Abstracts

INTRODUCTION

Infection with Toxoplasma gondii is common all over the world, making it one of the most common infections in humans. ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 18}18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... ^{, 21}21 . Tenter AM, Heckeroth AR, Weiss LM. Toxoplasma gondii: from animals to humans. Int J Parasitol. 2000;30(12-13):1217-58. DOI:10.1016/S0020-7519(00)00124-7
https://doi.org/10.1016/S0020-7519(00)00... Although the evolution of primary infection is usually with slight signs/symptoms, the majority of the human population infected remains asymptomatic. ³3 . Dubey JP, Jones JL. Toxoplasma gondii infection in humans and animals in the United States. Int J Parasitol. 2008;38(11):1257-78. DOI:10.1016/j.ijpara.2008.03.007
https://doi.org/10.1016/j.ijpara.2008.03... ^{, 13}13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... The infection may cause an additional burden of morbidity and mortality in certain populations, ¹⁸18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... as in fetuses of pregnant women with acute infection ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... and people with compromised immunological response. ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 14}14 . Nissapatorn V. Toxoplasmosis in HIV/AIDS: a living legacy. Southeast Asian J Trop Med Public Health. 2009;40(6):1158-78. ^{, 23}23 . Zumla A, Savva D, Wheeler RB, Hira SK, Luo NP, Kaleebu P, et al. Toxoplasma serology in Zambian and Ugandan patients infected with the human immunodeficiency virus. Trans R Soc Trop Med Hyg. 1991;85(2):227-9. DOI:10.1016/0035-9203(91)90034-V
https://doi.org/10.1016/0035-9203(91)900...

Meningoencephalitis caused by reactivated toxoplasmosis is one of the most common neurological opportunistic infections in patients with HIV infection/AIDS and is typically observed in advanced stages of the disease. ¹⁶16 . Perez-Hoyos S, Naniche D, Macete E, Aponte J, Sacarlal J, Sigauque B, et al. Stabilization of HIV incidence in women of reproductive age in Southern Mozambique. HIV Med. 2011;12(8):500-5. DOI:10.1111/j.1468-1293.2010.00908.x
https://doi.org/10.1111/j.1468-1293.2010... The high burden of opportunistic infections with T. gondii , especially in immunocompromised individuals, mainly verified from 1980s, remains a significant public health problem in some countries, especially those that have failed to gain universal access to highly active antiretroviral therapy (HAART). ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... ^{, 4}4 . Falusi O, French AL, Seaberg EC, Tien PC, Watts DH, Minkoff H, et al. Prevalence and predictors of Toxoplasma seropositivity in women with and at risk for human immunodeficiency virus infection. Clin Infect Dis. 2002;35(11):1414-7. DOI:10.1086/344462
https://doi.org/10.1086/344462...

The primary acquisition mode occurs mainly by ingestion of raw or undercooked meat of intermediate hosts containing viable tissue cysts, or by ingesting food and water contaminated with sporulated oocysts from the environment, existing and originating in cat faeces. ¹⁸18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... Close contact between humans and pets, especially dogs and cats, can generate situations of greater vulnerability to human infection. ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 21}21 . Tenter AM, Heckeroth AR, Weiss LM. Toxoplasma gondii: from animals to humans. Int J Parasitol. 2000;30(12-13):1217-58. DOI:10.1016/S0020-7519(00)00124-7
https://doi.org/10.1016/S0020-7519(00)00... There is also the possibility of transmission of tachyzoites in utero through the placenta or by ingestion of tachyzoites in non-pasteurized goat milk. T. gondii can also be transmitted by blood components, by solid organ transplants. ²¹21 . Tenter AM, Heckeroth AR, Weiss LM. Toxoplasma gondii: from animals to humans. Int J Parasitol. 2000;30(12-13):1217-58. DOI:10.1016/S0020-7519(00)00124-7
https://doi.org/10.1016/S0020-7519(00)00...

