Coinfection with Schistosoma haematobium and Plasmodium falciparum and Anaemia Severity among Pregnant Women in Munyenge, Mount Cameroon Area: A Cross-Sectional Study

Prevalence and associated factors of schistosomiasis among pregnant women in northern Senegal

BACKGROUND

Schistosomiasis remains a public health concern worldwide. It is responsible for more than 240 million cases in 78 countries, 40 million of whom are women of childbearing age. In the Senegal River basin, both Schistosoma haematobium and Schistosoma mansoni are very prevalent in school-age children. However, there is a lack of information on the burden of schistosomiasis in pregnant women, which can cause complications in the pregnancy outcome. This study aimed to determine the prevalence and associated factors of schistosomiasis in pregnant women.

METHODS

We conducted a prospective cross-sectional study of pregnant women attending antenatal clinics at the health center of the Senegalese Sugar Company and at the hospital of Richard Toll between August and December 2021. The urine and stool samples collected were examined using microscopy techniques and quantitative polymerase chain reaction (qPCR) to detect the presence of S. haematobium and S. mansoni. The urines were previously tested using urine reagent strips to detect hematuria and proteinuria. Socio-demographical, clinical, and diagnostically data were recorded by the midwife and the gynaecologist. The data were analyzed using a logistic regression model.

RESULTS

Among the 298 women examined for the infection by microscopic, 65 (21.81%) were infected with urogenital schistosomiasis, 10 (3.36%) with intestinal schistosomiasis, and 4 (1.34%) were co-infected with both types of schistosomiasis. Out of the 288 samples tested by qPCR, 146 (48.99%) were positive for S. haematobium, 49 (35.51%) for S. mansoni and 22 (15.94%) for both species (co-infection). Pregnant women having microscopic haematuria and proteinuria were significantly more infected (p < 0.05).

CONCLUSION

This study has revealed a high prevalence of schistosomiasis in pregnant women in Senegal. The qPCR allowed us to detect more cases compared to the microscopy. There is a need to conduct more studies to understand the real burden of the disease and to set up a surveillance system to prevent pregnancy-related complications.

Beyond schistosomiasis: unraveling co-infections and altered immunity

Schistosomiasis is a neglected tropical disease caused by the helminth Schistosoma spp. and has the second highest global impact of all parasites. Schistosoma are transmitted through contact with contaminated fresh water predominantly in Africa, Asia, the Middle East, and South America. Due to the widespread prevalence of Schistosoma, co-infection with other infectious agents is common but often poorly described. Herein, we review recent literature describing the impact of Schistosoma co-infection between species and Schistosoma co-infection with blood-borne protozoa, soil-transmitted helminths, various intestinal protozoa, Mycobacterium, Salmonella, various urinary tract infection-causing agents, and viral pathogens. In each case, disease severity and, of particular interest, the immune landscape, are altered as a consequence of co-infection. Understanding the impact of schistosomiasis co-infections will be important when considering treatment strategies and vaccine development moving forward.

The Global Prevalence of Schistosoma mansoni, S. japonicum, and S. haematobium in Pregnant Women: A Systematic Review and Meta-Analysis

Schistosomiasis is a neglected tropical disease affecting 40 million women of childbearing age worldwide. Its global disease prevalence among pregnant women is still unknown. This meta-analysis determined the pooled prevalence of schistosomiasis among pregnant women globally. Additionally, this study also determined the pooled prevalence based on infection intensity based on eggs per gram. Observational studies on the prevalence of schistosomiasis among pregnant patients were obtained from Medline, Scopus, and CINAHL from January 2001 until August 2020. A review of titles and abstracts was done independently by six reviewers. The quality of the included studies was assessed using the Newcastle-Ottawa Scale for case-control, cohort, and cross-sectional studies. A total of 27 studies were included in the meta-analysis and meta-regression. The pooled prevalence of S. haematobium was 13.44 (CI: 8.90-19.80) per 100 observations, while the pooled prevalence of S. mansoni was 12.18 (CI: 4.47-29.12) per 100 observations. The prevalence of S. japonicum infection in one study was 53.54 (CI: 43.23-63.62) per 100 observations. Our results showed a prevailing health problem of schistosomiasis during pregnancy in various countries worldwide. This strengthens the need to conduct more schistosomiasis research, prevention, and control programs in pregnant women.

Malaria and Helminthic Co-Infection during Pregnancy in Sub-Saharan Africa: A Systematic Review and Meta-Analysis

Malaria and helminthic co-infection during pregnancy causes fetomaternal haemorrhage and foetal growth retardation. This study determined the pooled burden of pregnancy malaria and helminthic co-infection in sub-Saharan Africa. CINAHL, EMBASE, Google Scholar, Scopus, PubMed, and Web of Science databases were used to retrieve data from the literature, without restricting language and publication year. The Joanna Briggs Institute’s critical appraisal tool for prevalence studies was used for quality assessment. STATA Version 14.0 was used to conduct the meta-analysis. The I² statistics and Egger’s test were used to test heterogeneity and publication bias. The random-effects model was used to estimate the pooled prevalence at a 95% confidence interval (CI). The review protocol has been registered in PROSPERO, with the number CRD42019144812. In total, 24 studies (n = 14,087 participants) were identified in this study. The pooled analysis revealed that 20% of pregnant women were co-infected by malaria and helminths in sub-Saharan Africa. The pooled prevalence of malaria and helminths were 33% and 35%, respectively. The most prevalent helminths were Hookworm (48%), Ascaris lumbricoides (37%), and Trichuris trichiura (15%). Significantly higher malaria and helminthic co-infection during pregnancy were observed. Health systems in sub-Saharan Africa must implement home-grown innovative solutions to underpin context-specific policies for the early initiation of effective intermittent preventive therapy.

