Health Education Research, Vol. 16, No. 4, 493-502,
August 2001
© 2001 Oxford University Press
SHORT COMMUNICATION |
Impact of health education on knowledge and prevention behavior for congenital toxoplasmosis: the experience in Pozna
, Poland
Professor Emeritus, University of Medical Sciences, Dabrowskiego Street 79, 60-529 Pozna
, Poland,
1 Institute of Social Medicine, University of Medical Sciences, 60-529 Pozna, Poland,
2 Institute of Microbiology and Infectious Diseases, University of Medical Sciences, 60-529 Pozna, Poland,
3 Provincial Sanitary-Epidemiological Station, 61-707 Pozna, Poland and
4 Epidemiology Branch, Division of Parasitic Diseases, NCID, Centers for Disease Control, Atlanta, GA 30324, USA
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Abstract |
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In 1991–1997 educational activities were undertaken in the Pozna
region of Poland to promote health education for the prevention of toxoplasmosis. The effect of education was measured in 2710 pregnant women by a questionnaire survey. Knowledge of toxoplasmosis and its prevention was almost doubled within 4 years. Similarly, the proportion of women having antenatal serological tests for toxoplasmosis significantly increased. In the examined population the knowledge of how Toxoplasma gondii is transmitted/acquired was better than the knowledge of individual risk factors for congenital toxoplasmosis. Correct hygienic behaviors in pregnancy were often practised by women who lacked good knowledge of toxoplasmosis. The experience from this study suggests the possible effectiveness of including prevention of toxoplasmosis into the whole package of preventing infectious diseases in pregnancy and into healthy lifestyle promotion. Health educational activities need to be realized by modern promotional technologies in addition to making available traditional written educational texts. There is a considerable role of medical services in promotion of a hygienic behavior in pregnant women preventing congenital toxoplasmosis in their offspring. Health education should be especially tailored to the population of pregnant women below the age of 21. |
Introduction |
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Toxoplasmosis is the most common parasitic infection in Europe (Zuber and Jacquier, 1995
). In Pozna Province, Poland, the toxoplasmosis seropositivity rate in a sample of 3658 pregnant women was 58.9% in 1991–1992 (Pawlowski et al., 1994); similar prevalence rates were recorded in Germany (Janitschke, 1992) and in Switzerland (Stuerchler et al., 1987). Most of the Toxoplasma gondii infections are asymptomatic. Symptomatic, occasionally fatal, cases of toxoplasmosis occur mainly in individuals with inadequate immune function such as fetuses (congenital toxoplasmosis), patients with HIV/AIDS and those undergoing immunosuppressive chemotherapy because of transplantation or neoplasm. Toxoplasmosis is a zoonotic protozoan infection with a natural cycle involving cats as a definitive host, and a variety of other mammals and birds as intermediate hosts. The infection can be acquired by humans through ingestion of T. gondii oocysts, shed in the feces of infected cats, or by ingestion of T. gondii cysts, present in the raw or inadequately cooked meat of many species of animals. Toxoplasmosis may be acquired congenitally by the developing fetus when a pregnant woman has her primary infection during pregnancy.
Despite multiple sources of T. gondii infection, the risk of exposure to toxoplasmosis can be reduced by improved personal hygiene and meat processing standards, as well as through effective environmental protection and health education. Health education is one of the widely accepted primary preventive measures in toxoplasmosis (Frenkel, 1981). An attempt was made to evaluate the potential of health education in reducing the exposure to congenital toxoplasmosis during a study initiated in Pozna, Poland starting in 1991 and carried out till 1999.
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Material and methods |
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Study design
Various educational activities were initiated in the mass media, secondary schools, and among professional medical personnel and pregnant women. The potential effect of these activities, especially the role of the mass media, a printed educational brochure and the impact of medical services, on promotion of health education were evaluated by questioning pregnant women. The degrees of knowledge of pregnant women on toxoplasmosis, its risk to fetuses, toxoplasmosis-related behavior and their interest in a healthy lifestyle were measured. These data were additionally related to seropositivity rates in the population of pregnant women, frequency of the individual serological examinations during pregnancy and an analysis of known cases of congenital toxoplasmosis in the Pozna
region.
