{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T21:20:58Z","timestamp":1790198458282,"version":"4.1.0"},"reference-count":30,"publisher":"American Society of Tropical Medicine and Hygiene","issue":"6","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2017,6,7]]},"abstract":"<jats:p>More than 2 billion people are infected with parasites globally, and the majority have coinfections. Intestinal protozoa and helminths induce polarizing CD4<jats:sup>+<\/jats:sup> T-helper cell 1 (Th1) mediated cytokine responses within the host. Such immune polarization may inhibit the ability of the host to mount an adequate immune response for pathogen clearance to concurrent pathogens. The current study evaluated the plasma cytokine profile in <jats:italic>Ascaris<\/jats:italic> and <jats:italic>Giardia<\/jats:italic> coinfected children compared with <jats:italic>Giardia<\/jats:italic>- and <jats:italic>Ascaris<\/jats:italic>-only infected children. Fecal samples and blood samples were collected from asymptomatic 3-year-old children living in the district of Quininde, Ecuador. Stool samples that tested positive for <jats:italic>Giardia lamblia<\/jats:italic>-only, <jats:italic>Ascaris lumbricoides-<\/jats:italic>only, or <jats:italic>G. lamblia<\/jats:italic> and <jats:italic>A. lumbricoides<\/jats:italic> coinfections were confirmed by quantitative real-time polymerase chain reaction. Plasma samples from the study subjects were used to quantitate cytokines. A total of 39 patients were evaluated. Children with coinfection had a significant decrease in Th1 cytokine production, interleukin 2 (IL-2) (<jats:italic>P<\/jats:italic> &lt; 0.05), IL-12 (<jats:italic>P<\/jats:italic> &lt; 0.05), and tumor necrosis factor alpha (<jats:italic>P<\/jats:italic> &lt; 0.05) compared with <jats:italic>Giardia<\/jats:italic>-only infected children. Coinfected children had an increase in IL-10\/interferon gamma (IFN-\u03b3) ratio compared with uninfected (<jats:italic>P<\/jats:italic> &lt; 0.05) and <jats:italic>Ascaris<\/jats:italic> alone (<jats:italic>P<\/jats:italic> &lt; 0.05). The increased IL-10\/IFN-\u03b3 ratio in the setting of decreased Th1 cytokine response indicates Th2 polarization in the coinfected group. Reduced Th1 cytokines in children coinfected with <jats:italic>Ascaris<\/jats:italic> and <jats:italic>Giardia<\/jats:italic> may impair the host's ability to eradicate <jats:italic>Giardia<\/jats:italic> infection leading to chronic giardiasis.<\/jats:p>","DOI":"10.4269\/ajtmh.16-0580","type":"journal-article","created":{"date-parts":[[2017,3,13]],"date-time":"2017-03-13T16:07:08Z","timestamp":1489421228000},"page":"1394-1399","source":"Crossref","is-referenced-by-count":23,"title":["Comparison of Cytokine Responses in Ecuadorian Children Infected with Giardia, Ascaris, or Both Parasites"],"prefix":"10.4269","volume":"96","author":[{"given":"Jill","family":"Weatherhead","sequence":"first","affiliation":[{"name":"National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea Ar\u00e9valo","family":"Cort\u00e9s","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlos","family":"Sandoval","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maritza","family":"Vaca","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Martha","family":"Chico","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sophia","family":"Loor","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philip J.","family":"Cooper","sequence":"additional","affiliation":[{"name":"Fundaci\u00f3n Ecuatoriana para la Investigaci\u00f3n en Salud, Quito, Ecuador."},{"name":"Facultad de Ciencias Medicas, de la Salud y la Vida, Universidad Internacional del Ecuador, Quito, Ecuador."},{"name":"Institute of Infection and Immunity, St. George's University of London, London, United Kingdom."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rojelio","family":"Mejia","sequence":"additional","affiliation":[{"name":"National School of Tropical Medicine, Baylor College of Medicine, Houston, Texas."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"2795","reference":[{"key":"ref1","series-title":"Int J Parasitol","first-page":"1171","article-title":"Polyparasitism and its impact on the immune system","volume":"40","author":"Supali","year":"2010"},{"key":"ref2","series-title":"Proc Biol Sci","first-page":"20131671","article-title":"Antagonism between two intestinal parasites in 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