Immunomodulatory Potential of Non-Classical HLA-G in Infections including COVID-19 and Parasitic Diseases

Human Leukocyte Antigen-G (HLA-G), a polymorphic non-classical HLA (HLA-Ib) with immune-regulatory properties in cancers and infectious diseases, presents both membrane-bound and soluble (sHLA-G) isoforms. Polymorphism has implications in host responses to pathogen infections and in pathogenesis. Differential expression patterns of HLA-G/sHLA-G or its polymorphism seem to be related to different pathological conditions, potentially acting as a disease progression biomarker. Pathogen antigens might be involved in the regulation of both membrane-bound and sHLA-G levels and impact immune responses during co-infections. The upregulation of HLA-G in viral and bacterial infections induce tolerance to infection. Recently, sHLA-G was found useful to identify the prognosis of Coronavirus disease 2019 (COVID-19) among patients and it was observed that the high levels of sHLA-G are associated with worse prognosis. The use of pathogens, such as Plasmodium falciparum, as immune modulators for other infections could be extended for the modulation of membrane-bound HLA-G in COVID-19-infected tissues. Overall, such information might open new avenues concerning the effect of some pathogens such as parasites in decreasing the expression level of HLA-G to restrict pathogenesis in some infections or to influence the immune responses after vaccination among others.

Prevalence of urinary schistosomiasis in women: a systematic review and meta-analysis of recently published literature (2016-2020)

BACKGROUND

Urinary schistosomiasis is a serious threat in endemic territories of Africa and the Middle East. The status of female urinary schistosomiasis (FUS) in published literature between 2016 and 2020 was investigated.

METHODS

A systematic search in PubMed, Scopus, Google Scholar, and Web of Science, based on the 'Preferred Reporting Items for Systematic Reviews and Meta-analyses' checklist, and a meta-analysis using random-effects model to calculate the weighted estimates and 95% confidence intervals (95% CIs) were done.

RESULTS

Totally, 113 datasets reported data on 40,531 women from 21 African countries, showing a pooled prevalence of 17.5% (95% CI: 14.8-20.5%). Most studies (73) were performed in Nigeria, while highest prevalence was detected in Mozambique 58% (95% CI: 56.9-59.1%) (one study). By sample type and symptoms, vaginal lavage [25.0% (95% CI: 11.4-46.1%)] and hematuria 19.4% (95% CI: 12.2-29.4%) showed higher FUS frequency. Studies using direct microscopy diagnosed a 17.1% (95% CI: 14.5-20.1%) prevalence rate, higher than PCR-based studies 15.3% (95% CI: 6.1-33.2%). Except for sample type, all other variables had significant association with the overall prevalence of FUS.

CONCLUSIONS

More studies are needed to evaluate the true epidemiology of FUS throughout endemic regions.

Impact of helminthiasis on gestational anemia in low- and middle-income countries: a systematic review and meta-analysis of more than 19,000 women

Intestinal helminthiasis are a common public health problem in developed and developing countries. It is thought that they can influence pregnancy by causing gestational anemia. The aim of this study was to determine if there is a relationship between helminth infection and gestational anemia. A structured review of scientific literature was conducted through active search in the electronic databases MEDLINE^® and LILACS^® until December 2021, following 2020 PRISMA statement. The studies were reviewed independently by two authors, extracting the most relevant information from each study. Cross-sectional studies, case-control and ecological studies were included, with no date or language limit. Randomized clinical trials were excluded. A total of 38 studies were included in the systematic review. The study populations of all studies belonged to low- and middle-income countries: 28 studies from Africa, 6 from Asia, 3 from Latin America and 1 from Oceania. Overall, the average prevalence of gestational anemia among the included studies was 40% (95% CI 34-46%). Hookworm was the predominant species detected in most studies (19/38; 50%), followed by Ascaris lumbricoides (15/38; 39.5%). Gestational anemia was positively associated with A. lumbricoides (OR 1.86, 95% CI 1.12-3.08) and hookworms (OR 3.09, 95% CI 1.99-4.78). Prevalence of malaria was not associated with the magnitude of the effect of hookworm on anemia risk during meta-regression (p=0.5182). The results of this review indicate that there is a statistically significant association between helminthiasis and gestational anemia. Although hookworm is the main species associated with the outcome, prevalence of malaria was not associated with the magnitude of the effect of hookworm on anemia risk. The impact of other species needs to be defined given the expected bias that arises from polyparasitism when defining comparison groups.

