Cat Litter and Pregnancy: Toxoplasma Parasite Found in Over 40 Percent of Ghanaian Mothers

A single-celled parasite that infects an estimated one-third of the human population has emerged as a substantial and previously underappreciated threat to pregnant women in eastern Ghana. A new cross-sectional study conducted at Ho Teaching Hospital in the Volta Region has found that 42.5 percent of expectant mothers attending their first antenatal care visit carry antibodies against Toxoplasma gondii, the obligate intracellular protozoan responsible for toxoplasmosis. The finding, published in BMC Infectious Diseases, places the Volta Region among the areas of Ghana with the highest recorded exposure to this silent pathogen and raises urgent questions about whether routine screening for the parasite should become part of standard antenatal care in the country.

Toxoplasma gondii is one of the most successful parasites on Earth. Its definitive hosts are members of the cat family, in whose intestines the organism undergoes sexual reproduction and sheds hardy oocysts into the environment through feces. These oocysts can survive in soil and water for months, resisting heat and desiccation, and are readily taken up by warm-blooded intermediate hosts, including humans. Infection in people typically occurs through three principal routes: ingestion of oocysts contaminating food, water, or soil; consumption of undercooked meat containing tissue cysts; and, critically for pregnancy, transplacental transmission from an acutely infected mother to her unborn child. In healthy adults, the infection is usually asymptomatic or produces a mild, flu-like illness that passes unnoticed. The immune system walls the parasite off in dormant tissue cysts, where it can persist for life. But in pregnancy, and in immunocompromised individuals, the stakes change dramatically.

When a woman acquires a primary T. gondii infection during gestation, the parasite can cross the placenta and invade fetal tissues, causing congenital toxoplasmosis. The consequences range from miscarriage and stillbirth to severe neurological damage, hydrocephalus, chorioretinitis leading to vision loss, and calcifications in the brain. The risk of transmission and the severity of disease depend heavily on the timing of infection: early in pregnancy, transmission is less likely but fetal damage, when it occurs, tends to be catastrophic, while later infection transmits more readily but often produces milder, sometimes delayed manifestations such as hearing loss or retinal disease diagnosed years after birth. This is precisely why serological surveillance of pregnant women matters. Knowing how many women have already been exposed, and therefore which mothers remain susceptible to a primary infection, allows health systems to target education and, where appropriate, diagnostic follow-up.

The research team, led by Verner Ndudiri Orish of the University of Health and Allied Sciences in Ho and including investigators from the University of Ghana, Ho Teaching Hospital, the Ghana Atomic Energy Commission, and collaborating institutions, enrolled 201 pregnant women aged 15 to 49 years who were attending their first antenatal care visit between 24 February and 7 April 2025. Consecutive sampling was used to minimize selection bias, and each participant completed a validated questionnaire covering sociodemographic characteristics, obstetric history, dietary practices, and environmental exposures, including contact with cats. Blood samples were collected in EDTA tubes and screened for T. gondii-specific immunoglobulin G and immunoglobulin M antibodies using a rapid diagnostic test. Statistical analysis was performed with IBM SPSS Statistics version 27, with logistic regression models used to identify independent predictors of seropositivity at a 95 percent confidence interval and a significance threshold of p less than 0.05.

The headline result was stark: 85 of the 201 women, or 42.5 percent, tested positive for T. gondii antibodies. The overwhelming majority of these infections, 96.5 percent, were IgG-only, indicating past exposure and the presence of dormant tissue cysts rather than active disease. Just 3.5 percent of seropositive women carried both IgG and IgM, a pattern that can suggest a recent or reactivated infection and would warrant closer clinical attention. An IgG-dominant profile means that most of the exposed women have already mounted an immune response that substantially reduces the risk of transmitting the parasite to a future fetus. However, the sheer proportion of women exposed before or during early reproductive life also means that a large fraction of the remaining population, more than half of the study cohort, remains susceptible to a primary infection, which is the scenario most dangerous for the developing fetus.

The regression analysis yielded two striking risk factors. The first was parity, the number of times a woman has previously given birth. Compared with nulliparous women, those pregnant with their first child, the primiparous group, had nearly four times the odds of seropositivity, with an adjusted odds ratio of 3.93 and a 95 percent confidence interval of 1.42 to 10.91. Multiparous women showed a similarly elevated odds ratio of 3.85, with a confidence interval of 1.50 to 9.87. This association is intriguing because it runs counter to a simple cumulative-exposure model, in which more years of life would be expected to translate into more opportunities for infection. The authors’ finding suggests that in this setting, parity may serve as a proxy for other exposures, such as household food-handling practices, rural environmental contact, or caregiving patterns that bring women into contact with contaminated soil or animals. Whatever the underlying mechanism, the signal was robust enough to survive adjustment for other variables in the model.

