Abstract:
BACKGROUND:In the last decade, several epidemiological studies have demonstrated the potential of using seroprevalence (SP) and seroconversion rate (SCR) as informative indicators of malaria burden in low transmission settings or in populations on the cusp of elimination. However, most of studies are designed to control ensuing statistical inference over parasite rates and not on these alternative malaria burden measures. SP is in essence a proportion and, thus, many methods exist for the respective sample size determination. In contrast, designing a study where SCR is the primary endpoint, is not an easy task because precision and statistical power are affected by the age distribution of a given population. METHODS:Two sample size calculators for SCR estimation are proposed. The first one consists of transforming the confidence interval for SP into the corresponding one for SCR given a known seroreversion rate (SRR). The second calculator extends the previous one to the most common situation where SRR is unknown. In this situation, data simulation was used together with linear regression in order to study the expected relationship between sample size and precision. RESULTS:The performance of the first sample size calculator was studied in terms of the coverage of the confidence intervals for SCR. The results pointed out to eventual problems of under or over coverage for sample sizes ≤250 in very low and high malaria transmission settings (SCR ≤ 0.0036 and SCR ≥ 0.29, respectively). The correct coverage was obtained for the remaining transmission intensities with sample sizes ≥ 50. Sample size determination was then carried out for cross-sectional surveys using realistic SCRs from past sero-epidemiological studies and typical age distributions from African and non-African populations. For SCR < 0.058, African studies require a larger sample size than their non-African counterparts in order to obtain the same precision. The opposite happens for the remaining transmission intensities. With respect to the second sample size calculator, simulation unravelled the likelihood of not having enough information to estimate SRR in low transmission settings (SCR ≤ 0.0108). In that case, the respective estimates tend to underestimate the true SCR. This problem is minimized by sample sizes of no less than 500 individuals. The sample sizes determined by this second method highlighted the prior expectation that, when SRR is not known, sample sizes are increased in relation to the situation of a known SRR. In contrast to the first sample size calculation, African studies would now require lesser individuals than their counterparts conducted elsewhere, irrespective of the transmission intensity. CONCLUSIONS:Although the proposed sample size calculators can be instrumental to design future cross-sectional surveys, the choice of a particular sample size must be seen as a much broader exercise that involves weighting statistical precision with ethical issues, available human and economic resources, and possible time constraints. Moreover, if the sample size determination is carried out on varying transmission intensities, as done here, the respective sample sizes can also be used in studies comparing sites with different malaria transmission intensities. In conclusion, the proposed sample size calculators are a step towards the design of better sero-epidemiological studies. Their basic ideas show promise to be applied to the planning of alternative sampling schemes that may target or oversample specific age groups.
journal_name
Malar Jjournal_title
Malaria journalauthors
Sepúlveda N,Drakeley Cdoi
10.1186/s12936-015-0661-zsubject
Has Abstractpub_date
2015-04-03 00:00:00pages
141issn
1475-2875pii
10.1186/s12936-015-0661-zjournal_volume
14pub_type
杂志文章相关文献
MALARIA JOURNAL文献大全abstract:BACKGROUND:Artemisinin-based combination therapy is the first-line anti-malarial treatment for uncomplicated Plasmodium falciparum infection in Angola. To date, the prevalence of polymorphisms in the pfk13 gene, associated with artemisinin resistance, and pfmdr1, associated with lumefantrine resistance, have not been s...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-018-2233-5
更新日期:2018-02-20 00:00:00
abstract::Recent WHO guidelines recommend a universal "test and treat" strategy for malaria, mainly by use of rapid diagnostic test (RDT) in all areas. The evidence for this approach is questioned here as there is a risk of over-reliance on parasitological diagnosis in high transmission situations, which still exist. In such ar...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-10-136
更新日期:2011-05-20 00:00:00
abstract:BACKGROUND:The pro-inflammatory S100 calcium binding protein A8 (S100A8) is elevated in the serum of patients with Plasmodium falciparum malaria, but its function in Plasmodium vivax malaria is not yet clear. This function was investigated in P. vivax-infected patients in this study. METHODS:The level of S100A8 in the...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-015-0855-4
更新日期:2015-10-05 00:00:00
abstract:BACKGROUND:Saglin, a 100 kDa protein composed of two 50 kDa homodimers, is present in the salivary glands of Anopheles gambiae and has been considered an essential receptor for sporozoites (SPZ) of Plasmodium berghei and Plasmodium falciparum (Pf), allowing SPZ to recognize, bind to, and infect mosquito salivary glands...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-018-2634-5
更新日期:2019-01-03 00:00:00
abstract:BACKGROUND:Plasmodium falciparum malaria is a significant problem around the world today, thus there is still a need for new control methods to be developed. Because the sporozoite displays dual infectivity for both the mosquito salivary glands and vertebrate host tissue, it is a good target for vaccine development. M...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-11-80
更新日期:2012-03-23 00:00:00
abstract:BACKGROUND:Community-based service delivery is vital to the effectiveness, affordability and sustainability of vector control generally, and to labour-intensive larval source management (LSM) programmes in particular. CASE DESCRIPTION:The institutional evolution of a city-level, community-based LSM programme over 14 y...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-13-245
更新日期:2014-06-25 00:00:00
abstract:BACKGROUND:Understanding spatio-temporal variation in malaria incidence provides a basis for effective disease control planning and monitoring. METHODS:Monthly surveillance data between 1991 and 2006 for Plasmodium vivax and Plasmodium falciparum malaria across 128 counties were assembled for Yunnan, a province of Chi...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-8-180
更新日期:2009-07-31 00:00:00
abstract:BACKGROUND:The use of anti-malarial drug combinations with artemisinin or with one of its derivatives is now widely recommended to overcome drug resistance in falciparum as well as vivax malaria. The fixed oral dose artemisinin-naphthoquine combination (ANQ, ARCO) is a newer artemisinin-based combination (ACT) therapy ...
