scholarly journals The secondary transmission pattern of COVID-19 based on contact tracing in Rwanda

2021 ◽  
Vol 6 (6) ◽  
pp. e004885
Author(s):  
Muhammed Semakula ◽  
FranÇois Niragire ◽  
Angela Umutoni ◽  
Sabin Nsanzimana ◽  
Vedaste Ndahindwa ◽  
...  
Keyword(s):  
Risk Factors ◽  
High Risk ◽  
Disease Transmission ◽  
Index Case ◽  
Conditional Logistic Regression ◽  
Contact Tracing ◽  
African Countries ◽  
Targeted Interventions ◽  
The Impact ◽  
Mapping Models

IntroductionCOVID-19 has shown an exceptionally high spread rate across and within countries worldwide. Understanding the dynamics of such an infectious disease transmission is critical for devising strategies to control its spread. In particular, Rwanda was one of the African countries that started COVID-19 preparedness early in January 2020, and a total lockdown was imposed when the country had only 18 COVID-19 confirmed cases known. Using intensive contact tracing, several infections were identified, with the majority of them being returning travellers and their close contacts. We used the contact tracing data in Rwanda for understanding the geographic patterns of COVID-19 to inform targeted interventions.MethodsWe estimated the attack rates and identified risk factors associated to COVID-19 spread. We used Bayesian disease mapping models to assess the spatial pattern of COVID-19 and to identify areas characterised by unusually high or low relative risk. In addition, we used multiple variable conditional logistic regression to assess the impact of the risk factors.ResultsThe results showed that COVID-19 cases in Rwanda are localised mainly in the central regions and in the southwest of Rwanda and that some clusters occurred in the northeast of Rwanda. Relationship to the index case, being male and coworkers are the important risk factors for COVID-19 transmission in Rwanda.ConclusionThe analysis of contact tracing data using spatial modelling allowed us to identify high-risk areas at subnational level in Rwanda. Estimating risk factors for infection with SARS-CoV-2 is vital in identifying the clusters in low spread of SARS-CoV-2 subnational level. It is imperative to understand the interactions between the index case and contacts to identify superspreaders, risk factors and high-risk places. The findings recommend that self-isolation at home in Rwanda should be reviewed to limit secondary cases from the same households and spatiotemporal analysis should be introduced in routine monitoring of COVID-19 in Rwanda for policy making decision on real time.

scholarly journals Rotavirus disease burden pre-vaccine introduction in young children in Rural Southern Mozambique, an area of high HIV prevalence

PLoS ONE ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. e0249714
Author(s):  
Sozinho Acácio ◽  
Tacilta Nhampossa ◽  
Llorenç Quintò ◽  
Delfino Vubil ◽  
Marcelino Garrine ◽  
...  
Keyword(s):  
Risk Factors ◽  
Disease Burden ◽  
Conditional Logistic Regression ◽  
Epidemiological Data ◽  
Daily Basis ◽  
African Countries ◽  
Severe Diarrhea ◽  
Vaccine Introduction ◽  
Rotavirus Vaccines ◽  
The Impact

