Helicobacter pylori (H. pylori) risk factor analysis and prevalence prediction: a machine learning-based approach

Background

Although previous epidemiological studies have examined the potential risk factors that increase the likelihood of acquiring Helicobacter pylori infections, most of these analyses have utilized conventional statistical models, including logistic regression, and have not benefited from advanced machine learning techniques.

Objective

We examined H. pylori infection risk factors among school children using machine learning algorithms to identify important risk factors as well as to determine whether machine learning can be used to predict H. pylori infection status.

Methods

We applied feature selection and classification algorithms to data from a school-based cross-sectional survey in Ethiopia. The data set included 954 school children with 27 sociodemographic and lifestyle variables. We conducted five runs of tenfold cross-validation on the data. We combined the results of these runs for each combination of feature selection (e.g., Information Gain) and classification (e.g., Support Vector Machines) algorithms.

Results

The XGBoost classifier had the highest accuracy in predicting H. pylori infection status with an accuracy of 77%—a 13% improvement from the baseline accuracy of guessing the most frequent class (64% of the samples were H. Pylori negative.) K-Nearest Neighbors showed the worst performance across all classifiers. A similar performance was observed using the F1-score and area under the receiver operating curve (AUROC) classifier evaluation metrics. Among all features, place of residence (with urban residence increasing risk) was the most common risk factor for H. pylori infection, regardless of the feature selection method choice. Additionally, our machine learning algorithms identified other important risk factors for H. pylori infection, such as; electricity usage in the home, toilet type, and waste disposal location. Using a 75% cutoff for robustness, machine learning identified five of the eight significant features found by traditional multivariate logistic regression. However, when a lower robustness threshold is used, machine learning approaches identified more H. pylori risk factors than multivariate logistic regression and suggested risk factors not detected by logistic regression.

Conclusion

This study provides evidence that machine learning approaches are positioned to uncover H. pylori infection risk factors and predict H. pylori infection status. These approaches identify similar risk factors and predict infection with comparable accuracy to logistic regression, thus they could be used as an alternative method.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07625-7.

Common hematological parameters reference intervals for apparently healthy pregnant and non-pregnant women of South Wollo Zone, Amhara Regional State, Northeast Ethiopia

Background

Hematological reference intervals (RIs) are affected by inherent variables like age, sex, genetic background, environment, diet and certain circumstances such as pregnancy signifying the need for population specific values. This study was designed to establish RIs for common hematological parameters of apparently healthy pregnant and non-pregnant women from Northeast Ethiopia.

Method

This community based cross-sectional study recruited 600 pregnant and non-pregnant women in South Wollo Zone, Northeast Ethiopia from June to August 2019. Complete blood count was performed for eligible participants using Mindary BC-3000 plus hematology analyzer. The mean, median, and 2.5^th and 97.5^th percentile reference limits with 90% CI were determined using SPSS version 23.

Result

The established selected 2.5^th–97.5^th percentiles RIs for pregnant women were: WBC: 4.0–13.2x10⁹/L; RBC: 3.45–4.67x10¹²/L; Hgb: 10.1–13.7g/dL; HCT: 33.5–46.5%; MCV: 85-104fL; MCH: 27.5–33.0pg; MCHC: 30.3–33.7g/dL and Platelet count: 132-373x10⁹/L. The respective values for non-pregnant women were 3.6–10.3; 4.44–5.01; 12.4–14.3; 38.4–50.1; 86–102; 27.1–32.4, 30.4–34.1, 173–456. A statistically significant difference between pregnant and non-pregnant women was noted in all hematological parameters except MCHC. The mean and median value of WBC count, MCV, MPV and PDW increased, whereas mean values of HCT and Platelet count decreased as gestational period advances.

Conclusion

The observed difference from other studies signify the necessity for using trimester specific RIs and separate RI for pregnant and non-pregnant women. Thus, we recommend the health facilities in the study area to utilize the currently established RIs for pregnant and non-pregnant women for better care.

Effect of sample management on quantitative HIV-1 viral load measurement at Saint Paul’s Hospital Millennium Medical College, Addis Ababa, Ethiopia

Purpose

This study was meant to determine the effect of time to plasma separation, storage duration, freeze-thawing cycle and dilution proportion on the HIV-1 viral load level.

Methods

Experimental study design was employed by collecting 10mL whole blood samples into two EDTA tubes from 88 eligible HIV infected patients at St Paul’s Hospital Millennium Medical College. The viral load test was done using Abbott m2000sp/rt analyzer. Data was entered into Microsoft excel and analyzed by SPSS version 20. Repeated measure analysis of variance was used to compare HIV RNA viral load mean difference between different time to plasma separation, storage, freeze-thawing cycles and dilution levels. Post-hoc analysis was employed to locate the place of significant differences. P value less than 0.05 was used to declare statistical significance while viral RNA level of 0.5 log copies/ml was used to determine clinical significance.

Results

There was significant HIV-1 RNA viral load log mean difference between plasma separation time at 6 hours (hrs) and 24hrs (p<0.001). There was also significant HIV-1 RNA viral load log mean difference between plasma tested within 6hrs and those stored at 2–8°C for 15 days (p = 0.006), and between plasma stored at 2–8°C for 6 days versus 15 days (p<0.001). There was significant log mean difference between plasma that was exposed to fourth cycle of freeze-thawing after storage at -20°C when compared with plasma tested within 6hrs (p = 0.013).

Conclusion

Plasma separated at 24hrs, stored at 2–8°C for 15 days or freeze-thawed for four cycles had significant effect on HIV viral load level. However, the differences were not clinically significant at a cut-off viral load level of 0.5 log copies/ml. Avoiding delays to plasma separation beyond 24 hrs, storing at 2–8°C for 15 days and freeze-thawing for no more than 4 cycles is recommended to improve the result quality.

