Detecting extra-ocular Chlamydia trachomatis in a trachoma-endemic community in Ethiopia: Identifying potential routes of transmission

• Published in: PLoS neglected tropical diseases Vol. 14; no. 3; p. e0008120
• Main Authors: Last, Anna, Versteeg, Bart, Shafi Abdurahman, Oumer, Robinson, Ailie, Dumessa, Gebeyehu, Abraham Aga, Muluadam, Shumi Bejiga, Gemechu, Negussu, Nebiyu, Greenland, Katie, Czerniewska, Alexandra, Thomson, Nicholas, Cairncross, Sandy, Sarah, Virginia, Macleod, David, Solomon, Anthony W, Logan, James, Burton, Matthew J
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 01.03.2020; Public Library of Science (PLoS)
• Subjects: Adolescent; Adult; Animals; Biology and Life Sciences; Child; Child, Preschool; Chlamydia; Chlamydia infections; Chlamydia Infections - diagnosis; Chlamydia Infections - transmission; Chlamydia trachomatis; Chlamydia trachomatis - genetics; Chlamydia trachomatis - isolation & purification; Community-Acquired Infections - diagnosis; Community-Acquired Infections - transmission; Containers; Cross-Sectional Studies; Deoxyribonucleic acid; Diagnosis; Diptera - microbiology; Disease control; Disease transmission; Disease Transmission, Infectious; Distribution; DNA; Ethiopia; Feces - microbiology; Female; Flies; Fomites - microbiology; Funding; Hand - microbiology; Households; Humans; Identification and classification; Infant; Infections; Inflammation; Laboratories; Male; Medicine; Medicine and Health Sciences; Methods; Middle Aged; Nucleotide sequence; PCR; People and Places; Population; Real-Time Polymerase Chain Reaction; Research and Analysis Methods; Sexually transmitted diseases; STD; Studies; Surfaces; Surveying; Trachoma; Transmission; Tropical diseases; Young Adult; Ethiopia; United Kingdom > UK; Addis Ababa Ethiopia
• ISSN: 1935-2735; 1935-2727; 1935-2735
• DOI: 10.1371/journal.pntd.0008120

Trachoma elimination efforts are hampered by limited understanding of Chlamydia trachomatis (Ct) transmission routes. Here we aimed to detect Ct DNA at non-ocular sites and on eye-seeking flies. A population-based household survey was conducted in Oromia Region, Ethiopia. Ocular and non-ocular (faces, hands, clothing, water containers and sleeping surfaces) swabs were collected from all individuals. Flies were caught from faces of children. Flies, ocular swabs and non-ocular swabs were tested for Ct by quantitative PCR. In total, 1220 individuals in 247 households were assessed. Active trachoma (trachomatous inflammation-follicular) and ocular Ct were detected in 10% and 2% of all-ages, and 21% and 3% of 1-9-year-olds, respectively. Ct was detected in 12% (95% CI:8-15%) of tested non-ocular swabs from ocular-positive households, but in none of the non-ocular swabs from ocular-negative households. Ct was detected on 24% (95% CI:18-32%) of flies from ocular-positive households and 3% (95% CI:1-6%) of flies from ocular-negative households. Ct DNA was detected on hands, faces and clothing of individuals living in ocular-positive households suggesting that this might be a route of transmission within Ct infected households. In addition, we detected Ct on flies from ocular-positive households and occasionally in ocular-negative households suggesting that flies might be a vector for transmission within and between Ct infected and uninfected households. These potential transmission routes may need to be simultaneously addressed to suppress transmission.