Cholera in Zimbabwe: Epidemiological Bulletin Number 516-22 Nov 2008 2863 99 3.5 409 14 23-29 Nov 2008 3254 136 4.2 465 19 30 Nov 6 Dec 2008 4499 159 3.5 643 23 7-13 Dec 2008 2841

Source: Ministry of Health and Child Welfare Rapid Disease Notification System 1

Cholera in Zimbabwe: Epidemiological Bulletin Number 5

Week: 4 Jan 2009- 10 Jan 2009

Foreword This is the 5th epidemiological bulletin to be issued since the onset of a countrywide Zimbabwe cholera epidemic first reported in August, 2008. Bulletins are to be published weekly to coincide with the end of an epidemiological week (Sunday to Saturday). Daily cumulative caseload updates are posted on the OCHA website http://ochaonline.un.org/Default.aspx?alias=ochaonline.un.org/zimbabwe The bulletin provides a weekly overview of the epidemic in Zimbabwe, including province by province data, to inform and improve the continuing public health response. It also provides guidance to agencies on issues relating to data collection, analysis and interpretation, and suggests operational strategies on the basis of epidemiological patterns so far. The WHO Team welcomes feedback and data provided by individual agencies. Given the scope of this epidemic, errors and omissions are inevitable: we will be grateful for any information that helps to rectify these.

Please send any comments and feedback to the Cholera Control and Command Centre Email: [email protected].

Toll free number for alert by district and province is 08089001 or 08089002 or 08089000 Mobile number for alerts is 0912 104 257


Table of contents 1. Introduction 3

1.1. Map and population 3 1.2. Cholera treatment centres (CTC and CTU) 3

2. National Overview 4 2.1. Global picture 4 2.2. Case definition 5 2.3. Number cases and CFR 5 2.4. Attack rates and proportion of cases per district 7 2.5. Community deaths 9 2.6. Conclusion: hot spots for this week 10

3. Surveillance findings by province 10 3.1. Harare 10 3.2. Bulawayo 12 3.3. Mashonaland West 12 3.4. Mashonaland Central 12 3.5. Mashonaland East 13 3.6. Midlands 13 3.7. Masvingo 14 3.8. Manicaland 14 3.9. Matabeleland South 15 3.10. Matabeleland North 15

4. Discussion 16 4.1. Alerts and early warning system 16

5. Acknowledgements 16


1. Introduction 1.1. Map and population

1.2. Cholera treatment centres (CTC and CTU) There are 172 Cholera Treatment Centres (CTC/CTU) distributed over the country. 74 of the 172 CTC/CTU so 43% of them are run by the MoHCW. The others are receiving support from NGOs and partners. On average, one CTC/CTU is covering a population of 211 046 persons with a noted peak in Harare of 670 928 persons per CTC/CTU. Table 1. Number of CTC/CTU per province, as of Jan 10th, Zimbabwe

Province Population Number of CTC Average catchment population per CTC

Harare (Harare city+ Chitungwiza) 2,012,784 3 670928 Bulawayo 718,278 1 718278 Manicaland 1,665,451 36 46263 Mash Central 1,056,666 25 42267 Mash East 1,196,772 26 46030 Mash West 1,300,012 35 37143 Masvingo 1,401,672 31 45215 Mat North 748,317 0 - Mat South 693,230 7 99033 Midlands 1,554,058 8 194257 TOTAL 12347238 172 211046


Figure 2 (map): Location of the cholera treatment center (CTC and CTU) in Zimbabwe, as of 10 Jan 2009

Figure 3(map): Location of the 2 cholera treatment centers (CTC) among Harare city suburbs, as of 10 Jan 2009

2. National Overview 2.1. Global picture

New cholera cases and deaths continue to be reported. The cholera outbreak is not yet under control with nine of ten provinces reported cases for the epidemiologic week 04/1/08 - 10/1/09. To date and as of 10 January 2009, a cumulative total of 37 806 suspected cases and 1912 deaths have been reported to the World Health Organization (WHO), through the Ministry of Health and Child Welfare's (MoHCW) surveillance department. Number of cases have increased from last week as weel as the number of deaths. Case-fatality rates (CFR, the proportion of cases that die of the

