Cholera Sitrep_30

WHO report 4467 laboratory-confirmed cases of cholera This represents an increase of 111 laboratory confirmed cases of cholera since the last situation report on this cholera outbreak from the WHO (Sitrep 29).

As of 28 October 2007 (week 43), 28 districts of Northern Iraq and 16 districts in the south and centre have reported laboratory-confirmed cases of cholera.  The following are the affected governorates/districts that are affected by this cholera outbreak.:

North Irak:

• 13 out of the 14 districts of Sulaimaniyah governorate
• All five districts of Kirkuk governorate
• 6 out of the seven districts of Arbil governorate
• 4 districts in Dahuk (an increase of 3.)

Central and Southern Irak:

• 3 districts in Salah ad Din (Tikrit)
• 3 districts in Ninawa (Mosul)
• 3 districts in Diyala.
• 3 districts in Baghdad (an increase of 2)
• 2 districts in Basra
• 1 district in Wassit,
• 1 district in Anbar .

99% of Iraq’s cholera cases were reported from Kirkuk, Sulaymaniyah and Arbil, northern Iraq. Sporadic cases with definite history of travel and food consumption in Kirkuk were reported from Tikrit in Salah ad Din governorate; however, isolated cases with no epidemiological link to northern Iraq were also confirmed in Mosul, Wassit, Baghdad, Anbar and Basrah.

One of the important features in this outbreak is that most of the cases seen have mild to moderate signs and symptoms. The traditional signs and symptoms of severe dehydrating diarrhoea were seen only very occasionally, out of the 4,467 laboratory-confirmed cholera cases; 22 deaths were reported, most of the deceased had other, serious underlying morbidity.

Specific control measures to contain this ongoing outbreak and limit its spread to other areas have been reinforced by the concerned governmental departments of the affected provinces, with technical support from WHO.

In non-epidemic governorates, during the period 14 August – 28 October 2007, 36 cholera cases were discovered. Apart from affected governorates in Northern Iraq, there is no sign that cholera has spread to any other part of Irak. However, as the weather cools and become more favourable for transmission, the organism is expected to spread to other provinces.

New Laboratory-Confirmed Cholera Cases Reported During 15-21 October 2007 (Week 42):

• Kirkuk: 94 (of 697 samples tested)
• Sulaymaniyah: 49 (of 519 samples tested), 3 deaths.
• Erbil: 33 (of 713 samples tested)

Table 1: Laboratory confirmed cholera Cases, Irak, 14/08-28/10/2007

* Increase of 3 affected districts since this morning’s posting.

** Increase of 2 affected districts since this morning’s posting.

Pattern Of Transmission In Kirkuk Governorate:

• 69% of the total confirmed cholera cases reported from Irak, are from Kirkuk governorate.
• 90% of Kirkuk governorate cases are from the city.
• During 22-28 October 2007 (week 43), 1,300 new diarrhoea cases were reported, 827 (64%) in children under 5- vs. 473 (36%) in 5 years and older.
• 28 were confirmed cholera-positive among 479 samples tested.
• Figure 1  below shows an 6-fold increases in the number of diarrhoea cases among adults between week 34 and week 40, ending 7 October 2007, followed by a sharp decrease in reported diarrhoea cases in week 41.
• It should be noted that some of this decrease in diarrhoea during the last 4 days of week 42 especially among adults can safely be attributed to Eid holidays and population movement from urban to rural areas. 

  Fig. 1. Cases of diarrhoea vs. laboratory-confirmed cholera, by international week, Kirkuk, 20/8-28/10/2007
  

• Not all of the decrease is attributable to the movement between urban and rural areas during the last 4 days of Eid. During the same period there was a noticeable improved in quality and quantity of water supply.
• The figure shows that laboratory-confirmed cholera cases peaked at the level of 722 and 742 during weeks 38 (ending 23 September) and 39 (ending 30 September).
• This was followed by a sharp decrease during weeks 40 and 41 in the number of confirmed cholera cases.
• As noted in the last situation reports it is not known whether this is a real decrease in cholera cases or an apparent decrease due to the new strategy of collecting stools from only 10% of cases rather than 100% of cases in order to decrease the load on the laboratory and reduce the probability of contamination.
• As was also noted in the last situation reports this new policy seems to have been implemented without a similar change in the case definition of confirmed cholera to include all watery diarrhoea cases.
• It must be emphasised again that that the last 4 days of week 41 coincided with the Eid holidays, which might be another important reason for the sharp decrease in cases during this week.

