How "Subclinical" is Subclinical Tuberculosis? An Analysis of National Prevalence Survey Data from Zambia.

BACKGROUND: Pulmonary tuberculosis infection can manifest in different states, including subclinical tuberculosis. It is commonly defined as confirmed tuberculosis without the classic symptoms (commonly, persistent cough for ≥2 weeks). This narrow definition likely poses limitations for surveillance and control measures. The aims of the current study were to characterize the clinical presentation of tuberculosis; estimate the prevalence of subclinical tuberculosis among individuals with bacteriologically confirmed tuberculosis, using various definitions; and investigate risk factors for subclinical as opposed to clinical tuberculosis in a population-based survey. METHODS: We conducted a secondary analysis of data from a nationally representative tuberculosis prevalence survey from Zambia in 2013-2014, in which participants were screened for tuberculosis based on chest radiographic findings and symptoms. Tuberculosis was defined as culture-positive or GeneXpert MTB/RIF test-positive sputum. Risk factors for subclinical tuberculosis were assessed by means of multivariable logistic regression. RESULTS: Of 257 participants with confirmed tuberculosis, 104 (40.5%) were without cough persisting ≥2 weeks. Only 23 (22.1%) of these did not present with any other common symptoms. Those without cough persisting ≥2 weeks frequently reported other symptoms, particularly chest pain (46.2%) and weight loss (38.5%); 36 (34.6%) reported experiencing other symptoms persisting ≥4 weeks. Female subjects were more likely to report no cough persisting ≥2 weeks, as were relatively wealthier individuals. CONCLUSIONS: The commonly used definition of subclinical tuberculosis includes a large proportion of individuals who have other tuberculosis-suggestive symptoms. Requiring cough ≥2 weeks for tuberculosis diagnosis likely misses many active tuberculosis infections and allows a large reservoir of likely transmissible tuberculosis to remain undetected.

Molecular methods for tracking residual Plasmodium falciparum transmission in a close-to-elimination setting in Zanzibar.

BACKGROUND: Molecular detection of low-density Plasmodium falciparum infections is essential for surveillance studies conducted to inform malaria control strategies in close-to-elimination settings. Molecular monitoring of residual malaria infections usually requires a large study size, therefore sampling and diagnostic processes need to be economical and optimized for high-throughput. A method comparison was undertaken to identify the most efficient diagnostic procedure for processing large collections of community samples with optimal test sensitivity, simplicity, and minimal costs. METHODS: In a reactive case detection study conducted on Zanzibar, parasitaemia of 4590 individuals of all ages was investigated by a highly sensitive quantitative (q) PCR that targets multiple var gene copies per parasite genome. To reduce cost, a first round of positivity screening was performed on pools of dried blood spots from five individuals. Ten cycles of a pre-PCR were performed directly on the filter paper punches, followed by qPCR. In a second round, samples of positive pools were individually analysed by pre-PCR and qPCR. RESULTS: Prevalence in household members and neighbors of index cases was 1.7% (78/4590) with a geometric mean parasite density of 58 parasites/µl blood. Using qPCR as gold standard, diagnostic sensitivity of rapid diagnostic tests (RDTs) was 37% (29/78). Infections positive by qPCR but negative by RDT had mean densities of 15 parasites/µl blood. CONCLUSION: The approach of pre-screening reactive case detection samples in pools of five was ideal for a low prevalence setting such as in Zanzibar. Performing direct PCR on filter paper punches saves substantial time and justifies the higher cost for a polymerase suitable for amplifying DNA directly from whole blood. Molecular monitoring in community samples provided a more accurate picture of infection prevalence, as it identified a potential reservoir of infection that was largely missed by RDT. The developed qPCR-based methodology for screening large sample sets represents primarily a research tool that should inform the design of malaria elimination strategies. It may also prove beneficial for diagnostic tasks in surveillance-response activities.

Sustaining LLIN coverage with continuous distribution: the school net programme in Tanzania.

