Immunity against measles in populations of women and infants in Poland.

During the 1997-1998 measles epidemic in Poland a high attack rate occurred in infants up to 1 year of age (24.6/100,000 in comparison with 5.5/100,000 in total population). Routine vaccination against measles for infants aged 13-15 months was introduced in Poland in 1975, and a second dose added in 1991. The recommended age for measles vaccination was based on information gathered in years when most mothers had a natural measles. Nowadays, many mothers have received measles vaccine. Early loss of passively acquired measles antibody may occur in infants of women who received measles vaccine, because measles vaccine induces lower antibody titres than does natural infection. Therefore, measles-specific antibody titres were determined among vaccinated and unvaccinated women as well as among infants, whose mothers were born after 1976 and likely were vaccinated (Group 1), and those, whose mothers were born before 1969 and likely have had a natural measles (Group 2). All women that were born in prevaccination era had significantly higher geometric mean titre (GMT) of measles antibody than those who were vaccinated (P<0.001). Also infants from Group 2 at every age had higher GMT of measles antibody than those of Group 1. The antibody decay was significantly faster among infants whose mothers acquired immunity by measles vaccination. Because nowadays the majority of women in childbearing age are vaccinated against measles, earlier vaccination in the infants should be considered.

Measles vaccine efficacy during an epidemic in 1998 in the highly vaccinated population of Poland.

A measles epidemic with 2255 reported cases occurred in Poland between November 1997 and July 1998, despite high vaccination coverage since the 1980s. Cases occurred at all ages less than 30 years but showed two distinct peaks: young, unvaccinated children born in 1996-1997 and once vaccinated young adults born 1976-1982. The 60% of cases were among persons aged 15 years or more. A cohort study was used to investigate measles vaccine efficacy. The efficacy of a single dose of vaccine exceeded 90% and the efficacy of two doses exceeded 99% in all age-groups. These results demonstrate both the high efficacy of the monovalent measles vaccines used in Poland and the benefit of a second dose of vaccine.

[Immunity of children aged 6-8 against pertussis, tetanus and diphtheria]. / Stan uodpornienia dzieci w wieku 6-8 lat przeciw krztuscowi, tezcowi i blonicy.

Vaccination against pertussis has been performed since 1960. Whole cell pertussis vaccine produced by Plant of Sera and Vaccines Biomed S.A. in Kraków, has been used. After vaccination has been introduced, epidemiological situation of pertussis in Poland improved, but in 90's the decrease of immunity was observed. The aim of this work was to determine pertussis immunity of children after several years from the last dose of pertussis vaccine. For comparison purposes immunity against tetanus and diphtheria was tested. Protective antibody levels were detected in 70%, 58%, and 45% children aged 6, 7, and 8, respectively. It shows that decrease of immunity may cause increasing number of pertussis in children above 5. Taking into consideration our results, it seems necessary to introduce additional dose of pertussis vaccine among children aged 5 years. The level of tetanus and diphtheria antibodies was high in all tested groups.

[Eradication of leprosy and public health. Vaccination and multidrug therapy]. / Perspektywy eliminacji tradu w swiecie. Szczepienia ochronne a leczenie etiotropowe.

Leprosy is a disease, which still affects large populations in the developing countries particularly in Africa, Asia and Latin America. For the last 15 years significant advances have been made towards leprosy elimination. The most effective strategy for leprosy control is an early identification of cases and an effective treatment with multidrug therapy (MDT). The vaccination against leprosy plays only an additional role. There are two possible approaches to develop vaccine against leprosy. One is to produce a vaccine based on organisms related to M. leprae, such as: BCG, ICRC bacillus, Mycobacterium w, Mycobacterium vaccae, Mycobacterium habana. However, these organisms related to M. leprae are not very promising in experimental animal studies. In 1970s a new vaccine was prepared based on killed M. leprae. This vaccine, tested alone and together with BCG revealed little impact on increasing vaccine efficacy. The success in cloning and expressing the M. leprae genome in E. coli created the possibility of moving towards a second generation vaccine using peptide antigens. Up till now only MDT has essential impact on decline of global leprosy prevalence. Out of 122 endemic countries in 1985, 107 countries have reached elimination of leprosy at country level. At the end of 2000 leprosy was a public health problem only in 15 countries (prevalence rate > 1/10.000). Currently leprosy remains a problem mainly in 6 major endemic countries. Among these, India alone accounts for 64% of prevalence and 78% of detection worldwide.