Machine learning-based risk factor analysis and prevalence prediction of intestinal parasitic infections using epidemiological survey data

Background

Previous epidemiological studies have examined the prevalence and risk factors for a variety of parasitic illnesses, including protozoan and soil-transmitted helminth (STH, e.g., hookworms and roundworms) infections. Despite advancements in machine learning for data analysis, the majority of these studies use traditional logistic regression to identify significant risk factors.

Methods

In this study, we used data from a survey of 54 risk factors for intestinal parasitosis in 954 Ethiopian school children. We investigated whether machine learning approaches can supplement traditional logistic regression in identifying intestinal parasite infection risk factors. We used feature selection methods such as InfoGain (IG), ReliefF (ReF), Joint Mutual Information (JMI), and Minimum Redundancy Maximum Relevance (MRMR). Additionally, we predicted children’s parasitic infection status using classifiers such as Logistic Regression (LR), Support Vector Machines (SVM), Random Forests (RF) and XGBoost (XGB), and compared their accuracy and area under the receiver operating characteristic curve (AUROC) scores. For optimal model training, we performed tenfold cross-validation and tuned the classifier hyperparameters. We balanced our dataset using the Synthetic Minority Oversampling (SMOTE) method. Additionally, we used association rule learning to establish a link between risk factors and parasitic infections.

Key findings

Our study demonstrated that machine learning could be used in conjunction with logistic regression. Using machine learning, we developed models that accurately predicted four parasitic infections: any parasitic infection at 79.9% accuracy, helminth infection at 84.9%, any STH infection at 95.9%, and protozoan infection at 94.2%. The Random Forests (RF) and Support Vector Machines (SVM) classifiers achieved the highest accuracy when top 20 risk factors were considered using Joint Mutual Information (JMI) or all features were used. The best predictors of infection were socioeconomic, demographic, and hematological characteristics.

Conclusions

We demonstrated that feature selection and association rule learning are useful strategies for detecting risk factors for parasite infection. Additionally, we showed that advanced classifiers might be utilized to predict children’s parasitic infection status. When combined with standard logistic regression models, machine learning techniques can identify novel risk factors and predict infection risk.

In developing countries such as Ethiopia, intestinal parasites are a significant public health problem. These parasites are detrimental to the health of schoolchildren. Numerous risk factors for parasitic infections have been identified using uni- and multi-variate logistic regression. However, logistic regression has inherent limitations when applied to data sets with a large number of risk factors. We used machine learning techniques in conjunction with logistic regression models to identify relevant risk factors for parasitic infections in a dataset of 954 Ethiopian schoolchildren with 54 different risk factors for parasitic infections. Additionally, we developed predictive models of parasitic infection. Compared to logistic regression, we discovered that machine learning techniques identified novel risk factors and had higher predictive accuracy. Furthermore, we discovered that infection prediction could be aided by combining socioeconomic, health, and hematological characteristics. As a result, we concluded that advanced machine learning methods should be used in conjunction with logistic regression to study parasitic infections.

Severe Acute Respiratory Syndrome Coronavirus 2 Infection and Pregnancy in Sub-Saharan Africa: A 6-Country Retrospective Cohort Analysis

BACKGROUND

Few data are available on COVID-19 outcomes among pregnant women in sub-Saharan Africa (SSA), where high-risk comorbidities are prevalent. We investigated the impact of pregnancy on SARS-CoV-2 infection and of SARS-CoV-2 infection on pregnancy to generate evidence for health policy and clinical practice.

METHODS

We conducted a 6-country retrospective cohort study among hospitalized women of childbearing age between 1 March 2020 and 31 March 2021. Exposures were (1) pregnancy and (2) a positive SARS-CoV-2 RT-PCR test. The primary outcome for both analyses was intensive care unit (ICU) admission. Secondary outcomes included supplemental oxygen requirement, mechanical ventilation, adverse birth outcomes, and in-hospital mortality. We used log-binomial regression to estimate the effect between pregnancy and SARS-CoV-2 infection. Factors associated with mortality were evaluated using competing-risk proportional subdistribution hazards models.

RESULTS

Our analyses included 1315 hospitalized women: 510 pregnant women with SARS-CoV-2, 403 nonpregnant women with SARS-CoV-2, and 402 pregnant women without SARS-CoV-2 infection. Among women with SARS-CoV-2 infection, pregnancy was associated with increased risk for ICU admission (adjusted risk ratio [aRR]: 2.38; 95% CI: 1.42-4.01), oxygen supplementation (aRR: 1.86; 95% CI: 1.44-2.42), and hazard of in-hospital death (adjusted sub-hazard ratio [aSHR]: 2.00; 95% CI: 1.08-3.70). Among pregnant women, SARS-CoV-2 infection increased the risk of ICU admission (aRR: 2.0; 95% CI: 1.20-3.35), oxygen supplementation (aRR: 1.57; 95% CI: 1.17-2.11), and hazard of in-hospital death (aSHR: 5.03; 95% CI: 1.79-14.13).

CONCLUSIONS

Among hospitalized women in SSA, both SARS-CoV-2 infection and pregnancy independently increased risks of ICU admission, oxygen supplementation, and death. These data support international recommendations to prioritize COVID-19 vaccination among pregnant women.

