HIV prevalence and awareness among adults presenting for enrolment into a study of people at risk for HIV in Kisumu County, Western Kenya

INTRODUCTION

Despite declines in new HIV diagnoses both globally and in Kenya, parts of Western Kenya still report high HIV prevalence and incidence. We evaluated HIV prevalence to inform the development of policies for strategic and targeted HIV prevention interventions.

METHODS

Adult participants aged 18-35 years were recruited in Kisumu County and screened for HIV for a prospective HIV incidence cohort. Questionnaires assessed HIV-associated risk behaviors. Participants who tested positive for HIV were disaggregated into groups based on prior knowledge of their HIV status: previously-diagnosed and newly-diagnosed. In separate analyses by prior knowledge, robust Poisson regression was used to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for factors potentially associated with a positive HIV test in each group, as compared to participants without HIV.

RESULTS

Of 1059 participants tested for HIV, 196 (18.5%) had a positive HIV test. Among PLWH, 78 (39.8%) were newly diagnosed with HIV at screening. After adjusting for other variables, previously-diagnosed HIV was more common among females than males (PR 2.70, 95%CI 1.69-4.28), but there was no observed sex difference in newly-diagnosed HIV prevalence (PR 1.05, 95%CI 0.65-1.69). Previously-diagnosed HIV was also more common among people reporting consistent use of condoms with primary sexual partners as compared to inconsistent condom use (PR 3.19, 95%CI 2.09-4.86), but newly-diagnosed HIV was not associated with such a difference between consistent and inconsistent condom use (PR 0.73, 95%CI 0.25-2.10).

CONCLUSION

Prevalence of newly-diagnosed HIV was high, at approximately 8% of participants, and not statistically different between genders, highlighting the need for improved HIV case finding regardless of sex. The higher prevalence of previously-diagnosed HIV in female participants may reflect higher rates of HIV testing through more encounters with the healthcare system. Higher prevalence of consistent condom use amongst those previously-diagnosed suggests behavioral change to reduce HIV transmission, a potential benefit of policies to facilitate earlier HIV diagnosis.

Early sexual debut is associated with drug use and decreased educational attainment among males and females in Kisumu County, Kenya

Differing global sociocultural contexts of sexual relationships influence age at first sexual intercourse with potentially long-lasting region-specific effects such as increased risk of contracting HIV and other sexually transmitted infections (STIs). In these cross-sectional analyses of data from the screening and enrollment visits for an HIV incidence study in Kisumu County, Kenya, we evaluated factors associated with having experienced an early sexual debut (ESD) among males and females aged 18-35 years. Clinical evaluation was performed and sexual behaviors were assessed via questionnaire. ESD was defined as self-reported age 15 years or younger at first sexual intercourse. Robust Poisson regression was used to estimate prevalence ratios (PRs) and 95% confidence intervals (95% CIs) for factors associated with ESD. Of 1057 participants, 542 (51.3%) were female. Participants' median age at study screening was 25 years (interquartile range [IQR]: 22-29), and at sexual debut was 16 years (IQR: 14-17). Five hundred and four participants (47.7%) reported ESD. ESD was less common among females (PR 0.78, CI 0.67-0.90) and participants with more than primary education (PR 0.56, CI 0.47-0.66). ESD was more common in participants with a history of drug use (PR 1.28, CI 1.10-1.49). Drug use removed the protective effect of education (some secondary education or less, no drug use: PR 0.72, CI 0.61-0.85; some secondary education or less, drug use: PR 0.94, CI 0.74-1.18). ESD was common in our study and associated with lower educational attainment and increased likelihood of drug use. Interventions are needed early in life, well before 15 years of age, to encourage engagement in schooling and prevent drug use. Comprehensive sexual education and interventions to prevent drug use may be beneficial before the age of 15 years.

Epidemiological and clinical implications of asymptomatic malaria and schistosomiasis co-infections in a rural community in western Kenya

BACKGROUND

Malaria and schistosomiasis present considerable disease burden in tropical and sub-tropical areas and severity is worsened by co-infections in areas where both diseases are endemic. Although pathogenesis of these infections separately is well studied, there is limited information on the pathogenic disease mechanisms and clinical disease outcomes in co-infections. In this study, we investigated the prevalence of malaria and schistosomiasis co-infections, and the hematologic and blood chemistry abnormalities in asymptomatic adults in a rural fishing community in western Kenya.

