Epidemiological overview as of 25 Dec 2017
Between 8 Nov 2017 and 25 Dec 2017, 2440 suspected case-patients with diphtheria were reported in the settlements of forcibly displaced Myanmar nationals, Cox’s Bazar (Figure 1), 80 of which were reported on 25 Dec 2017 (Figure 2). Date of onset information is missing for 111 (4.5%) case-patients.
Estimated attack rates (expressed as number of cases per 10,000 population) are shown in Figure 3. These estimates are based on population figures from 07 December 2017. N.B. due to difficulties in locating reported residence, only 1509 out of 2440 (61.8%) total casepatients have been included in the attack rate calculations, which therefore likely under-estimate the true attack rates. Efforts are ongoing to map these case-patients.
The age distribution of suspect case-patients shows that, approximately: one-quarter are among the 0-5 year age group, one-third are in the 5-10 year age group, and one-fifth are aged between 10-15 years (Figure 4). Importantly, 25.3% of the suspected case-patients are aged 15 years and older.
1090 (44.7%) of the case-patients are male, while 1337 (54.8%) of the case-patients are female (Figure 5). Information on sex was missing for 12 (0.5%) of case-patients.
Signs and symptoms prevalence
There are 247 (10.1%) suspected case-patients without information on signs and symptoms. Of those suspected case-patients with this information, the prevalence of signs and symptoms is shown in Figure 6 (N.B. patients with no information are excluded from this analysis):
There are 26 deaths recorded in the linelist thus far.
The median [IQR] delay from symptom onset to presentation at health facilities was 2 [2 - 3] days. Among those who have died, the median [IQR] delay from symptom onset to death was 7 [4.25 - 10] days.
Contact tracing and follow-up for chemo-prophylaxis is an important component of the outbreak response strategy. Close contacts are defined as “those sleeping in the same shelter or who have been directly exposed to nasopharyngeal secretions of the patient on a prolonged or regular basis (example, school classmates other patients in wards and medical staff)”.
There is no information on number of close contacts for 518 (21.2%) suspected case-patients.
Among those case-patients for whom information is available on number of close contacts, the median [IQR] number of contacts is 5 [3 - 7], while the total range is 0-21 (Figure 7).