Trends observed during a decade of paediatric sick visits to peripheral health facilities in rural western Kenya, 1997-2006

Prevalence of Selected Zoonotic Diseases and Risk Factors at a Human-Wildlife-Livestock Interface in Mpumalanga Province, South Africa

A lack of surveillance and diagnostics for zoonotic diseases in rural human clinics limits clinical awareness of these diseases. We assessed the prevalence of nine zoonotic pathogens in a pastoral, low-income, HIV-endemic community bordering wildlife reserves in South Africa. Two groups of participants were included: malaria-negative acute febrile illness (AFI) patients, called febrilers, at three clinics (n = 74) and second, farmers, herders, and veterinary staff found at five government cattle dip-tanks, called dip-tanksters (n = 64). Blood samples were tested using one PCR (Bartonella spp.) and eight antibody-ELISAs, and questionnaires were conducted to assess risk factors. Seventy-seven percent of febrilers and 98% of dip-tanksters had at least one positive test. Bartonella spp. (PCR 9.5%), spotted fever group (SFG) Rickettsia spp. (IgM 24.1%), Coxiella burnetii. (IgM 2.3%), and Leptospira spp. (IgM 6.8%) were present in febrilers and could have been the cause of their fever. Dip-tanksters and febrilers had evidence of past infection to Rickettsia spp. (IgG 92.2% and 63.4%, respectively) and C. burnetii (IgG 60.9% and 37.8%, respectively). No Brucella infection or current Bartonella infection was found in the dip-tanksters, although they had higher levels of recent exposure to Leptospira spp. (IgM 21.9%) compared to the febrilers. Low levels of West Nile and Sindbis, and no Rift Valley fever virus exposure were found in either groups. The only risk factor found to be significant was attending dip-tanks in febrilers for Q fever (p = 0.007). Amoxicillin is the local standard treatment for AFI, but would not be effective for Bartonella spp. infections, SFG rickettsiosis, Q fever infections, or the viral infections. There is a need to revise AFI treatment algorithms, educate medical and veterinary staff about these pathogens, especially SFG rickettsiosis and Q fever, support disease surveillance systems, and inform the population about reducing tick and surface water contact.

Antibiotic Utilization and the Role of Suspected and Diagnosed Mosquito-borne Illness Among Adults and Children With Acute Febrile Illness in Pune, India

Background

Antibiotic resistance mechanisms originating in low- and middle- income countries are among the most common worldwide. Reducing unnecessary antibiotic use in India, the world's largest antibiotic consumer, is crucial to control antimicrobial resistance globally. Limited data describing factors influencing Indian clinicians to start or stop antibiotics are available.

Methods

Febrile adults and children admitted to a public tertiary care hospital in Pune, India, were enrolled. Antibiotic usage and clinical history were recorded. Immunoassays for mosquito-borne disease and bacterial cultures were performed by protocol and clinician-directed testing. Clinical factors were assessed for association with empiric antibiotic initiation and discontinuation by day 5 using multivariable logistic regression and propensity score-matched Cox proportional hazard models.

Results

Among 1486 participants, 683 (82%) adults and 614 (94%) children received empiric antibiotics. Participants suspected of having mosquito-borne disease were less likely to receive empiric antibiotics (adjusted odds ratio [AOR], 0.5; 95% confidence interval [CI], .4-.8). Empiric antibiotics were discontinued in 450 (35%) participants by day 5. Dengue or malaria testing performed before day 4 was positive in 162 (12%) participants, and was associated with antibiotic discontinuation (AOR, 1.7; 95% CI, 1.2-2.4). In a propensity score-matched model accounting for admission suspicion of mosquito-borne disease, positive dengue or malaria tests increased hazard of antibiotic discontinuation (hazard ratio, 1.6; 95% CI, 1.2-2.0).

Conclusions

Most patients with acute febrile illness in an Indian public hospital setting receive empiric antibiotics. Mosquito-borne disease identification is associated with reduced empiric antibiotic use and faster antibiotic discontinuation.

Reducing Uncertainty for Acute Febrile Illness in Resource-Limited Settings: The Current Diagnostic Landscape

AbstractDiagnosing the cause of acute febrile illness in resource-limited settings is important-to give the correct antimicrobials to patients who need them, to prevent unnecessary antimicrobial use, to detect emerging infectious diseases early, and to guide vaccine deployment. A variety of approaches are yielding more rapid and accurate tests that can detect more pathogens in a wider variety of settings. After decades of slow progress in diagnostics for acute febrile illness in resource-limited settings, a wave of converging advancements will enable clinicians in resource-limited settings to reduce uncertainty for the diagnosis of acute febrile illness.