Reference Intervals for Common Renal and Liver Function Clinical Chemistry Parameters Among Apparently Healthy Pregnant and Non-pregnant Women in South Wollo Zone, Amhara National Regional State, Northeast Ethiopia

Background

Physiological changes during pregnancy cause alterations in concentration of biochemical analytes. Thus, locally established pregnancy-specific reference intervals are important for accurate diagnosis, treatment, and prognosis of diseases. The objective of the study was to establish reference interval for the common renal and liver function clinical chemistry parameters among pregnant and non-pregnant women of South Wollo zone, Ethiopia.

Methods

A community-based cross-sectional study was conducted on a total of 323 apparently healthy study participants randomly selected from South Wollo zone, Ethiopia, from April to June 2019. Medical history, physical examination and sociodemography were collected by using questionnaire. Liver and renal function clinical chemistry tests were done using A25 Biosystems, clinical chemistry analyzer. After the exclusion of outliers, Kolmogorov–Smirnov test was used to check its normality. The 95% RI with 95% confidence interval was established using the nonparametric method. The significance of differences was evaluated using Mann–Whitney U test.

Result

There was statistically significant variation between pregnant and non-pregnant women in values of albumin, T. protein, ALP, urea and creatinine, but not for AST, ALT, bilirubin (direct) and bilirubin (total). Reference intervals established for pregnant women includes albumin 26.14–42.87g/L, total protein 48.52–74.71 g/L, AST 2.4–43.6 U/L, ALT 0.94–28.35 U/L, ALP 21.2–337 U/L, bilirubin (direct) 0.03–0.32 mg/dL, bilirubin (total) 0.26–0.94 mg/dL, creatinine 0.29–0.87 mg/dL, urea 7.17–20.82 mg/dL. Albumin: 32.81–47.87, total protein: 56.71–83.9 U/L, AST: 4.2–37.1 U/L, ALT: 2.69–41.18 U/L, ALP: 3.22–278.7 U/L, bilirubin (direct) 0.1–0.51 mg/dL, bilirubin (total) 0.24–1.06 mg/dL, creatinine 0.44–1.00 mg/dL, urea 8.07–27.87 mg/dL for non-pregnant women.

Conclusion

The study showed marked difference in albumin, total protein, alkaline phosphatase, urea and creatinine. Therefore, physiological adaptations of pregnancy should be considered when interpreting liver and renal function tests in a pregnant woman.

Reference Intervals for Absolute and Percentage CD4+ T Lymphocytes among an Apparently Healthy Population in Addis Ababa, Ethiopia

Background

Reference intervals for clinical laboratory parameters differ based on several factors, including age, sex, genetic variation, and geographic location. This variation influences clinical decisions and treatment monitoring. Currently, Ethiopia has used adopted reference intervals from manufacturer values derived from non-Africans. Therefore, the aim this study was to determine reference intervals for absolute and percentage CD4⁺ T cells for an apparently healthy population in Addis Ababa, Ethiopia.

Methods

A community-based cross-sectional study was conducted on 361 apparently healthy people in four subcities in Addis Ababa from January to June 2019. Sociodemographic and clinical data were collected using a structured questionnaire after informed consent had been obtained. Blood samples were collected and CD4⁺ T-lymphocyte enumeration performed using a BD FACSPresto near-patient CD4 counter. Data were entered and analyzed using SPSS 20. Reference intervals were determined by a nonparametric test estimating percentiles 2.5 (lower limit) and 97.5 (upper limit) with 95% CIs. P<0.05 was considered statistically significant.

Results

A total of 337 (183 female and 154 male) healthy participants of median age 28 (IQR 17–35) years were included in the final analysis. Medians of absolute and percentage CD4⁺ T-cell counts (932.0 and 42.9, respectively) of female participants were significantly higher than male participants (802.5 and 38.7, respectively; P<0.05). Reference intervals for absolute CD4⁺ T-cell count and percentages in males were 483.8–1,310 cells/µL and 18.1–57.3 and in females 447.8–1,479.8 cells/µL and 25.6–58.9, respectively.

Conclusion

The CD4⁺ T-count reference intervals established in this study showed some inconsistency from the manufacturer’s provided values and other studies and also revealed sex differences, necessitating sex-specific locally established reference intervals.

The impact of the COVID-19 pandemic on health service use in sub-Saharan Africa

SETTING: Six hospitals in four sub-Saharan African countries.OBJECTIVE: To examine the indirect effects of COVID-19 on health service utilisation and to explore the risk of bias in studies on prediction models.DESIGN: Monthly data were analysed using interrupted time-series modelling. We used linear mixed-effect models for the analysis of antenatal care visits, institutional deliveries, vaccinations, outpatient visits and hospital admissions, and generalised linear mixed-effect models for hospital mortality.RESULTS: During 2018–2020, the six hospitals recorded a total of 57,075 antenatal care visits, 38,706 institutional deliveries, 312,961 vaccinations, 605,925 out-patient visits and 143,915 hospital admissions. The COVID-19 period was associated with decreases in vacci-nations (− 575 vaccinations, P < 0.0001), outpatient visits (− 700 visits, P < 0.0001) and hospital admission (− 102 admission, P = 0.001); however, no statistically significant effects were found for antenatal care visits (P = 0.71) or institutional deliveries (P = 0.14). Mortality rate increased by 2% per month in the pre-COVID-19 period; however, a decreasing trend (by 2% per month) was observed during the COVID-19 period (P = 0.004). Subgroup and sensitivity analyses broadly confirmed the main findings with only minor inconsistencies. A reduction in outpatient visits was also observed in hospitals from countries with a higher Stringency Index and in urban hospitals.CONCLUSIONS: The pandemic resulted in a reduction in health service utilisation. The decreases were less than anticipated from modelling studies.

