A multicenter survey on toxoplasmosis knowledge among pregnant women in Poland (the TOWER study)

Toxoplasma gondii is an obligate intracellular protozoan parasite transmitted to humans through ingestion of food containing infectious oocysts that had been contaminated by feline feces (the definitive host), or ingestion of tissue cysts in undercooked meat of intermediate hosts, e.g. pork or lamb [1‐3]. The seroprevalence of T. gondii ranges widely in different areas of the world and different populations, from ≤10% to almost 100% [4, 5]. Although toxoplasmosis is typically benign and asymptomatic, it induces major complications in immunocompromised individuals and during pregnancy, where it can lead to miscarriage and congenital disease [6]. Congenital toxoplasmosis is a substantial burden for public health worldwide [7]. A previous report showed that about 41% and 5% of Polish pregnant women had specific IgG and IgM antibodies, respectively, and estimated that 1.5/1000 neonates were infected in utero [8].

Since there is no vaccine against T. gondii, prevention of maternal primary infection constitutes the major tool for avoiding congenital T. gondii infections and their complications. The preventive measures mostly depend on the women’s knowledge about toxoplasmosis, its transmission, and origin. Previous studies have shown different levels of pregnant women’s knowledge regarding the risk and consequences of toxoplasmosis infection during pregnancy. It remains controversial, however, if improved knowledge and access to reliable information about sources of infection are suitable to consequently change women’s behavior during pregnancy [9, 10]. Nevertheless, the aim of the study was to assess the toxoplasmosis knowledge of pregnant women in Poland.

The study was approved by the Institutional Review Board of the Polish Society of Disaster Medicine (approval No. 14.09.2016.IRB) and by the administrations of the healthcare institutions participating in the study. All data were anonymously collected and safely stored.

This cross-sectional, multicenter study was conducted between October 2016 and January 2017 in third-level hospitals in 3 Polish cities: Wroclaw, Warsaw, and Poznan. Pregnant women aged above 16 years who had a regular antenatal clinic visit in an outpatient clinic were asked to participate in the study. Once a patient agreed, written consent was obtained and the patient was interviewed in accordance with the pre-defined questionnaire by 2 of the researchers.

The total of 500 pregnant women were asked to participate in the survey. Of those, 465 agreed, which resulted in the participation rate of 93%. The demographic data of all the 465 subjects are shown in Table 1.

The education level of the study participants varied - 53 (11.4%) did not graduate from middle school, 111 (23.9%) graduated from middle school, 249 (53.5%) graduated from secondary school and 52 (11.2%) had university degree. Near half of the study participants - 231 (49.7%) reside in urban area and 234 (50.3%) in rural area. Number of pregnancies of study participants varied – 1 pregnancy was reported in 126 study participants (27.1%), 2 in 218 (46.9%) and 3 and more in 121 (26.0%).

Overall, 439 (94.4%) of the 465 included pregnant women were aware of the existence of toxoplasmosis. Among the most common sources providing information about toxoplasmosis, the following were reported: medical doctors (76.1%), the Internet (45.6%), television (41.3%), books (12.0%), and mother, family, or friends (1.9%).

According to 77.4% of the pregnant women, toxoplasmosis was a zoonotic disease, 41.7% believed that it was a parasitic disease, 8.6% were convinced that toxoplasmosis was transmitted through poor hand hygiene, 4% maintained that toxoplasmosis was a childhood illness, and 0.4% stated that it was a congenital disease.

The total of 84.3% of the surveyed did not know toxoplasmosis symptoms, and 12.0% stated that they did not present any symptoms of the disease. The pregnant women reported that the symptoms of toxoplasmosis included enlarged lymph nodes (3.4%), diarrhea (1.3%), and constipation (0.4%).

Among the preventative measures against toxoplasmosis, the respondents most frequently enumerated: avoiding contact with cats (83.9%), personal hygiene (46.0%), avoiding consumption of raw meat (45.8%), avoiding sandy beaches (4.9%), and avoiding contact with previously infected patients (0.4%).