Not all possible routes of infection are currently epidemiologically important, and sources of infection may vary greatly among different ethnic groups and geographical locations. ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 22}22 . Uneke CJ, Duhlinska DD, Njoku MO, Ngwu BA. Seroprevalence of acquired toxoplasmosis in HIV-infected and apparently healthy individuals in Jos, Nigeria. Parassitologia . 2005;47(2):233-6. This happens especially in environments with characteristics of rural life, which increase the risk of infection. ⁸8 . Hill D, Dubey JP. Toxoplasma gondii: transmission, diagnosis and prevention. Clin Microbiol Infect. 2002;8(10):634-40. DOI:10.1046/j.1469-0691.2002.00485.x
https://doi.org/10.1046/j.1469-0691.2002... ^{, 11}11 . Marques JM, da Silva DV, Correia NAB, Velásquez G, da Silva RC, Langoni H, et al. Prevalence and risk factors for human toxoplasmosis in a rural community. J Venom Anim Toxins Incl Trop Dis. 2008;14(4):673-84. DOI:10.1590/S1678-91992008000400010
https://doi.org/10.1590/S1678-9199200800... ^{, 13}13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16...

Its incidence has a direct relationship with the prevalence of anti- T.gondii in the general population or in populations with greater vulnerability. ¹1 . Brindle R, Holliman R, Gilks C, Waiyaki, P. Toxoplasma antibodies in HIV-positive patients from Nairobi. Trans R Soc Trop Med Hyg. 1991;85(6):750-1. DOI:10.1016/0035-9203(91)90443-3
https://doi.org/10.1016/0035-9203(91)904... The prevalence of latent infection with toxoplasmosis is between 30% and 60% in most countries, varying widely in different regions of the world. ⁵5 . Gille E, Björkman A, Rooth I, Ljungström I, Linder E. Low seroprevalence of Toxoplasma gondii antibodies in a Tanzanian village. Trans R Soc Trop Med Hyg. 1992;86(3):263-5. DOI:10.1016/0035-9203(92)90303-T
https://doi.org/10.1016/0035-9203(92)903... ^{, 10}10 . Lindström I, Kaddu-Mulindwa DH, Kironde F, Lindh J. Prevalence of latent and reactivated Toxoplasma gondii parasites in HIV-patients from Uganda. Acta Trop. 2006;100(3):218-22. DOI:10.1016/j.actatropica.2006.11.002
https://doi.org/10.1016/j.actatropica.20... ^{, 11}11 . Marques JM, da Silva DV, Correia NAB, Velásquez G, da Silva RC, Langoni H, et al. Prevalence and risk factors for human toxoplasmosis in a rural community. J Venom Anim Toxins Incl Trop Dis. 2008;14(4):673-84. DOI:10.1590/S1678-91992008000400010
https://doi.org/10.1590/S1678-9199200800... Despite its importance, few studies on the prevalence have been conducted in sub-Saharan Africa. ⁷7 . Hari KR, Modi MR, Mochan AH, Modi G. Reduced risk of toxoplasma encephalitis in HIV-infected patients-a prospective study from Gauteng, South Africa. Int J STD AIDS. 2007;18(8):555-8. DOI:10.1258/095646207781439829
https://doi.org/10.1258/0956462077814398... ^{, 9}9 . Hotez PJ, Kamath A. Neglected tropical diseases in sub-saharan Africa: review of their prevalence, distribution, and disease burden. PLoS Negl Trop Dis. 2009;3(8):e412. DOI:10.1371/journal.pntd.0000412
https://doi.org/10.1371/journal.pntd.000... ^{, 10}10 . Lindström I, Kaddu-Mulindwa DH, Kironde F, Lindh J. Prevalence of latent and reactivated Toxoplasma gondii parasites in HIV-patients from Uganda. Acta Trop. 2006;100(3):218-22. DOI:10.1016/j.actatropica.2006.11.002
https://doi.org/10.1016/j.actatropica.20... ^{, 20}20 . Shimelis T, Tebeje M, Tadesse E, Tegbaru B, Terefe A. Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: a comparative cross-sectional study. BMC Res Notes. 2009;2:213. DOI:10.1186/1756-0500-2-213
https://doi.org/10.1186/1756-0500-2-213...

