320 likes | 336 Views
Schistosoma mansoni and HIV-1 infection: Is there any association?. Humphrey D. Mazigo, PhD. Global adult prevalence of HIV and schistosomiasis (Bastinduy et al., 2014). INTRODUCTION.
E N D
Schistosoma mansoni and HIV-1 infection: Is there any association? Humphrey D. Mazigo, PhD
Global adult prevalence of HIV and schistosomiasis (Bastinduy et al., 2014)
INTRODUCTION Globally, 35.3M (≥15 years) are infected with HIV-1 infection, of these, 23.5M (68%) live in SSA (UNAIDS.,2013) Globally, 779M in 76 countries are at risk for schistosomiasis and 207M are infected, 90% live in sub-Saharan Africa (Steinmann et al.,2006; Hotez et al., 2007)
Global burden of diseases The DALYs lost due to schistosomiasis are estimated at 4.5M The DALYs lost due to HIV infection is >80M Combined DALYs results into significant morbidities and mortalities Hotez et al.,2006; 2014
Schistosomiasis in Tanzania Two spp S. mansoni and S. haematobium are endemic and widely spread in country S. mansoni is wide spread along the large water bodies S. haematobium is mainly in small water bodies National prevalence: 52% but varies between regions Health effect of S. mansoni infection: Peri-portal fibrosis, hepatomegaly, splenomegaly and hepatosplenomegaly and death associatted with portal hypertension, oesophagealvarices and hemetemesis Mazigo et al., 2012; Rollinson et al., 2012
HIV-1 in Tanzania National prevalence is 5.2% and varies between regions Age: 15 – 49 yrs – 5% Sex: Female 6% and males 4% Residential: Urban 7% vs rural 4% Fishing villages along the Lake Victoria shores marked as highly risk groups THMIS: 2013/14
HIV-1 and S. mansoni co-infections Because of the overlap of HIV-1 and S. mansoni in SSA, half of 25M HIV infected individuals may be co-infected (Secor 2000: Bentwich et al., 2000) Hypothesis:- co-infection of HIV-1 and S. mansoni may enhance virulence of each other within a co-infected host (Lawn 2001; Wolday 2002) But, the role played by concurrent HIV-1 infection as accelerating factor for S. mansoni infection, related morbidities and PZQ treatment outcome remain a topic of further studies
HIV-1 and S. mansoni co-infections The effects of HIV-1 on schistosomiasis CD4+ T cell reductions by HIV-1:- - Alters eggs excretion efficiency (Karanjaet al., 1997) - Decrease fibrogenesis, hence, severe hepatic morbidities (Mwinziet al., 2001) - Increases susceptible to re-infection with Schistosomes (Karanja et al., 2002) - Low CD4+ T cell counts are associated with reduced levels of eosinophils which are necessary for resistance to repeated schistosomalinfections (Ganleyet al., 2006)
HIV-1 and S. mansoni co-infections The effects of schistosomiasis in HIV-1 Infections with schistosomes cause chronic stimulation of the immune system with a strong bias towards Th2 CD4+ response (Pearce et al., 1991). Th2 response to Schistosomes Ag down-regulates Th1-type responses which are necessary for efficient antiviral CD8+ CTL prod.(McElroy et al., 2005). HIV replicates more rapidly in activated T cells with Schistosomes Ag and CD4+ T cells lines are more easily affected than Th1 (Lawn et al., 1991). In Ethiopia, a study of HIV-1 infected and uninfected, helminth infection was associated with increased T- cell activation (Kassu, 2003). In HIV-uninfected indiv. increased T-cell activation make them more susceptible to HIV infection (Kassu, 2003).
