Seroprevalence of toxoplasmosis, toxocariasis and cysticercosis in a rural settlement, São Paulo State, Brazil

Risk factors for toxocariasis during incarceration: the One Health intervention approach

Despite potential exposure to soil-transmitted helminths, especially when stray dogs and cats are present, toxocariasis in inmate populations remains to be established. Accordingly, the present study assessed the seroprevalence and associated risk factors of toxocariasis at the Women's State Penitentiary of Parana, Brazil. A total of 234/370 (63.2%; 95% CI 58.2-68.0) women inmates and 28/87 (32.2%; 95% CI 23.3-42.6) correctional officers were seropositive for anti-Toxocara spp. IgG by ELISA, with inmates 2.62-fold more likely positive (p = 0.00000026). The univariate model has identified that non-white (OR = 1.58, p = 0.047) and older than 39 years (OR = 1.28, p = 0.032) inmates were associated with mild but significant odds for seropositivity. Elementary or higher educational level was considered a protective factor for seropositivity. The presence of Toxocara spp. eggs was observed in 10/15 (66.7%) collected soil samples by centrifuge-flotation in Zinc Sulfate, and molecular analysis by PCR identified only Toxocara cati in these eggs. An intervention program was established with regular trap-neuter-release, with gradual removal for adoption (donation campaigns), treatment, and euthanasia when necessary (particularly due to advanced sporotrichosis). In addition, an educational awareness agenda was proposed, aiming to reduce soil contamination and accidental intake by the incarcerated population. A total of 40 feral cats were trapped, 20 males and 20 females, mostly adults. After trapping, 36 cats were neutered, treated, and microchipped in the Veterinary Teaching Hospital (VTH) at the Federal University of Paraná. Five trapped feral cats were euthanized, four diagnosed with advanced sporotrichosis, and one already neutered cat (not herein) with complications due to feline immunodeficiency virus (FIV). Female inmates presented higher seroprevalence for Toxocara spp. antibodies when compared to correctional officers, significantly associated with age, self-declared ethnicity (non-white), and lack of formal education. Despite the non-natural scenario of a state penitentiary, the One Health approach of Toxocara spp. has highlighted the interdisciplinary nature of the study and its relevance in understanding the complex interactions between human, animal, and environmental factors, particularly impacting female inmates. Further studies should establish the rate of inmate infection over time while deprived of liberty.

One Health Approach in Serosurvey of Toxoplasma gondii in Former Black Slave (Quilombola) Communities in Southern Brazil and Among Their Dogs

Brazilian quilombos are rural semi-isolated remnant communities of former black slaves and their descendants who traditionally maintained themselves through archaic subsistence livestock and agriculture practices and historically lacked specific public health policies. Although such individuals and their dogs may be exposed to zoonotic pathogens such as Toxoplasma gondii, no study to date has assessed these human-animal populations together. Populations in four different Brazilian quilombos in southern Brazil were evaluated. Overall, 93/208 people (44.7%) and 63/100 dogs (63.0%) were seropositive for IgG anti-T. gondii antibodies by indirect immunofluorescent antibody test (IFAT), 4/208 (1.9%) human samples seropositive for IgM anti-T. gondii antibodies, with a human-dog seropositivity ratio for IgG of 0.71. Quilombola individuals ingesting game meat were 2.43-fold more likely (95% CI: 1.05-5.9) to be seropositive. No risk factors were associated with seropositivity among dogs, thus suggesting that their exposure to T. gondii was random. Surprisingly, our research group had previously found an inverted human-dog ratio for T. gondii seropositivity of 2.54 in the urban area of a nearby major city. Because consumption of raw/undercooked game meat by quilombola individuals may have contributed to higher exposure, higher overall seroprevalence among dogs may have also indicated interaction with wildlife. Although these dogs may hunt wildlife without their owners' awareness, the higher dog seropositivity may also be related to feeding from discarded food in the community or backyard livestock animals and drinking surface water contaminated with oocysts. Thus, wildlife cannot be singled out as the reason, and future studies should consider sampling water, soil, wildlife, and livestock tissues, to fully establish the source of infection in dogs herein.

