Endemicity of Toxoplasma infection and its associated risk factors in Cebu, Philippines

Abstract

Toxoplasma gondii is a single-celled intracellular apicomplexan parasite that causes toxoplasmosis. It is capable of infecting humans and nearly all warm-blooded animals including pigs, but cats are the only known definitive host. This ubiquitous zoonotic pathogen can cause abortion, stillbirth and fetal abnormalities, and has been associated with mental and behavioral changes in humans. Acute infection is potentially fatal in immunocompromised individuals. The present study aimed to assess the Toxoplasma seroprevalence in pigs, humans and cats after its initial reported detection in pigs about three decades ago in Cebu, Philippines. A total of 924 humans, 104 cats and 514 slaughter pigs were tested for antibodies against T . gondii using a commercial latex agglutination test. The results revealed positive detection rates of 26.3% (244/924) for humans, 42.3% (44/104) for cats and 13.4% (69/514) for slaughter pigs. Statistical analyses revealed that the area (P = 0.004), cat ownership ( P = 0.020), the frequency of contact with cats ( P < 0.0001) and consumption of street foods ( P = 0.043) were significantly associated with seropositivity for T . gondii in humans. Meanwhile, the use of litter trays ( P = 0.001) and contact with other animals ( P = 0.007) were significantly associated with seropositivity in cats. The odds ratio for selected significant factors revealed that living in suburban areas (OR 1.66, 95% CI: 1.20–2.31), owning a cat (OR 1.482, 95% CI: 1.07–2.07) and eating street foods (OR 1.585, 95% CI: 1.01–2.48) were associated with an increased risk of T . gondii exposure in humans. In cats, the use of a litter tray (OR 4.5, 95% CI: 1.73–11.71) was associated with an increased risk of exposure. None of the profile parameters were found to be significantly associated with seropositivity in slaughter pigs ( P > 0.05). This study is the first report of the serological detection of T . gondii in humans and cats in Cebu, Philippines, and the first assessment of the prevalence of the parasite in pigs in the area since its initial detection in 1982. This is also the first report documenting the seropositivity of T . gondii in pregnant women in the country. The confirmed seropositivity of T . gondii in Cebu, Philippines, in the present study implies the endemicity of toxoplasmosis in this area and highlights the need for routine testing and increased public awareness.

Cross-sectional survey for Toxoplasma gondii infection in humans in Fernando de Noronha island, Brazil

“…This is the first epidemiological study of T. gondii infection in humans on the island of Fernando de Noronha. The seroprevalence of antibodies found in human on this island (50.4%) differs from the prevalence rates found in other insular environments in different regions of the world: Islands of Jeju (ELISA: 13.2%) (Hong et al, 2011) and Gangwha-gun (ELISA: 25.8%) (Yang et al, 2012), both in South Korea, Island of Cebu, in the Philippines (Latex Agglutination Test -LAT: 26.4%) (Ybañez et al, 2019) Island of Sri Lanka (ELISA: 29.9%) (Iddawela et al, 2017), Island of Pulau Pangkor, Malaysia (ELISA: 59.7%) (Ahmad et al, 2014), Island of São Tomé and Príncipe, in West Africa (LAT: 63.1%) (Fan et al, 2012), Island of Granada (ELISA: 57%) (Asthana et al, 2006), and 10 island countries (Modified Agglutination Test -MAT: 39.8%) (Dubey et al, 2016), located in the Caribbean, San Carlos Island, Venezuela (Indirect Haemagglutination Assay-IHA, 49.8%) (Chacín-Bonilla et al, 2003).…”

Infection with Toxoplasma gondii increases the risk of psychiatric disorders in Taiwan: a nationwide population-based cohort study

“…Regional differences in seroprevalence can range from 10 to 80% (Robert-Gangneux and Darde, 2012), but the lack of systematic reporting of seropositivity makes it difficult to understand associated risk factors (Pappas et al ., 2009). Although T. gondii infection is found in many warm-blooded animals, domestic cats are the definitive host (Chiang et al ., 2014; Achaw et al ., 2019; Ybanez et al ., 2019). Numerous studies demonstrated that all cats in the world can shed T. gondii oocytes in feces, leading to environmental contamination and public health threats (Dabritz and Conrad, 2010; Berger-Schoch et al ., 2011; Lilly and Wortham, 2013; Zulpo et al ., 2018).…”

“…However, immunocompromised individuals such as those with HIV/AIDS (Hung et al ., 2005), those undergoing chemotherapy or transplant recipients (Dubey and Jones, 2008) and neonates (Hu et al ., 2006), may develop serious complications such as seizures, encephalitis or lung disease resembling tuberculosis. Notably, studies from around the world have reported associations between toxoplasma seropositivity and psychiatric disorders, such as psychosis, schizophrenia, bipolar disorder, major depression and anxiety (Lindgren et al ., 2018; Achaw et al ., 2019; Palerme et al ., 2019; Stepanova et al ., 2019; Ybanez et al ., 2019). However, inconsistent and even controversial results were reported.…”

The first seroepidemiological study on Toxoplasma gondii in backyard pigs in Myanmar

“…Reports from some Asian countries showed as 5.2%–17.5% in Nepal ( Devleesschauwer et al, 2013 ) and 13.8% in China ( Zhang et al, 2020 ) using ELISA, and 27.2% in Vietnam ( Huong and Dubey, 2007 ) tested by MAT (modified agglutination test). In addition, using LAT method, seroprevalence of T. gondii in pigs was higher in Myanmar than in other Asian countries, including Indonesia (2.3%) ( Tuda et al, 2017 ), Japan (5.2%) ( Matsuo et al, 2014 ), and the Philippines (13.4%) ( Ybañez et al, 2019 ). However, it was lower than those in South Africa (33.9%) ( Tagwireyi et al, 2019 ) and Nigeria (46.2%) ( Ishaku et al, 2018 ) tested by LAT.…”