Risk Factors for Toxoplasma gondii Infection in Pregnancy: Results of a Prospective Case-Control Study in Norway

Abstract

From 1992 to 1994, a prospective case-control study designed to identify preventable risk factors for Toxoplasma gondii infection in pregnancy was conducted in Norway. Case-patients were identified through a serologic screening program encompassing 37,000 pregnant women and through sporadic antenatal testing for Toxoplasma infection. A total of 63 pregnant women with serologic evidence of recent primary T. gondii infection and 128 seronegative control women matched by age, stage of pregnancy, expected date of delivery, and geographic area were enrolled. The following factors were found to be independently associated with an increased risk of maternal infection in conditional logistic regression analysis (in order of decreasing attributable fractions): 1) eating raw or undercooked minced meat products (odds ratio (OR) = 4.1, p = 0.007); 2) eating unwashed raw vegetables or fruits (OR = 2.4, p = 0.03); 3) eating raw or undercooked mutton (OR = 11.4, p = 0.005); 4) eating raw or undercooked pork (OR = 3.4, p = 0.03); 5) cleaning the cat litter box (OR = 5.5, p = 0.02); and 6) washing the kitchen knives infrequently after preparation of raw meat, prior to handling another food item (OR = 7.3, p = 0.04). In univariate analysis, travelling to countries outside of Scandinavia was identified as a significant risk factor, but this variable was not independently associated with infection after data were controlled for factors more directly related to the modes of infection.

Factors associated to infection by Toxoplasma gondii in pregnant women attended in Basic Health Units in the city of Rolândia, Paraná, Brazil

“…Studies have shown the importance of this factor, such as CADEMARTORI et al (2008) 12 who carried out a study with pregnant women in Pelotas, Rio Grande do Sul, and found high positive rates among those who handled raw meat. KAPPERUD et al (1996) 33 carried out a case-control study in Norway and related the low frequency in washing kitchen knives after preparing raw meat and before preparing another food to the risk of infection by T. gondii during pregnancy.…”

Prevalence of acute toxoplasmosis infection among 41,112 pregnant women and the mother-to-child transmission rate in a public hospital in South Brazil

“…In Brazil, the Southern region, where this study was conducted, has a low prevalence of toxoplasmosis among pregnant women (Nobrega & Karnikowski 2005, Figueiro-Filho et al 2007. However, there is substantial variability in the reported data, depending on chosen population, diagnostic methods used in screening, or even the different risk factors involved in disease transmission (Buffolano et al 1996, Kapperud et al 1996, Cook et al 2000, Jones et al 2001.…”

Risk factors for acute toxoplasmosis in England and Wales

“…Toxoplasmosis can be acquired in humans by: (i) ingesting sporulated oocysts from the environment, usually from soil, fruit or vegetables, or from water contaminated with feline faeces; (ii) ingesting cysts in food produced from an infected animal; (iii) vertical transmission from an infected mother to her fetus; (iv) blood transfusion or organ transplantation; and (v) ingesting the parasite following direct contact with products of conception during lambing [1,[4][5][6][7][8].…”