| Autor: |
Watson CH; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom., Baker S; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Oxford University, Oxford, United Kingdom., Lau CL; Department of Global Health, Research School of Population Health, Australian National University, Canberra, Australia., Rawalai K; Project Heaven, Suva, Fiji., Taufa M; Fiji Centre for Communicable Disease Control, Ministry of Health and Medical Services, Suva, Fiji., Coriakula J; Pacific Research Center for the Prevention of Obesity and Non-Communicable Diseases, Fiji National University, Suva, Fiji., Thieu NTV; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam., Van TT; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam., Ngoc DTT; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam., Hens N; Center for Statistics, I-Biostat, UHasselt, Hasselt, Belgium.; Centre for Health Economic Research and Modelling Infectious Diseases, Vaccine and Infectious Disease Institute, University of Antwerp, Antwerp, Belgium., Lowry JH; School of Geography, Earth Science and Environment, University of the South Pacific, Suva, Fiji., de Alwis R; The Hospital for Tropical Diseases, Wellcome Trust Major Overseas Programme, Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam.; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, Oxford University, Oxford, United Kingdom.; Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom., Cano J; Department of Disease Control, London School of Hygiene & Tropical Medicine, London, United Kingdom., Jenkins K; Fiji Health Sector Support Programme, Suva, Fiji.; Telethon Kids Institute, Perth, Western Australia, Australia., Mulholland EK; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom.; Infection and Immunity, Murdoch Childrens Research Institute, Melbourne, Australia., Nilles EJ; Emerging Disease Surveillance and Response, World Health Organization Western Pacific Region, Suva, Fiji., Kama M; Fiji Centre for Communicable Disease Control, Ministry of Health and Medical Services, Suva, Fiji., Edmunds WJ; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom. |
| Abstrakt: |
Fiji, an upper-middle income state in the Pacific Ocean, has experienced an increase in confirmed case notifications of enteric fever caused by Salmonella enterica serovar Typhi (S. Typhi). To characterize the epidemiology of typhoid exposure, we conducted a cross-sectional sero-epidemiological survey measuring IgG against the Vi antigen of S. Typhi to estimate the effect of age, ethnicity, and other variables on seroprevalence. Epidemiologically relevant cut-off titres were established using a mixed model analysis of data from recovering culture-confirmed typhoid cases. We enrolled and assayed plasma of 1787 participants for anti-Vi IgG; 1,531 of these were resident in mainland areas that had not been previously vaccinated against S. Typhi (seropositivity 32.3% (95%CI 28.2 to 36.3%)), 256 were resident on Taveuni island, which had been previously vaccinated (seropositivity 71.5% (95%CI 62.1 to 80.9%)). The seroprevalence on the Fijian mainland is one to two orders of magnitude higher than expected from confirmed case surveillance incidence, suggesting substantial subclinical or otherwise unreported typhoid. We found no significant differences in seropositivity prevalences by ethnicity, which is in contrast to disease surveillance data in which the indigenous iTaukei Fijian population are disproportionately affected. Using multivariable logistic regression, seropositivity was associated with increased age (odds ratio 1.3 (95% CI 1.2 to 1.4) per 10 years), the presence of a pit latrine (OR 1.6, 95%CI 1.1 to 2.3) as opposed to a septic tank or piped sewer, and residence in settlements rather than residential housing or villages (OR 1.6, 95% CI 1.0 to 2.7). Increasing seropositivity with age is suggestive of low-level endemic transmission in Fiji. Improved sanitation where pit latrines are used and addressing potential transmission routes in settlements may reduce exposure to S. Typhi. Widespread unreported infection suggests there may be a role for typhoid vaccination in Fiji, in addition to public health management of cases and outbreaks. |