Effect of Gasoline Exposure on Hematological Parameters of Gas Station Workers in Mekelle City, Tigray Region, Northern Ethiopia

Background

The adverse health effects of chronic gasoline exposure may be related to impairment of the hematopoietic system with bone marrow suppression, an increased risk of blood cell morphology abnormality and developing cancer.

Objective

To assess the effect of gasoline exposure on hematological parameters among gas station workers in Mekelle City, Tigray Region, Northern Ethiopia.

Methods

This cross-sectional study was carried out on 43 subjects (exposed group) and 77 subjects (unexposed group) with matched age and sex. Socio-demographic characteristics and duration of exposure data were collected using a structured questionnaire and an observation checklist. Sysmex XP-300 was used for hematological analysis and stained peripheral blood smear was examined for any abnormality. Data were entered and analyzed using SPSS version 23.

Results

Of exposed individuals, 28/43 (65.1%) and 49/77 (63.6%) of controls were males. The average exposure time was 5.19±4.38 years, with an average working hour of 11.74±1.89 hours/day. The mean RBC count (10¹²/L), HCT (%), HGB (g/dl) and platelets count (10⁹/L) of the exposed group were significantly lower (4.88±0.573, 43.29±3.71, 15.04±1.33 and 248.95±58.19) compared with controls (5.35±0.533, 44.95±3.10, 15.59±1.26 and 292.45±62.17) at p<0.05, respectively. The MCH (pg) (30.48±2.06 vs 29.52±1.66) and MCHC (g/dl) (34.83±0.988 vs 34.32±0.927) were significantly higher in the exposed group compared with controls (p<0.05). HCT, RBC, HGB and platelet counts were significantly decreased with increased years of exposure (p<0.05). The peripheral blood film examination revealed basophilic stippling and macrocytosis in 9.3% of the exposed group.

Conclusion

Long-term exposure to gasoline at gas stations affected RBC parameters and platelet count. A significant negative correlation was noted between duration of exposure and HGB, HCT and platelet count, warranting implementation of protective measures at gas stations.

Umbilical cord blood hematological parameters reference interval for newborns from Addis Ababa, Ethiopia

BACKGROUND

Several factors like altitude, age, sex, pregnancy, socioeconomic status, life style and race influence hematological reference interval (RIs), which are critical to support clinical decisions and to interpret laboratory data in research. Currently there are no well-established RIs for cord blood hematological parameters of newborns in Ethiopia. This study aims to generate RIs for umbilical cord blood hematological parameters of newborns from Addis Ababa, Ethiopia.

METHOD

A cross-sectional study was conducted from January 1 to March 31, 2019 on healthy, term newborns (37-42 weeks) with normal birth weight born to apparently healthy pregnant mothers who had met the eligibility criteria. From 139 newborns, 2-3ml cord blood was immediately collected from the clumped cord using EDTA tube. The samples were analyzed using Sysmex KX 21 hematology analyzer. Data was entered and the 2.5th and 97.5th percentiles (upper and lower reference limit) were determined using non parametric method by SPSS version 23. The non-parametric independent Mann-Whitney U test (Wilcoxon rank-sum test) was used to compare the distribution of the parameters between genders, modes of deliveries and gestational age. P value less than 0.05 was considered to declare statistical significance.

RESULT

The median values and 95 % reference interval for umbilical cord blood hematological parameters of newborns were as follows: WBC = 12.4 [6.6-19.4] x109/L, RBC = 4.51 [3.55-5.52] x1012/L, HGB = 15.8 [12.4-19.7] g/dL, HCT = 45.9[37.9-56.3]%, MCV = 102.1[83.9-111.6] fL, MCH = 35.3 [29.4-39.1] pg, MCHC = 34.3 [32.3-37.4] %, PLT = 236 [146-438] x109/L, LYM = 37.5 [16.6-63.0] %, MXD = 7.9[1.7-15.8] %, NEU = 53.7[30.3-78.4] %, RDW = 15.6[12.0-19.0]%, PDW = 11.0[9.1-15.7]% and MPV = 9.4[8.1-11.8] fL. The current study found no significant difference between genders, except RDW (P = 0.01), and gestational age group, but there was significant difference for WBC (p = 0.007), RBC (p = 0.018) and Absolute NEU (p = 0.001) by delivery type where newborns delivered through caesarean section had lower values for these three parameters compared to those with spontaneous delivery.

CONCLUSIONS

hematological reference intervals in cord blood were established for the first time from healthy newborns of Addis Ababa and its surrounding. The values are applicable for newborns from this area. Larger study throughout the country is warranted.

Intestinal helminthic infection and allergic disorders among school children enrolled in mass deworming program, Sululta, Ethiopia

BACKGROUND

Intestinal helminths have been proposed to have a protective role against allergic sensitization and atopic diseases. However, consistent data demonstrating this are lacking in Sub-Saharan countries. We aimed to assess the association between intestinal helminths and allergic disorders among school children enrolled in mass deworming program in Sululta, Ethiopia.

METHODS

A cross sectional study was conducted among 526 school children aged 5 to 14 years old from primary government schools in Sululta district, Ethiopia. An interviewer-led questionnaire administered to parents provided information on demographic and lifestyle variables. Questions on allergic disease symptoms were collected using the International Study of Asthma and Allergies in Children (ISAAC) questionnaire 6 months following deworming treatments. Atopy was defined as a positive skin prick test reaction to one or both dust mite (Dermatophagoides) and German cockroach (Blatella germanica) allergens. Fresh stool samples were collected, processed, and examined by direct wet mount, Kato-Katz technique, and formol-ether concentration technique. Multivariate logistic regressions were used to assess the association between allergic disorder and helminths infection.