Prevalence and determinants of Anemia among pregnant women in sub-Saharan Africa: a systematic review and Meta-analysis

BACKGROUND

Anemia is one of the world's leading cause of disability and the most serious global public health issues. This systematic review and meta-analysis was carried out very prudently in order to give up the pooled prevalence and determinants of anemia in Sub-Saharan Africa.

METHODOLOGY

To carry out this ephemeral systematic review and meta-analysis, a correlated literature review was done from various sources, PubMed Medline and Google Scholar Journals. Anemia related searching engine was used to make the study more evocative and intensive. We used modified Newcastle-Ottawa quality assessment scale for cross sectional studies to evaluate the quality of the study in relations of their inclusion. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was tracked to conduct this study. The pooled effect size was computed using the review manager and Compressive Meta-analysis software.

RESULTS

Twenty-fife studies, which encompassed 15,061 pregnant women, were chosen for the analysis. From those an overall prevalence of anemia in pregnancy in SSA was 35.6%. However, the result from meta-analysis showed that women who were infected with intestinal parasite were 3.59 times more likely to develop anemia compared to those who were not infected [OR:3.59, 95% CI (2.44,5.28)].The result showed that women who had no iron and folic-acid supplementation were 1.82 times more likely to develop anemia compared to those women who had iron and folic-acid supplementation {OR:1.82, 95% CI (1.22,2.70]. Women who had women were in third trimester pregnancy were 2.37 times more likely to develop anemia compared to those who were in first and second trimester [OR:2.37, 95% CI (1.78, 3.24)]. Women who had low dietary diversity score were 3.59 times more likely to develop anemia compared to those who had high dietary diversity score [OR: 3.59, 95% CI (2.44, 5.28].

CONCLUSIONS

Our finding from this systematic review and meta-analysis displays the high case in prevalence of anemia among pregnant women in Sub-Saharan Africa. Predictors for this includes: intestinal parasite, iron and folic-acid supplementation, third trimester pregnancy and dietary diversified intake score were statistically correlated positively with anemia in pregnancy. These need cautious evaluation of impact of prevention effort for operational policy, programs and design nutrition intrusions for refining maternal food consumption during pregnancy. Also, dietary education intrusion requires to be prearranged to satisfy the desires of pregnant women. The finding of this work will be used as an evidences for policy makers of Africa; entirely for maternal and child health care. Lastly, we suggested further investigations to be carried out in the area of the study for more rigorous and comprehensive recommendations.

Confounding influences of malnutrition and Plasmodium falciparum and Schistosoma haematobium infections on haematological parameters in school children in Muyuka, Cameroon

Background

School-aged children (SAC) are a high-risk demographic group for infectious diseases and malnutrition. The objective of this study was to assess the burden and the effect of Plasmodium falciparum and Schistosoma haematobium infections on the haematological indices in SAC and the confounding influence of malnutrition on the outcomes.

Methods

This cross-sectional study was conducted in SAC 4–14 years old living in Ikata, Bafia and Mile 14-Likoko in Muyuka, Cameroon. Anthropometric measures of malnutrition were obtained and blood samples collected were used for detection of malaria parasites by Giemsa-stained blood films using light microscopy and complete blood count analysis using an automated haematology analyser. Urine samples collected were used to detect micro haematuria with the aid of reagent strips and the eggs of S. haematobium by urine filtration technique. Multiple linear regression model was used to examine influence of independent variables on haematological parameters.

Results

Out of the 606 SAC examined, the prevalence of single infections with Plasmodium or S. haematobium and co-infection with both parasites was 16.2, 16.3 and 8.3%, respectively. Overall, malaria parasite (MP), urogenital schistosomiasis, malnutrition, anaemia, haematuria, microcytosis and thrombocytopenia was prevalent in 24.4, 24.6, 25.9, 74.4, 12.2, 45.4 and 11.1% of SAC, respectively. A significant linear decline (P = 0.023) in prevalence of P. falciparum infection with the severity of stunting was observed. Factors that significantly influenced haematological parameters included haemoglobin: age, stunting and MP; haematocrit: age and MP; white blood cell count: age; red blood cell count; age and MP; lymphocyte counts: stunting; mean cell volume: age; mean cell haemoglobin: age and stunting; mean cell haemoglobin concentration: sex, stunting and red cell distribution width-coefficient of variation: sex, age and stunting.

Conclusions

Malnutrition, Plasmodium and S. haematobium infections are common while anaemia is a severe public health problem in Muyuka, Cameroon. The interaction between haematological parameters with malaria parasites as well as linear growth index was negative and other interactions indicate systemic inflammation. While findings provide contextual intervention targets to ensure the judicious use of the limited resources, there is need for regular monitoring and proper treatment to improve the health of the underserved population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06201-9.

Association of low birth weight and polyparasitic infection during pregnancy in Lambaréné, Gabon

OBJECTIVE

To report the prevalence of polyparasitism during pregnancy in the Lambaréné region of Gabon and its association with newborn birth weight.

METHOD

Pregnant women in their third trimester were recruited in a prospective study between November 2011 and March 2015. Parasite infection status was assessed microscopically in stool, urine and blood samples. Maternal demographic and obstetrical characteristics and newborns anthropometric data were collected. Multivariable logistic regression was used to assess the association between low birth weight and polyparasitism.