Most malaria-endemic countries have struggled in the past decade to establish effective national-scale continuous distribution mechanisms for long-lasting insecticidal nets (LLINs). Since the implementation of the Tanzania National Voucher Scheme in 2004 and mass-distribution campaigns in 2009-2011 and 2015-2016, Tanzania has been committed to finding new and innovative ways of achieving and maintaining universal bed net coverage. Planning for the School Net Programme (SNP) began in 2011 and in 2013, the country piloted a SNP in three regions. Nets were distributed annually to children attending schools in selected primary and secondary grades. Intra-family re-distribution was assumed, and hence the family as a whole, rather than just the children themselves, were the targeted beneficiaries. The programme has since expanded to 14 regions and has seen six rounds of annual distribution. In its fifth year, 3 million nets were distributed at a cost of USD 3.64 per net and USD 0.60 per person-year of protection (including the net). ITN access and use were maintained at a high level (~ 50-75%) over the first 4 years of distribution within selected evaluation areas, even in the absence of a mass distribution event. Net distribution through primary schools has proven to be a feasible and effective strategy for maintaining consistently high coverage in Tanzania.

Screening Positive for Cognitive Impairment: Impact on Healthcare Utilization and Provider Action in Primary and Specialty Care Practices.

BACKGROUND: Alzheimer's disease, the most common cause of dementia, goes unrecognized in half of patients presenting to healthcare providers and is associated with increased acute care utilization. Routine cognitive screening of older adults in healthcare settings could improve rates of dementia diagnosis and patterns of healthcare utilization. OBJECTIVE: To evaluate the impact of screening positive for cognitive impairment on provider action in primary and specialty care practices and patient healthcare utilization. DESIGN: Individuals asymptomatic for cognitive impairment completed cognitive screening with the Mini-Cog (MC). Outcomes included MC screen-positive rates, provider follow-up actions, and healthcare utilization for all participants over a period of 36 months (18 months prior to and following MC screening). Data were extracted from the electronic medical record (EMR). Healthcare provider interventions and healthcare utilization for screen-positive and -negative groups, before and after screening, were compared. PARTICIPANTS: Primary and specialty care patients (n = 787) aged ≥ 65 without history of cognitive impairment seen in HealthPartners, an integrated healthcare system in Minnesota and Western Wisconsin. KEY RESULTS: In primary care and neurology practices combined, over the entire 36-month study window, individuals screening positive showed 32% higher rates of ED visits (p < 0.05) pre and post-screening compared to those screening negative. Screen positive also showed 39% higher rates of hospitalizations pre-screening (p < 0.05) and 58% higher rates post-screening (p < 0.01). While screen-detected cognitive impairment was associated with some relevant provider follow-up action in 32% of individuals, subsequent healthcare utilization did not change between the 18-month pre- and post-screening periods. CONCLUSION: Despite being associated with higher rates of healthcare utilization, screening positive on the MC led to a change in provider action in a minority of cases and did not reduce post-screening healthcare utilization. Screening for cognitive impairment alone is not sufficient to alter patterns of provider practice or patient healthcare utilization.

Estimation of malaria parasite reservoir coverage using reactive case detection and active community fever screening from census data with rapid diagnostic tests in southern Zambia: a re-sampling approach.

BACKGROUND AND METHODS: In areas where malaria transmission has been suppressed by vector control interventions many malaria control and elimination programmes are actively seeking new interventions to further reduce malaria prevalence, incidence and transmission. Malaria infection prevalence and incidence has been shown to cluster geographically, especially at lower transmission levels, and as such a reactive strategy is frequently used, by which index cases presenting to a passive surveillance system are used to target small areas for testing and treatment, reactive case detection (RCD), or focal drug administration (fDA). This study utilizes geo-located data from a census with parasitological testing with rapid diagnostic tests (RDTs) and treatment-seeking data collection conducted in southern Zambia to estimate the coverage of RCD or fDA in terms of the population and parasite reservoir as well as the operational requirements of such strategies, using a re-sampling algorithm developed exclusively for this purpose. This re-sampling algorithm allows for the specification of several parameters, such that different operational variants of these reactive strategies can be examined, including varying the search radius, screening for fever, or presumptive treatment (fDA). RESULTS: Results indicate that RCD, fDA and active fever screening followed by RCD, even with search radii over several hundered meters will only yield limited coverage of the RDT positive parasite reservoir during a short period. Long-term use of these strategies may increase this proportion. Reactive strategies detect a higher proportion of the reservoir of infections than random searches, but this effect appears to be greater in areas of low, but not moderate malaria prevalence in southern Zambia. DISCUSSION: Increases in the sensitivity of RDTs could also affect these results. The number of individuals and households that need to be searched increase rapidly, but approximately linearly with search radius. CONCLUSIONS: Reactive strategies in southern Zambia yield improved identification of the parasite reservoir when targeted to areas with prevalence less than 10%. The operational requirements of delivering reactive strategies routinely are likely to prevent their uptake until prevalence falls far below this level.