METHODS

This sub-study used samples and data collected at enrollment from a prospective observational cohort study (RV393) conducted in Kisumu County, Kenya. The presence of malaria parasites was determined using microscopy and real-time-PCR, and schistosomiasis infection by urine antigen analysis (CCA). Hematological analysis and blood chemistries were performed using standard methods. Statistical analyses were performed to compare demographic and infection data distribution, and hematologic and blood chemistry parameters based on different groups of infection categories. Clinically relevant hematologic conditions were analyzed using general linear and multivariable Poisson regression models.

RESULTS

From February 2017 to May 2018, we enrolled 671 participants. The prevalence of asymptomatic Plasmodium falciparum was 28.2% (157/556) and schistosomiasis 41.2% (229/562), with 18.0% (100/556) of participants co-infected. When we analyzed hematological parameters using Wilcoxon rank sum test to evaluate median (IQR) distribution based on malarial parasites and/or schistosomiasis infection status, there were significant differences in platelet counts (p = 0.0002), percent neutrophils, monocytes, eosinophils, and basophils (p < 0.0001 each). Amongst clinically relevant hematological abnormalities, eosinophilia was the most prevalent at 20.6% (116/562), whereas thrombocytopenia was the least prevalent at 4.3% (24/562). In univariate model, Chi-Square test performed for independence between participant distribution in different malaria parasitemia/schistosomiasis infection categories within each clinical hematological condition revealed significant differences for thrombocytopenia and eosinophilia (p = 0.006 and p < 0.0001, respectively), which was confirmed in multivariable models. Analysis of the pairwise mean differences of liver enzyme (ALT) and kidney function (Creatinine Clearance) indicated the presence of significant differences in ALT across the infection groups (parasite + /CCA + vs all other groups p < .003), but no differences in mean Creatinine Clearance across the infection groups.

CONCLUSIONS

Our study demonstrates the high burden of asymptomatic malaria parasitemia and schistosomiasis infection in this rural population in Western Kenya. Asymptomatic infection with malaria or schistosomiasis was associated with laboratory abnormalities including neutropenia, leukopenia and thrombocytopenia. These abnormalities could be erroneously attributed to other diseases processes during evaluation of diseases processes. Therefore, evaluating for co-infections is key when assessing individuals with laboratory abnormalities. Additionally, asymptomatic infection needs to be considered in control and elimination programs given high prevalence documented here.

Clinical laboratory reference values in adults in Kisumu County, Western Kenya; hematology, chemistry and CD4

Background

Clinical laboratory reference intervals (RIs) are essential for diagnosing and managing patients in routine clinical care as well as establishing eligibility criteria and defining adverse events in clinical trials, but may vary by age, gender, genetics, nutrition and geographic location. It is, therefore, critical to establish region-specific reference values in order to inform clinical decision-making.

Methods

We analyzed data from a prospective observational HIV incidence cohort study in Kombewa, Kenya. Study participants were healthy males and females, aged 18–35 years, without HIV. Median and 95% reference values (2.5^th percentile to 97.5^th percentile) were calculated for laboratory parameters including hematology, chemistry studies, and CD4 T cell count. Standard Deviation Ratios (SDR) and Bias Ratios (BR) are presented as measures of effect magnitude. Findings were compared with those from the United States and other Kenyan studies.

Results

A total of 299 participants were analyzed with a median age of 24 years (interquartile range: 21–28). Ratio of males to females was 0.9:1. Hemoglobin range (2.5^th—97.5^th percentiles) was 12.0–17.9 g/dL and 9.5–15.3 g/dL in men and women respectively. In the cohort, MCV range was 59-95fL, WBC 3.7–9.2×10³/μL, and platelet 154–401×10³/μL. Chemistry values were higher in males; the creatinine RI was 59–103 μmol/L in males vs. 46–76 μmol/L in females (BRUL>.3); and the alanine transferase range was 8.8–45.3 U/L in males vs. 7.5–36.8 U/L in females (SDR>.3). The overall CD4 T cell count RI was 491–1381 cells/μL. Some parameters including hemoglobin, neutrophil, creatinine and ALT varied with that from prior studies in Kenya and the US.

Conclusion

This study not only provides clinical reference intervals for a population in Kisumu County but also highlights the variations in comparable settings, accentuating the requirement for region-specific reference values to improve patient care, scientific validity, and quality of clinical trials in Africa.

Surveillance for respiratory health care-associated infections among inpatients in 3 Kenyan hospitals, 2010-2012

BACKGROUND

Although health care-associated infections are an important cause of morbidity and mortality worldwide, the epidemiology and etiology of respiratory health care-associated infections (rHAIs) have not been documented in Kenya. In 2010, the Ministry of Health, Kenya Medical Research Institute, and Centers for Disease Control and Prevention initiated surveillance for rHAIs at 3 hospitals.