Participants
All women hospitalized in four randomly selected obstetrics wards in the Pozna administrative region were involved in the study to achieve a representative sample of the population. Baseline data on levels of knowledge were obtained in 1995–1996 by questioning 1246 women twice, first at the initial visit to the Outpatient Clinic for pregnant women and later at home 1 week after birth of the child, and in 1997 by interviewing 2710 pregnant women once only at the time of hospitalization for delivery.
The groups of people involved in educational activities are specified below.
Educational activities
Intensive health educational activities in Pozna Province were carried out from 1991 to 1997 by personnel of the Provincial Sanitary-Epidemiological Station (Table I). In 1991, prevention of congenital toxoplasmosis was made an additional responsibility of the general programme of the Health Education Department of the Station. The educational activities were focused on secondary schools (toxoplasmosis was added to the continuing education curriculum for biology teachers) as well as the personnel of Outpatient Clinics for pregnant women (with refresher training of nurses and midwifes). A brief, 1-page `fact sheet' with basic information on the prevention of congenital toxoplasmosis was prepared and widely distributed among pregnant women attending Outpatient Clinics in 1991 and the during following years. The basic information was focused on avoiding eating raw or semi-raw meat (sausages, mince) and/or having contact with cat's faeces (directly or indirectly through contaminated soil) as well as testing for Toxoplasma antibodies before or during pregnancy. In 1996, a 15-page booklet on the prevention of infectious diseases in pregnancy was published. The booklet described ways of transmission, prevalence rates, basic diagnostic methods and preventive measures of toxoplasmosis, and cytomegalovirus infections (CMV), viral hepatitis B, rubella and HIV infections. As many as 10 000 copies were distributed to the Outpatient Clinics for pregnant women in the Pozna region (Slomko and Szczapa, 1997) and, subsequently, 300 000 copies were distributed throughout the country.
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Other educational activities included the organization of two conferences on congenital toxoplasmosis for medical doctors (Slomko et al., 1995
; Pawlowski and Szczapa, 1992) and an article on the subject published in a popular journal for obstetricians (Pawlowski, 1994). Some educational activities such as informative sessions and discussions were introduced into the programme of pregnant women clubs, which are voluntary educational groups organized at most of the Outpatient Clinics.
Measurement of knowledge and behavior of pregnant women
A standardized questionnaire was used throughout the study that collected basic data on the prospective mother (age, educational level, living conditions, occupation, present and past pregnancies, and medical care). It queried information on the participant's knowledge of Toxoplasma infection, its risk to the fetus, appropriate preventive hygienic behavior in pregnancy and the importance of practicing a healthy lifestyle. The questionnaires were administered by specially trained nurses or midwifes.
Individual answers to five questions concerning knowledge of toxoplasmosis were ranked from 1 to 6 according to their importance in prevention of the infection (e.g. avoiding eating raw meat, 6 points; washing hands after contact with a cat or soil, 3 points). The degree of knowledge was estimated by summing up the points for each question. Scores between 8 and 13 were arbitrarily rated as good; scores 7 or less were considered to be indicative of inadequate knowledge. Either eating raw meat during pregnancy or having direct contact with a cat's faeces was rated as an incorrect behavior. An active interest in a healthy lifestyle, such as looking for related information, reading, listening, exchanging views on health matters, practicing good diet and exercise, was evaluated simply by `yes' or `no'.
The data derived from the questionnaires were entered into a computer database and analyzed for statistical significance using SPSS (correlation level) and EpiInfo (P values) programmes.
Epidemiological data
In order to compare the epidemiological situation in congenital toxoplasmosis in the Pozna region in the years 1991–1992 and 1997, 1534 randomly selected women giving birth were examined (by M. P.) for the presence of IgG-specific Toxoplasma antibodies with a standardized direct agglutination (DA) technique (Pawlowski et al., 1994).
The proportion of pregnant women individually examined for Toxoplasma antibodies prophylactically was measured by questioning using an identical questionnaire as in the years 1991–1992.
The mothers of 29 newborns diagnosed with congenital toxoplasmosis by a large-scale screening programme (M. P.) in 1996–1999 were queried for behavior and practices which may be related to the risk of infection. The data were compared with the knowledge and behavior of the 2710 pregnant women questioned with the same protocol. The number of infected newborns was extrapolated from the number of women giving birth in each group (age, place of living, education, profession and number of pregnancies).