RESULTS

678 of 927 pregnant women were included for analysis with mean age (SD) of 25 (6.8) years. The analysis showed that 69% (468/678) were infected with at least one parasite (Plasmodium spp., Schistosoma spp., soil-transmitted helminths, filarial infections). This comprised of 38% with monoparasitism and 31% polyparasitism. The proportion of newborn babies with a weight below 2500 g (LBW) in our study was 21% (142/678). Compared to pregnant women without infection, women with monoparasitic infection had adjusted Odds Ratio confidence interval 95% CI (aOR [95%CI]) of 1.6 [0.95-2.73], those with two parasites had aOR 95%CI of 2.63 [1.51-4.62], and those with more than two parasites had aOR of 5.08 [2.5-10.38] for delivering a newborn with low birth weight.

CONCLUSION

In Lambaréné, an endemic area for multiple parasite infections, there is a high prevalence of polyparasitism in pregnant women. Polyparasitism is associated with low birth weight. Therefore, there is an urgent need for active screening and treatment of parasite infections in pregnant women to assess the potential public health benefit of such interventions.

Prevalence of schistosomiasis and its association with anemia among pregnant women: a systematic review and meta-analysis

BACKGROUND

Schistosomiasis is a highly prevalent parasitic disease that can lead to adverse maternal and perinatal outcomes. To our knowledge, there has been no systematic review and meta-analysis of schistosomiasis during pregnancy.

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Relevant published studies were searched in international databases (PubMed, Science Direct, Scopus, Web of Science, and Google Scholar), from their inception until May 31, 2020. The retrieved studies were assessed for quality using the Modified Newcastle-Ottawa Scale. OpenMeta Analyst software was used for the statistical analysis.

RESULTS

Thirty-two studies enrolling 21024 pregnant women were included in this meta-analysis. All 32 of these studies were conducted in Africa. Of these studies, 19, 11, and 2 investigated S. mansoni, S. haematobium, and combined S. mansoni and S. haematobium infections, respectively. The pooled prevalence estimate of schistosomiasis during pregnancy was 13.2% (95 CI 11.0-15.4). A random model was used because of high heterogeneity (Q = 99.14; P < 0.001). In subgroup analyses, the pooled prevalence estimate of S. haematobium was significantly higher than the pooled prevalence estimates of S. mansoni [22.5% (95% CI 1.6-43.5) vs 8.7% (95% CI 6.0-11.3, P = 0.016), respectively]. The results of meta-regression analyses showed a non-significant difference in the prevalence of schistosomiasis during pregnancy according to the study sample sizes and year of publication. Only six studies evaluated the association between schistosomiasis during pregnancy and anemia. Schistosomiasis was associated with anemia in these six studies (OR = 3.02, 95% = 1.25‒7.28, P = 0.014).

CONCLUSION

The present meta-analysis suggests that schistosomiasis during pregnancy is an existing health problem. This meta-analysis also highlights the lack of data on the determinants and outcomes of schistosomiasis during pregnancy. Preventive measures are needed and could be part of antenatal care in areas endemic with schistosomiasis.

Polyparasitism with Schistosoma haematobium, Plasmodium and soil-transmitted helminths in school-aged children in Muyuka-Cameroon following implementation of control measures: a cross sectional study

Background

Despite the ubiquity of polyparasitism, its health impacts have been inadequately studied. The aim of this study was to determine the prevalence and determinants of polyparasitism with Schistosoma haematobium, Plasmodium and soil-transmitted helminths (STH) following sustained control measures, as well as evaluate the outcomes and clinical correlates of infection in school-aged children (SAC) living in the schistosomiasis endemic focus of Muyuka-Cameroon.

Methods

In a cross-sectional study, urine, blood and stool samples were each collected from SAC (4–14 years) selected at random between March and June 2015. Microhaematuria in urine was detected using reagent strip and S. haematobium ova by filtration/microscopy methods. Plasmodium was detected using Giemsa-stained blood films and complete blood count was obtained using an auto-haematology analyser. STH in stool was detected by the Kato-Katz method. Categorical and continuous variables were compared as required, Kappa value estimated and the adjusted odds ratio (aOR) in the multivariate analysis was used to evaluate association of the risk factors with infection.

Results

Out of the 638 SAC examined, single infection was prevalent in 33.4% while polyparasitism was 19.9%. Prevalence of S. haematobium + Plasmodium was 7.8%; S. haematobium + STH was 0.8%; Plasmodium + STH was 0.8%; while S. haematobium + Plasmodium + STH was 0.9%. Higher preponderance of S. haematobium + Plasmodium infection occurred in females, those from Likoko, did not use potable water, practiced bathing in stream and carried out open defecation than their equivalents. However, being female (aOR = 2.38, P = 0.009) was the only significant risk factor identified. Anaemia was a common morbidity (74.3%) with a slight agreement with microscopy in predicting S. haematobium and Plasmodium infections. The sensitivity and specificity of haematuria (13.0%) in predicting S. haematobium infection was 46.5% and 100% with a moderate agreement with microscopy. Co-infection with S. haematobium and malaria parasite was significantly associated with threefold odds of history of fever in the last three days.

