Enhanced dengue sentinel surveillance in Sri Lanka
2015 (English)In: Tropical medicine & international health, ISSN 1360-2276, E-ISSN 1365-3156, Vol. 20, no Suppl. 1, 133-133 p.Article in journal, Meeting abstract (Other academic) Published
Introduction: Dengue poses a signiﬁcant socioeconomic and disease burden in Sri Lanka, where the geographic spread, incidence and severity of disease has been increasing since the ﬁrst dengue hemorrhagic fever (DHF) epidemic occurred in 1989. Periodic epidemics have become progressively larger, peaking in 2012 with 44 456 cases. Passive surveillance was established nationwide more than a decade ago but dengue notiﬁcations have been based on clinical diagnosis, with infrequent laboratory conﬁrmation. To obtain more accurate data on the disease burden, a laboratory-based enhanced sentinel surveillance system was established in Colombo Municipality, the area with the highest dengue incidence. Here we describe the study design and the results of the ﬁrst 2 years (2012–2014).
Methods: Three government hospitals and two outpatient clinics in Colombo District were selected for the sentinel surveillance. All patients presenting with undifferentiated fever were enrolled, if consent given, capped at a maximum of 60 patients per week. Acute blood samples were taken from all enrolled subjects and tested by dengue-speciﬁc PCR, and NS1, and IgM – ELISA at the time of ﬁrst presentation. A sub-set of 536 samples was sent to Duke-NUS Singapore for quality assurance, virus isolation and serotyping.
Results: Between 1 April, 2012 and 31 March, 2014, 3127 patients were enrolled, 964 (30.9%) as outpatients and 2160 (69.1%) as inpatients. The mean age was 22.3 years (SD = 17.5) and the time of ﬁrst presentation was at day 4 of illness. For inpatients, 1687 (78.1%) of all febrile cases had laboratory-conﬁrmed dengue. For outpatients, the proportion of conﬁrmed dengue was 237 (24.6%). The mean duration of hospitalization was 4.1 days (SD = 1.85). The proportion of DHF in lab-conﬁrmed hospitalized dengue cases was 22.1% and 4 patients (0.21%) died. Serotypes 1 and 4 were the only viruses detected in this sample (serotype 1: 85%; serotype 4: 15%). The clinicians’ diagnosis for dengue at time of ﬁrst presentation had a sensitivity of 92% and speciﬁcity of 23%.
Conclusions: Dengue infection was responsible for a high proportion of febrile illnesses during 2012–2014, with serotypes 1 and 4 circulating. A signiﬁcant proportion (22%) of hospitalized dengue cases developed DHF, but the case fatality rate was low. Clinicians’ judgment was associated with good sensitivity, but to enhance speciﬁcity it is important to add laboratory conﬁrmation of dengue.
Disclosure: This research was funded by the European Commission under the 7th Framework and conducted by DengueTools partners (www.denguetools.net).
Place, publisher, year, edition, pages
[Tissera, H.; Palihawadana, P.; Amarasinghe, A.; Muthukuda, C.; Botheju, C.] Minist Hlth, Epidemiol it, Colombo, Sri Lanka. [Tissera, H.] Natl Dengue Control Unit, Colombo, Sri Lanka. [Gunasena, S.] Med Res Inst, Colombo, Sri Lanka. [da Silva, D.] Genentech Res Inst, Colombo, Sri Lanka. [Sessions, O.] Nanyang Technol Univ, Duke NUS Grad Med Sch, Singapore 639798, Singapore. [Leong, W. -Y.; Wilder-Smith, A.] Nanyang Technol Univ, Lee Kong Chian Sch Med, Singapore 639798, ngapore. [Lohr, W.; Byass, P.; Wilder-Smith, A.] Umea Univ, Umea, Sweden. [Gubler, D.] Duke NUS Grad Med Sch, Colombo, Sri Lanka., 2015. Vol. 20, no Suppl. 1, 133-133 p.
Public Health, Global Health, Social Medicine and Epidemiology
IdentifiersURN: urn:nbn:se:umu:diva-109928ISI: 000360758800324OAI: oai:DiVA.org:umu-109928DiVA: diva2:861342
The 9th European Congress on Tropical Medicine and International Health (ECTMIH), Basel, Switzerland, September 6-10, 2015