There are frequent reports of congenital toxoplasmosis or toxoplasmic meningoencephalitis in patients with AIDS in Mozambique, but the real situation is unknown, with a small number of publications. ¹⁹19 . Sitoe SPBL, Rafael B, Meireles LR, Andrade Jr HF, Thompson R. Preliminary report of HIV and Toxoplasma gondii occurrence in pregnant women from Mozambique. Rev Inst Med Trop Sao Paulo. 2010;52(6):291-5. DOI:10.1590/S0036-46652010000600002
https://doi.org/10.1590/S0036-4665201000... The paucity of reliable information on risk factors, main means of transmission and of preventative measures used, is of concern not only for researchers, ⁹9 . Hotez PJ, Kamath A. Neglected tropical diseases in sub-saharan Africa: review of their prevalence, distribution, and disease burden. PLoS Negl Trop Dis. 2009;3(8):e412. DOI:10.1371/journal.pntd.0000412
https://doi.org/10.1371/journal.pntd.000... ^{, 18}18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... ^{, 22}22 . Uneke CJ, Duhlinska DD, Njoku MO, Ngwu BA. Seroprevalence of acquired toxoplasmosis in HIV-infected and apparently healthy individuals in Jos, Nigeria. Parassitologia . 2005;47(2):233-6. but for society in general. Considering the scale of AIDS in Mozambique ⁶6 . González R, Munguambe K, Aponte J, Bavo C, Nhalungo D, Macete E, et al. High HIV prevalence in a southern semi-rural area of Mozambique: a community-based survey. HIV Med. 2012;13(10):581-8. DOI:10.1111/j.1468-1293.2012.01018.x
https://doi.org/10.1111/j.1468-1293.2012... ^{, 12}12 . Maueia C, Costa D, Meggi B, Ismael N, Walle C, Curvo R, et al. Frequency of human immunodeficiency virus type-2 in hiv infected patients in Maputo City, Mozambique. Virol J. 2011;8(1):408. DOI:10.1186/1743-422X-8-408
https://doi.org/10.1186/1743-422X-8-408... ^{, 16}16 . Perez-Hoyos S, Naniche D, Macete E, Aponte J, Sacarlal J, Sigauque B, et al. Stabilization of HIV incidence in women of reproductive age in Southern Mozambique. HIV Med. 2011;12(8):500-5. DOI:10.1111/j.1468-1293.2010.00908.x
https://doi.org/10.1111/j.1468-1293.2010... and the vulnerability of HIV-infected people with toxoplasmosis, there is a clear need for further studies on this subject. ¹⁰10 . Lindström I, Kaddu-Mulindwa DH, Kironde F, Lindh J. Prevalence of latent and reactivated Toxoplasma gondii parasites in HIV-patients from Uganda. Acta Trop. 2006;100(3):218-22. DOI:10.1016/j.actatropica.2006.11.002
https://doi.org/10.1016/j.actatropica.20... ^{, 14}14 . Nissapatorn V. Toxoplasmosis in HIV/AIDS: a living legacy. Southeast Asian J Trop Med Public Health. 2009;40(6):1158-78.

This study aimed to analyze the prevalence of IgG antibodies to Toxoplasma gondii in patients infected by HIV/AIDS and the association of demographic and social variables in Maputo, Mozambique.

METHODS

Descriptive cross-sectional study with patients infected by HIV/AIDS, who were treated at a reference center in Maputo, Mozambique, in the second half of 2010.

The study was conducted in the Maputo Military Hospital (HMM) in the city of Maputo. This is a quaternary level health unit and a national reference between the military hospitals of Mozambique. The HMM, with four infirmaries and 220 bed capacity, provides medical assistance to the Defense and Security Forces and Veterans of the National Liberation Resistance, including members of their families. It has an emergency room, operating room services, physical therapy, radiology, ophthalmology, dentistry, and a clinical laboratory and a special examination room.

The Laboratory of HMM has a samples receiving unit, blood collection room, sections serology, microbiology/ parasitology, hematology, biochemistry and molecular biology (especially designed to assist people living with HIV/AIDS).

The target population consisted of all patients infected by HIV, aged over 18 years old, male and female, who visited the laboratory of HMM, the serology section. Recruitment was carried out during routine follow-up and during initial visits. Patients who met the inclusion criteria and signed consent were recruited consecutively. A sample was drawn from this population and a cross-sectional survey was conducted. Data collection occurred between September and November 2010.

HIV diagnosis is available through voluntary counseling and testing (VCT) centers in Mozambique. Rapid tests are used to provide clients with an immediate result. HIV positive clients are referred to the Central Hospital for assessment and antiretroviral therapy (ART) is initiated. Based on the 2010 WHO staging ²⁵25 . World Health Organization. Antiretroviral Therapy for HIV Infection in Adults and Adolescents: Recommendations for a public health approach 2010 revision. Geneva; 2010. national treatment guidelines, initiation of ART is recommended to all adolescents and adults including pregnant women with HIV infection and CD4 counts of ≤ 350 cells/mm ³3 . Dubey JP, Jones JL. Toxoplasma gondii infection in humans and animals in the United States. Int J Parasitol. 2008;38(11):1257-78. DOI:10.1016/j.ijpara.2008.03.007
https://doi.org/10.1016/j.ijpara.2008.03... , regardless of the presence or absence of clinical symptoms. Those with severe or advanced clinical disease (including AIDS) should start ART irrespective of their CD4 T-cell count.