Conclusions

Polyparasitism is a public health problem in Muyuka with females most at risk. Anaemia prevalence is exacerbated in co- and triple-infections and together with a history of fever are of value in predicting polyparasitism.

The epidemiological status of urogenital schistosomiasis among reproductive aged individuals in the Tiko Health Area- a semi-urban setting in the Mount Cameroon area

BACKGROUND

Urogenital schistosomiasis (UGS) caused by S. haematobium has enormous reproductive health consequences including infertility. Reproductive aged individuals are a neglected group and not included in control programs in Cameroon. This study investigated the prevalence and severity of S. haematobium infection in the context of gender and socio-economic structures that shape behaviour among reproductive aged individuals living in Tiko, a semi-urban setting, Cameroon.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional study was carried out in the Tiko Health District (THD) between May to September 2019. Consenting individuals were enrolled using a convenient sampling technique and administered a semi-structured questionnaire to document data on socio-demographic and stream contact behaviour. A urine sample was collected and screened for the presence of S. haematobium ova using reagent strips, filtration and microscopy. The overall prevalence of S. haematobium infection was 22.8% (95% CL: 19.27-26.73) with geometric mean egg load of 18.74 (range: 1-1600) per 10ml of urine. Younger age group (15 - 20years) (OR: 5.13; 95% CL: 1.35-19.42), male (OR: 2.60 3.07; 95% CL: 1.54-4.40) and awareness of UGS (OR: 1.73; 95% CL: 1.02-2.95) were associated with higher odds of exposure to infection. Significantly higher intensity of infection was seen in males, singles and in the age group 15-30 years. It is worth noting that males carried out more activities which entailed longer duration in streams.

CONCLUSION/SIGNIFICANCE

The prevalence obtained shows that Tiko is a moderate-risk area for UGS with underlying morbidity-inducing infection intensity. The severity of the infection is more in males. Awareness of the disease is not enough to protect these communities from infection, but provision of public infrastructures and health education will limit contact with infested water and thus curtail the infection. There is an urgent need to involve all age groups in control programs.

Coverage and effectiveness of intermittent preventive treatment in pregnancy with sulfadoxine-pyrimethamine (IPTp-SP) on adverse pregnancy outcomes in the Mount Cameroon area, South West Cameroon

Background

Growing concerns about the waning efficacy of IPTp-SP warrants continuous monitoring and evaluation. This study determined coverage of IPTp-SP and compared the effectiveness of the 3-dose to 2-dose regimen on placental malaria (PM) infection and low birth weight (LBW) in the Mount Cameroon area.

Methods

Consenting pregnant women were enrolled consecutively through a cross-sectional survey at delivery at four antenatal clinics, two each from semi-rural and semi-urban settings from November 2016 to December 2017. Reported IPTp-SP use, demographic and antenatal clinic (ANC) data of the mothers and neonate birth weights were documented. Maternal haemoglobin concentration was measured using a haemoglobinometer and PM infection diagnosed by placental blood microscopy. Logistic regression analysis was used to model study outcomes.

Results

Among the 465 parturient women enrolled, 47.0% (203), 34.7% (150), 18.3% (79) and 7.1% (33) reported uptake of ≥ 3, 2.1 dose(s) and no SP, respectively. Uptake of ≥ 3 doses varied significantly (p < 0.001) according to type of medical facility, timing of ANC initiation and number of ANC visits. The prevalence of PM was 18.5% where uptake of ≥ 3 SP doses (AOR = 2.36: 95% CI  1.41–4.87), primiparity (AOR = 2.13: 95% CI  1.19–3.81), semi-rural setting (AOR = 1.85: 95% CI  1.12–3.04) increased odds of infection. Also, three or more dosing was associated (p < 0.001) with increased PM density notably among women from semi-urban areas. Compared with third trimester, ANC initiation in the second trimester (AOR: 0.39: 95% CI  0.20–0.74) lower odds of infection. The prevalence of LBW infants was 7.3% and were generally those of anaemic (AOR: 4.6: 95% CI  1.03–20.57) and semi-rural (AOR: 5.29: 95% CI  1.73–16.15) women. Although ≥ 3 (AOR: 0.31: 95% CI  0.11–0.87) and 2 (AOR: 0.32: 95% CI  0.11–0.93) doses of SP was associated with lower odds of LBW, ≥ 3 doses were not associated with additional increase in birth weight nor maternal haemoglobin levels when compared with 2 doses.

Conclusion

In the Mount Cameroon area, reported uptake of IPTp with ≥ 3 SP doses did not provide observable prophylactic benefits. SP resistance efficacy studies are necessary.