journal_title:Malaria journal
pub_type: 杂志文章,随机对照试验
doi:10.1186/1475-2875-8-196
更新日期:2009-08-12 00:00:00
abstract:BACKGROUND:Inter-individual variability in plasma concentration-time profiles might contribute to differences in anti-malarial treatment response. This study investigated the pharmacokinetics of three different forms of artemisinin combination therapy (ACT) in Tanzania and Cambodia to quantify and identify potential so...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-12-235
更新日期:2013-07-10 00:00:00
abstract:BACKGROUND:Relatively few programmes have attempted to actively engage the private sector in national malaria control efforts. This paper evaluates the health impact of a large-scale distribution of insecticide-treated nets (ITNs) conducted in partnership with a Zambian agribusiness, and its cost-effectiveness from the...
journal_title:Malaria journal
pub_type: 杂志文章,随机对照试验
doi:10.1186/1475-2875-12-102
更新日期:2013-03-18 00:00:00
abstract:BACKGROUND:Information is needed on the expected durability of insecticidal nets under operational conditions. The persistence of insecticidal efficacy is important to estimate the median serviceable life of nets under field conditions and to plan for net replacement. METHODS:Deltamethrin residue levels were evaluated...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-13-80
更新日期:2014-03-06 00:00:00
abstract:BACKGROUND:In 2017, nearly 80% of malaria morbidity and mortality occurred in sub-Saharan African (SSA) countries and India. Rapid diagnostic tests (RDTs), especially those targeting histidine-rich protein 2 (PfHRP2) of Plasmodium falciparum, have become an important diagnostic tool in these malaria-endemic areas. Howe...
journal_title:Malaria journal
pub_type: 杂志文章,meta分析
doi:10.1186/s12936-019-3090-6
更新日期:2020-01-28 00:00:00
abstract:BACKGROUND:There is evidence that suggests that undernutrition has a detrimental effect on malarial immunity in children. The aim of the study was to discover whether nutrient supplementation improved development of malarial antibody immunity in children up to 18 months of age. METHODS:The study was conducted with a s...
journal_title:Malaria journal
pub_type: 杂志文章,随机对照试验
doi:10.1186/s12936-018-2224-6
更新日期:2018-02-07 00:00:00
abstract:BACKGROUND:Understanding the dynamics of malaria transmission in diverse endemic settings is key for designing and implementing locally adapted and sustainable control and elimination strategies. A parasitological and epidemiological survey was conducted in September-October 2012, as a baseline underlying a 3-year popu...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-017-1957-y
更新日期:2017-08-04 00:00:00
abstract::The hypnozoite reservoir of Plasmodium vivax represents both the greatest obstacle and opportunity for ultimately eradicating this species. It is silent and cannot be diagnosed until it awakens and provokes a clinical attack with attendant morbidity, risk of mortality, and opportunities for onward transmission. The on...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-018-2190-z
更新日期:2018-01-22 00:00:00
abstract:BACKGROUND:Behaviour change communication (BCC) can improve malaria prevention and treatment behaviour. As a one of the activities under Myanmar Artemisinin Resistance Containment (MARC) programme, BCC have been conducting. This study aimed to evaluate the effectiveness of the behaviour change communication and communi...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-015-1047-y
更新日期:2015-12-23 00:00:00
abstract:BACKGROUND:Plasmodium ovale, considered the rarest of the malaria parasites of humans, consists of two morphologically identical but genetically distinct sympatric species, Plasmodium ovale curtisi and Plasmodium ovale wallikeri. These parasites resemble morphologically to Plasmodium vivax with which they also share a ...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-015-0985-8
更新日期:2015-11-14 00:00:00
abstract:BACKGROUND:The clinical presentation of malaria, considered as the result of a complex interaction between parasite and human genetics, is described to be different between rural and urban areas. The analysis of the Plasmodium falciparum genetic diversity in children with uncomplicated malaria, living in these two diff...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-8-135
更新日期:2009-06-20 00:00:00
abstract:BACKGROUND:Acute kidney injury (AKI) is a common complication of malaria. In low resource settings, a lack of diagnostic tools and delayed treatment of malaria associated AKI lead to significant morbidity and mortality. The aim of this study was to assess the diagnostic performance of salivary urea nitrogen (SUN) dipst...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-018-2627-4
更新日期:2018-12-18 00:00:00
abstract:BACKGROUND:In 2001, the World Health Organization (WHO) has recommended the use of artemisinin-based combination therapy (ACT) as the first-line treatment of uncomplicated malaria cases, as monotherapies had become ineffective in many parts of the world. As a result, the Democratic Republic of Congo (DRC) withdrew chlo...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-12-459
更新日期:2013-12-20 00:00:00
abstract:BACKGROUND:Several anti-malarial drugs are associated with adverse cardiovascular effects. These effects may be exacerbated when different anti-malarials are used in combination. There has been no report yet on the potential cardiac effects of the combination artesunate-amodiaquine. METHODS:Electrocardiographic (ECG) ...