RESULTS

Of the total 526 school children, 58.2% were females. Overall, 24% (126/526) had allergic symptoms, 5.1% (27/526) had atopy, and 16.9% (89/526) had intestinal helminths. There was no association between helminthic infection and self-reported allergic symptoms (P = 0.317), but Ascaris lumbricoides infection was positively associated with atopy (AOR = 4.307, 95% CI 1.143-16.222, P = 0.031). Atopy was related to increased allergy symptoms (AOR = 2.787, 95% CI 1.253-6.197, P = 0.012), and family history of allergy was associated with increased childhood allergy (AOR = 2.753, 95% CI 1.565-4.841, P = 0.001). Deworming in the past 6 months showed a reduced odd of self-reported allergic symptoms (AOR = 0.581, 95% CI 0.366-0.954, P = 0.034).

CONCLUSION

While no significant association between self-reported allergy and helminths was found in this study, this may have been due to the low prevalence and intensity of helminthic infection in the sample. There was a positive association between Ascaris lumbricoides and atopy. To further examine the underlying mechanism behind this positive association, a longitudinal study is needed.

Hematological reference intervals for adult population of Dire Dawa town, East Ethiopia

Background

Reference interval (RI) for hematological parameters is used to interpret laboratory test results in the diagnosis, management and monitoring of hematologic disorders. Several factors including sex, age, dietary patterns, pregnancy status, ethnicity and geographic location affect hematological RIs. However, manufacturers derived reference value is currently in use in most developing countries including Ethiopia. This study aimed to establish hematological RIs for adult population living in Dire Dawa town, East Ethiopia.

Methods

In this cross-sectional study, 513 apparently healthy adults of Dire Dawa town were enrolled from January to March 2019. From these, 342 (171 males and 171 non-pregnant females) were aged 18–65 years while 171 were pregnant women aged 15–49 years. After obtaining written informed consent, 5ml fresh whole blood was collected of which 2ml was used for hematologic analysis using Mindray BC-3000plus hematology analyzer and 3ml for serological tests. The 2.5^th and 97.5^th RI was computed by non-parametric test employing SPSS version 24. P-value <0.05 was considered statistically significant.

Result

Males had significantly higher reference value for most of red cell parameters (Hgb, RBC, HCT, MCH and MCHC) than females (p <0.05), while most of the WBC parameters were significantly higher in females than males. Moreover, non-pregnant women had higher values for most of red cell parameters than pregnant women. Pregnant women had higher WBC parameters than their non-pregnant counterparts.

Conclusion

The hematologic RIs obtained in this study shows variation between genders, between pregnant and non-pregnant women, from the clinical practice currently utilised in Dire Dawa town and from studies conducted in Ethiopia, African countries as well as the Western population. It underscores the need for utilising gender and pregnancy specific, locally derived hematologic RI for better management, diagnosis and monitoring of hematologic disorders for adults of both genders and pregnant women.

The Critical Need for Pooled Data on Coronavirus Disease 2019 in African Children: An AFREhealth Call for Action Through Multicountry Research Collaboration

Globally, there are prevailing knowledge gaps in the epidemiology, clinical manifestations, and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among children and adolescents; and these gaps are especially wide in African countries. The availability of robust age-disaggregated data is a critical first step in improving knowledge on disease burden and manifestations of coronavirus disease 2019 (COVID-19) among children. Furthermore, it is essential to improve understanding of SARS-CoV-2 interactions with comorbidities and coinfections such as human immunodeficiency virus (HIV), tuberculosis, malaria, sickle cell disease, and malnutrition, which are highly prevalent among children in sub-Saharan Africa. The African Forum for Research and Education in Health (AFREhealth) COVID-19 Research Collaboration on Children and Adolescents is conducting studies across Western, Central, Eastern, and Southern Africa to address existing knowledge gaps. This consortium is expected to generate key evidence to inform clinical practice and public health policy-making for COVID-19 while concurrently addressing other major diseases affecting children in African countries.

Prevalence of enteric pathogens, intestinal parasites and resistance profile of bacterial isolates among HIV infected and non-infected diarrheic patients in Dessie Town, Northeast Ethiopia

BACKGROUND

Enteric pathogens like Salmonella and Shigella species as well as intestinal parasites (IPs) are among the main causative agents of diarrhea in people with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), particularly in low income countries like Ethiopia. Antimicrobial resistance against commonly prescribed drugs has become a major global threat. This study, therefore, aimed at determining the magnitude of Salmonella, Shigella and IPs infections, their predicting factors, and antimicrobial susceptibility pattern among HIV infected and non-infected diarrheic patients in Dessie town, Northeast Ethiopia.

METHODS

A cross sectional study was conducted at three health facilities in Northeast Ethiopia between January 2018 and March 2018. Data on socio-demographic and associated risk factors were collected using structured questionnaire from 354 HIV infected and non-infected diarrheic outpatients. Fresh stool specimen was processed according to standard operating procedures. Data were entered and analyzed using SPSS version 22. Descriptive statistics was used to determine frequency, Bivariate and multivariate logistic regression analyses were performed to identify predicting factors associated with the outcome variable. P-value <0.05 were used to declare statistical significance.

RESULTS

Among 354 diarrheic patients, 112 were HIV infected and 242 were HIV non-infected. The overall prevalence of intestinal parasite and bacterial infection among HIV infected versus non-infected, respectively, was 26 (23.2%) and 8 (7.1%) versus 50 (20.7) and 16 (6.6%). Salmonella was the highest in both groups, 6 (5.4%) vs 11 (4.5%). Most prevalent parasite was C. parvum, 9 (8%) among HIV+ while E. histolytica/dispar 39 (16.1%) among HIV-. Having bloody plus mucoid diarrhea, not utilizing latrine and drinking river or spring water were factors significantly associated with bacterial infection. Whereas, being illiterate or having primary level education, diarrhea lasting for 6-10 days, CD4 level between 200-500 cells/μl, not washing hand with soap showed significant association with IPs. The bacterial isolates were 100% susceptible to Ceftriaxone and 95.4% to Ciprofloxacin, while 100% resistant to Ampicillin and Amoxicillin. MDR was observed among 19 (79.2%) isolates.