The second and perhaps most actionable risk factor was the handling of cat litter. Women who reported cleaning cat litter had more than seven times the odds of being seropositive compared with those who did not, with an adjusted odds ratio of 7.43 and a confidence interval of 2.06 to 26.76. This result aligns precisely with the parasite’s biology. Cats shed T. gondii oocysts in their feces, particularly after a recent primary infection, and these oocysts require one to five days in the environment to sporulate and become infectious. Litter boxes that are not cleaned daily therefore accumulate sporulated, infective oocysts, and the act of scooping them generates aerosols and dust that can be inhaled or transferred to the hands and mouth. The strong statistical association observed in Ho provides direct epidemiological confirmation of a transmission route that public health authorities in high-income countries have long emphasized in pregnancy advice: pregnant women should avoid changing cat litter altogether, or if they must, wear gloves and wash their hands thoroughly afterward.

The Ho findings sit within a broader African and Ghanaian context of remarkably high toxoplasmosis burden. Regional studies across Ghana have previously reported elevated seroprevalence among pregnant women, but data from the Volta Region specifically have been sparse, leaving a gap in the national picture. The new study fills that gap with a figure that exceeds many reported estimates from other parts of the world, where seroprevalence in pregnant women can range from under 10 percent in some northern European countries with strict food-safety and hygiene norms to over 50 percent in parts of Latin America and sub-Saharan Africa. High seroprevalence in a tropical setting is shaped by a convergence of factors: warm, humid climates that favor oocyst survival in soil; free-roaming cat populations; dietary practices that may include undercooked or improperly washed foods; limited access to clean water; and the absence of routine screening programs that would otherwise identify and counsel susceptible women.

The study’s implications for antenatal care policy in Ghana are considerable. Currently, toxoplasmosis is not part of routine antenatal screening in most Ghanaian facilities, where programmatic attention has understandably focused on HIV, malaria, syphilis, and anemia. Yet the biology of congenital toxoplasmosis makes a compelling case for at least targeted screening. Women who test IgG-negative at their first visit are the ones at genuine risk of a primary infection during pregnancy, and they are the ones who would benefit most from intensive hygiene counseling: avoiding cat litter, washing fruits and vegetables meticulously, cooking meat thoroughly, wearing gloves when gardening, and washing hands after contact with soil or raw meat. For women with IgG and IgM co-positivity, confirmatory testing, ideally with reference laboratory methods such as enzyme-linked immunosorbent assay and avidity testing, could distinguish recent from distant infection and guide decisions about treatment with spiramycin or pyrimethamine-based regimens, which can reduce the risk and severity of fetal transmission when initiated promptly.

The authors emphasize that their findings underscore the need for routine health education, improved hygienic practices, and serious consideration of toxoplasmosis screening within antenatal care programs to reduce maternal-fetal complications. The study received no external funding and was supported entirely by the investigators, and it was conducted with ethical clearance from the University of Health and Allied Sciences Research Ethics Committee under the principles of the Declaration of Helsinki, with written and verbal informed consent obtained from all participants. As a single-center cross-sectional study relying on rapid diagnostic tests rather than confirmatory serology, it has inherent limitations, including the potential for false-positive or false-negative results and the inability to establish causality between the identified risk factors and infection. Nevertheless, the message it delivers is difficult to ignore. In Ho Municipality, more than four in ten expectant mothers carry a parasite that most have never heard of, and the simple act of cleaning a cat’s litter box multiplies the odds of exposure sevenfold. Closing that knowledge gap, through education, hygiene interventions, and a renewed conversation about what belongs in the antenatal care package, could spare countless families the devastating and largely preventable consequences of congenital toxoplasmosis.

Subject of Research: Seroprevalence and risk factors of Toxoplasma gondii infection among pregnant women in the Volta Region of Ghana

Article Title: Seroprevalence of Toxoplasma gondii among pregnant women seeking antenatal care in Ho Municipality of the Volta Region of Ghana

Article References: Orish, V. N., Matthew, D., Ablordey, K., Squire, D. S., Arko-Mensah, J., De-graft Tawiah, J., Tsadidey, E., Adzah, D., Yeboah, E. A., Tetteh, R. E., Vikpebah, D. R., Nwaefuna, E. K., Lopez, D. M., Dah, A. K., Amoh, M., & Abaka-Yawson, A. (2026). Seroprevalence of Toxoplasma gondii among pregnant women seeking antenatal care in Ho Municipality of the Volta Region of Ghana. BMC Infectious Diseases. https://doi.org/10.1186/s12879-026-14593-9

Image Credits: AI Generated

DOI: 10.1186/s12879-026-14593-9

Keywords: Toxoplasma gondii, toxoplasmosis, pregnant women, seroprevalence, Ghana, antenatal care, congenital infection, cat litter, parasitology, public health, Volta Region, rapid diagnostic test