Epidemiology of Plasmodium falciparum Infections in a Semi-Arid Rural African Setting: Evidence of Reactive Case Detection in Northwestern Kenya

In northwestern Kenya, Turkana County has been historically considered unsuitable for stable malaria transmission because of its unfavorable climate and predominantly semi-nomadic population; consequently, it is overlooked during malaria control planning. However, the area is changing, with substantial development, an upsurge in travel associated with resource extraction, and more populated settlements forming. Recently, numerous malaria outbreaks have highlighted the need to characterize malaria transmission and its associated risk factors in the region to inform control strategies. Reactive case detection of confirmed malaria cases at six health facilities across central Turkana was conducted from 2018 to 2019. Infections in household members of index cases were detected by malaria rapid diagnostic tests (RDTs) and PCR tests, and they were grouped according household and individual characteristics. The relationships between putative risk factors and infection were quantified by multilevel logistic regression models. Of the 3,189 household members analyzed, 33.6% had positive RDT results and/or PCR test results. RDT-detected infections were more prevalent in children; however, PCR-detected infections were similarly prevalent across age groups. Recent travel was rarely reported and not significantly associated with infection. Bed net coverage was low and net crowding was associated with increased risks of household infections. Infections were present year-round, and fluctuations in prevalence were not associated with rainfall. These findings indicate year-round, endemic transmission with moderate population immunity. This is in stark contrast to recent estimates in this area. Therefore, further investigations to design effective intervention approaches to address malaria in this rapidly changing region and other similar settings across the Horn of Africa are warranted.

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Risk factors associated with malaria infection identified through reactive case detection in Zanzibar, 2012–2019

Malaria Journal ◽

10.1186/s12936-021-04025-1 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Humphrey R. Mkali ◽

Erik J. Reaves ◽

Shabbir M. Lalji ◽

Abdul-Wahid Al-mafazy ◽

Joseph J. Joseph ◽

...

Keyword(s):

Risk Factors ◽

Malaria Infection ◽

Universal Access ◽

Behavioural Change ◽

P Value ◽

Case Detection ◽

Reactive Case Detection ◽

Factors Associated ◽

Household Members ◽

Index Cases

Abstract Background Over the past two decades, Zanzibar substantially reduced malaria burden. As malaria decreases, sustainable improvements in control interventions may increasingly depend on accurate knowledge of malaria risk factors to further target interventions. This study aimed to investigate the risk factors associated with malaria infection in Zanzibar. Methods Surveillance data from Zanzibar’s Malaria Case Notification system from August 2012 and December 2019 were analyzed. This system collects data on malaria cases passively detected and reported by all health facilities (index cases), and household-based reactive case detection (RCD) activities linked to those primary cases. All members of households of the index cases were screened for malaria using a malaria rapid diagnostic test (RDT). Individuals with a positive RDT were treated with artemisinin-based combination therapy. Univariate and multivariate logistic regression analyses were done to investigate the association between RDT positivity among the household members and explanatory factors with adjustment for seasonality and clustering at Shehia level. Results A total of 30,647 cases were reported of whom household RCD was completed for 21,443 (63%) index case households and 85,318 household members tested for malaria. The findings show that younger age (p-value for trend [Ptrend] < 0.001), history of fever in the last 2 weeks (odds ratio [OR] = 35.7; 95% CI 32.3–39.5), travel outside Zanzibar in the last 30 days (OR = 2.5; 95% CI 2.3–2.8) and living in Unguja (OR = 1.2; 95% CI 1.0–1.5) were independently associated with increased odds of RDT positivity. In contrast, male gender (OR=0.8; 95% CI 0.7–0.9), sleeping under an LLIN the previous night (OR = 0.9; 95% CI 0.7–0.9), having higher household net access (Ptrend < 0.001), and living in a household that received IRS in the last 12 months (OR = 0.8; 95% CI 0.7–0.9) were independently associated with reduced odds of RDT positivity. A significant effect modification of combining IRS and LLIN was also noted (OR = 0.7; 95% CI 0.6–0.8). Conclusions The findings suggest that vector control remains an important malaria prevention intervention: they underscore the need to maintain universal access to LLINs, the persistent promotion of LLIN use, and application of IRS. Additionally, enhanced behavioural change and preventive strategies targeting children aged 5–14 years and travellers are needed.

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Incidence and Risk Factors of Illnesses Presumably Caused by A SARS-CoV-2 Infection in The General Population During The Lockdown Period: A Multi-Cohort Study.

