) [6C9]. This immunoglobulin preparation is needed for the treatment of diphtheria and most Laropiprant effective when given as early as possible [6C8]. The possible lack of appropriate DAT supply emphasizes the need of keeping high vaccination protection . Vaccination against diphtheria was launched in the Dutch National Immunization System (NIP) in 1957 using a combination vaccine including the diphtheria, tetanus and whole-cell pertussis (DTwP) vaccine. From 1962 onwards, babies received a combined vaccine including diphtheria, tetanus, whole-cell pertussis and inactivated polio vaccine (DTwP-IPV) at three, four, and five weeks of age, followed by a booster vaccination at 11 weeks of age. Booster vaccinations at four and nine years of age with DT-IPV were added to the NIP Laropiprant in 1965. From 1999 onwards, the 1st three infant doses were given at two, three and four weeks of age. The routine with six diphtheria vaccinations is still in use, however, the combination vaccines used in the NIP in the Netherlands have changed several times in composition and of manufacturer . In 2003 (Hib) vaccine was added to the DTwP-IPV vaccine for babies (DTwP-IPV/Hib) and in 2005 the infant whole-cell pertussis vaccine Laropiprant was replaced by an acellular pertussis vaccine (DTaP-IPV/Hib) . In 2006 a seven-valent pneumococcal vaccine conjugated to a non-toxic, fully immunogenic mutant of diphtheria toxin (CRM197) was added to the NIP at two, three, four, and 11 weeks of age for those children created in or after April 2006. In addition, in July/August 2006, acellular pertussis vaccine was added to the booster combination vaccine for 4-year-olds (DTaP-IPV). Vaccination protection for diphtheria has been continually high (> 90%) for at least the last 35 years Laropiprant . However, in the Netherlands you will find areas with low vaccination protection (LVC). In these areas reside a relatively high proportion of socio-geographically clustered orthodox Protestant individuals who decrease vaccination based on religious grounds. Vaccination protection among orthodox Protestant individuals was overall about 60% (measured in 2006/2007 and 2008) . We present results of a national seroepidemiological study performed in 2006/2007 assessing diphtheria antibodies in.