Achieving a Safe Endotracheal Tube Cuff Pressure in the Prehospital Setting: Is It Time to Revise the Standard Cuff Inflation Practice?

Numerous studies have reported unsafe endotracheal tube (ETT) cuff pressures (CP) in the prehospital environment. The purpose of this study was to identify an optimal cuff inflation volume (CIV) to achieve a safe CP (20-30 cmH2O). This observational study utilized 30 recently harvested ovine tracheae, which were warmed from refrigeration in a water bath at 85°F prior to testing. Each trachea was intubated with five different ETT sizes (6.0-8.0 mm), and each size tube was tested with six cuff inflation volumes (5-10 cc). The order of ETT size for each trachea and CIV for each size ETT was randomly pre-assigned. Data were descriptively summarized and categorized before mixed-effects logistic regression was used to determine optimal CIV. Only 113 CP measurements (12.6%, N = 900) were within the optimal range (M = 54.75 cmH2O, SD = 38.52), all of which resulted from a CIV 6 or 7 cc (61% and 39%, respectively). CIVs of 5 cc (n = 150) resulted in underinflation (<20 cmH2O) in all instances, while CIVs of 8, 9, or 10 cc (n = 150 each) resulted in overinflation (>30 cmH2O) in all instances, regardless of ETT size. The odds of achieving a safe CP were greater with CIV of 6 cc for tube sizes 6.0 (OR = 15.9, 95% CI = 3.85-65.58, p < 0.01) and 6.5 mm (OR = 3.16, 95% CI = 1.06-9.39, p = 0.039); however, there was no significant difference in the odds of achieving a safe CP between CIV of 6 and 7 cc for tube sizes 7.0, 7.5, or 8.0 mm. Neither trachea circumference (M = 7.11 cm, SD = 0.40), nor tissue temperature (M = 81.32°F, SD = 0.93) were found to be significant predictors of CP (p = 0.20 and 0.81, respectively). Our study showed a high frequency of CP measurements outside of the desired norms. The CIV range of 6-7 cc resulted in the highest likelihood of achieving the desired cuff pressure range, while cuffs inflated with 8-10 cc resulted in dangerously high CPs in all instances. In the absence of a more ideal solution, the results of this study suggest that narrowing the recommended CIV from 5-10 cc to 6-7 cc might be a reasonable target for any tube size.

Does computed tomographic scan affect diagnosis and management of patients with suspected renal colic?

BACKGROUND: Patients with renal colic commonly present to the emergency department (ED) and are usually treated with analgesics, antiemetics and hydration. Computed tomographic (CT) scan is commonly utilized in evaluating patients with suspected renal colic. OBJECTIVES: We compared diagnosis and treatment plans before and after CT in patients with suspected renal colic with the aim to evaluate how often changes in diagnosis, treatment and disposition are made. METHODS: In this prospective observational study, we enrolled a convenience sample of clinically Stable ED patients older than 17 with suspected renal colic for whom CT was planned. Exclusion criteria were: chronic kidney disease, urinary tract infection, recent CT and history of previous kidney stone. Pre-CT and Post-CT surveys were completed by the treating provider. RESULTS: The discharge diagnosis was renal colic in 62 of 93 enrolled patients (67%). Urinalysis showed blood in 52 of these patients (84%). CT confirmed obstructing kidney or bladder stone in 50 patients. There were five cases of alternative diagnoses noted on CT scan. After CT scan, 7 patients had changes in disposition. Sixteen providers felt that CT would not change management. In these cases, CT offered no alternative diagnosis and didn't change disposition. CONCLUSION: CT scan didn't change management when providers did not expect it would. This indicates that providers who are confident with the diagnosis of renal colic should consider forgoing a CT scan. CT scan did occasionally find important alternative diagnoses and should be utilized when providers are considering other concerning pathology.