METHODS

At each hospital, we surveyed intensive care units (ICUs), pediatric wards, and medical wards to identify patients with rHAIs, defined as any hospital-onset (≥3 days after admission) fever (≥38°C) or hypothermia (<35°C) with concurrent signs or symptoms of acute respiratory infection. Nasopharyngeal and oropharyngeal specimens were collected from these patients and tested by real-time reverse transcription polymerase chain reaction for influenza and 7 other viruses.

RESULTS

From April 2010-September 2012, of the 379 rHAI cases, 60.7% were men and 57.3% were children <18 years old. The overall incidence of rHAIs was 9.2 per 10,000 patient days, with the highest incidence in the ICUs. Of all specimens analyzed, 45.7% had at least 1 respiratory virus detected; 92.2% of all positive viral specimens were identified in patients <18 years old.

CONCLUSION

We identified rHAIs in all ward types under surveillance in Kenyan hospitals. Viruses may have a substantial role in these infections, particularly among pediatric populations. Further research is needed to refine case definitions and understand rHAIs in ICUs.

Impact of expanded antiretroviral use on incidence and prevalence of tuberculosis in children with HIV in Kenya

SETTING

Antiretroviral therapy (ART) reduces pulmonary tuberculosis (PTB) in human immunodeficiency virus (HIV) infected children. Recent ART recommendations have increased the number of children on ART.

OBJECTIVE

To determine the prevalence and incidence of TB in HIV-infected children after the implementation of expanded ART guidelines.

DESIGN

A prospective cohort study including HIV-infected children aged 6 weeks to 14 years was conducted in Kenya. The primary outcome measure was clinically diagnosed TB. Study participants were screened for prevalent TB at enrollment using Kenya's national guidelines and followed at monthly intervals to detect incident TB. Predictors of TB were assessed using logistic regression and Cox proportional hazards regression.

RESULTS

Of 689 participants (median age 6.4 years), 509 (73.9%) were on ART at baseline. There were 51 cases of prevalent TB (7.4%) and 10 incident cases, with over 720.3 child-years of observation (incidence 1.4 per 100 child-years). Months on ART (adjusted hazard ratio [aHR] 0.91, P = 0.003; aOR 0.91, P< 0.001) and months in care before ART (aHR 0.87, P= 0.001; aOR 0.92, P < 0.001) were protective against incident and prevalent TB.

CONCLUSIONS

ART was protective against TB in this cohort of HIV-infected children with high levels of ART use. Optimal TB prevention strategies should emphasize early ART in children.

Seroprevalence of hepatitis B markers in pregnant women in Kenya

OBJECTIVE

To evaluate hepatitis B serological markers in pregnant women from various geographical sites in Kenya.

DESIGN

A cross-sectional observational study of women attending antenatal clinics.

SETTING

The Kenyatta National Hospital and eight hospitals from five provinces in Kenya.

SUBJECTS

All women in their third trimester of pregnancy attending the antenatal clinic over the period June 2001 to June 2002.

MAIN OUTCOME MEASURES

For each pregnant woman age and gestation were documented. Hepatitis serological markers were evaluated.

RESULTS

A total of 2241 pregnant women were enrolled. Among them 205 women (9.3%) were positive for HbsAg and from these 18 (8.8%) were found to have HbeAg. Protective antibodies (anti-HbsAg) were detected in 669 (30.2%) of the women. There were notable significant regional differences for HbsAg rates.

CONCLUSIONS

These results confirm the presence of high disease carrier rate and the corresponding previously reported low level of HbeAg suggesting questionable low rate of perinatal transmission but high rate of horizontal transmission.

Assessment of potential indicators for protein-energy malnutrition in the algorithm for integrated management of childhood illness