Budiriro polyclinics

Beatrice hospital


disease) based on reported cases increased markedly this week to 6 % (5.9% exactly) similar to the week preceding the Christmas and New year’s holiday, and is still much higher than expected for a cholera outbreak (normally <1%). To date since November 16th 2008, 587 cases per day are reported and 31 persons are dying every day of cholera. This week (4 Jan -10 Jan 2009) nearly half of the deaths (41%) are occurring outside treatments centre suggesting continued problems associated with the unavailability of health care in the country. The highly affected provinces this week are:

1. Mashonaland West (increase cases and CFRs > 5% and high attack rates and 1/3 of the total weekly number of cases)

2. Midlands, (increase cases and CFRs > 5% and high attack rates) 3. Manicaland (CFRs > 5% and high attack rates) 4. Mathebeleland South (increase cases) 5. Chitungwiza (CFRs > 5%) 6. Masvingo (CFRs > 5%) 7. Mashonaland central (increase cases)

2.2. Case definition The cholera control guidelines for Zimbabwe state that the definition of suspected cholera cases is "in an area where there is a cholera epidemic, a patient aged 2 years or more develops acute watery diarrhoea, with or without vomiting". A confirmed cholera cases is “when Vibrio cholerae is isolated from any patient with diarrhoea”. This is adapted/modelled after the WHO case definition for cholera. Including all ages in the case definition somewhat reduces specificity (i.e. more non-cholera childhood diarrhoea cases are included), but essentially does not impede meaningful interpretation of trends. However, teams should monitor any shift in the age distribution of cases, which might indicate a changing proportion of non-cholera cases among patients seen. However, up to this point in the outbreak, we have been collecting data from all patients regardless of age. This is because we collect aggregate data every day which does not include ages. Data is also reported via line lists which do include ages. This information takes more time to come in, but in the future we aim at analysing data by age and separate out the <2 year olds at that point for official reporting. So while respecting the case definition for Zimbabwe, we continue to collect case data for all ages to avoid delay in responding to the current outbreak.

2.3. Number cases and CFR For the week 04/01/09 - 10/1/09, 4594 new cases of cholera were reported, an increase from the 3690 cases reported last week. New deaths from cholera reported this week were 272 (a threefold increase from the 79 of last week). Cases of cholera continue to be reported from 9 of 10 provinces (8 rural provinces and 2 urban provinces-Harare and Bulawayo), although outbreaks are localized by province and vary in their characteristics. Figure 1 demonstrates the cholera cases reported nationwide. This week data provide proof that week 28 Dec-3 Jan (Christmas and New year’s holidays period) was an artefact in the surveillance as this week 4 Jan-10 Jan the number of cases is back to around 6000 cases/week. Case-fatality rates (CFR, the proportion of cases that die of the disease) based on reported cases increased markedly this week to 6 % (5.9% exactly) similar to the week preceding the Christmas and New year’s holiday, and is still far above the <1% target. The CFR for the week 04/10/09 - 10/1/09 is 5.9%, compared to 2.1 % last week. Figure 1 demonstrates CFRs by week nationwide.


Figure 4 : New cholera cases, with case-fatality rates, by week. Zimbabwe, Nov 08 - Jan 09 * For week 7-13 December, gaps in reporting of data were noted. ** For week 28 December 08- 3 January 09, probable under reporting of number of cases and death during the Christmas- New Years holiday period

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The method of calculating CFR at this time and since the beginning of the epidemic is total deaths reported (institutional and community deaths) / total cases reported. This has the same meaning as “lethality”. CFRs vary by district and reflect issues of access to care, quality of care, and underlying prevalence of co-morbid conditions such as HIV/AIDS and malnutrition The number may not accurately reflect the quality of care once admitted to a treatment facility, as deaths in the community (not admitted) have been included in the calculation. But in some districts, they also report cases in the community in the total number of cases so the calculation of the institutional CFR and the comparison between institutional CFR and community CFR are not appropriate. Figure below shows the cumulative number of cholera cases, with the cumulative case-fatality rates since consistent data are collected. Figure 5: Cumulative cholera cases, with cumulative case-fatality rates. Zimbabwe, Nov 08 - Jan 09