Prevalence of subclinical pulmonary tuberculosis in adults in community settings: an individual participant data meta-analysis.

BACKGROUND: Subclinical pulmonary tuberculosis, which presents without recognisable symptoms, is frequently detected in community screening. However, the disease category is poorly clinically defined. We explored the prevalence of subclinical pulmonary tuberculosis according to different case definitions. METHODS: We did a one-stage individual participant data meta-analysis of nationally representative surveys that were conducted in countries with high incidence of tuberculosis between 2007 and 2020, that reported the prevalence of pulmonary tuberculosis based on chest x-ray and symptom screening in participants aged 15 years and older. Screening and diagnostic criteria were standardised across the surveys, and tuberculosis was defined by positive Mycobacterium tuberculosis sputum culture. We estimated proportions of subclinical tuberculosis for three case definitions: no persistent cough (ie, duration ≥2 weeks), no cough at all, and no symptoms (ie, absence of cough, fever, chest pain, night sweats, and weight loss), both unadjusted and adjusted for false-negative chest x-rays and uninterpretable culture results. FINDINGS: We identified 34 surveys, of which 31 were eligible. Individual participant data were obtained and included for 12 surveys (620 682 participants) across eight countries in Africa and four in Asia. Data on 602 863 participants were analysed, of whom 1944 had tuberculosis. The unadjusted proportion of subclinical tuberculosis was 59·1% (n=1149/1944; 95% CI 55·8-62·3) for no persistent cough and 39·8% (773/1944; 36·6-43·0) for no cough of any duration. The adjusted proportions were 82·8% (95% CI 78·6-86·6) for no persistent cough and 62·5% (56·6-68·7) for no cough at all. In a subset of four surveys, the proportion of participants with tuberculosis but without any symptoms was 20·3% (n=111/547; 95% CI 15·5-25·1) before adjustment and 27·7% (95% CI 21·0-36·4) after adjustment. Tuberculosis without cough, irrespective of its duration, was more frequent among women (no persistent cough: adjusted odds ratio 0·79, 95% CI 0·63-0·97; no cough: adjusted odds ratio 0·76, 95% CI 0·62-0·93). Among participants with tuberculosis, 29·1% (95% CI 25·2-33·3) of those without persistent cough and 23·1% (18·8-27·4) of those without any cough had positive smear examinations. INTERPRETATION: The majority of people in the community who have pulmonary tuberculosis do not report cough, a quarter report no tuberculosis-suggestive symptoms at all, and a quarter of those not reporting any cough have positive sputum smears, suggesting infectiousness. In high-incidence settings, subclinical tuberculosis could contribute considerably to the tuberculosis burden and to Mycobacterium tuberculosis transmission. FUNDING: Mr Willem Bakhuys Roozeboom Foundation.

Drivers of informal sector and non-prescription medication use in pediatric populations in a low- and middle-income setting: A prospective cohort study in Zambia.