10.21203/rs.3.rs-90873/v1 ◽

2020 ◽

Author(s):

Fabrice Carrat ◽

Mathilde Touvier ◽

Gianluca Severi ◽

Laurence Meyer ◽

Florence Jusot ◽

...

Keyword(s):

Risk Factors ◽

General Population ◽

Rural Areas ◽

Age Groups ◽

Sudden Onset ◽

Obese People ◽

Cox Models ◽

Chronic Respiratory Diseases ◽

High Prevalence ◽

Associated Risk Factors

Abstract Background Our main objectives were to estimate the incidence of illnesses presumably caused by SARS-CoV-2 infection during the lockdown period and to identify the associated risk factors.Methods Participants from 3 adult cohorts in the general population in France were invited to participate in a survey on COVID-19. The main outcome was possible COVID-19, defined as a sudden onset of cough, fever, dyspnea, ageusia and/or anosmia, that lasted more than 3 days and occurred during the 17 days before the survey. We used delayed-entry Cox models to identify associated factors.Results Between April 2, 2020 and May 12, 2020, 279,478 participants were invited, 116,903 validated the questionnaire and 106,848 were included in the analysis. Three thousand thirty-five cases of possible COVID-19 were reported during 62,099 person-months of follow-up. The cumulative incidences of possible COVID-19 were 6.2% (95% Confidence Interval (95%CI): 5.7%; 6.6%) on day 15 and 8.8% (95%CI 8.3%; 9.2%) on day 45 of lockdown. The risk of possible COVID-19 was lower in older age groups and higher in French regions with a high prevalence of SARS-CoV-2 infection, in participants living in cities >100,000 inhabitants (vs rural areas), when at least one child or adolescent was living in the same household, in overweight or obese people, and in people with chronic respiratory diseases, anxiety or depression or chronic diseases other than diabetes, cancer, hypertension or cardiovascular diseases. Conclusion The incidence of possible COVID-19 in the general population remained high during the first two weeks of lockdown, and decreased significantly thereafter. Modifiable and non-modifiable risk factors were identified.

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Prevalence of diarrhoea, and associated risk factors, in children aged 0-5 years, at two hospitals in Umuahia, Abia, Nigeria

UNED Research Journal ◽

10.22458/urj.v9i1.1672 ◽

2017 ◽

Vol 9 (1) ◽

pp. 7-14

Author(s):

Adanma Florence Nwaoha ◽

Camelita Chima Ohaeri ◽

Ebube Charles Amaechi

Keyword(s):

Risk Factors ◽

Health Workers ◽

Age Groups ◽

Medical Centers ◽

Faecal Samples ◽

Potential Risk Factors ◽

Stool Samples ◽

The Government ◽

Associated Risk Factors ◽

And Control

Diarrhoea is the second leading cause of infectious morbidity and mortality in children under five years of age. This study aimed at identifying the most common parasites and potential risk factors for diarrhoea among children 0-5 years attending Abia State Specialist hospital and Federal Medical Centre, Umuahia, in south eastern Nigeria. We used 400 faecal samples from children with diarrhoea –and 200 without– in combination with hospital-based case control and a questionnaire Stool samples were processed with direct normal saline and formal-ether sedimentation method for parasitological studies. More males than females were infected in nearly all age groups in both diarrhoeal and control groups (X2=23.04, df=1, P<0.05: X2=11.52, df=1, P<0.05 respectively). Amachara had more infections (X2=0.15, df=1, P< 0.05). January had the highest rate of infection (22.5%). Main clinical features were watery depositions over 3 times a day, diarrhoea lasting for days, fever, vomiting, and dehydration. Mothers learned about the problem through health workers, television and in medical centers. Risk correlated with mother’s education, occupation, latrine type, waste water disposal, hand washing, kitchen cleaning; sources and storage of water; and bottle milk (P< 0.05).Ignorance greatly contributed to the spread of parasitic disease in the area: the government should improve education and other strategies to alleviate the spread of the disease..

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Epidemiology and Risk Factors for Bacteremia in Pediatric and Adolescent Patients

Journal of Pharmacy Practice ◽

10.1177/0897190019868056 ◽

2019 ◽

pp. 089719001986805 ◽

Cited By ~ 1

Author(s):

Kayla R. Stover ◽

Austin Morrison ◽

Tia Collier ◽

Elisabeth Schneider ◽

Jamie L. Wagner ◽

...