Seroprevalence of human toxocariasis in Latin America and the Caribbean: a systematic review and meta-analysis

Introduction

The current study aimed to quantitatively synthesize available evidence regarding the seroprevalence of human toxocariasis in Latin America and the Caribbean.

Methods

A systematic research involving six electronic databases was conducted using a research strategy that combined MeSH terms with free terms. Article selection and information extraction were performed using a double and independent approach. The Newcastle-Ottawa tool was used to assess the risk of bias in the included articles. The meta-analysis used the random-effects approach, with subgroup analysis and sensitivity analysis for risk of bias also being performed.

Results

We included 101 articles with a total of 31,123 participants. The studies were conducted between 1990 and 2022, with Brazil accounting for the largest number of studies (n = 37). The overall seroprevalence of human toxocariasis was 31.0% (95% CI: 27.0-35.0%, I2 = 99%). The prevalence of the main characteristics observed in seropositive patients were as follows: ocular toxocariasis (30.0%), asymptomatic (26.0%), and presence of dogs at home (68.0%). In addition, the seroprevalence was lower in studies including only adults than in those including children or both. In contrast, no differences in seroprevalences were found between studies conducted in the community and hospital.

Conclusion

The overall seroprevalence of human toxocariasis in Latin America and the Caribbean was high. Notably, our findings showed that the seroprevalence was increased among populations who kept a dog at home but was decreased in populations comprising only adults. Our findings can be used to establish epidemiological surveillance strategies for the prevention and early identification of toxocariasis.

Seropositivity to Cysticercosis in School-Age Children Living in a Low-Income Municipality in the Midwest Region of Brazil

Background

Human cysticercosis (CC) is a global public health problem, especially in Latin America, including Brazil. We aimed to analyze the seroprevalence of CC among school-age children and adolescents.

Methods

We analyzed the presence of specific IgG antibodies against Taenia solium metacestodes in 500 serum samples from elementary school children and adolescents in Jataí City, state of Goiás, Brazil. IgG antibodies against the antigenic extract of the parasite were detected and analyzed by ELISA, and specific peptides were identified by confirmatory Western Blotting test.

Results

Of the 500 study participants, 205 (41%) were male, and 295 (59%) were female. Participants aged between 4 and 18 years (mean age 8.4 years). The percentage of serum samples reactive by ELISA was 37.2%. These samples were analyzed by Western Blotting, which confirmed that the seropositivity rate was 6.2% (95% CI 2.4-14.7) in 31 samples reactive for CC-specific bands, determined in serum samples from 18 male (5-11 years old) and 13 female (4-12 years old) students.

Conclusion

The CC seroprevalence demonstrated in schoolchildren suggests that this parasitosis is endemic in the study area. Further investigations are necessary to clarify the local epidemiology of this parasitosis.

Toxocara canis seropositivity in different exposure groups in the Khyber Pakhtunkhwa province of Northwest Pakistan

Human toxocariasis is a highly prevalent zoonosis worldwide but is underreported in most countries. This study was conducted to evaluate Toxocara canis seropositivity in different exposure sub-groups located in the Mardan, Swabi, and Nowshera districts of the Khyber Pakhtunkhwa province of Northwest Pakistan. A total of 400 blood samples were collected from males 15 years of age and older with no animals, with livestock, with dogs and/or cats living in the house, and from butchers and veterinarians or para-veterinarians. Serum was tested using a commercial ELISA kit for detection of IgG antibodies against T. canis. Proportion seropositive was presented for each group and differences between groups were evaluated using the chi-square or Fisher's exact test as appropriate. Possible risk factors obtained through administration of a questionnaire were also evaluated for each sub-population. Overall T. canis seroprevalence was 14.2%, with a significant difference found between the seroprevalence of individuals with no animals (5.0%; 5/100), individuals with dogs and/or cats living in the household (8.0%; 8/100), individuals with livestock (18.0%; 18/100), veterinarians or para-veterinarians (24.0%; 12/50), and butchers (28.0%; 14/50) (p < 0.001). Significant differences in seropositivity by income bracket, education level, and working in the fields were found for some sub-groups. Study findings demonstrate that certain sub-populations, in Northwest Pakistan, may be at greater risk of T. canis infection. Development and implementation of targeted preventive strategies may, therefore, be needed.