Managing the Sick Child in the Era of Declining Malaria Transmission: Development of ALMANACH, an Electronic Algorithm for Appropriate Use of Antimicrobials

OBJECTIVE

To review the available knowledge on epidemiology and diagnoses of acute infections in children aged 2 to 59 months in primary care setting and develop an electronic algorithm for the Integrated Management of Childhood Illness to reach optimal clinical outcome and rational use of medicines.

METHODS

A structured literature review in Medline, Embase and the Cochrane Database of Systematic Review (CDRS) looked for available estimations of diseases prevalence in outpatients aged 2-59 months, and for available evidence on i) accuracy of clinical predictors, and ii) performance of point-of-care tests for targeted diseases. A new algorithm for the management of childhood illness (ALMANACH) was designed based on evidence retrieved and results of a study on etiologies of fever in Tanzanian children outpatients.

FINDINGS

The major changes in ALMANACH compared to IMCI (2008 version) are the following: i) assessment of 10 danger signs, ii) classification of non-severe children into febrile and non-febrile illness, the latter receiving no antibiotics, iii) classification of pneumonia based on a respiratory rate threshold of 50 assessed twice for febrile children 12-59 months; iv) malaria rapid diagnostic test performed for all febrile children. In the absence of identified source of fever at the end of the assessment, v) urine dipstick performed for febrile children <2 years to consider urinary tract infection, vi) classification of 'possible typhoid' for febrile children >2 years with abdominal tenderness; and lastly vii) classification of 'likely viral infection' in case of negative results.

CONCLUSION

This smartphone-run algorithm based on new evidence and two point-of-care tests should improve the quality of care of <5 year children and lead to more rational use of antimicrobials.

Clinical features for diagnosis of pneumonia in children younger than 5 years: a systematic review and meta-analysis

BACKGROUND

Pneumonia is the biggest cause of deaths in young children in developing countries, but early diagnosis and intervention can effectively reduce mortality. We aimed to assess the diagnostic value of clinical signs and symptoms to identify radiological pneumonia in children younger than 5 years and to review the accuracy of WHO criteria for diagnosis of clinical pneumonia.

METHODS

We searched Medline (PubMed), Embase (Ovid), the Cochrane Database of Systematic Reviews, and reference lists of relevant studies, without date restrictions, to identify articles assessing clinical predictors of radiological pneumonia in children. Selection was based on: design (diagnostic accuracy studies), target disease (pneumonia), participants (children aged <5 years), setting (ambulatory or hospital care), index test (clinical features), and reference standard (chest radiography). Quality assessment was based on the 2011 Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. For each index test, we calculated sensitivity and specificity and, when the tests were assessed in four or more studies, calculated pooled estimates with use of bivariate model and hierarchical summary receiver operation characteristics plots for meta-analysis.

FINDINGS

We included 18 articles in our analysis. WHO-approved signs age-related fast breathing (six studies; pooled sensitivity 0·62, 95% CI 0·26-0·89; specificity 0·59, 0·29-0·84) and lower chest wall indrawing (four studies; 0·48, 0·16-0·82; 0·72, 0·47-0·89) showed poor diagnostic performance in the meta-analysis. Features with the highest pooled positive likelihood ratios were respiratory rate higher than 50 breaths per min (1·90, 1·45-2·48), grunting (1·78, 1·10-2·88), chest indrawing (1·76, 0·86-3·58), and nasal flaring (1·75, 1·20-2·56). Features with the lowest pooled negative likelihood ratio were cough (0·30, 0·09-0·96), history of fever (0·53, 0·41-0·69), and respiratory rate higher than 40 breaths per min (0·43, 0·23-0·83).

INTERPRETATION

Not one clinical feature was sufficient to diagnose pneumonia definitively. Combination of clinical features in a decision tree might improve diagnostic performance, but the addition of new point-of-care tests for diagnosis of bacterial pneumonia would help to attain an acceptable level of accuracy.

FUNDING

Swiss National Science Foundation.

Repeated mass distributions and continuous distribution of long-lasting insecticidal nets: modelling sustainability of health benefits from mosquito nets, depending on case management

Background

Stagnating funds for malaria control have spurred interest in the question of how to sustain the gains of recent successes with long-lasting insecticidal nets (LLINs) and improved case management (CM). This simulation study examined the malaria transmission and disease dynamics in scenarios with sustained LLINs and CM interventions and tried to determine optimal LLIN distribution rates. The effects of abruptly halting LLIN distribution were also examined.

