1. OVERVIEW
As of 11th of September 2007, sixteen districts of Northern Iraq have reported laboratory-confirmed cases of cholera putting over 3 million people exposed to public health risk from this ongoing outbreak. Nine out of eleven districts of Sulaymaniyah province, all five districts of Kirkuk province and two out of seven districts of Erbil province are now affected by this cholera outbreak in Northern Iraq. This outbreak, first unfolded in Kirkuk province on 14 August spread to Sulaymaniyah province on 23 August and then to Erbil province on 6th of September caused 10 deaths so far and continues to be of major threat to public health in the region.
Specific control measures to contain this ongoing outbreak and limit its spread to other areas have been reinforced by the health authorities of the affected provinces with strong technical support from WHO.
From 23 August to 10 September 2007, the cumulative number of cases of acute watery diarrhoea reported from five out of eleven districts of Sulaymaniyah province stands at 6,142 including 9 deaths with an overall case fatality rate of 0.14%. Of these reported cases, Vibrio cholerae has been laboratory confirmed in 339 stool specimens.
While during the period from 29 July to 11 September 2007, the health authority of Kirkuk province reported a total of 6,368 cases of acute diarrhoeal disease including 1 death (CFR: 0.01%). The first index case of cholera, confirmed by laboratory test, was reported from Kirkuk province on 14 August 2007. So far, from the Kirkuk province, a total of 482 stool specimens were tested positive for Vibrio cholerae.
On 6th of September, the first laboratory-confirmed case of cholera was reported for the first time from one of the districts (Erbil centre) of Erbil province. Later on, laboratory confirmed cases were also reported from Koisnjaq district. So far, 23 stool specimens collected from these two districts of Erbil province have tested positive for Vibrio cholerae serogroup 01 Inaba. Although cumulative number of cases of acute watery diarrhea since the first index case of Vibrio cholerae was laboratory confirmed is still not available, the Communicable Disease Control unit of Erbil Directorate of Health reported 3,406 cases of diarrhoeal disease with no death from the entire province between 1st of September and 10th of September, 2007.
Table-1: Cases of AWD and diarrhoeal diseases reported from three provinces of Northern Iraq
|
Province
|
No of districts
affected |
Date outbreak
started |
No of AWD/DD
cases reported |
No of deaths
reported |
CFR (%)
|
| Sulaymaniyah |
5
|
23/08/07
|
6,142
|
9
|
0.14
|
| Kirkuk |
5
|
14/08/07
|
6,368
|
1
|
0.01
|
| Erbil |
2
|
06/09/07
|
3,406
|
Note: The time period of these reported cases varies from one province to another. For details please refer to the text above.
2. PATTERN OF TRANSMISSION IN SULAYMANIYAH PROVINCE
As of 10th of September, the outbreak, since unfolded in the province on 23 August, has spread to eight out of eleven districts in the province (Please see the map above) exposing over 1.3 million people living in this province to this epidemic risk. As accumulation of surveillance data from the field shows signs of improvement, the overall epidemiological pattern of the outbreak is gradually becoming more conspicuous.
The daily progression of cases, as plotted in figure-1, shows that barring some inadequacies and incompleteness in reporting during the earlier part of this outbreak in Sulaymaniyah province, the number of cases are now gradually increasing and possibly after 1st of September, the reported cases are appearing to come in a wave which seems to be more consistent with any outbreak. The apparent increase in number of reported cases in recent time compared to the immediate past may also be attributed to improvement in surveillance system in the province as the recent reports received from the field suggests that surveillance data are now being collected and assimilated from all the hospitals as well as from primary health centers in the province. The sudden drop in cases reported on 7th of September may be due to the weekly holiday (Friday) in the province wherein reports were, possibly, not received or available from all health centres.
Although the outbreak, as illustrated in figure-1, has not shown any definite peak, it is expected that with the improvement of surveillance system, already visible, the transmission pattern of this outbreak could be better explained in the coming weeks. Therefore, owing to lack of comprehensive surveillance data, the overall epidemiological trend of the prevailing situation needs to be interpreted with caution.
The majority of cases reported from Sulaymaniyah province belong to the over 5 year age group. Comparable data on distribution of reported cases by two broad age groups (Under 5 and over 5 year age group), available since 29th of August, reveals that between 29 August and 9 September 2007, a total of 4,289 cases of acute watery diarrhea were reported in the above 5 year age group from Sulaymaniyah province compared to only 599 cases reported during the same period in the below 5 year age group.