The definition of AIDS in Mozambique is the clinical diagnosis (presumptive or definitive diagnosis) of any stage 4 condition or CD4 T-cell count < 200 cells/mm ³3 . Dubey JP, Jones JL. Toxoplasma gondii infection in humans and animals in the United States. Int J Parasitol. 2008;38(11):1257-78. DOI:10.1016/j.ijpara.2008.03.007
https://doi.org/10.1016/j.ijpara.2008.03... of blood in a HIV-infected adults.

Two hundred HIV/AIDS seropositive patients agreed to participate in the study. Self-administered questionnaires were used with information such as socioeconomic status, race/ethnicity, education level, marital status, profession, cohabitation or breeding of cats/dogs as pets, contact with the soil in gardens and unprotected plantations; consumption of beef or pig and type of water consumed. Questions were completed referring to patient records from HMM laboratory such as age, sex and address.

Blood sample were collected as part of the usual routine for evaluating the state of health of the patients and sample of the participants were subjected to serological assessment for identifying the presence of IgG anti- T. gondii. Approximately 2.5 ml of blood by venipuncture into vacutainer tube with sterile gel were collected. The serum was removed by centrifugation for analysis. Approximately 1 ml to 1.5 ml of serum was transferred to eppendorf tubes previously identified with the code assigned by the investigator during data collection, and subsequently frozen at -20^oC. This sample was maintained on average for ten days until the moment the test for determining the level of IgG anti- T. gondii was carried out in the microbiology laboratory, in the serology section of Maputo Centre Hospital.

The determination of IgG antibodies to T. gondii was performed by the serological agglutination visible method. The kit trade marked to “Atlas Medical-Toxo Latex Kit” (Lot: 81111304, William James House, Cowely Rod Cambridge, CB 4 4WX, UK), a latex agglutination test for the rapid qualitative detection and semi-quantitative serum antibodies to T. gondii was used. This commercial kit has a sensitivity of 96.1% and specificity of 89.6%. The technique of determination and interpretation of the results was performed according to the manufacturer’s instructions and recommendations.

The samples were allowed to reach room temperature prior to testing. The reagent kits anti- T. gondii were removed from the temperature change of 4°C-8°C and maintained also in a room temperature. The identification data were strictly checked prior to the execution of the test itself.

The presence of visible agglutination after the technique procedure is considered a positive result, i.e., the presence of IgG anti- T. gondii in the patient serum, equivalent to a concentration of antibodies equal or greater than 4 IU/ml, while its absence is negative result.

Tests were performed to define the presence of IgG anti- T. gondii of samples from the laboratory of Maputo Central Hospital and a private clinic in order to confirm the results and to guarantee the quality and validity of the reagents used. Ten randomized samples reagents and not reagent were tested with another kit test to determine anti- T. gondii (Armstrong) and all cases were confirmed.

Data were consolidated into a specific database and analyzed using the statistical package SPSS (Statistical Package for the Social Sciences) version 11.0. The analysis was based on descriptive statistics, with data presented into tables and graphs. The estimated prevalence of infection with T. gondii was performed with the confidence interval. For the univariate analysis, the outcome of latent infection by T. gondii was the dependent variable and the association between variables (gender, age, regular consumption of meat from cattle, breeding of cat/dog and regular contact with soil) was verified by chi-square (0.05 significance). The Fisher exact test was used for variables with expected frequency < 5. The estimates of odds ratios (OR) with 95% confidence intervals (CI) were calculated.

The study protocol was submitted to and approved by the Ethics Committee of the Institute of Health Sciences of Mozambique and the National Bioethics Committee of the Ministry of Health of Mozambique (Protocol nº TFCTBLAD036/10).

The execution of this work considered the ethical standards and all requirements of confidentiality. Participation in this study was voluntary and assured by the rendering and prior reading of the terms of consent. All study subjects signed the consent form that was encoded.

The researcher and the laboratory technicians involved in collecting blood samples ensured confidentiality both in the process of identifying samples for the study, as well as the results that were obtained later.