Methods

Dynamic simulations of malaria in humans and mosquitoes were run on the OpenMalaria platform, using stochastic individual-based simulation models. LLINs were distributed in a range of transmission settings, with varying CM coverage levels.

Results

In the short-term, LLINs were beneficial over the entire transmission spectrum, reducing both transmission and disease burden. In the long-term, repeated distributions sustainably reduced transmission in all settings. However, because of the resulting reduction in acquired immunity in the population, the malaria disease burden, after initially being reduced, gradually increased and eventually stabilized at a new level. This new level was higher than the pre-intervention level in previously high transmission settings, if there is a maximum disease burden in the relationship between transmission and disease burden at intermediate transmission levels. This result could lead one to conclude that sustained LLIN distribution might not be cost-effective in high transmission settings in the long term. However, improved CM rendered LLINs more cost-effective in higher transmission settings than in those without improved CM and the majority of the African population lives in areas where CM and LLINs are sustainably combined. The effects of changes in LLIN distribution rate on cost-effectiveness were relatively small compared to the effects of changes in transmission setting and CM. Abruptly halting LLIN distribution led to temporary morbidity peaks, which were particularly large in low to intermediate transmission settings.

Conclusions

This study reaffirms the importance of context specific intervention planning. Intervention planning must include combinations of malaria vector control and CM, and must consider both the pre-intervention transmission level and the intervention history to account for the loss of immunity and the potential for rebounds in disease burden.

Local use of geographic information systems to improve data utilisation and health services: mapping caesarean section coverage in rural Rwanda

OBJECTIVES

To show the utility of combining routinely collected data with geographic location using a Geographic Information System (GIS) in order to facilitate a data-driven approach to identifying potential gaps in access to emergency obstetric care within a rural Rwandan health district.

METHODS

Total expected births in 2009 at sub-district levels were estimated using community health worker collected population data. Clinical data were extracted from birth registries at eight health centres (HCs) and the district hospital (DH). C-section rates as a proportion of total expected births were mapped by cell. Peri-partum foetal mortality rates per facility-based births, as well as the rate of uterine rupture as an indication for C-section, were compared between areas of low and high C-section rates.

RESULTS

The lowest C-section rates were found in the more remote part of the hospital catchment area. The sector with significantly lower C-section rates had significantly higher facility-based peri-partum foetal mortality and incidence of uterine rupture than the sector with the highest C-section rates (P < 0.034).

CONCLUSIONS

This simple approach for geographic monitoring and evaluation leveraging existing health service and GIS data facilitated evidence-based decision making and represents a feasible approach to further strengthen local data-driven decisions for resource allocation and quality improvement.

Influenza and malaria coinfection among young children in western Kenya, 2009-2011

BACKGROUND

Although children <5 years old in sub-Saharan Africa are vulnerable to both malaria and influenza, little is known about coinfection.

METHODS

This retrospective, cross-sectional study in rural western Kenya examined outpatient visits and hospitalizations associated with febrile acute respiratory illness (ARI) during a 2-year period (July 2009-June 2011) in children <5 years old.

RESULTS

Across sites, 45% (149/331) of influenza-positive patients were coinfected with malaria, whereas only 6% (149/2408) of malaria-positive patients were coinfected with influenza. Depending on age, coinfection was present in 4%-8% of outpatient visits and 1%-3% of inpatient admissions for febrile ARI. Children with influenza were less likely than those without to have malaria (risk ratio [RR], 0.57-0.76 across sites and ages), and children with malaria were less likely than those without to have influenza (RR, 0.36-0.63). Among coinfected children aged 24-59 months, hospital length of stay was 2.7 and 2.8 days longer than influenza-only-infected children at the 2 sites, and 1.3 and 3.1 days longer than those with malaria only (all P < .01).

CONCLUSIONS

Coinfection with malaria and influenza was uncommon but associated with longer hospitalization than single infections among children 24-59 months of age.

Impact of implementation of free high-quality health care on health facility attendance by sick children in rural western Kenya

OBJECTIVES

To explore whether implementation of free high-quality care as part of research programmes resulted in greater health facility attendance by sick children.

METHODS

As part of the Intermittent Preventive Treatment for Malaria in Infants (IPTi), begun in 2004, and population-based infectious disease surveillance (PBIDS), begun in 2005 in Asembo, rural western Kenya, free high-quality care was offered to infants and persons of all ages, respectively, at one Asembo facility, Lwak Hospital. We compared rates of sick-child visits by children <10 years to all seven Asembo clinics before and after implementation of free high-quality care in 10 intervention villages closest to Lwak Hospital and 8 nearby comparison villages not participating in the studies. Incidence rates and rate ratios for sick-child visits were compared between intervention and comparison villages by time period using Poisson regression.