Obtaining medication from the informal sector is common in low- and middle- income countries. Informal sector use increases the risk for inappropriate medication use, including inappropriate antibiotic usage. Infants are at the highest risk of complications from inappropriate medication use, yet there is insufficient knowledge about the risk factors driving caregivers to obtain medication from the informal sector for young children. We aimed to define infant and illness characteristics associated with use of medication purchased in the informal sector for infants up to fifteen months of age in Zambia. We used data from, a prospective cohort study (ROTA-biotic) conducted among 6 weeks to 15 months old children in Zambia, which is nested within an ongoing phase III rotavirus vaccine trial (Clinicaltrial.gov NCT04010448). Weekly in-person surveys collected information about illness episodes and medication usage for the trial population and for a community control cohort. The primary outcome for this study was whether medication was purchased in the formal sector (hospital or clinic) or informal sector (pharmacy, street vendor, friend/relative/neighbor, or chemical shop) per illness episode. Descriptive analyses were used to describe the study population, and the independent and medication use variables stratified by the outcome. A mixed-effects logistic regression model with a participant-level random intercept was used to identify independent variables associated with the outcome. The analysis included 439 participants accounting for 1927 illness episodes over fourteen months in time. Medication was purchased in the informal sector for 386 (20.0%) illness episodes, and in the formal sector for 1541 (80.0%) illness episodes. Antibiotic usage was less common in the informal sector than in the formal sector (29.3% vs 56.2%, p < 0.001, chi-square). Most medications purchased in the informal sector were orally administered (93.4%), and non-prescribed (78.8%). Increased distance from the closest study site (OR: 1.09; 95% CI: 1.01, 1.17), being included in the community cohort site (OR: 3.18; 95% CI: 1.86, 5.46), illnesses with general malaise fever, or headache (OR: 2.62; 95% CI: 1.75, 3.93), and wound/skin disease (OR: 0.36; 95% CI: 0.18, 0.73) were associated with use of medication from the informal sector. Sex, socioeconomic status, and gastrointestinal disease were not associated with use of medication from the informal sector. Informal sector medication use is common and, in this study, risk factors for obtaining medications in the informal sector included a long distance to a formal clinic, type of illness, and not being enrolled in a clinical trial. Continued research on medication use from the informal sector is crucial and should include generalizable study populations, information on severity of disease, emphasis on qualitative research, and a move towards testing interventions that aim to improve access to formal health care settings. Our findings suggest that improved access to formal health care services may decrease reliance on medication from the informal sector for infants.

Modelling the impact of interventions on imported, introduced and indigenous malaria infections in Zanzibar, Tanzania.

Malaria cases can be classified as imported, introduced or indigenous cases. The World Health Organization's definition of malaria elimination requires an area to demonstrate that no new indigenous cases have occurred in the last three years. Here, we present a stochastic metapopulation model of malaria transmission that distinguishes between imported, introduced and indigenous cases, and can be used to test the impact of new interventions in a setting with low transmission and ongoing case importation. We use human movement and malaria prevalence data from Zanzibar, Tanzania, to parameterise the model. We test increasing the coverage of interventions such as reactive case detection; implementing new interventions including reactive drug administration and treatment of infected travellers; and consider the potential impact of a reduction in transmission on Zanzibar and mainland Tanzania. We find that the majority of new cases on both major islands of Zanzibar are indigenous cases, despite high case importation rates. Combinations of interventions that increase the number of infections treated through reactive case detection or reactive drug administration can lead to substantial decreases in malaria incidence, but for elimination within the next 40 years, transmission reduction in both Zanzibar and mainland Tanzania is necessary.

Risk of imported malaria infections in Zanzibar: a cross-sectional study.