Dog and Cat Contact as Risk Factor for Human Toxocariasis: Systematic Review and Meta-Analysis

Toxocariasis, a neglected parasitic zoonosis with worldwide distribution, has been reportedly associated to different risk factors in several epidemiological and meta-analysis studies. However, dog and cat contact (environmental and animal exposure) as isolated associated risk factor for children and adults remains to be fully established. Accordingly, the present meta-analysis has aimed to directly assess dog and cat contact for toxocariasis seropositivity in under-18 and adult persons, using a survey strategy of PubMed/Medline, Embase, Scopus and Scielo Databases, from January 2009 to December 2021. A meta-analysis model of random effects was applied to estimate odds ratio (OR) with 95% Confidence Interval (CI). The statistical heterogeneity was evaluated by the Cochran Q-Test and I² values. A total of 41 transversal studies (n = 20.515 individuals) from different geographic regions (classified by the World Health Organization) were included herein. In overall, 1,882/13,496 (13.95%; 95% IC = 13.4–14.5) youngers and 513/7.019 (7.3%; 95% CI = 6.7–7.9) adults in contact with dogs or cats were serologically reagent for anti-Toxocara antibodies. Association of dog and cat contact was observed only in youngers, with both dogs (OR = 1.53; p < 0.0001) and cats (OR = 1.64; p = 0.0001). In addition, association of dog and contact and serology was statistically significant in populations of Americas (OR = 1.37; 95% CI = 1.1–1.7), Middle East (OR = 2.9; 95% CI = 1.6–5.1) and West Pacific (OR = 1.6; 95% IC = 1.3–1.9). In conclusion, contact with dogs and cats, particularly by younger individuals and in regions such as Americas, Middle East, and West Pacific, should be always a public health concern for toxocariasis. Moreover, dogs and cats should be periodically dewormed, washed and hair cleaned prior to contact with youngers. Finally, robust statistical results herein may serve as basis for future strategies and preventive measures for safer dog and cat contact.

One Health approach on human seroprevalence of anti-Toxocara antibodies, Toxocara spp. eggs in dogs and sand samples between seashore mainland and island areas of southern Brazil

Toxocariasis, caused by Toxocara spp. nematodes, is among the top 5 neglected parasitic diseases worldwide; however, no comprehensive study to date has serologically compared infections in people and their dogs and environmentally contaminated soil or sand of mainland and island locations. Accordingly, this study aimed to assess the seroprevalence of anti-Toxocara antibodies in traditional human seashore populations, the presence of eggs in dogs' feces and hair, and the presence of eggs in environmental samples from islands compared to the adjacent mainland of southern Brazil. Overall, 212/328 (64.6%) people were positive for Toxocara spp. antibodies, including 125/190 (65.8%) island and 87/138 (63.0%) mainland residents. For dog samples, 12/115 (10.43%) were positive for the presence of Toxocara spp. eggs, all from dogs living in islands, and 22/104 (21.15%) dog hair samples contained eggs of Toxocara spp. Environmental contamination with Toxocara spp. eggs was observed in 50/130 (38.46%) samples from all sampled sites. No significant association was found between risk factors (age, sex, educational level, monthly income, owning dogs or cats, ingestion of treated water, and consumption of raw or uncooked meat) and Toxocara spp. seropositivity. The present study is the first concurrent report on people, their dogs, and environmental contamination of Toxocara spp. The high prevalence we observed in the seashore populations of both in island and mainland areas may be caused by exposure to contaminated sand and climatic factors favoring frequent exposure to Toxocara spp. In conclusion, seashore lifestyle and living conditions of both island and mainland areas may have predisposed higher contact with infected pets and contaminated soil, favoring the high prevalence of toxocariasis.