Chemokine, cytokine and haematological profiles in Sprague-Dawley rats co-infected with Plasmodium berghei ANKA and Trichinella zimbabwensis-A laboratory animal model for malaria and tissue-dwelling nematodes co-infection

Malaria remains a major cause of mortality and morbidity in sub-Saharan Africa (SSA) and tissue-dwelling helminth parasites (TDHPs) are also prevalent in this region presenting a geographical overlap in endemicity. There is paucity of information on the specific host immune responses elicited at different phases of the life cycle by the co-infecting helminth parasites. This study aimed at using a laboratory animal model to determine selected chemokine, cytokine and hematological profiles in Sprague-Dawley rats co-infected with Plasmodium berghei ANKA (Pb) and a tissue-dwelling nematode, Trichinella zimbabwensis (Tz). One-hundred-and-sixty-eight male Sprague-Dawley rats (90–150g) were randomly divided into four experimental groups; Control (n = 42), Pb-infected (n = 42), Tz-infected (n = 42) and Pb + Tz-infected group (n = 42). Trichinella zimbabwensis infection (3 muscle larvae/g body weight per os) was done on day 0 while intra-peritoneal Pb infection (10⁵ parasitised RBCs) was done at day 28 of the 42-day experimental study for the co-infection group which corresponded with day 0 of the Pb group on the protocol. Haematological parameters, cytokines (TNF-α, IL-10, IL-4, IL-6), chemokines (CXCL10, CCL5, CCL11) and burden of Tz adult worms and muscle larvae burden were determined as per need for each group. Results showed that Tz infection predisposed the co-infected animals towards rapid development of Pb parasitaemia during co-infection, reaching a higher peak percentage parasitaemia at day 7 post-infection than the Pb mono-infected group at day 6 post-infection. Animals in the co-infected group also exhibited severe anaemia, basophilia, neutrophilia, eosinophilia and lymphopenia at day 7 post Pb infection compared to the control groups. Significant elevation of Pb parasitaemia coincided with elevated pro-inflammatory cytokine TNF-α (P < 0.001), regulatory anti-inflammatory IL-10 (P < 0.001), and pro-inflammatory chemokines CXCL10 (P < 0.001) concentration in comparison to control group, at day 7 post Pb infection. Our results confirm that co-infection of Pb with Tz resulted in increased Pb parasitaemia compared to the control group in the early stages of infection and this might translate to severe malaria.

Evaluation of Urine Reagent Strip as a Tool for Routine Diagnosis of Maternal Urogenital Schistosomiasis at Antenatal Clinic Visit in Munyenge, South West Region, Cameroon

Urine reagent strip used in detecting microhaematuria has been recommended in pregnancy for diagnosis of urogenital schistosomiasis (UGS) during routine antenatal care (ANC). This study evaluated its sensitivity, specificity, and predictive values in the diagnosis of maternal UGS using filtration method as a reference test. We also assessed the variation in its performance in the diagnosis of UGS using multiple-sample collection. A total of 93 pregnant women reporting for first ANC clinic visit at any of the three functional health care centres (Munyenge Integrated Health Centre, Banga Annex Health Centre, and Trans African Health Centre) were enrolled and followed up for three consecutive monthly visits. Urine samples were observed microscopically for S. haematobium egg using urine filtration and screened for microhaematuria and proteinuria using urine reagent strips. Twenty-two (23.7%) out of the 93 women were diagnosed for UGS, all of whom showed S. haematobium egg excretion during all three visits. There was a significant difference (p < 0.001) between the prevalence of S. haematobium infection and the prevalence of microhaematuria. The intensity of infection was significantly higher in microhaematuria-positive women compared with microhaematuria-negative cases. Sensitivity of reagent strip ranged from 54.5 to 59.1%, while specificity was above 98.0% (range: 98.6-100%). The measure of agreement between urine filtration and reagent strip method was substantial (0.61-0.8) irrespective of different sampling periods. Urine reagent strip is a moderately sensitive method in the detection of UGS and will most likely identify women with high egg load burden. Proper diagnosis of schistosomiasis during pregnancy is recommended.

Health system, socio-cultural, economic, environmental and individual factors influencing bed net use in the prevention of malaria in pregnancy in two Ghanaian regions

Background

Improving maternal health remains a priority to the Ghanaian government. Consequently, it has implemented the World Health Organization recommendation of distributing free long-lasting insecticidal nets (LLINs) to pregnant women—one of the effective strategies to combating malaria in pregnancy. However, the burden of negative outcomes of malaria in pregnancy such as low birth weight and miscarriages is still high. This may be related to the health system, socio-cultural and economic dynamics that influence LLIN use, but their role is not well understood. This ethnographic study sought to understand health system, socio-cultural, economic and environmental dynamics in utilization of LLINs among pregnant women in two Ghanaian regions.

Methods

An ethnographic study design was used. In-depth interviews and conversations were conducted among health workers, pregnant women and opinion leaders. Observations were conducted in 12 communities and eight health facilities. Ethical clearance was obtained from the University of Health and Allied Sciences’ Research Ethics Committee. Nvivo 11 was used to support data coding. Data were triangulated and analysed using a thematic approach.

Results

Findings suggest health system, socio-cultural, economic, environmental and individual factors influenced LLIN use. Health facility readiness in stocking LLINs influenced ownership and use. Receiving appropriate information from health providers and encouragement from public officials improved LLIN use. Women with a history of LLIN use prior to becoming pregnant and women who had young children remained consistent users. Experiencing irritating effects of LLINs and preference for traditional methods to wade off mosquitoes, reduced LLIN use. Pregnant women whose household and family members used LLINs were influenced positively to use them. Gender power relations between husbands and wives influenced women’s use of LLINs. The type of housing and weather conditions contributed to inconsistent use. Staying out late for business purposes and to converse, exposed pregnant women to mosquito bites.