CONCLUSION

Preventing and controlling infection by enteric pathogens as well as IPs require strengthening intervention measures. The 100% resistance of isolates to commonly prescribed antibiotics calls for expanding antimicrobial susceptibility testing so as to select appropriate antimicrobial agent and prevent emergence of drug resistant bacteria.

Effect of pregnancy and HIV infection on detection of latent TB infection by Tuberculin Skin Test and QuantiFERON-TB Gold In-Tube assay among women living in a high TB and HIV burden setting

OBJECTIVE

To investigate the effect of pregnancy and Human immunodeficiency virus (HIV) infection on detection performances of tuberculin skin test (TST) and QuantiFERON-TB Gold In-Tube (QFTGIT) for the diagnosis of latent tuberculosis infection (LTBI) among women living in high TB and HIV endemic setting.

METHOD

A cross-sectional study was conducted among women with and without pregnancy and HIV infection. Three-hundred twenty women were enrolled in this study and were diagnosed using TST and QFTGIT for the detection of LTBI.

RESULTS

Overall prevalence of LTBI among the enrolled women was 55.6%, 46.3% and 51.1% as determined by TST, QFTGIT and concordant TST/QFTGIT results, respectively. Our study revealed that pregnancy or HIV infection reduced the rate of detection of LTBI by TST and QFTGIT tests, with the utmost effect observed in HIV-positive pregnant women. Additionally, we observed that the concordance between TST and QFTGIT among women increased with the presence of pregnancy and/or HIV infection. A history of contact with TB patients was significantly associated with positivity of TST and QFTGIT.

CONCLUSION

This study demonstrated that both pregnancy and HIV infection profoundly affected the detection performance of TST and QFTGIT, which may be associated with immunosuppression of anti-mycobacterial immunity in women with pregnancy and/or HIV infection.

Community based hematological reference intervals among apparently healthy adolescents aged 12-17 years in Mekelle city, Tigrai, northern Ethiopia: A cross sectional study

BACKGROUND

Hematological reference intervals are important in clinical and diagnostic management for the assessment of health and disease conditions. Hematological reference intervals are better to be established based on gender and age differences as these are among the main affecting factors.

OBJECTIVE

The aim of this study was to establish hematological reference intervals among apparently healthy adolescents aged 12-17 years in Mekelle City, Tigrai, Northern Ethiopia, 2019.

METHOD

A community-based cross-sectional study was conducted in 249 adolescents aged 12-17 years from December 2018 to May 2019. About 4ml of blood sample was collected from each study participant using vacutainer tube containing K2EDTA. Hematological parameters were analyzed using Sysmex KX-21N hematology analyzer (Sysmex Corporation Kobe, Japan). Data were entered and analyzed using SPSS version 23. Both parametric and non-parametric analyses were used to calculate the median and 95% of reference intervals. The 97.5th and 2.5th percentiles were calculated using descriptive statistics for the upper and lower reference limits of the study participants. Differences in reference intervals between male and female participants were evaluated using the Mann-Whitney U test.

RESULT

Among the 249 participants 122 (49%) were males and 127 (51%) were females with the median age of 14.5 (range 12 to 17) years were recruited in this study. The median and the 95% reference intervals of hematological parameters were determined. The 95% RIs were: Red blood cells (1012/Liter) 4.6-5.9 (Males) and 4.3-5.6 (Females), White blood cells (109/Liter) 2.9-9.6 (Males) and 3.4-10.2 (Females), Hemoglobin (g/dl) 12.6-17.1 (Males) and 12-15.4 (Females), Platelets (109/Liter) 138-364 (Males) and 151-462 (Females). Almost all of the hematological parameters showed significant differences (p<0.05) across gender.

CONCLUSION

The hematological reference intervals established in this study showed a difference based on gender. We suggest preparing and using distinct local reference intervals for males and females separately.

The HIV paradox: perinatal mortality is lower in HIV+ mothers. A case-control study in Ethiopia

Background

In Ethiopia, HIV prevalence is 1.2% in 15-49-year-old women, peaking at 3% in aged 40-44. Nationally, efforts have made to provide HIV testing and treatment to all HIV+ subjects, and prevention of mother-to-child transmission. This may imply a closer monitor of health conditions for HIV+ pregnant women. Moreover, antenatal care (ANC) in the third trimester of pregnancy is associated with lower perinatal mortality (PNM). Considering this, we aimed at comparing PNM between HIV+ and HIV- mothers.

Methods

The study was conducted in Wolisso Hospital, Oromiya Region, Ethiopia, a second level hospital with a 1,000,000-catchment area. Cases were all mothers who experienced a perinatal death before hospital discharge. For each case, two mothers who gave birth to a baby alive until discharge were selected as controls. A regression model was built, considering maternal age, rural-urban residence, grand multiparity, twin pregnancy, maternal ongoing chronic/infectious disease and provision of ANC as potential confounders.

Results

Overall, 1175 cases and 2350 controls were included. HIV+ women (n = 71; 2,0%) showed a crude OR = 0.44 (95%CI: 0.24-0.81) for PNM and an adjusted aOR=0.50 (95%CI: 0.25-0.98) when controlling for the aforementioned confounders, including provision of ANC. While 69,0% of HIV+ women received specific ANC, only 24,2% of HIV- women did (p(χ2)&lt;0.001).