Monitoring laboratory-confirmed cases

Monitoring the laboratory-confirmed cases there is:

1. A remarkable decrease in positives in Azadi lab during weeks 38-41.
2. A slow decline in Kirkuk PHL, Pediatric hospital, and total governorate positives.
3. An increase in positives of samples taken at Kirkuk Hospital lab.

   The authorities in Kirkuk have made the following observations:

4. In Kirkuk city, the highest attack rate was in Arafa while the contamination in the area was the lowest.
   At the same time, the lowest attack rate in Kirkuk city, was in areas with highest degree of contamination.
5. Therefore in Kirkuk city other reasons for spread of cholera apart from water contamination need to be considered.
6. In Dibbis District and at Taza PHCCC, there is correlation between cholera cases and water contamination, attributed to low chlorine level in the water projects, as well as the condition of pipe and storage of drinking water reservoirs.

Pattern Of Transmission In Sulaymaniyah Governorate:

Figure 2 below shows the hospital admissions for diarrhoea in the 2 main hospitals in Sulaymaniyah city vs. laboratory-confirmed cholera, Sulaymaniyah province, (27/08/07-28/10/07):

• During 22-28 October 2007 (week 43), there 49 were confirmed cholera-positive and 3 deaths (14 total since begin of the outbreak)
  Fig. 2 Diarrhea admissions in 2 hospitals Vs. total confirmed cholera in the province
  

    

• The total number of confirmed cholera cases is 1,227 (figure 2).
• At the beginning of the out break 90% of cases were reported from Sulaymaniyah city, however more cases were gradually been reported from outside the city indicating either spread of the disease to other districts outside Sulaymaniyah city or improved reporting from rural areas as well as relative good control inside the city.
• Fig 3 below shows the changing proportion of Cholera cases, Sulaymaniyah city Vs. areas outside side the city by week of onset, 26 Aug. to 28 Oct.

   

• Figure 4 below shows admitted diarrhoea cases to paediatric and teaching hospitals in Sulaymaniyah during the period 01/09 to 28/10/2007.
• It is clear that there was sustained increase between 2 and 6 October, followed by a sharp downward trend in the number of admitted patients.

   

Pattern Of Transmission In Arbil Province

During 22-28 October 2007 (week 43), 33 were confirmed cholera-positive; the total number of confirmed cholera cases in 6 affected districts is 211 (figure 5). Unlike the situation in both Kirkuk and Sulaymaniyah, the data of reported cases show a definitive downward trend in reported diarrhoea cases. The number of cases in week 38 (-23 September) and 39 (-30 September) is almost the same as the pre-outbreak figure. The very high number of cases in week 36 (-9 September) is most likely due to the feeling of panic following the declaration by MoH of the occurrence of cholera in Kirkuk and Sulaymaniyah. This success in Arbil is mainly due to the fact that key departments (water and sanitation) have recognized their important and vital role in the fight against cholera, unlike the situation in Kirkuk where key departments are just watching with minimal contribution.

• Figure 5 below shows the number of laboratory-confirmed vibrio cholerae cases, by date of onset, during 1 September – 28 October 2007. The number of confirmed cases peaked in weeks 38 and 39 and the plateaued at the level of 27-33 cases per week during the last 4 weeks.

  Fig. 5. Total diarrhoea, laboratory confirmed cholera, Arbil Governorate, by international week

  

Arbil seems to have a fairly sensitive diarrhoea disease surveillance system that was able to pick up cholera cases very early and swiftly responded and seems to have succeeded in halting and limiting the spread and magnitude of the outbreak.

Tags: Cholera Situation Reports, Water Borne Disease, World Health Organisation, الكوليرا