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On average since November 16th 2008, 587 cases per day and 31 deaths per day are reported with a peak of 819 cases per day in 21-27 Dec 2008 and 52 per day in 14-20 Dec 2008. Table 6. Cases and deaths per day, from week 16/11/08 - 22/11/08 to week 04/01/09 - 10/01/09, Zimbabwe Week Cases Deaths CFR (%) Cases per day Deaths per day 16-22 Nov 2008 2863 99 3.5 409 14 23-29 Nov 2008 3254 136 4.2 465 19 30 Nov 6 Dec 2008 4499 159 3.5 643 23 7-13 Dec 2008 2841 257 9.0 406 37 14-20 Dec 2008 5379 367 6.8 768 52 21-27 Dec 2008 5730 358 6.2 819 51 28 Dec 08-3 Jan 09 3690 79 2.1 527 11 4-10 Jan 2009 4594 272 5.9 656 39 Total 587 31

Figure below shows the cumulative CFR by district since the onset of the epidemic. Most affected districts have high (>5%) overall rates of death among cholera cases (CFR). Districts with cumulative CFRs over 1% are noted in the majority of the provinces (8 of the 10 provinces). Only Matabeleland North and Bulawayo have no districts with a CFR over 5%, however Bulawayo have still a cumulative CFR > 1 %. Figure 7 (map): Cumulative case-fatality rates, by district. Zimbabwe, as of 10 Jan 2008

2.4. Attack rates and proportion of cases per district Attack rates (AR, total number of cases/population) are a measure of the incidence of infection. An AR of 0.6-1.0% is often seen in cholera endemic areas with poor sanitary conditions. The ARs shown here are subject to surveillance bias (higher in areas with better reporting), and are not specific for particular populations at higher risk. Variations in CFR would be expected to occur within districts. The AR is based on district population projections for 2008.

no cases/deaths01.1 - 5.0above 5


Table 8 . Cumulative attack rates, by district. Zimbabwe, as of 10 Jan 2009

The most affected provinces for this week in term of number of cases are from far Mashonaland West (AR= 120/100 000 inhabitants), then Mathebeleland South (AR= 63/100 000 inhabitants), Manicaland (AR= 47/100 000 inhabitants). Table 9. Attack rate (AR) per 100 000 inhabitants by provinces ,Zimbabwe, as of 10 Jan 2009

Provinces Population

Number cases week (4 Jan-10 Jan 09)

Cumulative number of cases (since beginning of data collection)

Weekly AR (per 100 000)

Cumulative AR (per 100 000

Harare (Harare city+ Chitungwiza) 2,012,784 501 11767 24.9 584.6 Bulawayo 718,278 8 383 1.1 53.3 Manicaland 1,665,451 783 4477 47.0 268.8 Mash Central 1,056,666 278 859 26.3 81.3 Mash East 1,196,772 401 3642 33.5 304.3 Mash West 1,300,012 1,565 9168 120.4 705.2 Masvingo 1,401,672 448 2565 32.0 183.0 Mat North 748,317 0 2 0.0 0.3 Mat South 693,230 438 4272 63.2 616.2 Midlands 1,554,058 172 671 11.1 43.2 TOTAL 12,347,240 4,594 37806 37.2 306.2

This week, Mashonaland West is representing 1/3 of the total weekly number of cases, followed by Manicaland (17.0%) and Harare (10.9%). Since the beginning of the outbreak, most of the cases are coming from Harare (31.1%), then Mashonaland West (24.3%).