Potential indicators were assessed for the two classifications of protein-energy malnutrition in the guidelines for integrated management of childhood illness: severe malnutrition, which requires immediate referral to hospital, and very low weight, which calls for feeding assessment, nutritional counselling and follow-up. Children aged < 2 years require feeding assessment and counselling as a preventive intervention. For severe malnutrition, we examined 1202 children admitted to a Kenyan hospital for any association of the indicators with mortality within one month. Bipedal oedema indicating kwashiorkor, and two marasmus indicators (visible severe wasting and weight-for-height (WFH) Z-score of < -3) were associated with a significantly increased mortality risk (odds ratios, 3.1-3.9). Very low weight-for-age (WFA) (Z-score of < -4.4) was not associated with an increased risk of mortality. Because first-level health facilities generally lack length-boards, bipedal oedema and visible severe wasting were chosen as indicators of severe malnutrition. To assess potential WFA thresholds for the very low weight classification, our primary source of data came from 1785 Kenyan outpatient children, but we also examined data from surveys in Nepal, Bolivia, and Togo. We examined the performance of WFA at various thresholds to identify children with low WFH and, for children aged < or = 2 years, low height-for-age (HFA). Use of a WFA threshold Z-score of < -2 identified a considerable proportion of children (from 13% in Bolivia to 68% in Nepal) which, in most settings, would pose an enormous burden on the health facility. Among ill children in Kenya, a threshold WFA Z-score of < -3 had a sensitivity of 89-100% to detect children with WFH Z-scores of < -3, and, with an identification rate of 9%, would avoid overburdening the clinics. Potential modifications include use of a more restrictive cut-off in countries with high rates of stunting, or the elimination of the WFA screen in order to concentrate efforts on intervention for all children below the 2-year age cut-off. Key issues in every country include the capacity to provide counselling for many children and linkage to nutritional improvement programmes in the community.

Clinical signs for the recognition of children with moderate or severe anaemia in western Kenya

Optimal treatment of Plasmodium falciparum-related paediatric anaemia can result in improved haematological recovery and survival. Clinical predictors are needed to identify children with anaemia in settings where laboratory measurements are not available. The use of conjunctival (eyelid), palmar, nailbed, and tongue pallor to detect children with moderate anaemia (haemoglobin, 5.0-7.9 g/dl) or severe anaemia (haemoglobin, < 5.0 g/dl) was evaluated among children seen at an outpatient and inpatient setting in a hospital in western Kenya. Severe nailbed or severe palmar pallor had the highest sensitivity (62% and 60%, resp.), compared with severe conjunctival pallor (sensitivity = 31%), to detect children with severe anaemia in the outpatient setting. Children with moderate anaemia were best identified by the presence of nailbed or palmar pallor (sensitivity = 90% for both signs), compared with conjunctival pallor (sensitivity = 81%). Clinical signs of respiratory distress, in addition to the presence of severe pallor, did not increase the recognition of children requiring hospitalization for severe anaemia. Among inpatients, the sensitivity of severe nailbed pallor (59%) was highest for detecting children with severe anaemia, although the sensitivity of severe conjunctival pallor and severe palmar pallor was the same (53% for both signs). Presence of conjunctival pallor (sensitivity = 74%) was similar in sensitivity to both nailbed and palmar pallor (70% for both signs) among children with moderate anaemia. The sensitivity of tongue pallor was low among all children evaluated. Low haemoglobin levels were significantly associated with the likelihood of being smear-positive for P. falciparum. This study demonstrates that clinical criteria can be used to identify children with moderate and severe anaemia, thus enabling implementation of treatment algorithms. Children aged < 36 months who live in an area with P. falciparum malaria should receive treatment with an effective antimalarial drug if they have pallor.

Evaluation of an algorithm for integrated management of childhood illness in an area of Kenya with high malaria transmission

In 1993, the World Health Organization completed the development of a draft algorithm for the integrated management of childhood illness (IMCI), which deals with acute respiratory infections, diarrhoea, malaria, measles, ear infections, malnutrition, and immunization status. The present study compares the performance of a minimally trained health worker to make a correct diagnosis using the draft IMCI algorithm with that of a fully trained paediatrician who had laboratory and radiological support. During the 14-month study period, 1795 children aged between 2 months and 5 years were enrolled from the outpatient paediatric clinic of Siaya District Hospital in western Kenya; 48% were female and the median age was 13 months. Fever, cough and diarrhoea were the most common chief complaints presented by 907 (51%), 395 (22%), and 199 (11%) of the children, respectively; 86% of the chief complaints were directly addressed by the IMCI algorithm. A total of 1210 children (67%) had Plasmodium falciparum infection and 1432 (80%) met the WHO definition for anaemia (haemoglobin < 11 g/dl). The sensitivities and specificities for classification of illness by the health worker using the IMCI algorithm compared to diagnosis by the physician were: pneumonia (97% sensitivity, 49% specificity); dehydration in children with diarrhoea (51%, 98%); malaria (100%, 0%); ear problem (98%, 2%); nutritional status (96%, 66%); and need for referral (42%, 94%). Detection of fever by laying a hand on the forehead was both sensitive and specific (91%, 77%). There was substantial clinical overlap between pneumonia and malaria (n = 895), and between malaria and malnutrition (n = 811). Based on the initial analysis of these data, some changes were made in the IMCI algorithm. This study provides important technical validation of the IMCI algorithm, but the performance of health workers should be monitored during the early part of their IMCI training.