Preliminary report of HIV and Toxoplasma gondii occurrence in pregnant women from Mozambique

Abstract

Toxoplasmosis, a protozoan disease, causes severe disease in fetuses during pregnancy and deadly encephalitis in HIV patients. There are several studies on its seroprevalence around the world, but studies focusing on African countries are limited in number and mostly anecdotal. We studied two groups of samples from Mozambique by ELISA, using serum samples from 150 pregnant women and six Cerebrospinal fluid (CSF) samples from AIDS patients with encephalitis. HIV status was confirmed, and CD4 blood counts were obtained from HIV-positive pregnant women. IgG seroprevalence of the group as a whole was 18.7% (28/150), with a higher prevalence in HIV-positive individuals compared to those who were HIV-negative (31.3%, [18/58] vs. 10.9%, [10/92]) patients. These data may be biased due to cumulative effects of exposition affecting disease prevalence. If corrected, this data may indicate an interaction of HIV and T. gondii. Prevalence of both diseases increases with age, but this is more clearly seen for toxoplasmosis (p < 0.005) than HIV infection, possibly explained by higher transmission of HIV after childhood. In HIV patients suffering from encephalitis, CSF serology showed that 33% of specific IgG CSF had a high avidity, which was in accordance with the data from the group of pregnant women. Lower prevalence rates of both infections in older groups could be explained by more deaths in the infected groups, resulting in an artificially lower prevalence. Using CD4 counts as a marker of time of HIV infection, and correcting for age, patients with contact with T. gondii had fewer CD4 cells, suggesting prolonged HIV disease or other causes. Toxoplasma IgG prevalence is higher in HIV+ groups, which could be ascribed to HIV- and T. gondii-associated risk factors, such as exposure to higher and more diverse social contacts. The low incidence of Toxoplasma IgG in younger age groups shows that transmission could be related to better access to cyst-containing meat in adulthood, as environmental transmission due to oocysts is usually blamed for higher incidence in children. Taken together, these data support the urgent need of research in toxoplasmosis in Africa, especially in the presence of HIV epidemics.

Portugal and Angola: similarities and differences inToxoplasma gondiiseroprevalence and risk factors in pregnant women

“…With the exception of the Republic of Congo [2], which is a neighbour of Angola to the north, no data on T. gondii seroprevalence in these particular female populations were available from other countries neighbouring Angola. The prevalence of antibodies to T. gondii in pregnant women from Luanda region found in this study (27%) is lower than most of those reported from Western African countries, with the exception of the rate found in Burkina Faso (25·3% and 34·7%) [3,19], and is nearer to the prevalence found in East African coast countries, Sudan (34·1%) [20] and Mozambique (18·7%) [21], which is also another country with influence of Portuguese culture and dietary habits. It is also quite similar to the prevalence found in some European countries such as Portugal (21·9%, this study), Spain (21%) [3], Italy (22·7%) [3], Greece (20·1%) [3], Slovakia (22·1%) [3] or Ireland (24·6%) [3].…”

Seroprevalence of Toxoplasma gondii IgG antibody in HIV/AIDS-infected individuals in Maputo, Mozambique

“…24 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. 19 This gives additional information to the results of this study about the load associated with toxoplasmosis in Mozambique.…”

“…The relevance of this study is strengthened by the lack of studies not only in Mozambique, 19 but in the African continent as a whole. 2,3,9,20,22,23 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.…”

“…7,9,10,20 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. 19 The paucity of reliable information on risk factors, main means of transmission and of preventative measures used, is of concern not only for researchers, 9,18,22 but for society in general. Considering the scale of AIDS in Mozambique 6,12,16 and the vulnerability of HIV-infected people with toxoplasmosis, there is a clear need for further studies on this subject.…”

Nephrotic syndrome associated with toxoplasmosis: report of seven cases

“…Recent seroepidemiological surveys performed in different segments of the Brazilian population revealed infection rates ranging from 32.4 to 74.5%, depending on the age, with highest values occurring in adults 3,16,17,18 . In other countries high rates of human infection with T. gondii can also be found 1,6,8,11,15 .…”