Keyword(s):

Risk Factors ◽

Methicillin Resistance ◽

Control Strategies ◽

Positive Culture ◽

Secondary Outcome ◽

Tertiary Referral Center ◽

Adolescent Patients ◽

Causative Agents ◽

Patients At Risk ◽

Associated Risk Factors

Background: Epidemiology and risk factors for bacteremia in pediatric and adolescent patients have not been fully elucidated. Objective: The purpose of this study was to identify primary causative agents of bacteremia in pediatric and adolescent patients and associated risk factors. We hypothesized that these would be different than those seen in adults. Patients and Methods: This retrospective cohort, epidemiologic evaluation included patients admitted to a tertiary referral center from January 01, 2013, to December 31, 2015. Patients <18 years old with a confirmed positive blood culture were included; the first positive culture per organism per patient was analyzed. The primary outcome was to determine the most frequent causative organisms of bacteremia; the secondary outcome was an evaluation of risk factors for acquiring staphylococcal bacteremia. Results: A total of 913 isolates were evaluated, including 92 unique organisms. The most frequently identified were Staphylococcus epidermidis (238/913, 26.1%), followed by Staphylococcus aureus (136/913, 14.9%). Methicillin resistance was observed in 60.3% of S aureus. Two hundred thirty-six patients were included in the risk factor analysis. Prematurity, previous antibiotics, and intubation/ventilation were more likely associated with S epidermidis ( P < .001, P < .001, and P = .032, respectively). Patients with a recent or previous hospitalization and those with dermatitis/eczema were statistically more likely to grow S aureus ( P < .001, P = .029, respectively). Conclusions: Although epidemiology of organisms associated with pediatric and adolescent bacteremia was similar to adults, risk factors were different than seen in that population. Further understanding of these risk factors may be helpful in developing preemptive infection control strategies in patients at risk.

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Investigation of the temporal roaming behaviour of free-roaming domestic dogs in Indigenous communities in northern Australia to inform rabies incursion preparedness

Scientific Reports ◽

10.1038/s41598-019-51447-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Elizabeth K. Maher ◽

Michael P. Ward ◽

Victoria J. Brookes

Keyword(s):

Risk Factors ◽

Control Strategies ◽

Indigenous Communities ◽

Domestic Dog ◽

Northern Australia ◽

Remote Communities ◽

Canine Rabies ◽

Torres Strait ◽

Associated Risk Factors ◽

The Impact

Abstract Australia is canine rabies free but free-roaming, domestic dog populations in remote northern communities are at risk of an incursion due to proximity to rabies-endemic south-east Asia. Unrestricted contact between dogs could facilitate rabies spread following an incursion, and increase the impact on both dogs and people. Whilst dog vaccination is the foundation of rabies prevention, control strategies could be enhanced by understanding the temporal pattern of roaming and associated risk factors, so that movement restrictions can be targeted. Global positioning system datasets from 132 dogs in eight Indigenous communities in the Torres Strait and Northern Peninsula Area (NPA) of Australia were analysed using regression methods. The influence of risk factors (including age, sex, location, season and hour of day) on dogs’ distance from their residences were assessed. Dogs roamed furthest in the NPA and during the dry season. Daily peaks in mean roaming distance were observed at 1000–1100 hrs and 1700–1800 hrs in the Torres Strait, and 1700–1800 hrs in the NPA. These findings demonstrate that understanding community-specific temporal roaming patterns can inform targeted movement restrictions during an outbreak of rabies in remote communities in northern Australia.

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The Association of Hepatitis C Serological Status with Several Risk Factors in Indonesia

International Scholarly Research Notices ◽

10.1155/2016/3018135 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4

Author(s):

Noer Endah Pracoyo ◽

Made Ayu Lely Suratri ◽

Roselinda Roselinda ◽

Vivi Setiawaty

Keyword(s):