RESULTS

The majority of the individuals infected with HIV/AIDS were women (58.0%) aged between 31 and 40, with no evidence of regular consumption of cattle meat (76.0%), breeding cat/dog (83.0%) or regular contact with soil (73%) (Table).

The prevalence of IgG anti- T.gondii was of 46.0% (95%CI 39.2;52.9). Seropositivity was more frequent in women and in the 41 to 50 years old age group, although not statistically significant (respectively, OR = 1.30; 95%CI 0.95;1.77; p = 0.12 and OR = 2.33, 95%CI 0.84;6.44; p = 0.61). Seropositivity was higher in older age groups.

Breeding cats was the situation most significantly associated with the presence of infection (OR = 6.18; 95%CI 3.60;10.62, p < 0.000), followed by having regular contact with soil (OR = 3, 38; 95%CI 2.19;5.21, p < 0.000) and regularly consuming cattle meat (OR = 1.74; 95%CI 1.04;2.89; p = 0.05) (Table).

DISCUSSION

The estimate of 46.0% prevalence of latent infection by T. gondii in the population infected by HIV/AIDS treated at a referral center in Maputo, Mozambique, is representative of the magnitude of the problem in the country.

The relevance of this study is strengthened by the lack of studies not only in Mozambique, ¹⁹19 . Sitoe SPBL, Rafael B, Meireles LR, Andrade Jr HF, Thompson R. Preliminary report of HIV and Toxoplasma gondii occurrence in pregnant women from Mozambique. Rev Inst Med Trop Sao Paulo. 2010;52(6):291-5. DOI:10.1590/S0036-46652010000600002
https://doi.org/10.1590/S0036-4665201000... but in the African continent as a whole. ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... ^{, 3}3 . Dubey JP, Jones JL. Toxoplasma gondii infection in humans and animals in the United States. Int J Parasitol. 2008;38(11):1257-78. DOI:10.1016/j.ijpara.2008.03.007
https://doi.org/10.1016/j.ijpara.2008.03... ^{, 9}9 . Hotez PJ, Kamath A. Neglected tropical diseases in sub-saharan Africa: review of their prevalence, distribution, and disease burden. PLoS Negl Trop Dis. 2009;3(8):e412. DOI:10.1371/journal.pntd.0000412
https://doi.org/10.1371/journal.pntd.000... ^{, 20}20 . Shimelis T, Tebeje M, Tadesse E, Tegbaru B, Terefe A. Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: a comparative cross-sectional study. BMC Res Notes. 2009;2:213. DOI:10.1186/1756-0500-2-213
https://doi.org/10.1186/1756-0500-2-213... ^{, 22}22 . Uneke CJ, Duhlinska DD, Njoku MO, Ngwu BA. Seroprevalence of acquired toxoplasmosis in HIV-infected and apparently healthy individuals in Jos, Nigeria. Parassitologia . 2005;47(2):233-6. ^{, 23}23 . Zumla A, Savva D, Wheeler RB, Hira SK, Luo NP, Kaleebu P, et al. Toxoplasma serology in Zambian and Ugandan patients infected with the human immunodeficiency virus. Trans R Soc Trop Med Hyg. 1991;85(2):227-9. DOI:10.1016/0035-9203(91)90034-V
https://doi.org/10.1016/0035-9203(91)900...