Conclusion

Giving out LLINs at facility level should be accompanied with comprehensive information, which is relevant to the socio-cultural context that women live in. Mass distribution should factor in individual and public information to promote community acceptance and proper use of ITNs. Facilities should be encouraged to constantly maintain LLINs stock in order to ensure that ANC registrants receive LLINs for use.

Prevalence and Risk Factors Associated with S. haematobium Egg Excretion during the Dry Season, Six Months following Mass Distribution of Praziquantel (PZQ) in 2017 in the Bafia Health Area, South West Region Cameroon: A Cross-Sectional Study

Background

A selective population mass drug administration of PZQ involving school-aged children was carried out in the Bafia Health Area in April 2017. This study investigated the prevalence, intensity, and factors associated with S. haematobium egg excretion in this foci during the dry season, six months after the chemotherapy campaign.

Methods

A cross-sectional study including 1001 consenting individuals (aged 3-62 years) was carried out in three localities (Ikata, Bafia, and Munyenge) in the Bafia Health Area between November 2017 and January 2018. Information on sociodemographic, stream usage, and contact behaviour was documented. Schistosoma haematobium ova in urine were detected using membrane filtration technique.

Results

The prevalence of S. haematobium egg excretion was 8% with a higher level recorded in Munyenge (13.2%) than Ikata (7.5%) and Bafia (2.8%). The difference was significant (p < 0.001). Equally, Munyenge had the highest infection intensity (36.36 range: 2-200) when compared with Ikata (16.25 range: 2-57) and Bafia (8.0 range: 0-8). Although the age group (5–15 years) was significantly (p < 0.001) associated with more exposure to infested water, this group was less likely (OR: 0.42 95% CI: 0.19-0.91) associated with S. haematobium egg excretion. The risk of egg excretion increased by 4.79 times (95% CI: 2.20-10.41) and 3.68 times (95% CI: 1.59-8.54) among residents in Munyenge and Ikata, respectively. Similarly, frequency to the stream (> thrice/day) was significantly higher (χ² = 58.73; p < 0.001) in Munyenge. Frequent contact (three visits/day) with stream correlated with highest odds of egg excretion (OR: 8.43 95% CI: 3.71-19.13).

Conclusion

The prevalence of S. haematobium egg excretion was low during the dry season. This was most likely attributed to the preventive campaign with PZQ and may parallel low transmission potentials in infested waters during this period.

Schistosoma haematobium infection status and its associated risk factors among pregnant women in Munyenge, South West Region, Cameroon following scale-up of communal piped water sources from 2014 to 2017: a cross-sectional study

Background

In 2014, a study in Munyenge revealed a high prevalence of urogenital schistosomiasis (UGS) among pregnant women. This study investigated he prevalence and risk factors of UGS in pregnancy following scale-up of piped water sources from 2014 to 2017. Secondly, we compared stream usage, stream contact behaviour, infection rate and intensity with the findings of 2014.

Methods

Consenting pregnant women reporting for antenatal care (ANC) in the different health facilities were enrolled consecutively between November 2016 and January 2018. Information on age, gravidity status, residence, marital status, educational level, occupation, household water source, frequency of contact with water and stream activities were obtained using a semi-structured questionnaire. Urine samples were examined for the presence of microhaematuria and S. haematobium ova using test strip and filtration/microscopy methods respectively. Data were analysed using univariate and multivariate regression analyses and relative risk reductions calculated.

Results

Of the 368 women enrolled, 22.3% (82) were diagnosed with UGS. Marital status (single) (aOR = 2.24, 95% CI: 1.04–4.79), primary - level of education (aOR = 2.0; 95% CI: 1.04–3.85) and domestic activity and bathing in the stream (aOR = 3.3; 95% CI: 1.83–6.01) increased risk of S. haematobium infection. Meanwhile, fewer visits (< 3 visits/week) to stream (aOR = 0.35, 95% CI = 0.17–0.74) reduced exposure to infection. Piped water usage was associated with reduced stream usage and eliminated the risk of infection among women who used safe water only. Compared with the findings of 2014, stream usage (RRR = 23 95% CI: 19–28), frequency (≥ 3 visits) (RRR = 69 95% CI: 59–77) and intensity of contact with water (RRR = 37 95% CI = 22–49) has reduced. Similarly, we observed a decrease in infection rate (RRR = 52, 95% CI = 40–62) and prevalence of heavy egg intensity (RRR = 71, 95% CI = 53–81).

Conclusion

Following increased piped water sources in Munyenge, S. haematobium infection has declined due to reduced stream contact. This has important implication in the control of UGS in pregnancy.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-6659-7) contains supplementary material, which is available to authorized users.

Biochemical and hematological changes among anemic and non-anemic pregnant women attending antenatal clinic at the Bolgatanga regional hospital, Ghana

BACKGROUND

Anemia in pregnancy may not only be associated with maternal morbidity and mortality but can also be detrimental to the fetus. A definitive diagnosis of anemia is a pre-requisite to unravelling possible cause(s), to allow appropriate treatment intervention. It is hypothesised that measured hemoglobin (HGB), complemented by biochemical and other hematological parameters would enhance anemia diagnosis.