Risk Factors ◽

Hepatitis C ◽

Total Sample ◽

Biomedical Data ◽

Cross Sectional ◽

Demographic Group ◽

Serological Status ◽

Household Members ◽

One Year ◽

Associated Risk Factors

Hepatitis is an inflammation of the liver commonly caused by viral infection such as hepatitis A, B, C, D, and E but it is also possible by other causes. Infection with hepatitis C virus is also referred to as a disguise because the early infection is often asymptomatic that often goes undetected. This study aims at determining the several associated risk factors with hepatitis C serological status. The study design is cross-sectional. The biomedical data collection was carried out in 33 provinces in Indonesia with a population in urban blocks, census in Indonesia, where the sample is all household members over the age of one year from selected households by signing the informed consent. Total block census in selected urban area is about 971-block census with a total sample of 15.536 households. The results showed that there is a correlation between hepatitis C serological status and demographic group and that the age and occupation groups showed significant P value obtained at 0.001 (OR = 3.27, CI = 1.84–5.81) and 0.209 (OR = 0.23, CI = 0.59–0.94). In conclusion, there are risk factors such as age and occupation that have a correlation of being infected with hepatitis C serological status.

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Rumen fluke (Calicophoron daubneyi) on Welsh farms: prevalence, risk factors and observations on co-infection withFasciola hepatica

Parasitology ◽

10.1017/s0031182016001797 ◽

2016 ◽

Vol 144 (2) ◽

pp. 237-247 ◽

Cited By ~ 17

Author(s):

RHYS ALED JONES ◽

PETER M. BROPHY ◽

E. SIAN MITCHELL ◽

HEFIN WYN WILLIAMS

Keyword(s):

Risk Factors ◽

Fasciola Hepatica ◽

Significant Negative Correlation ◽

Herd Size ◽

Logistic Regression Models ◽

Sunshine Hours ◽

Calicophoron Daubneyi ◽

Cattle Herds ◽

Associated Risk Factors ◽

The Uk

SUMMARYReports ofCalicophoron daubneyiinfecting livestock in Europe have increased substantially over the past decade; however, there has not been an estimate of its farm level prevalence and associated risk factors in the UK. Here, the prevalence ofC. daubneyiacross 100 participating Welsh farms was recorded, with climate, environmental and management factors attained for each farm and used to create logistic regression models explaining its prevalence. Sixty-one per cent of farms studied were positive forC. daubneyi, with herd-level prevalence for cattle (59%) significantly higher compared with flock-level prevalence for sheep (42%,P= 0·029). Co-infection betweenC. daubneyiandFasciola hepaticawas observed on 46% of farms; however, a significant negative correlation was recorded in the intensity of infection between each parasite within cattle herds (rho = −0·358,P= 0·007). Final models showed sunshine hours, herd size, treatment regularity againstF. hepatica, the presence of streams and bog habitats, and Ollerenshaw index values as significant positive predictors forC. daubneyi(P< 0·05). The results raise intriguing questions regardingC. daubneyiepidemiology, potential competition withF. hepaticaand the role of climate change inC. daubneyiestablishment and its future within the UK.

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Infestation and Identification of Ixodid Tick in Cattle: The Case of Arbegona District, Southern Ethiopia

Journal of Veterinary Medicine ◽

10.1155/2016/9618291 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Jelalu Kemal ◽

Nateneal Tamerat ◽

Temesgen Tuluka

Keyword(s):

Risk Factors ◽

Tick Infestation ◽

Age Groups ◽

Ixodid Tick ◽

Southern Ethiopia ◽

Main Body ◽

Body Parts ◽

High Burden ◽

Associated Risk Factors ◽

Relative Prevalence

The study was conducted from October 2014 to June 2015 to estimate tick prevalence and identify major tick genera infesting cattle and the associated risk factors in Arbegona district, southern Ethiopia. A total of 2024 adult ticks were collected from main body parts of animals and eight species of ticks which belong to three genera were identified. Questionnaire survey was employed concerning the general case on the tick infestation problems on the cattle. From 384 cattle examined, 291 (75.7%) were found to be infested with one or more types of tick species. The relative prevalence of each genera was Amblyomma (34.9%), Rhipicephalus (Boophilus) (26.6%), Hyalomma (19.2%), and Rhipicephalus (19%). The prevalence of tick infestation in good (65.5%), medium (74%), and poor body condition animal (100%) was found to be statistically significant (p<0.05). There was also significantly (p<0.05) higher prevalence in old (98.4%) than adult (78.8%) and young (59.8%) age groups of animals. In the survey, 87.5% of respondents believe that there was tick infestation problem in their locality. This study showed there was high burden and prevalence of ticks that still play major roles in reducing productivity and cause health problems of cattle in the area which call for urgent attention.

