http://dspace.lamu.edu.zm:8080/handle/123456789/121 2026-10-13T05:26:45Z http://dspace.lamu.edu.zm:8080/handle/123456789/2908 Title: Incidence of Severe and Non severe Pertussis Among HIV-Exposed and -Unexposed Zambian Infants Through 14 Weeks of Age: Results From the Southern Africa Mother Infant Pertussis Study (SAMIPS), a Longitudinal Birth Cohort Study Authors: Gill, J. Christopher; Mwananyanda, Lawrence; Kwenda, Geoffrey; Magdalene, Mwale; Williams, L. Anna; Siazeele, Kazunga; Zhaoyan, Yang; Mwansa, James; Thea, M. Donald Abstract: Background. Maternal vaccination with tetanus, reduced-dose diphtheria, and acellular pertussis vaccine (Tdap) could be an effective way of mitigating the high residual burden of infant morbidity and mortality caused by Bordetella pertussis. To better inform such interventions, we conducted a burden-of-disease study to determine the incidence of severe and nonsevere pertussis among a population of Zambian infants. Methods. Mother–infant pairs were enrolled at 1 week of life, and then seen at 2- to 3-week intervals through 14 weeks of age. At each visit, nasopharyngeal (NP) swabs were obtained from both, and symptoms were catalogued. Using polymerase chain reaction (PCR) to identify cases, and a severity scoring system to triage these into severe/nonsevere, we calculated disease incidence using person-time at risk as the denominator. Results. From a population of 1981 infants, we identified 10 with clinical pertussis, for an overall incidence of 2.4 cases (95% confidence interval [CI], 1.2–4.2) per 1000 infant-months and a cumulative incidence of 5.2 cases (95% CI, 2.6–9.0) per 1000 infants. Nine of 10 cases occurred within a 3-month window (May–July 2015), with highest incidence between birth and 6 weeks of age (3.5 cases per 1000 infant-months), concentrated among infants prior to vaccination or among those who had only received 1 dose of Diphtheria Tetanus whole cell Pertussis (DTwP). Maternal human immunodeficiency virus (HIV) modestly increased the risk of infant pertussis (risk ratio, 1.8 [95% CI, .5–6.9]). Only 1 of 10 infant cases qualified as having severe pertussis. The rest presented with the mild and nonspecific symptoms of cough, coryza, and/or tachypnea. Notably, cough durations were long, exceeding 30 days in several cases, with PCRs repeatedly positive over time. Conclusions. Pertussis is circulating freely among this population of Zambian infants but rarely presents with the classical symptoms of paroxysmal cough, whooping, apnea, and cyanosis. Maternal HIV appears to increase the risk, while lack of effective exposure to DTwP increased the risk. Description: This article can also be accessed on DOI: 10.1093/cid/ciw526 2016-01-01T00:00:00Z http://dspace.lamu.edu.zm:8080/handle/123456789/2905 Title: Detection of Pneumococcal DNA in Blood by Polymerase Chain Reaction for Diagnosing Pneumococcal Pneumonia in Young Children From Low- and Middle-Income Countries Authors: Morpeth, C. Susan; Knoll, Maria Deloria; Scott, G. Anthony J.; Park, E. Daniel; Watson, L. Nora; Bagget, C. Henry; Brooks, W. Abdullah; Feikin, R. Daniel; Hammitt, L. Laura; Howie, R. C. Stephen; Kotlof, L. Karen; Levine, S. Orin; Madhi, A. Shabir; O'Brien, L. Kathrine; Thea, M. Donald; Adrian, V. Peter; Ahmed, Dilruba; Antonio, Martin; Bunthi, Charatdao; Deluca, N. Andrea; Driscoll, J. Amanda; Githua, Louis Peter; Higdon, M. Melisa; Kahn, Geof; Karani, Angela; Karron, A. Ruth; Kwenda, Geoffrey; Makprasert, Sirrirat; Mazumder, Razib; Moore, P. David; Mwansa, James; Nyongesa, Sammy; Prosperi, Christine; Sow, O. Sambao; Tamboura, Boubou; Whistler, Toni; Zeger, L. Scott; Murdoch, R. David Abstract: We investigated the performance of polymerase chain reaction (PCR) on blood in the diagnosis of pneumococcal pneumonia among children from 7 low- and middle-income countries. Methods. We tested blood by PCR for the pneumococcal autolysin gene in children aged 1–59 months in the Pneumonia Etiology Research for Child Health (PERCH) study. Children had World Health Organization–defined severe or very severe pneumonia or were age-frequency–matched community controls. Additionally, we tested blood from general pediatric admissions in Kilifi, Kenya, a PERCH site. The proportion PCR-positive was compared among cases with microbiologically confirmed pneumococcal pneumonia (MCPP), cases without a confirmed bacterial infection (nonconfirmed), cases confirmed for nonpneumococcal bacteria, and controls. Results. In PERCH, 7.3% (n = 291/3995) of cases and 5.5% (n = 273/4987) of controls were blood pneumococcal PCR-positive (P <.001), compared with 64.3% (n = 36/56) of MCPP cases and 6.3% (n = 243/3832) of nonconfirmed cases (P < .001). Blood pneumococcal PCR positivity was higher in children from the 5 African countries (5.5%–11.5% among cases and 5.3%–10.2% among controls) than from the 2 Asian countries (1.3% and 1.0% among cases and 0.8% and 0.8% among controls). Among Kilifi general pediatric admissions, 3.9% (n = 274/6968) were PCR-positive, including 61.7% (n = 37/60) of those with positive blood cultures for pneumococcus. Discussion. The utility of pneumococcal PCR on blood for diagnosing childhood pneumococcal pneumonia in the 7 low- and middle-income countries studied is limited by poor specificity and by poor sensitivity among MCPP cases. Description: Can also be accessed https://doi.org/10.1093/cid/cix145 2017-06-15T00:00:00Z