In general, 83.2% of the participants believed that toxoplasmosis might be dangerous during pregnancy and according to 49.9% infection with the parasite could cause premature labor or miscarriage. When asked whether toxoplasmosis was a cause of any developmental defects in children (epilepsy, hypopigmentation, cataract, hydrocephalus, or heart defects), the vast majority of respondents (84.7%) reported no knowledge; 13.1% indicated heart defects as a potential consequence of toxoplasmosis, 11.4% pointed at hydrocephalus, 3.9% at epilepsy, and 1.3% at smallpox.

In the studied group, 83% did not know which trimester of pregnancy was associated with the greatest fetal risk related to the disease, whereas 17% indicated the first trimester.

Out of all the participants, 93.3% admitted that more emphasis should be put on health education related to toxoplasmosis prevention, 100% said that physicians should pay more attention to women at risk; 60.3% believed that the issue should be addressed in childbirth classes; 17.2% maintained that it should also be discussed by nutritionists.

To identify potential associations between high knowledge of T. gondii and socio-demographic characteristics, multivariate logistic regression analysis was conducted (Table 2). Younger age (OR, 2.74; 95% CI, 1.67–4.49; p <  0.001), city residence (OR, 13.45; 95% CI, 3.12–57.89; p <  0.003), and higher education level (OR, 6.81; 95% CI, 3.69–12.59; p <  0.001) turned out significantly associated with better knowledge of toxoplasmosis, and the number of children (OR, 0.32; 95% CI, 0.22–0.48; p <  0.001) – with higher knowledge of the symptoms.

The main finding of the current study was a high (94.4%) basic knowledge on toxoplasmosis among the studied pregnant women in Poland. This correlates with the recent results that pregnant women in Geneva, Switzerland had a high (87%) knowledge about toxoplasmosis [11], and about 75.3% of Dutch women had been exposed to information concerning toxoplasmosis [12]. These outcomes contrast with previous worldwide findings reporting a generally low level of knowledge about toxoplasmosis, risk factors, prevention, and consequences of the disease among pregnant women [13]. Ogunmodede et al. reported that less than half of pregnant women in the USA had heard about toxoplasmosis, and that higher education levels were significantly associated with knowledge of the disease [14]. In Sri Lanka, T. gondii awareness among pregnant women equaled only 4.4%. Health personnel and media were the sources of information in 46.2% and 53.8%, respectively [15]. Likewise, it was reported that 3/4 of 400 pregnant Saudi women had never heard of toxoplasmosis, and those who lacked that knowledge were at 4.04 times higher risk of toxoplasmosis [16]. Interestingly, only 27.8% of the studied pregnant women in Niterói, Rio de Janeiro claimed to know about toxoplasmosis. Those who were conscious of T. gondii had a significantly lower probability of being seropositive to T. gondii IgG [17].

Previous studies reported that health education of pregnant women might help reduce the risk of congenital toxoplasmosis [10, 18]. Another study performed in Belgium indicated that health education led to a 63% reduction in T. gondii seroconversion [19]. Toxoplasmosis-related ducation of pregnant women in Poland increased their knowledge about the disease and its prevention twice in a 4-year period [20].

The total of 2598 pregnant women from Malaysia, Philippines, and Thailand were randomly surveyed in order to determine their knowledge and practices regarding T. gondii infection. Only 11% of them had read, heard, or seen information regarding toxoplasmosis and only 3.5% were aware of having been tested for the infection [21].

The limitation of our study is the use of close questions in the questionnaire the free-form response was not allowed. Our study included only participants from several centers and certain geographic area and it may not reflect the whole country. The strength of our study is a high number of participants and the fact that it was to our best knowledge the first study on knowledge on toxoplasmosis among the pregnant women in Poland.