RESULTS

After IPTi began, the rate of sick-child visits for infants, the study's target group, in intervention villages increased by 191% (95% CI 75-384) more than in comparison villages, but did not increase significantly more in older children. After PBIDS began, the rate of sick-child visits in intervention villages increased by 267% (95% CI 76-661) more than that in comparison villages for all children <10 years. The greatest increases in visit rates in intervention villages occurred 3-6 months after the intervention started. Visits for cough showed greater increases than visits for fever or diarrhoea.

CONCLUSIONS

Implementation of free high-quality care increased healthcare use by sick children. Cost and quality of care are potentially modifiable barriers to improving access to care in rural Africa.

The burden of common infectious disease syndromes at the clinic and household level from population-based surveillance in rural and urban Kenya

BACKGROUND

Characterizing infectious disease burden in Africa is important for prioritizing and targeting limited resources for curative and preventive services and monitoring the impact of interventions.

METHODS

From June 1, 2006 to May 31, 2008, we estimated rates of acute lower respiratory tract illness (ALRI), diarrhea and acute febrile illness (AFI) among >50,000 persons participating in population-based surveillance in impoverished, rural western Kenya (Asembo) and an informal settlement in Nairobi, Kenya (Kibera). Field workers visited households every two weeks, collecting recent illness information and performing limited exams. Participants could access free high-quality care in a designated referral clinic in each site. Incidence and longitudinal prevalence were calculated and compared using Poisson regression.

RESULTS

INCIDENCE RATES RESULTING IN CLINIC VISITATION WERE THE FOLLOWING: ALRI--0.36 and 0.51 episodes per year for children <5 years and 0.067 and 0.026 for persons ≥ 5 years in Asembo and Kibera, respectively; diarrhea--0.40 and 0.71 episodes per year for children <5 years and 0.09 and 0.062 for persons ≥ 5 years in Asembo and Kibera, respectively; AFI--0.17 and 0.09 episodes per year for children <5 years and 0.03 and 0.015 for persons ≥ 5 years in Asembo and Kibera, respectively. Annually, based on household visits, children <5 years in Asembo and Kibera had 60 and 27 cough days, 10 and 8 diarrhea days, and 37 and 11 fever days, respectively. Household-based rates were higher than clinic rates for diarrhea and AFI, this difference being several-fold greater in the rural than urban site.

CONCLUSIONS

Individuals in poor Kenyan communities still suffer from a high burden of infectious diseases, which likely hampers their development. Urban slum and rural disease incidence and clinic utilization are sufficiently disparate in Africa to warrant data from both settings for estimating burden and focusing interventions.

An Assessment of Mixed-Modeling Approaches for Characterizing Profiles of Time-Varying Response and Predictor Variables

A general statistical modeling approach was tested for characterizing the relationship between pathogen inoculum density (or other biological response variables) and environmental variables when the data are collected as temporal profiles of observations within multiple locations or years. The approach, based on the use of linear mixed models, simultaneously accounts for serial correlations of the observations within each time profile, the random effects of location–year (or other grouping factors), and the cross-correlation of the environmental variables, and is appropriate when the environmental effects on the response variable or its transformation (Y) are distributed over several times (e.g., days). Stability and precision of parameter estimates for environmental effects over multiple time lags were achieved through the use of polynomial constraints within a likelihood-based full mixed-model fit; from the parameter estimates, marginal effects of environmental variables and weights for individual time lags were determined. The mixed model was directly expanded, through the incorporation of smoothing functions, to potentially account for possible longer-term trends in the temporal profiles unrelated to the environmental variables being considered. The new approach described here (with or without a smoothing function) generalizes a previously used—and computationally less demanding—two-stage (composite) approach. In the previous approach, constrained parameter estimates and associated weights were first determined without consideration of serial correlation, cross-correlation of environmental variables, and the random effects of location–year; then, a mixed-model fit was accomplished using the fixed time-lag weights derived in the first step. Using data for inoculum density of Gibberella zeae on wheat spikes from 27 location–years, similar results were achieved with the full mixed model and the two-stage approaches, in terms of both the calculated parameters and predictions of Y. With the use of smoothing functions, the precision of the predictions was improved but the general conclusions regarding environmental effects on Y were not affected. Thus, in the particular example data set, previously derived conclusions regarding environmental effects on inoculum density were robust in terms of the statistical methodology used in analysis; most researchers will find the two-stage approach much easier to implement for the analysis of multiple profiles of time-varying observations.