Cholera outbreak caused by drinking unprotected well water contaminated with faeces from an open storm water drainage: Kampala City, Uganda, January 2019 (original) (raw)
Related papers
2020
Background: Kampala city slums, with one million dwellers living in poor sanitary conditions, frequently experience cholera outbreaks. On 6 January 2019, Lubaga Division notified the Uganda Ministry of Health of a suspected cholera outbreak in Sembule village. We investigated to identify the source and mode of transmission, and recommend evidence-based interventions.Methods: We defined a suspected case as onset of profuse, painless, acute watery diarrhoea in a Kampala City resident (≥2 years) from 28 December 2018 to 11 February 2019. A confirmed case was a suspected case with Vibrio cholerae identified from the patient’s stool specimen by culture or Polymerase Chain Reaction (PCR). We found cases by record review and active community case-finding. We conducted a case-control study in Sembule village, the epi-center of this outbreak, to compare exposures between confirmed case-persons and asymptomatic controls, individually matched by age group. We overlaid rainfall data with the ep...
On 20 June 2015, a cholera outbreak affecting more than 30 people was reported in a fishing village, Katwe, in Kasese District, southwestern Uganda. We investigated this outbreak to identify the mode of transmission and to recommend control measures. We defined a suspected case as onset of acute watery diarrhoea between 1 June and 15 July 2015 in a resident of Katwe village; a confirmed case was a suspected case with Vibrio cholerae cultured from stool. For case finding, we reviewed medical records and actively searched for cases in the community. In a case-control investigation we compared exposure histories of 32 suspected case-persons and 128 age-matched controls. We also conducted an environmental assessment on how the exposures had occurred. We found 61 suspected cases (attack rate = 4.9/1000) during this outbreak, of which eight were confirmed. The primary case-person had onset on 16 June; afterwards cases sharply increased, peaked on 19 June, and rapidly declined afterwards. After 22 June, eight scattered cases occurred. The case-control investigation showed that 97% (31/32) of cases and 62% (79/128) of controls usually collected water from inside a water-collection site " X " (OR M-H = 16; 95% CI = 2.4–107). The primary case-person who developed symptoms while fishing, reportedly came ashore in the early morning hours on 17 June, and defecated " near " water-collection site X. We concluded that this cholera outbreak was caused by drinking lake water collected from inside the lake-shore water-collection site X. At our recommendations, the village administration provided water chlorination tablets to the villagers, issued water boiling advisory to the villagers, rigorously disinfected all patients' faeces and, three weeks later, fixed the tap-water system.
Journal of Public Health in Africa
Introduction: On 10thFebruary 2017, Uganda Ministry of Health was notified of a suspected cholera outbreak in Nebbi district. The district experienced numerous cholera outbreaks with the latest in 2016. We investigated to determine the scope, mode of transmission, and exposures. Methods: We defined a suspected case as sudden onset of acute watery diarrhoea in a resident (>5 years) from Parombo or Panyimur subcounties in Nebbi district, during 1 January-9 March 2017. A confirmed case was a suspected case with culture-confirmed Vibrio cholerae from stool. We conducted descriptive epidemiology of case-persons to inform hypothesis generation and a case-control study involving 67 case-persons and 134 control-persons to test the hypothesis. Results: We identified 222 suspected case-persons; samples from two yielded Vibrio cholerae O139. Three case-persons died (CFR=1.4%). The epidemic curve indicated a point-source outbreak. Among 67 cases, 40 (60%) drank river water, compared with 56 ...
2020
Background: On 23 February 2018, the Uganda Ministry of Health (MOH) declared a cholera outbreak affecting more than 60 persons in Kyangwali Refugee Settlement, Hoima District, bordering the Democratic Republic of Congo (DRC). We investigated to determine the outbreak scope and risk factors for transmission, and recommend evidence-based control measures.Methods: We defined a suspected case as sudden onset of watery diarrhoea in a person aged ≥2 years in Hoima District, 1 February-9 May 2018. A confirmed case was a suspected case with V. cholerae cultured from a stool sample. We found cases by active community search and record reviews at Cholera Treatment Centres. We calculated case-fatality rates (CFR) and attack rates (AR) by sub-county and nationality. In a case-control study, we compared exposure factors among case- and control-households. We conducted an environmental assessment in the refugee settlement, including testing of water samples from stream water, tank water, and spr...
Background: On 12 October 2015, a cholera outbreak involving 65 cases and two deaths was reported in a fishing village in Hoima District, Western Uganda. Despite initial response by the local health department, the outbreak persisted. We conducted an investigation to identify the source and mode of transmission, and recommend evidence-led interventions to control and prevent cholera outbreaks in this area. Methods: We defined a suspected case as the onset of acute watery diarrhoea from 1 October to 2 November 2015 in a resident of Kaiso Village. A confirmed case was a suspected case who had Vibrio cholerae isolated from stool. We found cases by record review and active community case finding. We performed descriptive epidemiologic analysis for hypothesis generation. In an unmatched case-control study, we compared exposure histories of 61 cases and 126 controls randomly selected among asymptomatic village residents. We also conducted an environmental assessment and obtained meteorological data from a weather station. Results: We identified 122 suspected cases, of which six were culture-confirmed, 47 were confirmed positive with a rapid diagnostic test and two died. The two deceased cases had onset of the disease on 2 October and 10 October, respectively. Heavy rainfall occurred on 7–11 October; a point-source outbreak occurred on 12–15 October, followed by continuous community transmission for two weeks. Village residents usually collected drinking water from three lakeshore points – A, B and C: 9.8% (6/61) of case-persons and 31% (39/126) of control-persons were found to usually use point A, 21% (13/61) of case-persons and 37% (46/126) of control-persons were found to usually use point B (OR = 1.8, 95% CI: 0.64–5.3), and 69% (42/61) of case-persons and 33% (41/126) of control-persons were found to usually use point C (OR = 6.7; 95% CI: 2.5–17) for water collection. All case-persons (61/61) and 93% (117/126) of control-persons reportedly never treated/boiled drinking water (OR = ∞, 95% CI Fisher : 1.0 – ∞). The village's piped water system had been vandalised and open defecation was common due to a lack of latrines. The lake water was found to be contiminated due to a gully channel that washed the faeces into the lake at point C.