METHODS

This was a cross-sectional study among 400 pregnant women comprising 253 anemic and 147 non-anemic pregnant women, attending an antenatal clinic at Bolgatanga Regional Hospital, Ghana. Venous blood was collected and hemoglobin genotype, complete blood count and biochemical parameters [ferritin, iron, total iron binding capacity (TIBC), transferrin saturation (TfS), C-reactive protein (CRP) and bilirubin] were determined. Thick blood films were prepared for malaria parasitemia, while early morning stool and midstream urine samples were examined for enteric and urogenital parasites, respectively.

RESULTS

There were significantly reduced levels of HGB (p < 0.0001), HCT (p < 0.0001), MCV (p < 0.0001), iron (0.0273), ferritin (p = 0.018) and transferrin saturation (0.0391) and increased WBC (p = 0.006), RDW (p = 0.0480), TIBC (p = 0.0438) and positivity of CRP in anemic, compared to non-anemic pregnant women. Anemic women were associated with increased proportion of hemoglobinopathies (AS, SS and SC), Plasmodium falciparum, Schistosoma hematobium and intestinal parasite infections.

CONCLUSION

Anemic pregnant women are associated with a significant derangement in hematological and iron indices that implicate iron deficiency. This was influenced by hemoglobinopathies and parasitic infections.

Schistosoma haematobium effects on Plasmodium falciparum infection modified by soil-transmitted helminths in school-age children living in rural areas of Gabon

BACKGROUND

Malaria burden remains high in the sub-Saharan region where helminths are prevalent and where children are often infected with both types of parasites. Although the effect of helminths on malaria infection is evident, the impact of these co-infections is not clearly elucidated yet and the scarce findings are conflicting. In this study, we investigated the effect of schistosomiasis, considering soil-transmitted helminths (STH), on prevalence and incidence of Plasmodium falciparum infection.

METHODOLOGY

This longitudinal survey was conducted in school-age children living in two rural communities in the vicinity of Lambaréné, Gabon. Thick blood smear light microscopy, urine filtration and the Kato-Katz technique were performed to detect malaria parasites, S. haematobium eggs and, STH eggs, respectively. P. falciparum carriage was assessed at inclusion, and incidence of malaria and time to the first malaria event were recorded in correlation with Schistosoma carriage status. Stratified multivariate analysis using generalized linear model was used to assess the risk of plasmodium infection considering interaction with STH, and survival analysis to assess time to malaria.

MAIN FINDINGS

The overall prevalence on subject enrolment was 30%, 23% and 9% for S. haematobium, P. falciparum infections and co-infection with both parasites, respectively. Our results showed that schistosomiasis in children tends to increase the risk of plasmodium infection but a combined effect with Trichuris trichiura or hookworm infection clearly increase the risk (aOR = 3.9 [95%CI: 1.7-9.2]). The incidence of malaria over time was 0.51[95%CI: 0.45-0.57] per person-year and was higher in the Schistosoma-infected group compared to the non-infected group (0.61 vs 0.43, p = 0.02), with a significant delay of time-to first-malaria event only in children aged from 6 to 10-years-old infected with Schistosoma haematobium.

CONCLUSIONS

Our results suggest that STH enhance the risk for P. falciparum infection in schistosomiasis-positive children, and when infected, that schistosomiasis enhances susceptibility to developing malaria in young children but not in older children.

Co-infection: the outcome of Plasmodium infection differs according to the time of pre-existing helminth infection

Although helminth-Plasmodium coinfections are common in tropical regions, the implications of this co-existence for the host immune response are poorly understood. In order to understand the effect of helminth infection at different times of coinfection on the immune response against Plasmodium infection, BALB/c mice were intraperitoneally infected with Taenia crassiceps (Tc). At 2 (Tc2) or 8 (Tc8) weeks post-infection, mice were intravenously infected with 1 × 10³ Plasmodium yoelii (Py) 17XL-parasitized red blood cells. Py 17XL-single-infected mice developed cachexia, splenomegaly, and anemia, and died at 11 days post-infection. Importantly, Tc2 + Py-coinfected mice showed increased survival of 58% on day 11, but developed pathology (cachexia and splenomegaly) and succumbed on day 18 post-coinfection, this latter associated with high levels of IL-1β and IL-12, and reduced IFN-γ in serum compared with Py 17XL-single-infected mice. Interestingly, Tc8 + Py-coinfected mice showed increased survival up to 80% on day 11 and succumbed on day 30 post-coinfection. This increased survival rate conferred by chronic helminth infection was associated with a decreased pathology and mixed inflammatory-type 1/anti-inflammatory-type 2 immune profile as evidenced by the production of high levels of IL-12 and IL-10, and reduced TNF-α from macrophages, high levels of IL-4 and IL-10, and low levels of IFN-γ from spleen cells. Also high serum levels of IL-1β, TNF-α, IL-12, IL-4, and IL-10, but a significant reduction of IFN-γ were observed. Together, these data indicate that polarization of the cell-mediated response modulated by a pre-existing helminth infection differentially impacts on the host immune response to Py 17XL in a time-dependent manner.