BACKGROUND: Zanzibar has made substantial progress in malaria control with vector control, improved diagnosis, and artemisinin-based combination therapy. Parasite prevalence in the population has remained around 1% but imported infections from mainland Tanzania contribute to sustained local transmission. Understanding travel patterns between mainland Tanzania and Zanzibar, and the risk of malaria infection, may help to control malaria importation to Zanzibar. METHODS: A rolling cross-sectional survey linked to routine reactive case detection of malaria was carried out in Zanzibar between May 2017 and October 2018. Households of patients diagnosed with malaria at health facilities were surveyed and household members were tested for malaria using rapid diagnostic tests and a sub-sample by quantitative PCR (qPCR). Interviews elicited a detailed travel history of all household members who had travelled within the past two months, including trips within and outside of Zanzibar. We estimated the association of malaria infection with travel destinations in pre-defined malaria endemicity categories, trip duration, and other co-variates using logistic regression. RESULTS: Of 17,891 survey participants, 1177 (7%) reported a recent trip, of which 769 (65%) visited mainland Tanzania. Among travellers to mainland Tanzania with travel destination details and a qPCR result available, 241/378 (64%) reported traveling to districts with a 'high' malaria endemicity and for 12% the highest endemicity category was 'moderate'. Travelers to the mainland were more likely to be infected with malaria parasites (29%, 108/378) than those traveling within Zanzibar (8%, 16/206) or to other countries (6%, 2/17). Among travellers to mainland Tanzania, those visiting highly endemic districts had a higher odds of being qPCR-positive than those who travelled only to districts where malaria-endemicity was classified as low or very low (adjusted odd ratio = 7.0, 95% confidence interval: 1.9-25.5). Among travellers to the mainland, 110/378 (29%) never or only sometimes used a mosquito net during their travel. CONCLUSIONS: Strategies to reduce malaria importation to Zanzibar may benefit from identifying population groups traveling to highly endemic areas in mainland Tanzania. Targeted interventions to prevent and clear infections in these groups may be more feasible than attempting to screen and treat all travellers upon arrival in Zanzibar.

The impact of reactive case detection on malaria transmission in Zanzibar in the presence of human mobility.

Malaria persists at low levels on Zanzibar despite the use of vector control and case management. We use a metapopulation model to investigate the role of human mobility in malaria persistence on Zanzibar, and the impact of reactive case detection. The model was parameterized using survey data on malaria prevalence, reactive case detection, and travel history. We find that in the absence of imported cases from mainland Tanzania, malaria would likely cease to persist on Zanzibar. We also investigate potential intervention scenarios that may lead to elimination, especially through changes to reactive case detection. While we find that some additional cases are removed by reactive case detection, a large proportion of cases are missed due to many infections having a low parasite density that go undetected by rapid diagnostic tests, a low rate of those infected with malaria seeking treatment, and a low rate of follow up at the household level of malaria cases detected at health facilities. While improvements in reactive case detection would lead to a reduction in malaria prevalence, none of the intervention scenarios tested here were sufficient to reach elimination. Imported cases need to be treated to have a substantial impact on prevalence.

Evaluation of long-lasting insecticidal net distribution through schools in Southern Tanzania.

Universal coverage with effective vector control remains the mainstay of malaria vector control in sub-Saharan Africa. Tanzania has utilized a number of mechanisms for the maintenance of long-lasting insecticidal net (LLIN) coverage over time. Schools have been identified as one potential channel for continuous distribution of LLIN. This research aims to evaluate an annual school-based LLIN distribution programme in Tanzania that began in 2013, called the School Net Programme (SNP). Following each of the first four rounds of SNP distribution, a household survey was conducted in intervention and comparison districts in Southern and Lake zones of Tanzania (N = 5083 households). Measures of ownership, access and use were compared between intervention and comparison districts. Determinants of reach were assessed in intervention districts. Population access to an LLIN increased from 63.1% (95% CI: 58.8, 67.5) to 76.5% (95% CI: 72.9, 80.0) in the intervention districts between the first and last surveys. Access also rose in the comparison districts from 51.4% (95% CI: 46.9, 55.9) to 79.8% (95% CI: 77.3, 82.0) following mass distribution and implementation of school-based distribution during the study period. LLIN use increased in intervention districts from 44.9% (95% CI: 40.5, 49.3) to 65.6% (95% CI: 59.4, 71.8) and from 57.2% (95% CI: 49.7, 64.7) to 77.4% (95% CI: 69.3, 85.5) specifically amongst primary school-aged children. Households reached by the SNP were wealthier households with children enrolled in school. The SNP in Tanzania was able to maintain population level LLIN ownership, use and access in the absence of mass distribution. The SNP successfully reached households that housed school-aged children. Alternative delivery strategies may need to be considered to reach households without children enrolled in schools that experienced fewer benefits from the programme.

Evaluation of facial cleanliness and environmental improvement activities: Lessons learned from Malawi, Tanzania, and Uganda.