Background Rotavirus vaccines have been adopted in African countries since 2009, including Mozambique (2015). Disease burden data are needed to evaluate the impact of rotavirus vaccine. We report the burden of rotavirus-associated diarrhea in Mozambique from the Global Enteric Multicenter Study (GEMS) before vaccine introduction. Methods A case-control study (GEMS), was conducted in Manhiça district, recruiting children aged 0–59 months with moderate-to-severe diarrhea (MSD) and less-severe-diarrhea (LSD) between December 2007 and November 2012; including 1–3 matched (age, sex and neighborhood) healthy community controls. Clinical and epidemiological data and stool samples (for laboratory investigation) were collected. Association of rotavirus with MSD or LSD was determined by conditional logistic regression and adjusted attributable fractions (AF) calculated, and risk factors for rotavirus diarrhea assessed. Results Overall 915 cases and 1,977 controls for MSD, and 431 cases and 430 controls for LSD were enrolled. Rotavirus positivity was 44% (217/495) for cases and 15% (160/1046) of controls, with AF = 34.9% (95% CI: 32.85–37.06) and adjusted Odds Ratio (aOR) of 6.4 p< 0.0001 in infants with MSD compared to 30% (46/155) in cases and 14% (22/154) in controls yielding AF = 18.7%, (95% CI: 12.02–25.39) and aOR = 2.8, p = 0.0011 in infants with LSD. The proportion of children with rotavirus was 32% (21/66) among HIV-positive children and 23% (128/566) among HIV-negative ones for MSD. Presence of animals in the compound (OR = 1.9; p = 0.0151) and giving stored water to the child (OR = 2.0, p = 0.0483) were risk factors for MSD; while animals in the compound (OR = 2.37, p = 0.007); not having routine access to water on a daily basis (OR = 1.53, p = 0.015) and washing hands before cooking (OR = 1.76, p = 0.0197) were risk factors for LSD. Conclusion The implementation of vaccination against rotavirus may likely result in a significant reduction of rotavirus-associated diarrhea, suggesting the need for monitoring of vaccine impact.

scholarly journals Estimating the burden of cardiovascular risk in community dwellers over 40 years old in South Africa, Kenya, Burkina Faso and Ghana

2021 ◽  
Vol 6 (1) ◽  
pp. e003499
Author(s):  
Ryan G Wagner ◽  
Nigel J Crowther ◽  
Lisa K Micklesfield ◽  
Palwende Romauld Boua ◽  
Engelbert A Nonterah ◽  
...  
Keyword(s):  
Risk Factors ◽  
Risk Factor ◽  
South African ◽  
Sub Saharan Africa ◽  
African Countries ◽  
Cvd Risk ◽  
Genomic Studies ◽  
Sub Saharan ◽  
Context Specific ◽  
The Impact

IntroductionCardiovascular disease (CVD) risk factors are increasing in sub-Saharan Africa. The impact of these risk factors on future CVD outcomes and burden is poorly understood. We examined the magnitude of modifiable risk factors, estimated future CVD risk and compared results between three commonly used 10-year CVD risk factor algorithms and their variants in four African countries.MethodsIn the Africa-Wits-INDEPTH partnership for Genomic studies (the AWI-Gen Study), 10 349 randomly sampled individuals aged 40–60 years from six sites participated in a survey, with blood pressure, blood glucose and lipid levels measured. Using these data, 10-year CVD risk estimates using Framingham, Globorisk and WHO-CVD and their office-based variants were generated. Differences in future CVD risk and results by algorithm are described using kappa and coefficients to examine agreement and correlations, respectively.ResultsThe 10-year CVD risk across all participants in all sites varied from 2.6% (95% CI: 1.6% to 4.1%) using the WHO-CVD lab algorithm to 6.5% (95% CI: 3.7% to 11.4%) using the Framingham office algorithm, with substantial differences in risk between sites. The highest risk was in South African settings (in urban Soweto: 8.9% (IQR: 5.3–15.3)). Agreement between algorithms was low to moderate (kappa from 0.03 to 0.55) and correlations ranged between 0.28 and 0.70. Depending on the algorithm used, those at high risk (defined as risk of 10-year CVD event >20%) who were under treatment for a modifiable risk factor ranged from 19.2% to 33.9%, with substantial variation by both sex and site.ConclusionThe African sites in this study are at different stages of an ongoing epidemiological transition as evidenced by both risk factor levels and estimated 10-year CVD risk. There is low correlation and disparate levels of population risk, predicted by different risk algorithms, within sites. Validating existing risk algorithms or designing context-specific 10-year CVD risk algorithms is essential for accurately defining population risk and targeting national policies and individual CVD treatment on the African continent.