The prevalence of latent infection by T. gondii found in this study was higher than most estimates in other studies conducted with HIV/AIDS positive individuals in many places around the world, particularly in neighboring countries belonging to sub-Saharan Africa. The estimates vary from 4.0% to 8.0% in Zambia, 5.0% to 17.0% in South Africa, 19.0% in Zimbabwe, 26.0% in Angola, 36.5% in Nigeria, 44.0% in Namibia, Uganda on 34.0% to 54.0%, 40.0% to 70.0% in Tanzania, 55.5% Kenya and 93.0% in Ethiopia. ¹1 . Brindle R, Holliman R, Gilks C, Waiyaki, P. Toxoplasma antibodies in HIV-positive patients from Nairobi. Trans R Soc Trop Med Hyg. 1991;85(6):750-1. DOI:10.1016/0035-9203(91)90443-3
https://doi.org/10.1016/0035-9203(91)904... ^{, 5}5 . Gille E, Björkman A, Rooth I, Ljungström I, Linder E. Low seroprevalence of Toxoplasma gondii antibodies in a Tanzanian village. Trans R Soc Trop Med Hyg. 1992;86(3):263-5. DOI:10.1016/0035-9203(92)90303-T
https://doi.org/10.1016/0035-9203(92)903... ^{, 7}7 . Hari KR, Modi MR, Mochan AH, Modi G. Reduced risk of toxoplasma encephalitis in HIV-infected patients-a prospective study from Gauteng, South Africa. Int J STD AIDS. 2007;18(8):555-8. DOI:10.1258/095646207781439829
https://doi.org/10.1258/0956462077814398... ^{, 10}10 . Lindström I, Kaddu-Mulindwa DH, Kironde F, Lindh J. Prevalence of latent and reactivated Toxoplasma gondii parasites in HIV-patients from Uganda. Acta Trop. 2006;100(3):218-22. DOI:10.1016/j.actatropica.2006.11.002
https://doi.org/10.1016/j.actatropica.20... ^{, 20}20 . Shimelis T, Tebeje M, Tadesse E, Tegbaru B, Terefe A. Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: a comparative cross-sectional study. BMC Res Notes. 2009;2:213. DOI:10.1186/1756-0500-2-213
https://doi.org/10.1186/1756-0500-2-213...

21 . Tenter AM, Heckeroth AR, Weiss LM. Toxoplasma gondii: from animals to humans. Int J Parasitol. 2000;30(12-13):1217-58. DOI:10.1016/S0020-7519(00)00124-7
https://doi.org/10.1016/S0020-7519(00)00...

22 . Uneke CJ, Duhlinska DD, Njoku MO, Ngwu BA. Seroprevalence of acquired toxoplasmosis in HIV-infected and apparently healthy individuals in Jos, Nigeria. Parassitologia . 2005;47(2):233-6. ^{- 23}23 . Zumla A, Savva D, Wheeler RB, Hira SK, Luo NP, Kaleebu P, et al. Toxoplasma serology in Zambian and Ugandan patients infected with the human immunodeficiency virus. Trans R Soc Trop Med Hyg. 1991;85(2):227-9. DOI:10.1016/0035-9203(91)90034-V
https://doi.org/10.1016/0035-9203(91)900... In some countries in sub-Saharan Africa, particularly Mozambique, where the prevalence of HIV/AIDS is elevated, epidemiological information on toxoplasmosis in the whole population is limited because of the difficulties in carrying out laboratory investigations in network health services. ²⁴24 . Wallace, GD, Marshall, L, Marshall, M. Cats, rats, and toxoplasmosis on a small Pacific island. Am J Epidemiol. 1972;95(5):475-82.

A recent study evaluating the presence of active/recent infection by IgM anti- T. gondii revealed a prevalence of 31.3% in HIV pregnant patients at the Maputo Central Hospital. ¹⁹19 . Sitoe SPBL, Rafael B, Meireles LR, Andrade Jr HF, Thompson R. Preliminary report of HIV and Toxoplasma gondii occurrence in pregnant women from Mozambique. Rev Inst Med Trop Sao Paulo. 2010;52(6):291-5. DOI:10.1590/S0036-46652010000600002
https://doi.org/10.1590/S0036-4665201000... This gives additional information to the results of this study about the load associated with toxoplasmosis in Mozambique.

Prevalence rates increase with age, ¹³13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 18}18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... ^{, 20}20 . Shimelis T, Tebeje M, Tadesse E, Tegbaru B, Terefe A. Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: a comparative cross-sectional study. BMC Res Notes. 2009;2:213. DOI:10.1186/1756-0500-2-213
https://doi.org/10.1186/1756-0500-2-213... consistent with the more frequent finding in this study being in the 41 to 50 age group, where 51.8% of the 54 cases belonging to this group were reactive.