Is S. mansoni associatted with HIV-1 infection Odd of developing immunological failure were 4 times greater in patients with SM/HIV-1 co-infection
Factors associated with intensities of S. mansoni infection Intensity of S. mansoni infection was not associated with HIV-1 infection (AOR = 0.84,95% CI; 0.56 – 1.25) The intensity of S.mansoni infection was associated with :- Male gender (AOR = 1.65,95% CI; 1.32-2.08, P<0.0001) Young ages (21–30yrs; AOR = 1.68,95% CI; 1.14-2.48,P<0.01) Involvement in fishing activities (AOR = 1.62,95%CI; 1.10-2.41, P<0.01) Being illiterate (AOR = 1.33,95% CI;1.07 – 1.66, P<0.014) Living in the study villages. - Igalagala – (AOR=1.71,95%CI;1.23-2.40) - Kayenze – (AOR=1.62,95%CI;1.23-2.13) - Sangabuye – (AOR=1.38,95%CI;1.001-1.89)
Prevalence of PPF The overall prevalence PPF (grades C-F) was 14.78%: - 29.55% were grade C, 52.63% (130/247) D,14.17% (35/247) E and 3.64% (9/247) were grade F In relation to S. mansoni infection, of the individuals detected with PPF, 52.23% (129/247) had detectable eggs PPF prevalence did not differ by prevalence (P=0.10) and infection intensities of S. mansoni based on egg count (epg) (P=0.11)
Results In relation to HIV-1 infection, 13.79% and 15.01% of the HIV-1 infected and uninfected individuals had PPF (P=0.72) HIV-1 infected: n=4 had grade C, n = 8 had grade D and n = 4 had grade E-F Factors associated with PPF:- Male gender (AOR = 2.27, P< 0.001), Age group 21–30 years (AOR = 2.45, P< 0.028) Residential time, 11–20 years (AOR = 3.52,P< 0.01) and ≥21yrs (AOR =2.66,P< 0.01)
In relation to HIV-1 Comparison of the height adjusted mean deviations of organs in relation to infection with S. mansoni and HIV-1 infection status
Correlation between left liver lobe sizes and CD4+ in co-infected individuals The no correlation was observed (r=-0.16, P=0.084)
Predictors of left liver lobe hepatomegaly, splenomegaly and hepatosplenomegaly Left liver lobe measurements:- the age of the study participants (P<0.038), malaria infection (P<0.038) and intensities of S. mansoni infection (P<0.01). HIV-1 infection was not (P=0.069) Spleen measurements:- being male (P<0.002), fishing occupation (P<0.05), village of residence (living in Kayenze village, P<0.039 and Igalagala village, P<0.005), being infected with malaria parasite (P<0.018) and HIV-1 infection (P<0.05) Hepatosplenomegaly:- village of residence (living at Sangabuye village, AOR=2.09, P<0.022, Kayenze village, AOR=1.83, P<0.04: Igalagala, AOR=2.49, P<0.023) and being heavily infected with S. mansoni infection (AOR=1.13, 95%CI; P<0.041)
Parasitological cure rates in relation to HIV-1 serostatus Overall parasitological cure rate: 61.80% (n=343/555) HIV-1 negative: 526 infected with S. mansoni at baseline, cure rate: 62.19% (329/555) HIV-1 + S. mansoni:- cure rate: 48.28% (14/29) No significance difference (P= 0.12)
Parasitological cure rates in relation to CD4+ cells counts Co-infected with CD4+ cell counts <350cells/µL: cure rate 43.75%(7/16) Co-infected with CD4+ cells counts ≥ 350cells/µL: cure rate: 66.67%(8/12).
Comparison of HIV-1 viral loads, CD4-Th2-lymphocytes and effects of praziquantel treatment among adults infected or not with S. mansoni in fishing villages of North-Western Tanzania. Infectious Diseases of Poverty
Conclusion S. mansoni-related PPF, liver and spleen enlargements occur in the study population and with similar grades observed among co-infected and in S. mansoni only infected individuals HIV-1 infection or CD4+ levels was not associated with increased risk of heavy intensity of S. mansoni infection or severe organomegally and had no effect on PZQ treatment outcomes PZQ treatment had a significant effect on prevalence, intensity of infection and S. mansoni related morbidities but did not lead to any changes on CD4+ cell counts and plasma viral loads No association between S. mansoni and HIV-1 infection. Further study are needed