scholarly journals STIGMA-STATISTIK: Når dagsordener sættes i dansk aids-politik

1996 ◽  
Author(s):  
Jens Seeberg
Keyword(s):  
Human Rights ◽  
Hiv Testing ◽  
Asylum Seekers ◽  
Negative Impact ◽  
Public Debate ◽  
Contact Tracing ◽  
Infected Person ◽  
African Countries ◽  
Aids Policy ◽  
The Impact

Jens Seeberg: Stigma Statistics: Agendas in the Making in Danish AIDS Policy This article explores a number of paradoxes and assumptions in the public debate on AIDS in Denmark. They form part of a recurrent attack on the Danish ‘soft line’ AIDS policy that maintains anonymity and voluntary HIV-testing. One central issue in recent years has been obligatory testing of asylum seekers from high risk areas as a precondition for considering the asylum request. Especially asylum seekers from African countries are pointed out as constituting a major threat to the native Danish population in terms of spread of HIV. This is shown to rest on a misreading of the official statistics, repeated as often as the statistics themselves. The assumption that there is a basic clash between the human rights of the HIV-infected person and the population in general is discussed. This conceived clash rests on the assumption that restrictions of the human rights of the HIV-infected person will provide efficient protection for the noninfected majority. The potential counterproductive effects of this line of thought are discussed. Contact tracing is sometimes considered as an effective preventive measure. Part of the critique of the present AIDS policy States that contact tracing is virtually non-existing and that this has a major negative impact on the preventive efforts. It is argued that while the impact of contact tracing in itself may be rather limited, the lack of contact tracing may be seen as a symptom of insufficient counselling. While obligatory HIV testing may never be practiced in Denmark, its recurrent appearance on the agenda serves to provoke a defensive stand among AIDS policy makers. It is argued that this debate has hitherto had the effect of keeping the needs of HIV-infected people - and especially HIV-infected immigrants — away from public debate and serious concern.

scholarly journals Modeling the impact of school reopening and contact tracing strategies on Covid-19 dynamics in different epidemiologic settings in Brazil

2021 ◽  
Author(s):  
Marcelo Eduardo Borges ◽  
Leonardo Souto Ferreira ◽  
Silas Poloni ◽  
Ângela Maria Bagattini ◽  
Caroline Franco ◽  
...  
Keyword(s):  
Disease Transmission ◽  
Transmission Rate ◽  
Disease Incidence ◽  
Demographic Data ◽  
School Closure ◽  
Mitigation Measures ◽  
Contact Tracing ◽  
School Closures ◽  
Infection Transmission ◽  
The Impact

Among the various non–pharmaceutical interventions implemented in response to the Covid–19 pandemic during 2020, school closures have been in place in several countries to reduce infection transmission. Nonetheless, the significant short and long–term impacts of prolonged suspension of in–person classes is a major concern. There is still considerable debate around the best timing for school closure and reopening, its impact on the dynamics of disease transmission, and its effectiveness when considered in association with other mitigation measures. Despite the erratic implementation of mitigation measures in Brazil, school closures were among the first measures taken early in the pandemic in most of the 27 states in the country. Further, Brazil delayed the reopening of schools and stands among the countries in which schools remained closed for the most prolonged period in 2020. To assess the impact of school reopening and the effect of contact tracing strategies in rates of Covid–19 cases and deaths, we model the epidemiological dynamics of disease transmission in 3 large urban centers in Brazil under different epidemiological contexts. We implement an extended SEIR model stratified by age and considering contact networks in different settings – school, home, work, and elsewhere, in which the infection transmission rate is affected by various intervention measures. After fitting epidemiological and demographic data, we simulate scenarios with increasing school transmission due to school reopening. Our model shows that reopening schools results in a non–linear increase of reported Covid-19 cases and deaths, which is highly dependent on infection and disease incidence at the time of reopening. While low rates of within[&ndash]school transmission resulted in small effects on disease incidence (cases/100,000 pop), intermediate or high rates can severely impact disease trends resulting in escalating rates of new cases even if other interventions remain unchanged. When contact tracing and quarantining are restricted to school and home settings, a large number of daily tests is required to produce significant effects of reducing the total number of hospitalizations and deaths. Our results suggest that policymakers should carefully consider the epidemiological context and timing regarding the implementation of school closure and return of in-person school activities. Also, although contact tracing strategies are essential to prevent new infections and outbreaks within school environments, our data suggest that they are alone not sufficient to avoid significant impacts on community transmission in the context of school reopening in settings with high and sustained transmission rates.