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Intestinal Schistosomiasis among Primary Schoolchildren in Two On-Shore Communities in Rorya District, Northwestern Tanzania: Prevalence, Intensity of Infection and Associated Risk Factors

Journal of Parasitology Research ◽

10.1155/2016/1859737 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 10

Author(s):

David Z. Munisi ◽

Joram Buza ◽

Emmanuel A. Mpolya ◽

Safari M. Kinung’hi

Keyword(s):

Risk Factors ◽

Control Strategies ◽

Geometric Mean ◽

Infection Intensity ◽

Risk Groups ◽

Public Health Importance ◽

Cross Sectional ◽

Level Of Education ◽

Treatment History ◽

Associated Risk Factors

In Tanzania,Schistosoma mansoniis of great public health importance. Understanding the prevalence and infection intensity is important for targeted, evidence-based control strategies. This study aimed at studying the prevalence, intensity, and risk factors ofS. mansoniamong schoolchildren in the study area. A cross-sectional study was conducted in Busanga and Kibuyi villages. Sampled 513 schoolchildren provided stool specimens which were examined using kato-katz method. Pretested questionnaire was used to collect sociodemographic data and associated risk factors. The prevalence ofS. mansoniinfection was 84.01%, with geometric mean egg intensity of 167.13 (95% CI: 147.19–189.79) eggs per gram of stool (epg). Other parasites detected wereAscaris lumbricoides(1.4%) and hookworms (1.4%). The geometric mean infection intensity in Busanga and Kibuyi were 203.70 (95% CI: 169.67–244.56) and 135.98 (95% CI: 114.33–161.73) epg, respectively. Light, moderate, and heavy infection intensities were 34.11%, 39.91%, and 25.99%, respectively. Village of residence, parent’s level of education, toilet use, and treatment history were predictors of infection. The high prevalence and infection intensity in this study were associated with village, parent’s level of education, inconsistent toilet use, and treatment history. To control the disease among at-risk groups, these factors need to be considered in designing integrated schistosomiasis control interventions.

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Timing for Closed Reduction Procedure for Developmental Dysplasia of the Hip and its Failure Analysis

10.21203/rs.3.rs-37192/v3 ◽

2020 ◽

Author(s):

Zhiqiang Zhang ◽

Hao Li ◽

Hai Li ◽

Ziming Zhang

Keyword(s):

Risk Factors ◽

Closed Reduction ◽

Age Groups ◽

Significant Risk ◽

Developmental Dysplasia ◽

Operating Characteristics ◽

Logistic Regression Models ◽

Midterm Outcome ◽

Group I ◽

Dysplasia Of The Hip

Abstract Background It remains controversial whether the older age to perform closed reduction (CR) procedure for developmental dysplasia of the hip (DDH), the higher incidence of complications. The aim of this study is to evaluate the midterm outcome of CR for DDH among difference age groups, and to analyze and identify risk factors for the failure of this procedure. Methods Clinical data of 107 DDH patients, who received CR, were retrospectively reviewed. Data were divided into three groups according to initial treatment age (Group I: younger than 12 months; Group II: 12 months to less or equal to18 months; Group III: older than 18 months). The presence of avascular necrosis (AVN), residual acetabular dysplasia (RAD), re-dislocation, and further surgeries (FS) were observed. The risk factors were identified for those outcomes aforementioned using univariable logistic regression models. For identified risk factor age, pre-op acetabular index (AI) and post-op AI, their prediction of CR failure were evaluated by receiver operating characteristics curve (ROC).Results A total of 107 patients (156 hips) undergoing CR procedure were evaluated with a median age at initial reduction of 13.0±5.4 months (range, 4 to 28 mo). Mean follow-up time in this study was 6.7±0.8 years (range, 3-8 years). The incidence of AVN, RAD and re-dislocation was 15.4% (24/156), 17.3% (27/156) and 14.7% (23/156) respectively. For AVN, RAD and re-dislocation, the significant risk factors are pre-op IHDI IV (p=0.033), age≥18 months (p=0.012), and pre-op IHDI IV (p=0.004) and walking (p=0.011), respectively. The areas under the ROC curve of each type of failures were 0.841 (post-op AI), 0.688 (pre-op AI) and 0.650 (age).Conclusions Severe DDH patients older than 18 months with CR procedure may result in a high risk of RAD complication. Re-dislocation is significantly associated with pre-op IHDI IV and walking. Patients, who are older than 12.5 months or have a pre-op AI of 38.7° or a post-op AI of 26.4°, are also more likely to fail of CR procedure.

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