Conclusions

Our findings show how the risk of PNM is 50% less in HIV+ mothers. Because of their HIV-positive-status, they are more likely to be in contact with healthcare providers and, thus, to have higher chances to be addressed to ANC services. A large part of the contribution seems to reside in activities directly related to HIV control. This evidence supports national policies against HIV and suggests a considerable improvement of PNM by extending high quality ANC to all pregnant Ethiopian women. Paradoxically, HIV stands out for being a health threat that reduces PNM.

Key messages

In Wolisso hospital, a second level general hospital in Ethiopia, babies born to HIV+ women have a -50% risk of perinatal death. Extending high quality ANC is worth the effort: removing barriers to access and reaching all pregnant women would lead to a massive reduction in perinatal mortality.

Alteration of Clinical Chemistry Parameters Among Visceral Leishmaniasis Patients in Western Tigrai, Ethiopia, 2018/2019: A Comparative Cross-Sectional Study

BACKGROUND

Visceral leishmaniasis causes alterations of lipid metabolism and it is associated with hypocholesterolemia and severe hypertriglyceridemia. Hepatic dysfunction and life-threatening hepatitis are associated with visceral leishmaniasis. Kidney damage is frequently associated with increased morbidity and mortality in visceral leishmaniasis patients.

METHODS

A cross-sectional study was carried out to assess the alterations of clinical chemistry parameters among visceral leishmaniasis patients attending Kahsay Abera and Mearg hospitals, Northwest Ethiopia. A total of 100 visceral leishmaniasis patients and 100 healthy controls without visceral leishmaniasis were selected by using convenient sampling techniques. Data were entered and analyzed using statistical package for social sciences (SPSS) version 23.

RESULTS

Results were showed that the mean value of serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total bilirubin, and triglyceride was significantly higher in visceral leishmaniasis patients than in apparently healthy controls, but the mean value of serum urea and total cholesterol was significantly lower in visceral leishmaniasis patients than healthy controls.

CONCLUSION

The finding of this study concluded that visceral leishmaniasis causes significant alterations of clinical chemistry tests like liver and lipid profile tests compared to healthy controls.

Pregnancy suppresses Mycobacterium tuberculosis-specific Th1, but not Th2, cell-mediated functional immune responses during HIV/latent TB co-infection

Immunity to tuberculosis (TB) is suppressed due to HIV coinfection and this suppression could further be enhanced by pregnancy. However, the effect of pregnancy on Mycobacterium tuberculosis (M. tuberculosis)-specific immune response during HIV/latent TB co-infection is not well understood. Here we investigated the changes in M. tuberculosis-specific functional Th1, Th2 and antibody responses in pregnant women with HIV/latent TB co-Infection. Pregnancy, concurrent with HIV infection, triggers a substantial suppression of M. tuberculosis-specific IFN-γ responses in a CD4⁺ T cell count dependent manner with an insignificant change in IL-4 and IgG responses. Conversely, M. tuberculosis-specific IL-10 production was markedly augmented in latent TB infected pregnant women with a lesser extent during HIV co-infection. These findings reveal that pregnancy suppresses anti-mycobacterial protective immune response in a CD4⁺ T cell count dependent manner during HIV/latent TB co-infection, suggesting a higher risk of developing active TB during pregnancy as a result of failing to control TB infection.

Individual and household correlates of Helicobacter pylori infection among Young Ethiopian children in Ziway, Central Ethiopia

Background

Investigating distinct individual- and household-level risk factors for acquiring Helicobacter pylori (H. pylori) infection can inform disease prevention efforts and implicate possible routes of transmission. This study determined the magnitude of H. pylori infection among schoolchildren in Ziway, central Ethiopia and identified personal and household correlates of H. pylori infection in young Ethiopian children.

Methods

A total of 434 schoolchildren participated in this cross-sectional study. Infection status was assessed using antigen and antibody rapid tests. Demographic and lifestyle information was obtained from parents via an interviewer-led questionnaire. Univariate and multivariate logistic regressions were performed to assess the relationships between potential individual- and household-level risk factors and H. pylori infection.

Results

The prevalence of H. pylori infection was 65.7% (285/434). Of the personal variables assessed, the age group 10–14 years was found to be significantly associated with higher odds of H. pylori infection in univariate analysis (COR = 2.22, 95% CI: 1.06–4.66, p = 0.03) and remained positively correlated after adjusting for confounding factors. Of the household-level factors explored, having a traditional pit or no toilet was found to be significantly associated with 3.93-fold higher odds of H. pylori infection (AOR = 3.93, 95% CI: 1.51–10.3, p = 0.01), while the presence of smokers in the household was associated with 68% lower odds of infection (AOR = 0.32, 95% CI: 0.11–0.89, p = 0.03).

Conclusion

This study from a developing country provides additional evidence for older age as a personal risk factor for H. pylori infection and identifies correlations between socioeconomic and sanitation household factors and positive childhood infection status. The associations reported here support the hypothesized fecal-oralroute of transmission for H. pylori.

Community based reference interval of selected clinical chemistry parameters among apparently healthy Adolescents in Mekelle City, Tigrai, Northern Ethiopia

BACKGROUND

Locally established clinical laboratory reference intervals (RIs) are required to interpret laboratory test results for screening, diagnosis and prognosis. The objective of this study was establishing reference interval of clinical chemistry parameters among apparently healthy adolescents aged between 12 and 17 years in Mekelle, Tigrai, northern part of Ethiopia.

