Molecular Characterization of <i>Cryptosporidium spp</i>. among Children in Rural Ghana

<div><p>Background</p><p>The relevance of <i>Cryptosporidium</i> infections for the burden of childhood diarrhoea in endemic settings has been shown in recent years. This study describes <i>Cryptosporidium</i> subtypes among symptomatic and asymptomatic children in rural Ghana to analyse subtype-specific demographic, geographical, seasonal and clinical differences in order to inform appropriate control measures in endemic areas.</p><p>Methodology/Principal Findings</p><p>Stool samples were collected from 2232 children below 14 years of age presenting with and without gastrointestinal symptoms at the Agogo Presbyterian Hospital in the rural Ashanti region of Ghana between May 2007 and September 2008. Samples were screened for <i>Cryptosporidium spp</i>. by PCR and isolates were classified into subtypes based on sequence differences in the <i>gp60</i> gene. Subtype specific frequencies for age, sex, location and season have been determined and associations with disease symptoms have been analysed within a case-control study.</p><p><i>Cryptosporidium</i> infections were diagnosed in 116 of 2232 (5.2%) stool samples. Subtyping of 88 isolates revealed IIcA5G3 (n = 26, 29.6%), IbA13G3 (n = 17, 19.3%) and IaA21R3 (n = 12, 13.6%) as the three most frequent subtypes of the two species <i>C</i>. <i>hominis</i> and <i>C</i>. <i>parvum</i>, known to be transmitted anthroponotically. Infections peak at early rainy season with 67.9% and 50.0% of infections during the months April, May and June for 2007 and 2008 respectively. <i>C</i>. <i>hominis</i> infection was mainly associated with diarrhoea (odds ratio [OR] = 2.4; 95% confidence interval [CI]: 1.2–4.9) whereas <i>C</i>. <i>parvum</i> infection was associated with both diarrhoea (OR = 2.6; CI: 1.2–5.8) and vomiting (OR = 3.1; 95% CI: 1.5–6.1).</p><p>Conclusions/Significance</p><p>Cryptosporidiosis is characterized by seasonal anthroponotic transmission of strains typically found in Sub-Saharan Africa. The infection mainly affects young infants, with vomiting and diarrhoea being one of the leading symptoms in <i>C</i>. <i>parvum</i> infection. Combining molecular typing and clinical data provides valuable information for physicians and is able to track sources of infections.</p></div

Number of <i>Cryptosporidium parvum/homini</i>s cases by age and sex (n = 116).

<p>The majority of patients are below the age of three (87.1%, n = 101) years with 56.9% (n = 66) of cases being male. The mean age for male subjects (0.85; SD 0.90) is lower than for females (1.74; SD 2.36).</p

<i>Cryptosporidium parvum/hominis</i> and their association with gastrointestinal symptoms.

<p>OR: Age-adjusted odds ratios, with 95% confidence intervals (CI), calculated using the Mantel Haenszel method</p><p>^$for seven <i>Cryptosporidium spp</i>. positive children no clinical data was available.</p><p><i>Cryptosporidium parvum/hominis</i> and their association with gastrointestinal symptoms.</p

Distribution of Cryptosporidium subtypes (n = 88) and percentage of all study participants infected with Cryptosporidium spp. (n = 2,322) over the study period.

<p>The proportion of infected patients peak during rainy seasons from May to July 2007 and April to July 2008. No clusters of specific subtype families are observed over time.</p

Phylogenetic analysis.

<p>Phylogenetic analysis of <i>C</i>. <i>hominis</i> and <i>C</i>. <i>parvum</i> subtypes and six reference strains with their respective accession numbers using neighbour-joining analysis of the gylcoprotein 60 (<i>gp60</i>) gene. Values on branches are percentage bootstrap values using 1,000 replicates. Only bootstrap values greater than 50% are shown.</p

Gastrointestinal Infections and Diarrheal Disease in Ghanaian Infants and Children: An Outpatient Case-Control Study

