Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

Background: Globally cryptosporidiosis is one of the commonest causes of mortality in children under 24 months old and may be associated with important longterm health effects. Whilst most strains of Cryptosporidium parvum are zoonotic, C. parvum IIc is almost certainly anthroponotic. The global distribution of this potentially important emerging infection is not clear. Methods: We conducted a systematic review of papers identifying the subtype distribution of C. parvum infections globally. We searched PubMed and Scopus using the following key terms Cryptospor* AND parvum AND (genotyp* OR subtyp* OR gp60). Studies were eligible for inclusion if they had found C. parvum within their human study population and had subtyped some or all of these samples using standard gp60 subtyping. Pooled analyses of the proportion of strains being of the IIc subtype were determined using StatsDirect. Meta-regression analyses were run to determine any association between the relative prevalence of IIc and Gross Domestic Product, proportion of the population with access to improved drinking water and improved sanitation. Results: From an initial 843 studies, 85 were included in further analysis. Cryptosporidium parvum IIc was found in 43 of these 85 studies. Across all studies the pooled estimate of relative prevalence of IIc was 19.0% (95% CI: 12.9–25.9%), but there was substantial heterogeneity. In a meta-regression analysis, the relative proportion of all C. parvum infections being IIc decreased as the percentage of the population with access to improved sanitation increased and was some 3.4 times higher in those studies focussing on HIV-positive indivduals. Conclusions: The anthroponotic C. parvum IIc predominates primarily in lower-income countries with poor sanitation and in HIV-positive individuals. Given the apparent enhanced post-infectious virulence of the other main anthroponotic species of Cryptosporidium (C. hominis), it is important to learn about the impact of this subtype on human health

Anthroponotic transmission of Cryptosporidium parvum predominates in countries with poorer sanitation - a systematic review and meta-analysis

Background: Globally cryptosporidiosis is one of the commonest causes of mortality in children under 24 months old and may be associated with important longterm health effects. Whilst most strains of Cryptosporidium parvum are zoonotic, C. parvum IIc is almost certainly anthroponotic. The global distribution of this potentially important emerging infection is not clear. Methods: We conducted a systematic review of papers identifying the subtype distribution of C. parvum infections globally. We searched PubMed and Scopus using the following key terms Cryptospor* AND parvum AND (genotyp* OR subtyp* OR gp60). Studies were eligible for inclusion if they had found C. parvum within their human study population and had subtyped some or all of these samples using standard gp60 subtyping. Pooled analyses of the proportion of strains being of the IIc subtype were determined using StatsDirect. Meta-regression analyses were run to determine any association between the relative prevalence of IIc and Gross Domestic Product, proportion of the population with access to improved drinking water and improved sanitation. Results: From an initial 843 studies, 85 were included in further analysis. Cryptosporidium parvum IIc was found in 43 of these 85 studies. Across all studies the pooled estimate of relative prevalence of IIc was 19.0% (95% CI: 12.9–25.9%), but there was substantial heterogeneity. In a meta-regression analysis, the relative proportion of all C. parvum infections being IIc decreased as the percentage of the population with access to improved sanitation increased and was some 3.4 times higher in those studies focussing on HIV-positive indivduals. Conclusions: The anthroponotic C. parvum IIc predominates primarily in lower-income countries with poor sanitation and in HIV-positive individuals. Given the apparent enhanced post-infectious virulence of the other main anthroponotic species of Cryptosporidium (C. hominis), it is important to learn about the impact of this subtype on human health

The pregnant women as a drug orphan: a global survey of registered clinical trials of pharmacological interventions in pregnancy

Objective: To undertake a survey of the world's clinical trial registries to provide current data on the number, nature, funding source and geographical distribution of pregnancy drug trials (PDT). Design and setting: Comprehensive analysis of WHO-certified clinical trial registries. Methods Sixteen registries containing 301 538 trials (168 826 active in 2013–2014) were analysed to identify the numbers, location, funding sources, and areas of interest/development of PDTs. Results: The percentage of PDTs varied from 0 to 7.4% across registries. Overall, just 0.32% (534) of all active registered studies were PDTs. The US registry (Clinicaltrials.gov) was the largest database, but contributed just 14% of all active PDTs. The majority of PDTs focused on anaesthesia/analgesia, preterm birth/tocolysis, labour induction, endocrine and hypertensive disorders. Less than 6% of active PDTs focused on maternal or fetal health as a specific primary outcome, and only 4.4% included a preplanned pharmacokinetic analysis of the trial medications. A third of all active PDTs involved repurposing of existing medicines for applications in pregnancy, whereas only three new investigational drugs had been developed for a pregnancy indication. Seven percent of all active PDTs identified were pharmaceutical industry-funded. Inter-disease comparisons identified a ~50-fold disparity in trial activity between pregnancy and other comparable areas. Conclusions: This study demonstrates unequivocally the marked under-representation of medication development, evaluation and safety trials in pregnancy. The likelihood that the current pharmaceutical landscape in pregnancy will improve in the foreseeable future is slim. Advocacy and increased awareness of the issue is necessary to achieve positive change. Tweetable abstract: Pregnant women are significantly under-represented in global clinical drug trials.J Scaffidi, B W Mol, J A Keela