METHODS

Community based cross sectional study was employed from December 2018 to March 2019 in Mekelle city among 172 males and 172 females based on Multi stage sampling technique. Blood samples were tested for Fasting blood sugar (FBS), alanine aminino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), Creatinine, urea, total protein, albumin (ALB), direct and indirect bilirubin (BIL.D and BIL.T) using 25 Bio system clinical chemistry analyzer. Results were analyzed using SPSS version 23 software and based on the Clinical Laboratory Standard Institute (CLSI)/ International Federation of Clinical Chemistry (IFCC) C 28-A3 Guideline which defines the reference interval as the 95% central range of 2.5th and 97.5th percentiles. Mann Whitney U test, descriptive statistics and box and whisker were statistical tools used for analysis.

RESULTS

This study observed statistically significant differences between males and females in ALP, ALT, AST, Urea and Creatinine Reference intervals. The established reference intervals for males and females, respectively, were: ALP (U/L) 79.48-492.12 versus 63.56-253.34, ALT (U/L) 4.54-23.69 versus 5.1-20.03, AST 15.7-39.1 versus 13.3-28.5, Urea (mg/dL) 9.33-24.99 versus 7.43-23.11, and Creatinine (mg/dL) 0.393-0.957 versus 0.301-0.846. The combined RIs for Total Protein (g/dL) was 6.08-7.85, ALB (g/dL) 4.42-5.46, FBS(mg/dL) 65-110, BIL.D (mg/dL) 0.033-0.532, and BIL.T (mg/dL) 0.106-0.812.

CONCLUSIONS

The result showed marked difference among sex and with the company derived values for selected clinical chemistry parameters. Thus, use of age and sex specific locally established reference intervals for clinical chemistry parameters is recommended.

Human Monocytes/Macrophage Inflammatory Cytokine Changes Following in vivo and in vitro Schistomam manoni Infection

Introduction

Epidemiological and animal studies indicate that helminth infections have positive effects due to their potential to protect against autoimmune diseases. Here, we aim to assess the effect of S. mansoni infection on immune modulation of human monocytes and their potential protection against autoimmune disease development both in vivo and in vitro.

Materials and Methods

Monocytes were isolated from helminth-infected Ethiopians (MHIE), and from Dutch healthy volunteers (MHV). The MHV were stimulated in vitro with S. mansoni soluble egg antigens (SEA) or soluble worm antigens (SWA). In addition, phenotypical changes were studied directly, as well as after culturing for 6 days in the presence of human serum to obtain macrophages. Q-PCR, flow cytometry, multiplex bead immunoassay, and live-cell imaging were employed during analysis.

Results

MHIE showed elevated transcripts of SOCS-1 and TNF-α compared to MHV. Similarly, MHV that were stimulated with SEA demonstrated enhanced levels of SOCS-1, IL-10, and IL-12 mRNA, compared to control MHV. Remarkably, the SEA-treated monocytes showed a much higher motility than control monocytes, a hallmark of a patrolling phenotype. Furthermore, in vitro cultured macrophages that were stimulated by SEA exhibited enhanced mRNA levels of SOCS-1, IL-10, TNF-α, IL-12 and TGF-β, compared to control macrophages.

Conclusion

Macrophages from MHIE as well as SEA-treated MHV show an intermediate activation phenotype with both pro-inflammatory and anti-inflammatory characteristics in vitro. The observed pro-inflammatory properties might reflect a recent response of the cells due to contact with a pathogen, whereas the anti-inflammatory properties might contribute to helminth-induced protection against inflammatory diseases. Large-scale study is recommended to consolidate the findings of the present study.

Point your SmartPhone at the code above. If you have a QR code reader the video abstract will appear. Or use:

https://youtu.be/SYOVExqwTRU

Role of platelet parameters in early detection and prediction of severity of preeclampsia: A comparative cross-sectional study at Ayder comprehensive specialized and Mekelle general hospitals, Mekelle, Tigray, Ethiopia

BACKGROUND

Platelet parameters alterations are one of the most commonly identified hematological changes in preeclampsia (PE). However, their functions as a tool for prediction and prognosis of PE have not been extensively studied in developing countries. The aim of this study was to compare platelet count (PC), and platelet indices (mean platelet volume (MPV), platelet distribution width (PDW), and platelet large cell ratio (PLCR)) between preeclamptic and normotensive (NT) pregnant women and assess their role in diagnosis and prediction of PE development.

METHODS

A cross sectional comparative study was conducted at Ayder comprehensive specialized hospital (ACSH) and Mekelle general hospital (MGH) from January to March 2017. Platelet parameters of mild preeclamptic (mPE) (n = 35), severe preeclamptic (sPE) (n = 44) and NT pregnant women (n = 140) were analyzed using SYSMEX-XT 4000i automated hematology analyzer. One-way ANOVA supplemented with post-hoc test, receiver operating characteristics (ROC) curve and pearson correlation test statistical analyses were performed. P < 0.05 was considered significant.

RESULT

Pregnant women with sPE had lower PC as compared with that of mPE and NT women (p<0.05). All platelet indices showed significant increment with severity of PE. PC was negatively correlated with platelet indices. There was a positive correlation among platelet indices. ROC analysis revealed that MPV had the largest area under the ROC curve (0.85; 95%CI (0.79, 0.89)) with cutoff value >9.45fl, sensitivity of 83.5%, specificity of 86.4%, positive predictive value of 77.6% and negative predictive value of 90.3%.

CONCLUSION

MPV and PC were identified as good candidates for sPE diagnosis. Because evaluation of platelet parameters is rapid, reliable and economical, they can be utilized as an alternative biomarker for prediction and prognosis of PE.