Cases and distribution of visceral leishmaniasis in western São Paulo: A neglected disease in this region of Brazil

Visceral leishmaniasis (VL) is one of the most prevalent parasitic diseases worldwide. In 2019, 97% of the total numbers of cases in Latin America were reported in Brazil. In São Paulo state, currently 17.6% of infected individuals live in the western region. To study this neglected disease on a regional scale, we describe the spread of VL in 45 municipalities of the Regional Network for Health Assistance11(RNHA11). Environmental, human VL (HVL), and canine VL (CVL) cases, Human Development Index, and Lutzomyia longipalpis databases were obtained from public agencies. Global Moran’s I index and local indicators of spatial association (LISA) statistics were used to identify spatial autocorrelation and to generate maps for the identification of VL clusters. On a local scale, we determined the spread of VL in the city of Teodoro Sampaio, part of the Pontal of Paranapanema. In Teodoro Sampaio, monthly peri-domicile sand fly collection; ELISA, IFAT and Rapid Test serological CVL; and ELISA HVL serum surveys were carried out. In RNHA11 from 2000 to 2018, Lu. longipalpis was found in 77.8%, CVL in 69%, and HVL in 42.2% of the 45 municipalities, and 537 individuals were notified with HVL. Dispersion occurred from the epicenter in the north to Teodoro Sampaio, in the south, where Lu. longipalpis and CVL were found in 2010, HVL in 2018, and critical hotspots of CVL were found in the periphery. Moran’s Global Index showed a weak but statistically significant spatial autocorrelation related to cases of CVL (I = 0.2572), and 11 municipalities were identified as priority areas for implementing surveillance and control actions. In RNHA11, a complex array of socioeconomic and environmental factors may be fueling the epidemic and sustaining endemic transmission of VL, adding to the study of a neglected disease in a region of São Paulo, Brazil.

Visceral leishmaniasis (VL) is considered the second most important disease caused by a protozoan worldwide. Currently, 97% of the cases in Latin America are in Brazil. In São Paulo state, since 1997, the disease has been found in an increasing number of municipalities, mainly in the western region. The reasons why VL is spreading in a crescent shape in this region is not well understood, however, socioeconomic and environmental risk factors that increase vulnerability to the disease may be involved. From 2000 to 2018, vectors of Lutzomyia longipalpis were found in 77.8%, canine VL in 69%, and human VL in 44.4% of the 45 municipalities of the western region. Dispersion occurred from the epicenter in the north and followed central and radial highways, reaching Teodoro Sampaio in the south. Among the 45 municipalities, 11 were identified as priority areas for implementing surveillance and control actions. Considered the last frontier and one of the poorest regions of São Paulo, our findings are relevant for planning interventions aimed at reducing the cases of VL in the region.

Human Toxocariasis: 2010 to 2020 Contributions from Brazilian Researchers

This is a review of the published contributions made by Brazilian researchers between 2010 and 2020 on the natural history of human toxocariasis and the effects of human toxocariasis on nonhuman paratenic hosts.

Prevalence and epidemiological characteristics of inmates diagnosed with infectious diseases living in a region with a high number of prisons in São Paulo state, Brazil

OBJECTIVE

To determine the prevalence and epidemiological characteristics of inmates diagnosed with infectious diseases living in a region with a high number of prisons, São Paulo, Brazil.

DESIGN

This is a retrospective and descriptive study conducted from November 2017 to October 2018.

SETTING

Prisons located in the western and northwestern regions of São Paulo, Brazil.

METHODS

We conducted a retrospective analysis on infectious diseases and coinfections (HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), syphilis and tuberculosis (TB)) of inmates from 28 prisons. Inmates were previously diagnosed following the protocol for control and surveillance of infectious diseases, through laboratory or imaging methods. A questionnaire was completed by the healthcare staff. Prevalence was obtained by dividing the number of individuals with positive results by the number of inmates in each prison. Locations of prisons were obtained and maps were constructed using geographic information systems.

RESULTS

A total of 741 of 37 497 inmates (1.97%) were diagnosed with HIV, HBV, HCV, syphilis or TB. HIV was the most prevalent infectious disease (0.68%), followed by TB (0.66%), syphilis (0.2%), HCV (0.2%) and HBV (0.04%). For all of these diseases, prevalence rates varied from very low to high (3.11% and 2.45%) for TB and HIV, respectively, in the five prisons where they were most prevalent. HIV-syphilis was the most associated coinfection (OR, 63.7; 95% CI 41.4 to 96.7). Three of those diagnosed with the infection were female and the ratio of female to men was 0.004:1.