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Results |
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Knowledge of toxoplasmosis
In 1997, 1224 (45.3%) of 2710 women questioned had an `adequate' knowledge of T. gondii transmission and preventive measures (Tables II and III
). The levels of knowledge were better in women residing in an urban area (Ccor = 0.62), in women with secondary and/or higher education levels (Ccor = 0.44), and in women of the medical profession (Ccor = 0.36). No significant differences in knowledge levels were noted in women engaged in `high-risk' activities (e.g. professionally involved in the preparation of raw meat food) nor in primagravida women compared with those in their third or more pregnancies (Table III).
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Knowledge levels increased during the course of observation from 24.3% in 1991–1992 (Pawlowski et al., 1994
) to 45.3% in 1997 (Table II
). No differences were noted between data collected in 1995–1996 and 1997 (Table II).
A striking increase in knowledge from 45.5 to 80.3% was observed when the same women were questioned in 1996–1997 at early pregnancy and 1 week after giving birth (Table II).
Knowledge of risk of congenital toxoplasmosis
In 1997, specific knowledge of the potentially harmful effect of toxoplasmosis on the developing fetus (28.9%) was significantly less than general knowledge of transmission and source of infection in toxoplasmosis (45.3%) (Table III). Knowledge of the risk of congenital toxoplasmosis was higher in the urban sample (Ccor = 0.31) and in more educated women (Ccor = 0.76). Of special note was the finding that only 77.4% of 146 pregnant women in the medical profession were aware of the risk of congenital toxoplasmosis, although 96.2% of them had heard of toxoplasmosis.
Toxoplasmosis-related behavior in pregnancy
Hygienic behavior considered conducive to prevention of toxoplasmosis was reported in 1496 (55.2%) of 2710 women questioned (Table IV). This percentage exceeded the proportions who reported general knowledge of toxoplasmosis transmission (45.3%) and specific knowledge of the risk of congenital toxoplasmosis (28.9%) because some of the women apparently lacking knowledge of toxoplasmosis and congenital toxoplasma risk nevertheless practised correct preventive behavior (78.2%) (Table IV).
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Correct preventive behavior was not correlated statistically with age, place of living, educational level and profession. However, some positive or negative statistical trends (P values) can be noted (Table III
) in women living in urban areas and small villages, having secondary and higher education, being medical professionals, and being pregnant on a second or more occasions.
Sources of information on toxoplasmosis
Information on toxoplasmosis was reportedly obtained from multiple sources. In 1997, more than 60% of 2710 women questioned had heard about toxoplasmosis through television or had read about it in women's magazines. Radio, daily newspapers and health services providers were the reported sources for fewer than 40% of the responders. Books and other people were a less frequent (below 30%) source of information.
The effect of written educational materials was below our expectations. In 1997, the brochure How to Avoid Infectious Diseases in Pregnancy (Slomko and Szczapa, 1997) had been read by only 352 pregnant women, i.e. 24% of all pregnant women consulted in national service Outpatient Clinics, where the brochure should have been accessible (Table II). The effects of having read specially prepared written educational material on the level of knowledge about toxoplasmosis and changing the toxoplasmosis-related behaviors were statistically insignificant (P = 0.95 and P = 0.8, respectively).
Role of medical services in health education
In 1997, approximately 98% of 2710 pregnant women involved in the study had consulted an obstetrician and 57.7% of them had more than 10 consultations during pregnancy (mostly the women pregnant the first time). National health services only were used for consultations by 36.4% of pregnant women, private doctor consultations only by 45.0% and both of these sources by 18.6%. Of note was a considerable shift in these proportions during the period of the study in favor of the private medical sector; in 1991–1992 the respective figures were 63.2, 26.4 and 9.2%.
In the special survey carried out in 1995–1996 there was evidence of an improved knowledge of T. gondii infections in pregnant women attending the national Outpatient Clinics from 45.5% having `good knowledge' at the beginning of pregnancy to 80.3% shortly after delivery (Table II).
The impact of the private medical sector on health education appears to be comparable to government services as the proportions of women practicing a correct behavior did not differ significantly between those women who attended national service clinics (73.4%) and private consultations (79.8%) (Table II).
There are, however, significant differences between possessing good knowledge on toxoplasmosis, good knowledge of potential risk of congenital toxoplasmosis and practicing a correct behavior in pregnancy among those women who attended the clinic more than 10 times during pregnancy (53.2, 42.8 and 96.9%, respectively) and those who attended less than six times (3.7, 3.3 and 14.6%) (Ccor = 0.73). These data, however, may be influenced by other confounding factor(s) responsible for the frequency of the visits at medical centers and increased interest in health matters during pregnancy.