journal_title:Malaria journal
pub_type: 临床试验,杂志文章
doi:10.1186/1475-2875-11-420
更新日期:2012-12-17 00:00:00
abstract:BACKGROUND:The number of clinical cases of malaria is often recorded in resource constrained or conflict settings as a proxy for disease burden. Interpreting case count data in areas of humanitarian need is challenging due to uncertainties in population size caused by security concerns, resource constraints and populat...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-018-2460-9
更新日期:2018-08-29 00:00:00
abstract:BACKGROUND:Immunization with attenuated malaria sporozoites protects humans from experimental malaria challenge by mosquito bite. Protection in humans is strongly correlated with the production of T cells targeting a heterogeneous population of pre-erythrocyte antigen proteoforms, including liver stage antigens. Curren...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-019-3093-3
更新日期:2020-01-07 00:00:00
abstract:BACKGROUND:Transmission of malaria from man to mosquito depends on the presence of gametocytes, the sexual stage of Plasmodium parasites in the infected host. Naturally acquired antibodies against gametocytes exist and may play a role in controlling transmission by limiting the gametocyte development in the circulation...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-017-1827-7
更新日期:2017-04-26 00:00:00
abstract:BACKGROUND:The malaria rapid diagnostic tests (RDTs) are now widely used in the world. Compared to Plasmodium falciparum, a poor sensitivity of RDTs was reported against Plasmodium vivax based on the adopted antibody against pan-Plasmodium antigen lactate dehydrogenase (pLDH) or aldolase. Levels of pLDH were measured f...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-12-181
更新日期:2013-06-03 00:00:00
abstract:BACKGROUND:Asymptomatic carriage of Plasmodium falciparum is widespread in adults and children living in malaria-endemic countries. This study identified the prevalence of malaria parasites and the corresponding levels of naturally acquired anti-parasite antibody levels in afebrile adults living in two communities in t...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-020-3146-7
更新日期:2020-02-10 00:00:00
abstract:BACKGROUND:Plasmodium vivax is very rarely seen in West Africa, although specific detection methods are not widely applied in the region, and it is now considered to be absent from North Africa. However, this parasite species has recently been reported to account for most malaria cases in Nouakchott, the capital of Mau...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/s12936-016-1118-8
更新日期:2016-02-09 00:00:00
abstract:BACKGROUND:Intermittent preventive treatment with sulphadoxine-pyrimethamine (IPT-SP) is currently the recommended regimen for prevention of malaria in pregnancy in endemic areas. This study sets out to evaluate the effectiveness of IPT-SP in the prevention of maternal and placental malaria in parturient mothers in Iba...
journal_title:Malaria journal
pub_type: 临床试验,杂志文章
doi:10.1186/1475-2875-6-88
更新日期:2007-07-06 00:00:00
abstract:BACKGROUND:The Plasmodium falciparum protein RH5 is an adhesin molecule essential for parasite invasion of erythrocytes. Recent studies show that anti-PfRH5 sera have potent invasion-inhibiting activities, supporting the idea that the PfRH5 antigen could form the basis of a vaccine. Therefore, epitopes recognized by ne...
journal_title:Malaria journal
pub_type: 杂志文章
doi:10.1186/1475-2875-13-326
更新日期:2014-08-18 00:00:00
abstract:BACKGROUND:The circumsporozoite protein (CS protein) on the malaria parasites in mosquitoes plays an important role in sporogony in mosquitoes. The RTS,S/AS01 malaria vaccine candidate, which has shown significant efficacy against clinical malaria in a large Phase 3 trial, targets the Plasmodium falciparum CS protein, ...
journal_title:Malaria journal
pub_type: 杂志文章,多中心研究
doi:10.1186/1475-2875-13-263
更新日期:2014-07-09 00:00:00