CONCLUSIONS

Our findings demonstrate that the number of cases of infectious disease among inmates in the northwestern and western region of São Paulo is probably underestimated, with lower rates of HCV, HBV and syphilis. This represents a challenge to prisoners' health. Improvements in diagnosis, mainly to reduce viral hepatitis, are crucial with benefits for inmates and the general population.

Seroprevalence and risk factors associated with T. gondii infection in pregnant individuals from a Brazilian Amazon municipality

The aim of this study was to determine the prevalence and to identify the risk factors associated with T. gondii infection in pregnant individuals living in the Ponta de Pedras municipality, Marajó Archipelago, State of Pará, where an outbreak of toxoplasmosis occurred in 2013. From 2014 to March 2017, a cross-sectional study was conducted, including 555 pregnant individuals aged 13- to 42-years-old. Serological tests (enzyme immunoassays) were performed, and socioenvironmental and behavioral information were obtained through the application of a questionnaire. A prevalence of 68.3% was detected, and older age, having contact with soil and living in an urban area were the risk factors associated with seropositivity. The study confirmed the high prevalence of infection among pregnant individuals in the region. The association of the infection with the variables of residential area and contact with soil indicates that there was environmental contamination by T. gondii oocysts in the municipality.

Parasitic Infections of the Stem Cell Transplant Recipient and the Hematologic Malignancy Patient, Including Toxoplasmosis and Strongyloidiasis

Hematopoietic stem cell transplantation (HSCT) recipients may infrequently develop parasitic infections at the time of the procedure via contamination from allograft tissue or blood products, and in the post-transplantation period through the traditional route of infection or as a reactivation caused by immunosuppression related to the transplant. To reduce risk, efforts should be directed at performing a comprehensive history, maintaining a high index of suspicion, and adhering to preventive measures. Additional strategies for the prevention, screening and careful follow-up, identification, and pre-emptive treatment of parasitic infections are required to reduce morbidity and mortality in HSCT patients.

Toxoplasma gondii: seroprevalence and associated risk factors among preschool-aged children in Osun State, Nigeria

Background

Toxoplasma gondii is an ubiquitous apicomplexan parasite, which causes toxoplasmosis in animals and humans worldwide. However, little is known about T. gondii infection among preschool-aged children in Nigeria.

Methods

A cross-sectional study of 272 preschool children aged 2.25±1.09 years from four communities (Edunabon, Erin-Ijesha, Ijebu-jesa and Ile-Ife) in Osun State, Nigeria was conducted between January and July 2016, and the demographic data was obtained via questionnaires. Antibody titres against T. gondii of serum samples were assessed by ELISA.

Results

The overall seroprevalence of T. gondii infection was 6.9% (19/272). There was no significant difference in seroprevalence of T. gondii infection between boys (7.04%; 10/142) and girls (6.92%; 9/130; p=0.97). No associations were found between age, gender, parental educational level, occupation and religion, and T. gondii seropositivity. None showed statistical significance between the risk factors tested after multivariate adjustment; nevertheless, residing in Ijebu-jesa community was shown to be associated with an increased risk of infection (p=0.04).

Conclusion

This is the first report of T. gondii infection among preschool children in Nigeria. Prevalence studies such as this could help in the development of strategies for the future for disease prevention and control of T. gondii transmission.

Seroprevalence of Toxoplasma gondii and Toxocara canis in a human rural population of Southern Rio Grande do Sul