Despite the increased participation of women in this study and higher seropositivity in this population, there were no differences in relation to gender. Among the 116 women’s samples tested, 29.5% were positive. This can probably be explained by the significant prevalence of HIV infection in this population and higher levels of seeking medical care in our reality. ⁶6 . González R, Munguambe K, Aponte J, Bavo C, Nhalungo D, Macete E, et al. High HIV prevalence in a southern semi-rural area of Mozambique: a community-based survey. HIV Med. 2012;13(10):581-8. DOI:10.1111/j.1468-1293.2012.01018.x
https://doi.org/10.1111/j.1468-1293.2012... ^{, 12}12 . Maueia C, Costa D, Meggi B, Ismael N, Walle C, Curvo R, et al. Frequency of human immunodeficiency virus type-2 in hiv infected patients in Maputo City, Mozambique. Virol J. 2011;8(1):408. DOI:10.1186/1743-422X-8-408
https://doi.org/10.1186/1743-422X-8-408... ^{, 16}16 . Perez-Hoyos S, Naniche D, Macete E, Aponte J, Sacarlal J, Sigauque B, et al. Stabilization of HIV incidence in women of reproductive age in Southern Mozambique. HIV Med. 2011;12(8):500-5. DOI:10.1111/j.1468-1293.2010.00908.x
https://doi.org/10.1111/j.1468-1293.2010... This extends the vulnerability in this population, including the increased risk of vertical transmission not only of HIV, but also of T. gondii. ⁴4 . Falusi O, French AL, Seaberg EC, Tien PC, Watts DH, Minkoff H, et al. Prevalence and predictors of Toxoplasma seropositivity in women with and at risk for human immunodeficiency virus infection. Clin Infect Dis. 2002;35(11):1414-7. DOI:10.1086/344462
https://doi.org/10.1086/344462... ^{, 15}15 . Pappas G, Roussos N, Falagas ME. Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis. Int J Parasitol. 2009;39(12):1385-94. DOI:10.1016/j.ijpara.2009.04.003
https://doi.org/10.1016/j.ijpara.2009.04...

Risk factors in this population reflect the data in the literature and the social, economic and cultural context of Mozambique. ¹⁹19 . Sitoe SPBL, Rafael B, Meireles LR, Andrade Jr HF, Thompson R. Preliminary report of HIV and Toxoplasma gondii occurrence in pregnant women from Mozambique. Rev Inst Med Trop Sao Paulo. 2010;52(6):291-5. DOI:10.1590/S0036-46652010000600002
https://doi.org/10.1590/S0036-4665201000... Prevalence estimates of latent infections by T. gondii in HIV-infected patients showed a wide variation in the risk factors and ethnicity factors including classic factors such as those evaluated in this study, in terms of exposure to soil, animals and meat intake. ⁸8 . Hill D, Dubey JP. Toxoplasma gondii: transmission, diagnosis and prevention. Clin Microbiol Infect. 2002;8(10):634-40. DOI:10.1046/j.1469-0691.2002.00485.x
https://doi.org/10.1046/j.1469-0691.2002... ^{, 11}11 . Marques JM, da Silva DV, Correia NAB, Velásquez G, da Silva RC, Langoni H, et al. Prevalence and risk factors for human toxoplasmosis in a rural community. J Venom Anim Toxins Incl Trop Dis. 2008;14(4):673-84. DOI:10.1590/S1678-91992008000400010
https://doi.org/10.1590/S1678-9199200800... ^{, 13}13 . Montoya JG, Hesenfeld O. Toxoplasmosis. Lancet . 2004;363(9425):1965-76. DOI:10.1016/S0140-6736(04)16412-X
https://doi.org/10.1016/S0140-6736(04)16... ^{, 14}14 . Nissapatorn V. Toxoplasmosis in HIV/AIDS: a living legacy. Southeast Asian J Trop Med Public Health. 2009;40(6):1158-78. ^{, 18}18 . Robert-Gangneux F, Dardé ML. Epidemiology of and diagnostic strategies for toxoplasmosis. Clin Microbiol Rev. 2012;25(2):264-96. DOI:10.1128/CMR.05013-11
https://doi.org/10.1128/CMR.05013-11... ^{, 20}20 . Shimelis T, Tebeje M, Tadesse E, Tegbaru B, Terefe A. Sero-prevalence of latent Toxoplasma gondii infection among HIV-infected and HIV-uninfected people in Addis Ababa, Ethiopia: a comparative cross-sectional study. BMC Res Notes. 2009;2:213. DOI:10.1186/1756-0500-2-213
https://doi.org/10.1186/1756-0500-2-213... ^{, 22}22 . Uneke CJ, Duhlinska DD, Njoku MO, Ngwu BA. Seroprevalence of acquired toxoplasmosis in HIV-infected and apparently healthy individuals in Jos, Nigeria. Parassitologia . 2005;47(2):233-6. Findings of non-reactive tests for toxoplasmosis in studies addressing geographic regions where there are no cats, such as the Pacific Islands ²⁵25 . World Health Organization. Antiretroviral Therapy for HIV Infection in Adults and Adolescents: Recommendations for a public health approach 2010 revision. Geneva; 2010. are registered.

