Refugee Settlements and Cholera Risks in Uganda, 2016–2019

Abstract

During 2016 to 2019, cholera outbreaks were reported commonly to the Ministry of Health from refugee settlements. To further understand the risks cholera posed to refugees, a review of surveillance data on cholera in Uganda for the period 2016–2019 was carried out. During this 4-year period, there were seven such outbreaks with 1,495 cases and 30 deaths in five refugee settlements and one refugee reception center. Most deaths occurred early in the outbreak, often in the settlements or before arrival at a treatment center rather than after arrival at a treatment center. During the different years, these outbreaks occurred during different times of the year but simultaneously in settlements that were geographically separated and affected all ages and genders. Some outbreaks spread to the local populations within Uganda. Cholera control prevention measures are currently being implemented; however, additional measures are needed to reduce the risk of cholera among refugees including oral cholera vaccination and a water, sanitation and hygiene package during the refugee registration process. A standardized protocol is needed to quickly conduct case–control studies to generate information to guide future cholera outbreak prevention in refugees and the host population.

Optimizing one-dose and two-dose cholera vaccine allocation in outbreak settings: A modeling study

“…Delay times range widely—the time from the first laboratory confirmation of cholera (or occurrence of humanitarian emergency) to the receipt of the official OCV request spans between 12 and 206 days [ 3 ]. These delays in vaccine shipment may result in campaigns starting after the outbreak is over [ 43 ]. Further, our results are in line with previous modeling that explored the optimal use of vaccine when multiple doses are required for other pathogens, finding that fractional strategies are optimal when the protection afforded by a lower-than-recommended dose is sufficiently high [ 37 , 44 – 46 ].…”

Contrasting Epidemiology of Cholera in Bangladesh and Africa

“…While vaccination of hotspot areas remains a key strategy, its use should also focus on routes of transmission, as suggested for Uganda [ 57 ] and Burundi [ 46 ], which focus on persons, including refugees, arriving from neighboring countries where cholera is common. Specific interventions for migrants must, however, be cognizant of the need to avoid stigma, yet still be effective.…”

An Age-stratified, Randomized Immunogenicity Trial of Killed Oral Cholera Vaccine with Delayed Second Dose in Cameroon

“…All analyses were done between DIGs for overall and for each age group considering DIG1 as the reference group. Baseline characteristics and study outcomes were compared using χ 2 test or Fisher exact test as appropriate for qualitative variables and Student’s t test for quantitative variables. Because of the imbalance of baseline titers, especially the higher baseline titers for DIG3, we calculated the geometric mean titer fold increase ratio by comparing the geomeans of the fold increase between baseline and follow-up sera.…”

“…This contributes to higher case fatality ratios early in outbreaks or in areas without access to treatment. 2 , 3 Furthermore, health systems of most vulnerable areas are characterized by limited access to water, sanitation, and hygiene (WASH), insufficient preparedness of health facilities and weakness of the epidemiological surveillance system. 4 Cholera vaccination, using the killed oral cholera vaccine (OCV) can reduce risk of cholera in areas that are prone to outbreaks.…”