Due to the growing population of pets, especially homeless dogs and cats, zoonoses still represent a significant public health problem. Toxoplasma gondii and Toxocara spp. are epidemiologically important zoonotic agents as they are etiological factors of human toxoplasmosis and toxocariasis, respectively. These parasites remain neglected even though they are substantially prevalent in rural areas. The aim of this study was to investigate T. gondii and T. canis seroprevalence and risk factors of seropositivity in a rural population in Pelotas municipality, Brazil. The study participants (n=344) were patients of a Basic Healthcare Unit (BHU) located in Cerrito Alegre. Blood samples were collected and tested for T. gondii antibodies by indirect immunofluorescence and T. canis antibodies by an indirect ELISA that targets an excreted-secreted antigen (TES). T. gondii seropositivity was 53.2%, with higher titers (1:256 - 1:1,024) in individuals who habitually eat pork, beef, or chicken, while T. canis seropositivity was 71.8% and concomitant T. gondii and T. canis seropositivity was 38.3%. Among the seropositivity risk factors assessed, only habitual undercooked meat consumption was significant (p = 0.046; OR = 3.7) for T. gondii and none of them were associated with T. canis seropositivity. Both parasites have a high prevalence in rural areas, which reinforces the need to invest in rural community education and health.

Seroprevalence of human cysticercosis in Jataí, Goiás state, Brazil

The Taenia solium cysticercosis affects millions of people worldwide and is considered a public health problem, especially in developing countries. The diagnosis of neurocysticercosis is complex and involves the analysis of epidemiological, clinical, neuroimaging, and immunological host data. Neurocysticercosis is endemic in Brazil, and is related to the cause of death mainly in the Southeast, South, and Central-West regions. The objective of this study was to determine the seroprevalence of cysticercosis in inhabitants of the city of Jataí, Goiás, in the Central-West region of Brazil from April to August 2012. A total of 529 serum samples were analyzed by enzyme-linked immunosorbent assay for detecting IgG antibodies against T. solium larvae, and Western blotting was used for confirming the diagnosis through the recognition of at least two specific peptides from their serum antibodies. The 351/529 (66.3%) reactive samples were analyzed by enzyme-linked immunosorbent assay and Western blotting confirmed the diagnosis in 73 samples that recognized at least two of the following peptides specific IgG antibodies for cysticercosis: 18, 24, 28-32, 39-42, 47-52, 64-68, and 70kDa. The seroprevalence of cysticercosis was 13.8% (95% CI 5.9-21.7), demonstrating that the studied area is endemic to this disease.

Seroprevalence of Toxocariasis in Children with Urticaria: A Population-based Study

OBJECTIVE

This study described the prevalence of IgG class antibodies against Toxocara spp. and their association with urticaria in 2- to 12-year-old children.

METHODS

This population-based cross-sectional study was conducted between May 2012 and September 2014. The study sample comprised 168 children. Blood samples were collected to verify the presence of toxocariasis by using ELISA to detect IgG antibodies. The guardians of the children were interviewed to characterize the presence or absence of other diseases, such as urticaria.

RESULTS

The presence of urticaria was observed in 38% of participants. The seroprevalence of toxocariasis in this population was 16%. This study confirmed a positive association between urticaria and positive serology for Toxocara and a negative independent association with canine contact and the number of household residents.

CONCLUSIONS

There are no previous reports in the literature of a population-based study that correlates the presence of urticaria with serology for toxocariasis.

[Seroprevalence and risk factors of cysticercosis in two rural communities in Anzoátegui state, Venezuela]

INTRODUCTION

Cysticercosis is caused by Taenia solium cysticerci, which are located mainly in the central nervous system causing neurocysticercosis. In Venezuela, few epidemiological studies on this disease have been conducted.

OBJECTIVE

To determine the seroprevalence and risk factors for cysticercosis in two rural communities in Anzoátegui state.

MATERIAL AND METHODS

We conducted a survey to collect data on possible risk factors and signs and symptoms of the disease, and we took 182 samples in two communities, Boquerón and Punto Lindo. Detection of IgG antibodies against T. solium cysticerci was performed by ELISA.

RESULTS

Seroprevalence in Boquerón was 3.3%; due to the low number of seropositives the statistical analysis was not possible. However, the three seropositive persons had knowledge of the disease, and a history of consumption of undercooked pork meat, and presence of headache. In Punto Lindo, seroprevalence was 28.9%. There were no significant differences by sex or age; however, we found more seropositives among individuals younger than 20 years. With regard to risk factors and signs and symptoms, significant associations were found with consumption of undercooked pork (OR=18; 95% CI: 5.78 to 55.9), headaches (OR=3.6; 95% CI: 1.15 to 11.4), seizures (OR=18.9; 95% CI: 2.15 to 166.5) and visual problems (OR=5.7; 95% CI: 2.13 to 15.34).