scholarly journals Impact of recent climate extremes on mosquito-borne disease transmission in Kenya

2021 ◽  
Vol 15 (3) ◽  
pp. e0009182
Author(s):  
Cameron Nosrat ◽  
Jonathan Altamirano ◽  
Assaf Anyamba ◽  
Jamie M. Caldwell ◽  
Richard Damoah ◽  
...  
Keyword(s):  
Climate Change ◽  
Disease Transmission ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mosquito Abundance ◽  
Targeted Interventions ◽  
Extreme Climate Events ◽  
Extreme Climate ◽  
Recent Climate ◽  
Climate Events ◽  
The Impact

Climate change and variability influence temperature and rainfall, which impact vector abundance and the dynamics of vector-borne disease transmission. Climate change is projected to increase the frequency and intensity of extreme climate events. Mosquito-borne diseases, such as dengue fever, are primarily transmitted by Aedes aegypti mosquitoes. Freshwater availability and temperature affect dengue vector populations via a variety of biological processes and thus influence the ability of mosquitoes to effectively transmit disease. However, the effect of droughts, floods, heat waves, and cold waves is not well understood. Using vector, climate, and dengue disease data collected between 2013 and 2019 in Kenya, this retrospective cohort study aims to elucidate the impact of extreme rainfall and temperature on mosquito abundance and the risk of arboviral infections. To define extreme periods of rainfall and land surface temperature (LST), we calculated monthly anomalies as deviations from long-term means (1983–2019 for rainfall, 2000–2019 for LST) across four study locations in Kenya. We classified extreme climate events as the upper and lower 10% of these calculated LST or rainfall deviations. Monthly Ae. aegypti abundance was recorded in Kenya using four trapping methods. Blood samples were also collected from children with febrile illness presenting to four field sites and tested for dengue virus using an IgG enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). We found that mosquito eggs and adults were significantly more abundant one month following an abnormally wet month. The relationship between mosquito abundance and dengue risk follows a non-linear association. Our findings suggest that early warnings and targeted interventions during periods of abnormal rainfall and temperature, especially flooding, can potentially contribute to reductions in risk of viral transmission.

The impact of multiple high-risk factors on survival outcome of surgically treated early-stage cervical cancer

2014 ◽  
Vol 133 ◽  
pp. 62
Author(s):  
K. Matsuo ◽  
S. Mabuchi ◽  
M. Okazawa ◽  
Y. Matsumoto ◽  
K. Yoshino ◽  
...  
Keyword(s):  
Risk Factors ◽  
Cervical Cancer ◽  
High Risk ◽  
Early Stage ◽  
Survival Outcome ◽  
High Risk Factors ◽  
Early Stage Cervical Cancer ◽  
The Impact

Second Primary Melanoma: Risk Factors, Histopathologic Features, Survival, and Implications for Follow-Up

2016 ◽  
Vol 82 (10) ◽  
pp. 1009-1013 ◽  
Author(s):  
Maris S. Jones ◽  
Hitoe Torisu-Itakura ◽  
Devin C. Flaherty ◽  
Hans F. Schoellhammer ◽  
Jihey Lee ◽  
...  
Keyword(s):  
Risk Factors ◽  
High Risk ◽  
Cutaneous Melanoma ◽  
Primary Melanoma ◽  
Second Primary ◽  
Melanoma Risk ◽  
Impact On Survival ◽  
The Impact ◽  
Histopathologic Features