The World Health Organization promotes the SAFE (Surgery, Antibiotics, Facial cleanliness, and Environmental improvements) strategy for trachoma control and prevention. The F&E components of the strategy focus on promotion of healthy hygiene and sanitation behaviors. In order to monitor F&E activities implemented across villages and schools in Malawi, Tanzania, and Uganda, an F&E Monitoring and Evaluation (FEME) framework was developed to track quarterly program outputs and to provide the basis for a pre and post evaluation of the activities. Results showed an increase in knowledge at the school and household levels, and in some cases, an increase in presence of hand/face washing stations. However, this did not always result in a change in trachoma prevention behaviors such as facial cleanliness or keeping compounds free of human feces. The results highlight that the F&E programs were effective in increasing awareness of trachoma prevention but not able to translate that knowledge into changes in behavior during the time between pre and post-surveys. This study also indicates the potential to improve the data collection and survey design and notes that the period of intervention was not long enough to measure significant changes.

Operational Coverage and Timeliness of Reactive Case Detection for Malaria Elimination in Zanzibar, Tanzania.

Since 2012, the Zanzibar Malaria Elimination Program has been implementing reactive case detection (RACD). Health facility (HF) staff send individual malaria case notifications by using mobile phones, triggering a review of HF records and malaria testing and treatment at the household level by a district malaria surveillance officer. We assessed the completeness and timeliness of this system, from case notification to household-level response. We reviewed two years (2015-2016) of primary register information in 40 randomly selected HFs on Zanzibar's two islands Unguja and Pemba and database records of case notifications from all registered HFs for the period 2013-16. The operational coverage of the system was calculated as proportion of HF-registered cases that were successfully reviewed and followed up at their household. Timeliness was defined as completion of each step within 1 day. Public HFs notified almost all registered cases (91% in Unguja and 87% in Pemba), and 74% of cases registered at public HFs were successfully followed up at their household in Unguja and 79% in Pemba. Timely operational coverage (defined as each step, diagnosis to notification, notification to review, and review to household-level response, completed within 1 day) was achieved for only 25% of registered cases in Unguja and 30% in Pemba. Records and data from private HFs on Unguja indicated poor notification performance in the private sector. Although the RACD system in Zanzibar achieved high operational coverage, timeliness was suboptimal. Patients diagnosed with malaria at private HFs and hospitals appeared to be largely missed by the RACD system.

Malaria infection prevalence and sensitivity of reactive case detection in Zanzibar.

BACKGROUND: Reactive case detection (RCD) is a commonly used strategy for malaria surveillance and response in elimination settings. Many approaches to RCD assume detectable infections are clustered within and around homes of passively detected cases (index households), which has been evaluated in a number of settings with disparate results. METHODS: Household questionnaires and diagnostic testing were conducted following RCD investigations in Zanzibar, Tanzania, including the index household and up to 9 additional neighboring households. RESULTS: Of 12,487 participants tested by malaria rapid diagnostic test (RDT), 3·2% of those residing in index households and 0·4% of those residing in non-index households tested positive (OR = 8·4; 95%CI: 5·7, 12·5). Of 6,281 participants tested by quantitative polymerase chain reaction (qPCR), 8·4% of those residing in index households and 1·3% of those residing in non-index households tested positive (OR = 7·1; 95%CI: 6·1, 10·9). Within households of index cases defined as imported, odds of qPCR-positivity amongst members reporting recent travel were 1·4 times higher than among those without travel history (95%CI: 0·2, 4·4). Amongst non-index households, odds of qPCR-detectable infection were no different between households located within 50 m of the index household as compared with those located farther away (OR = 0·8, 95%CI: 0·5, 1·4). Sensitivity of RDT to detect qPCR-detectable infections was 34% (95%CI: 26·4, 42·3). CONCLUSIONS: Malaria prevalence in index households in Zanzibar is much higher than in non-index households, in which prevalence is very low. Travelers represent a high-risk population. Low sensitivity of RDTs due to a high prevalence of low-density infections results in an RCD system missing a large proportion of the parasite reservoir.