Selected epidemiological data
In the years 1997–1999, among 1534 women giving birth, 675 (44.0%) had specific IgG antibodies against T. gondii in the DA test.
The proportion of pregnant women reporting having had an antenatal serological Toxoplasma test rose significantly from 2.7 to 4.6% between the years 1991–1992 and 1997 (Table II). The increase was significantly higher among pregnant women living in urban areas, those having secondary education, those from medical professions and those who had been pregnant three or more times (Table III).
Among 23 mother of newborns diagnosed with congenital toxoplasmosis who responded to the questionnaire, 21 (91%) had a behavior accepted as incorrect (eating raw or semi-raw meat, having close contact with cat's faeces, especially that of kitten) (Table III). Higher rates of congenital infections were found among women less than 20 years of age (P = 0.014) than in older women. The increased numbers of congenital toxoplasmosis in the offspring of the women with higher education (P = 0.15), in the medical profession (P = 0.34) and in the first pregnancy (P = 0.06) were not statistically significant.
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Discussion |
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Role of health education and limitations in its measurement
The basic principles of prevention of congenital toxoplasmosis were defined with the elucidation of the modes of transmission of T. gondii (Frenkel, 1981
). Health education is generally accepted as an important, inexpensive, primary preventive measure (Petersen, 1992). Even in countries where priority is given to antenatal screening, as in France, health education has been accepted as an important secondary effect of the screening programme (Thulliez, 1992). In the UK, health education was promoted, but not a screening programme (Henderson et al., 1984). Although a general opinion exists that health education alone has limited efficacy for prevention of toxoplasmosis, there is wide agreement that it should be a standard element of the basic obstetric care and one of the basic responsibilities of the public health services (Carter et al., 1989).
Evaluation of the effectiveness of health education was sporadic because of difficulties in measuring its impact (Do et al., 1995). The major problem is a weak time relation between the performance of health educational activities and the acquisition of infections, characterized by frequent exposures (some starting already in the childhood), long-lasting seropositivity, mostly asymptomatic infections and low rates of congenital toxoplasmosis in populations. Moreover, the effects of health educational activities cannot be clearly separated from the other on-going social and economic developments which may have a preventive impact, such as improved food technology and general improvements in personal hygiene in populations (Foulon et al., 1994). Health education itself is also a long-term process, which can hardly be evaluated in terms of a few years of observation. Considering all these sources of potential bias, the final conclusion from this study are drawn with caution.
The effect of health education in the Pozna study
The most objective way to evaluate the impact of health education is by comparing the annual numbers of cases of congenital toxoplasmosis for several years before and after the intervention; such data are not available from Poland. An analysis of 29 cases of congenital toxoplasmosis recently detected in newborns in the Pozna region demonstrated that the mothers of infected neonates were frequently 20 years old or less (P = 0.02); the potential significance for prevention of higher education, profession and number of pregnancies is statistically less evident, probably because the number of the cases is still low. The study confirmed that the majority of the mothers (26 of 29) of infected newborns practiced eating raw meat or had a close contact with young cats. The need for better health education in youngsters, in whom both Toxoplasma seropositivity and early pregnancy rates are relatively high, is well substantiated.
The rate of seropositivity in pregnant women in the Pozna region has dropped from 58.9% in 1991–1992 to 44.0% in 1997. This reflects the general trend in Europe and improved education is only one of the responsible factors. Reduction of the seropositivity rate increases the proportion of seronegative women potentially susceptible to Toxoplasma infection in pregnancy and may not influence the rate of congenital toxoplasmosis in the population. The proportion of pregnant women receiving toxoplasma serological tests has increased from 2.7% in 1991–1992 to 4.6% in 1997 (Table I); this positive trend may help to identify T. gondii infections antenatally and reduce the pathogenic effects of congenital toxoplasmosis. However, it has been observed that most of the serological tests have been done in women attending the outpatients clinic frequently (more than six times), possibly because of other medical problems related to pregnancy. Women from the medical profession, living in an urban agglomeration and having a higher education had serological tests done more frequently. This appears to reflect the improved skills of medical doctors, higher levels of knowledge among pregnant women and also the better accessibility of the serological tests in towns.