Throughout the history of the epidemic of HIV infection, toxoplasmosis has been one of the most significantly opportunistic infections detected in patients with AIDS. ⁴4 . Falusi O, French AL, Seaberg EC, Tien PC, Watts DH, Minkoff H, et al. Prevalence and predictors of Toxoplasma seropositivity in women with and at risk for human immunodeficiency virus infection. Clin Infect Dis. 2002;35(11):1414-7. DOI:10.1086/344462
https://doi.org/10.1086/344462... Even in the era after the introduction of HAART, it still represents important public health problem, especially to vulnerable populations in developing and developed countries. ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600...

This study has important implications, considering the possibility of reducing morbidity and mortality and increased survival in patients infected with HIV/AIDS with the adoption and development of HAART, both in adults and in children. ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... ^{, 17}17 . Ramos Jr AN, Matida LH, Hearst NG, Heukelbach J. Opportunistic illnesses in Brazilian children with AIDS: results from two national cohort studies. AIDS Res Ther. 2011;8:23. DOI:10.1186/1742-6405-8-23
https://doi.org/10.1186/1742-6405-8-23... Different studies indicate changing clinical and epidemiological patterns related to neurotoxoplamosis ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... ^{, 7}7 . Hari KR, Modi MR, Mochan AH, Modi G. Reduced risk of toxoplasma encephalitis in HIV-infected patients-a prospective study from Gauteng, South Africa. Int J STD AIDS. 2007;18(8):555-8. DOI:10.1258/095646207781439829
https://doi.org/10.1258/0956462077814398... ^{, 17}17 . Ramos Jr AN, Matida LH, Hearst NG, Heukelbach J. Opportunistic illnesses in Brazilian children with AIDS: results from two national cohort studies. AIDS Res Ther. 2011;8:23. DOI:10.1186/1742-6405-8-23
https://doi.org/10.1186/1742-6405-8-23... and its association with immune reconstitution inflammatory syndrome (IRIS). ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... ^{, 15}15 . Pappas G, Roussos N, Falagas ME. Toxoplasmosis snapshots: global status of Toxoplasma gondii seroprevalence and implications for pregnancy and congenital toxoplasmosis. Int J Parasitol. 2009;39(12):1385-94. DOI:10.1016/j.ijpara.2009.04.003
https://doi.org/10.1016/j.ijpara.2009.04... Together, these findings extend the importance of adopting screening routines for T. gondii infection in all newly diagnosed cases of HIV infection, with follow-up serologic depending on the context of risk associated with each individual.

Limitations of this study include the sampling process, that may have undersized the real prevalence by tackling patients who have been followed in this reference unit in the country. Population which are highly vulnerable to both toxoplasmosis and HIV may not have been included in the analysis. Even with these restrictions, the prevalence is high and significant enough to indicate the magnitude of the problem.

The use of single test for assessment of IgG antibodies was unable to distinguish accurately from recent to chronic or reactivated infections in the studied population. It is appropriate to remark on the vulnerability of the health public services in Mozambique by finding no wide availability of specific reagents to detain anti- T.gondii in public clinical laboratories. This was made possible by this research, which reaffirms to the health authorities the social and economic relevance of investments in this sector.

It reinforces the positive impact of prophylaxis ²2 . De Oliveira JF, Greco DB, Oliveira GC, Christo PP, Crosland Guimarães MD, Oliveira RC. Neurological disease in HIV-infected patients in the era of highly active antiretroviral treatment: a Brazilian experience. Rev Soc Bras Med Trop. 2006;39(2):146-51. DOI:10.1590/S0037-86822006000200002
https://doi.org/10.1590/S0037-8682200600... to be established in HIV-infected individuals in Mozambique with advanced degree of immunodeficiency, given the high rates of morbidity and mortality associated. The importance of these findings is even greater in a country with high prevalence and incidence of HIV infection and patterns of high endemicity for Toxoplasmosis,

It emphasizes the magnitude of toxoplasmosis in the HIV-infected population in Mozambique and the urgent need for additional clinical and epidemiological research. The prioritization of research and development to address the complex dynamics of transmission of toxoplasmosis and its impacts is urgent in Africa. Similarly, extending the programs oriented towards this population for the serological diagnosis and prevention of toxoplasmosis, including pregnant women, aiming to reduce the burden of morbidity and mortality associated with new infections in Mozambique should also be prioritized.

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