CONCLUSIONS

The results showed low transmission of cysticercosis in Boquerón, and high in Punto Lindo, where the high prevalence in children suggests recent transmission.

Seroepidemiology of toxoplasmosis in rural and urban communities from Los Rios Region, Chile

Background

Toxoplasmosis is a prevalent protozoan infection with a complex lifecycle and wide profile of risk factors. The impact of congenital infection is well documented; however, there is increasing evidence of a much broader range of potential health outcomes and the need to improve our understanding of the transmission patterns and infection sources in the overall population. This study examined the epidemiology of toxoplasmosis in distinct community types from a highly endemic area of Chile.

Methods

A cross-sectional serosurvey was carried out in households from urban slums, rural villages, and farms which included collection of blood samples, as well as data on sociodemographic, behavioral, and spatial variables. Blood samples were analyzed for the presence of T. gondii-specific IgG antibodies. Avidity index was obtained for IgG-positive samples. Mixed-effects regression modeling was used to identify associations with relevant risk factors.

Results

Crude seroprevalence was 55.9% (95% CI: 52.6–59.1%) with no difference by community type. Results are indicative of early exposure to the parasite, including 40% of 13- to 17-year olds who were already seropositive. Sociodemographic factors associated with seropositivity included age, occupations, and income. However, sex modified the effect of occupation as well as of income. Practices associated with increased seropositivity were consumption of sheep and locally produced vegetables as well as cleaning household barns or sheds. Boiling water for household use was a protective factor. Living on a sloped terrain without vegetation was a protective factor, while living in an area with high flow accumulation index was a risk factor.

Conclusions

Seroprevalence of infection was high in both rural and urban slum communities with unique risk factor profiles for each community type. Findings highlight the role of the household and the community environment as influential factors in the epidemiology of the infection. Increasing awareness is needed at the health care and public health levels to establish disease burden and options for suitable control programs.

A Systematic Review of Toxocariasis: A Neglected But High-Prevalence Disease in Brazil

Toxocariasis is an anthropozoonosis that occurs in all parts of the world. In particular, this disease can often be found in developing countries and in regions, where basic sanitation conditions are poor. However, industrialized countries have reported seroprevalence rates as high as 14.2% in humans. The definitive hosts of the disease are dogs and cats, whereas humans are a paratenic host. To determine the burden of toxocariasis in Brazil, we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines to conduct a systematic review of the literature. Using keywords and applying the established criteria, we identified 160 publications and selected 22 articles for further analysis. The seroprevalence of toxocariasis in various regions of the country ranged from 4.2% to 65.4%. The highest prevalence was found in the northeast region, although the majority of the studies identified were from the southeast region. The findings suggest the importance of raising awareness among health professionals and public authorities about the fact that toxocariasis is a health problem.

Toxoplasma gondii infection: seroprevalence and associated risk factors among primary school children in the capital area of the Republic of the Marshall Islands

Although Toxoplasma gondii infection is commonly prevalent in the tropical/subtropical regions, the prevalence of toxoplasmosis in the Republic of the Marshall Islands (RMI) remains unclear. A seroepidemiological survey was undertaken for investigating T. gondii infection in primary school children (PSC) using the latex agglutination (LA) test in the capital area of RMI. Information on demographic characteristics and environmental risk factors was collected via a structured questionnaire. Logistic regression model was applied for multivariate analysis. The overall infection rate of T. gondii was found to be 54.8%. Significant gender differences were found at different urbanization levels. PSC with LA titers of ≥ 1:1,024, indicating high responders, were found to be younger age group than others (8.7 years vs. 10.3 years, P = 0.003); moreover, infection rates among both age groups as well as high responders showed a decreasing trend with age. Multivariate analysis revealed that residing in urban rather than suburban settings was associated with increased risk of infection (P = 0.04). No associations were found between raw meat consumption, drinking unboiled water, and cleaning of cat hutch using gloves. This is the first serological survey of T. gondii infection among PSC in RMI and could help in the development of strategies in the future for disease prevention and control of T. gondii transmission.