The impact on survival of a second primary melanoma (SPM) is unclear. We used our melanoma center's database to examine clinicopathologic risk factors and outcomes of stage 0 to IV cutaneous melanoma in patients with one versus two primaries. Among 12,325 patients with primary melanoma, 969 (7.86%) developed SPM. SPMs were significantly thinner than autologous primary melanomas ( P = 0.01), and 451 SPM patients had better overall and melanoma-specific survival than 451 prognostically matched non-SPM patients ( P < 0.0001 and 0.0001, respectively) at a median follow-up of 142.37 months. Patients with cutaneous melanoma are at high risk for development of SPM, but the development of SPM does not seem to impair survival.

scholarly journals Identifying Risk Factors Of A(H7N9) Outbreak by Wavelet Analysis and Generalized Estimating Equation

2019 ◽  
Vol 16 (8) ◽  
pp. 1311
Author(s):  
Qinling Yan ◽  
Sanyi Tang ◽  
Zhen Jin ◽  
Yanni Xiao
Keyword(s):  
Risk Factors ◽  
Wavelet Analysis ◽  
Disease Transmission ◽  
Media Coverage ◽  
Meteorological Factors ◽  
Impact Factors ◽  
Observation Data ◽  
Time Frequency ◽  
The Impact ◽  
H7n9 Outbreak

Five epidemic waves of A(H7N9) occurred between March 2013 and May 2017 in China. However, the potential risk factors associated with disease transmission remain unclear. To address the spatial–temporal distribution of the reported A(H7N9) human cases (hereafter referred to as “cases”), statistical description and geographic information systems were employed. Based on long-term observation data, we found that males predominated the majority of A(H7N9)-infected individuals and that most males were middle-aged or elderly. Further, wavelet analysis was used to detect the variation in time-frequency between A(H7N9) cases and meteorological factors. Moreover, we formulated a Poisson regression model to explore the relationship among A(H7N9) cases and meteorological factors, the number of live poultry markets (LPMs), population density and media coverage. The main results revealed that the impact factors of A(H7N9) prevalence are manifold, and the number of LPMs has a significantly positive effect on reported A(H7N9) cases, while the effect of weekly average temperature is significantly negative. This confirms that the interaction of multiple factors could result in a serious A(H7N9) outbreak. Therefore, public health departments adopting the corresponding management measures based on both the number of LPMs and the forecast of meteorological conditions are crucial for mitigating A(H7N9) prevalence.

Modifying Pro-Drug Risk Factors in Adolescents: Results From Project ALERT

2004 ◽  
Vol 31 (3) ◽  
pp. 318-334 ◽  
Author(s):  
Bonnie Ghosh-Dastidar ◽  
Douglas L. Longshore ◽  
Phyllis L. Ellickson ◽  
Daniel F. McCaffrey
Keyword(s):  
Risk Factors ◽  
High Risk ◽  
Drug Use ◽  
Eighth Graders ◽  
Risk Groups ◽  
Drug Prevention ◽  
School Environments ◽  
School Based ◽  
Drug Risk ◽  
The Impact

The objective of this study was to evaluate the impact of a revised state-of-the-art drug prevention program, Project ALERT, on risk factors for drug use in mostly rural midwestern schools and communities. Fifty-five middle schools from South Dakota were randomly assigned to treatment or control conditions. Treatment-group students received 11 lessons in Grade 7 and 3 more in Grade 8. Effects for 4,276 eighth graders were assessed 18 months after baseline. Results indicate that Project ALERT had statistically significant effects on all the targeted risk factors associated with cigarette and marijuana use and more modest gains with the pro-alcoholrisk factors. The program helped adolescents at low, moderate, and high risk for future use, with the effect sizes typically stronger for the low- and moderate-risk groups. Thus, school-based drug prevention programs can lower risk factors that correlate with drug use, help low- to high-risk adolescents, and be effective in diverse school environments.

Sign in / Sign up

Export Citation Format

Share Document