<div><p>Introduction</p><p>Diarrheal diseases are among the most frequent causes of morbidity and mortality in children worldwide, especially in resource-poor areas. This case-control study assessed the associations between gastrointestinal infections and diarrhea in children from rural Ghana.</p><p>Methods</p><p>Stool samples were collected from 548 children with diarrhea and from 686 without gastrointestinal symptoms visiting a hospital from 2007–2008. Samples were analyzed by microscopy and molecular methods.</p><p>Results</p><p>The organisms most frequently detected in symptomatic cases were <i>Giardia lamblia</i>, <i>Shigella</i> spp./ enteroinvasive <i>Escherichia coli</i> (EIEC), and <i>Campylobacter jejuni</i>. Infections with rotavirus (adjusted odds ratio [aOR] = 8.4; 95% confidence interval [CI]: 4.3–16.6), <i>C</i>. <i>parvum/hominis</i> (aOR = 2.7; 95% CI: 1.4–5.2) and norovirus (aOR = 2.0; 95%CI: 1.3–3.0) showed the strongest association with diarrhea. The highest attributable fractions (AF) for diarrhea were estimated for rotavirus (AF = 14.3%; 95% CI: 10.9–17.5%), <i>Shigella</i> spp./EIEC (AF = 10.5%; 95% CI: 3.5–17.1%), and norovirus (AF = 8.2%; 95% CI 3.2–12.9%). Co-infections occurred frequently and most infections presented themselves independently of other infections. However, infections with <i>E</i>. <i>dispar</i>, <i>C</i>. <i>jejuni</i>, and norovirus were observed more often in the presence of <i>G</i>. <i>lamblia</i>.</p><p>Conclusions</p><p>Diarrheal diseases in children from a rural area in sub-Saharan Africa are mainly due to infections with rotavirus, <i>Shigella</i> spp./EIEC, and norovirus. These associations are strongly age-dependent, which should be considered when diagnosing causes of diarrhea. The presented results are informative for both clinicians treating gastrointestinal infections as well as public health experts designing control programs against diarrheal diseases.</p></div

Nasal Carriage of <i>Staphylococcus aureus</i> among Children in the Ashanti Region of Ghana

<div><p>Background</p><p>Nasal carriage with <i>Staphylococcus aureus</i> is a common risk factor for invasive infections, indicating the necessity to monitor prevalent strains, particularly in the vulnerable paediatric population. This surveillance study aims to identify carriage rates, subtypes, antimicrobial susceptibilities and virulence markers of nasal <i>S</i>. <i>aureus</i> isolates collected from children living in the Ashanti region of Ghana.</p><p>Methods</p><p>Nasal swabs were obtained from children < 15 years of age on admission to the Agogo Presbyterian Hospital between April 2014 and January 2015. <i>S</i>. <i>aureus</i> isolates were characterized by their antimicrobial susceptibility, the presence of genes encoding for Panton-Valentine leukocidin (PVL) and toxic shock syndrome toxin-1 (TSST-1) and further differentiated by <i>spa</i>-typing and multi-locus-sequence-typing.</p><p>Results</p><p>Out of 544 children 120 (22.1%) were colonized with <i>S</i>. <i>aureus</i>, with highest carriage rates during the rainy seasons (27.2%; p = 0.007), in females aged 6–8 years (43.7%) and males aged 8–10 years (35.2%). The 123 isolates belonged to 35 different <i>spa</i>-types and 19 sequence types (ST) with the three most prevalent <i>spa</i>-types being t355 (n = 25), t84 (n = 18), t939 (n = 13), corresponding to ST152, ST15 and ST45. Two (2%) isolates were methicillin-resistant <i>S</i>. <i>aureus</i> (MRSA), classified as t1096 (ST152) and t4454 (ST45), and 16 (13%) were resistant to three or more different antimicrobial classes. PVL and TSST-1 were detected in 71 (58%) and 17 (14%) isolates respectively.</p><p>Conclusion</p><p><i>S</i>. <i>aureus</i> carriage among Ghanaian children seems to depend on age, sex and seasonality. While MRSA rates are low, the high prevalence of PVL is of serious concern as these strains might serve not only as a source for severe invasive infections but may also transfer genes, leading to highly virulent MRSA clones.</p></div

Sensitivity analysis of equilibrium values for <i>H. pylori</i> infection (primary y-axes) and time to equilibrium (secondary y-axes) in Baka Pygmies for six demographic and transmission parameters (panels A–F).

<p>For each panel, adults are in green, youths in red, children in blue. The dashed vertical line shows the value of the parameter adopted in the base scenario; the two solid vertical lines delimit plausible ranges of variation in this population, where these can be estimated from the literature. The dotted black line illustrates the time in years required for the prevalence in adults to approach to within 1% of the equilibrium value.</p

Genetic diversity of hpAfrica1 and hpNEAfrica haplotypes isolated from Baka Pygmies and non-Baka agriculturalists.

<p><i>N</i>, total number of sequences; <i>h</i>, number of haplotypes; <i>S</i>, Number of polymorphic (segregating) sites; <i>k</i>, average number of nucleotide differences; <i>π</i>, nucleotide diversity; SD, standard deviation.</p

Model predicted prevalence under the base scenario versus observed <i>H. pylori</i> prevalences by age in Cameroon.

<p>The model-predicted prevalence rises in steps with the three age classes (i.e., child, youth, adult).</p