The effect of an active health education campaign in Pozna seems to be considerable when looking at the increased knowledge about toxoplasmosis among pregnant women over 5 years time from 24.3 to 45.3% (Table II). However, it was less evident considering knowledge about the specific potential risk of toxoplasma infection to the fetus, which could strongly motivate a change in behavior—the final aim of education (Table IV). The results of the interview behavior disclosed an interesting observation that even among those women who have a good knowledge of toxoplasmosis or its risk to the developing fetus, one-third still practice risky, inadequate behavior. On the other hand among those who do not have an adequate knowledge of toxoplasmosis, as assessed by our survey, almost one-half follow a toxoplasma-related correct behavior (Table IV). An active interest in a healthy lifestyle, reported by 29% of the population studied, is strongly correlated with toxoplasma-related correct behaviors.
Specific versus general health education
There are few publications which propose that health education concerning congenital toxoplasmosis should be a part of the general campaigns for a healthy lifestyle in pregnancy (WHO, 1984,1987; Conyn-van Spaedonck and van Knapen, 1992). In the Pozna study, recommended toxoplasma preventive measures have been combined with the prophylactic measures for other congenitally transmitted infections such as HIV, viral hepatitis, rubella and CMV (Slomko and Szczapa, 1997).
Interest in a healthy lifestyle was well correlated with toxoplasma-related correct behavior (Table IV) (Ccor = 0.41 ). Therefore, the results of our study suggest that health education in pregnancy should ideally be directed at all the aspects of a healthy lifestyle, and promote an interest and motivation to take optimal care of the prospective mother and her fetus. As several infectious diseases have common preventive measures (e.g. washing hands, food safety), there is a good reason to include specific toxoplasma health education in the whole package of congenital infectious diseases prevention rather than deliver it separately (WHO, 1987; Slomko and Szczapa, 1997).
Optimal methods for delivery of health education
Considering seroepidemiological data (only 56% of pregnant women susceptible for primary infection in pregnancy) and data related to healthy behavior in the population (55.2%), one may expect that less than 25% of all pregnant women need a specific health education on prevention of congenital toxoplasmosis. However, in the absence of a serological screening programme for the presence of specific Toxoplasma antibodies, this portion of pregnant women cannot be defined and health education has to be addressed to all pregnant women. Moreover, the preventive education in toxoplasmosis has to be addressed especially to pregnant women at the age of 20 and below because they had the lowest level of knowledge and the highest frequency of congenital toxoplasmosis.
The delivery of health education is still mainly based on the preparation and distribution of written educational material. Critical evaluation of the standards of educational material in Europe showed them to be unsatisfactory (Do et al., 1995). Distribution of the educational booklet was less widespread than expected. Although the brochure on prevention of congenitally transmitted infectious diseases has clear, practical messages formulated in a simple language, the survey indicated that it has rather weak correlation between the knowledge derived from the brochure and level of knowledge on toxoplasmosis (Ccor = 0.23) or correct toxoplasma-related behavior (Ccor = 0.14). The opinion seems to be true that the effect of written educational material depends much on the general intellectual level of the population and individual motivation to learn more on healthy lifestyles, especially during pregnancy. The mass media, using visual and personal contacts, seems to be more effective in delivering health education to the general population, and this was confirmed by questioning women during our study.
The educational role of medical personnel, especially those practicing in Outpatient Clinics for pregnant women, was confirmed to be the most effective—almost doubling the rate of knowledge on toxoplasmosis when measured at early pregnancy and shortly after delivery. However, there are two major factors which may have a negative effect on educational programmes in medical institutions: (1) medical staff having no time or interest for promoting health education and (2) a lack of high quality health educational materials developed using modern promotional technologies. A practical alternative for the effective delivery of health educational material would be waiting rooms in Outpatient Clinics (including private ones), clubs for pregnant women, ladies weekly magazines and television. It is time to introduce modern promotional technologies in health educational activities such as audio and/or video cassettes, discussion groups, and interactive computerized programmes, games and competition that can be used in addition to the traditional health education delivery systems based mainly on written messages.
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Acknowledgments |
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The study were encouraged by European Research Network on Congenital Toxoplasmosis and supported from Polish–American scientific co-operation grant Maria Curie Sklodowska Joint Fund II MZ/NIH 96–291.
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References |
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TopAbstractIntroductionMaterial and methodsResultsDiscussionReferences |
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Received on March 14, 2000; accepted on November 14, 2000
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