The Association Between Cardiac Rehabilitation Attendance and Hospital Readmission.

Purpose: Cardiac rehabilitation is associated with improved clinical outcomes, but the impact of individual cardiac rehabilitation sessions on readmission rates is less studied. Methods: A retrospective evaluation of the relationship between the number of cardiac rehabilitation sessions completed and all-cause and cardiac readmission rates at 1 year was conducted. The 1-year cardiac readmission counts were modeled via Poisson regression. Results: Of the 347 patients included in the primary analysis, 227 (65%) completed all assigned cardiac rehabilitation sessions. At 1 year, 135 patients (39%) had at least 1 cardiac readmission, and 155 patients (45%) had at least 1 all-cause readmission. The primary result was that every additional cardiac rehabilitation session completed was associated with a 1.75% lower incidence rate of 1-year cardiac readmission (P = .01) and a 2% lower incidence rate of all-cause hospital readmission (P = .001). Conclusion: Regardless of the number of cardiac rehabilitation sessions assigned, each additional session attended was associated with reduced cardiac readmission by 1.75% and all-cause readmission by 2%.

Can school-based distribution be used to maintain coverage of long-lasting insecticide treated bed nets: evidence from a large scale programme in southern Tanzania?

Many sub-Saharan African countries have achieved substantial gains in insecticide treated bednet coverage since 2005. The Tanzania National Malaria Control Programme identified school-based net distribution as one potential 'keep-up' strategy for the purpose of maintaining long-lasting insecticidal net (LLIN) coverage after a nationwide mass campaign in 2011. The School Net Programme (SNP) was implemented in three regions of southern Tanzania and distributed one LLIN to each enrolled child attending schools in primary grades (standards) 1, 3, 5 and 7, and secondary grades (forms) 2 and 4 in 2013 and again with slightly modified eligibility criteria in 2014 and 2015. Household surveys in the programme area as well as in a control area were conducted after each of the SNP distributions to measure ownership and use of long-lasting insecticide treated nets. Ownership of at least one LLIN after the first distribution was 76.1% (95% CI 70.8-80.7) in the intervention area and 78.6% (95% CI 74.4-82.3) in the control area. After the second distribution, ownership of at least one LLIN had dropped significantly in the control area to 65.4% (95% CI 59.5-71.0) in 2015 (P < 0.001), while coverage in the intervention area was maintained at 79.3% (95% CI 75.4 × 82.6). Ownership of at least one LLIN in intervention area remained stable following the second round of net distribution. During the same period LLIN ownership, especially of enough nets to ensure all household member access, fell significantly in the control area. These results demonstrate that the SNP may be sufficient to maintain stable LLIN coverage following a mass distribution of LLINs.

Routine cognitive screening in a neurology practice: Effect on physician behavior.

BACKGROUND: Alzheimer disease is one of the most prevalent and costly neurologic disorders. American Academy of Neurology guidelines call for diagnosis and treatment when dementia is present, but provide no specific instruction relating to cognitive screening. METHODS: Our center piloted a cognitive screening initiative using the Mini-Cog, which was administered to all neurology patients aged ≥70 years without a history of a cognitive disorder. RESULTS: There was a 37.4% screen positive rate on the Mini-Cog. The percentage of patients with subjective memory complaints did not differ between patients screening positive vs negative on the Mini-Cog. Prospective analysis over an 18-month postscreening period showed that individuals screening positive for cognitive impairment were 10 times more likely to have follow-up cognitive assessment by the provider (p < 0.0001), almost 3 times more likely to be referred for neuropsychological testing (p = 0.003), and 3 times more likely to receive a diagnosis of cognitive impairment or dementia (p < 0.0001) compared to those screening negative. Diagnosis of a cognitive disorder, referral to a cognitive specialty clinician, and prescription of cognitive-enhancing medications were no more frequent than was observed in a randomized trial of screening in primary care, and evidence of neurologists' actions relevant to cognitive impairment was found in a minority of individuals screening positive. CONCLUSION: Further studies are needed to better understand factors influencing neurologist actions in the evaluation and treatment of cognitive impairment.