Attack Rate (per 100,000)

00.1 - 99.9100.0 - 499.9500.0 - 999.91,000 and above


Table 10. Proportion of cases by provinces ,Zimbabwe, as of 10 Jan 2009

Provinces

Number cases week (4 Jan-10 Jan 09)

Cumulative number of cases

Proportion of cases (%) week (4 Jan-10 Jan 09)

Cumulative proportion of cases (%)

Harare (Harare city+ Chitungwiza) 501 11767 10.9 31.1 Bulawayo 8 383 0.2 1.0 Manicaland 783 4477 17.0 11.8 Mash Central 278 859 6.1 2.3 Mash East 401 3642 8.7 9.6 Mash West 1,565 9168 34.1 24.3 Masvingo 448 2565 9.8 6.8 Mat North 0 2 0.0 0.0 Mat South 438 4272 9.5 11.3 Midlands 172 671 3.7 1.8 TOTAL 4,594 37806 100.0 100.0

2.5. Community deaths Community deaths are defined here as deaths suspected from cholera which occur outside of health facilities. The number of community deaths can reflect how well the population is being covered by the CTC/CTU's. However, interpretation of this figure must be made with caution since verbal autopsies are not always done to confirm cause of death. Reports of community deaths are not available from all provinces and if available are reported sporadically. For the epidemiologic week 04/01/09 - 10/1/09 reports available are found in Table 1. The figures suggest that the continued problems are associated with the unavailability of health care, mainly because of human resources (nurses are paid as of today, one dollar a month). The proportion of deaths occurring outside treatment centres, per week, could in any site be used as a useful proxy indicator of coverage: the target should be 0%. This week, without taking into account Harare, where community deaths are irregularly (or even not) reported, more than 1/3 of the deaths (41%) are occurring outside treatments centre. In some districts (Mashonaland East) more deaths are recorded in the community than in the treatments centres. Table 11. Proportion of deaths that occur outside cholera treatment centres, week 04/01/08 - 10/01/09, selected* provinces *(as for Harare, deaths outside CTC, which are called community deaths, are irregularly/not reported)

Province Deaths within treatment centres

Deaths outside treatment centres

Proportion of deaths occuring outside treatment centres (%)

Bulawayo 0 0 0 Mashonaland West 117 67 36 Mashonaland Central 10 8 44 Mashonaland East 19 20 51 Manicaland 62 59 49 Masvingo 27 20 46 Matabeleland North 0 0 0 Matabeleland South 11 3 21 Midlands 16 11 41 Total 272 188 41


2.6. Conclusion: hot spots for this week

In particular, an increase in cases was noted in Mashonaland West, Mashonaland central, Midlands, Mathebeleland South. CFRs are > 5% in Chitungwiza, Mashonaland West, Midlands, Masvingo, Manicaland. The most affected provinces for this week in term of attack rates are from far Mashonaland West, then Mathebeleland South and Manicaland. This week, Mashonaland West is representing 1/3 of the total weekly number of cases, followed by Manicaland (17.0%) and Harare (10.9%).

3. Surveillance findings by province 3.1. Harare

Harare reported 501 cases this week, down from 689 cases reported last week. However, the number of deaths is stable (10 in comparison of 9 last week) but the CFR has increased from 1.3% last week to 2% this week. The global data for Harare will not presented globally using an epidemic curve from now on, as it doesn’t reflect adequately the epidemic situation for Harare. The data analysis for Harare is separated into Harare City and Chitungwiza, the Harare satellite town. We aimed in the future bulletins to separate Harare city in its different suburbs. 3.1.1. Chitungwiza Chitungwiza is the Harare satellite town located South West. In August 2008, an outbreak was reported in St Mary's and Zengeza sections of Chitungwiza (population 320 000), about 25 Km south of Harare city centre. Altogether 118 cases were treated, and the outbreak lasted 4 weeks. A second outbreak in Chitungwiza began in November and still continues even if the number of cases is decreasing. This week 82 cases and deaths (CFR= %) were reported, representing a stable number of reported cases and an increase in CFR compared to the previous week (80 cases and 5 deaths ,CFR=6.3%). Figure 12. New cholera cases with case-fatality rates, by week, Chitungwiza, 17 August 08- 10 Jan 09.

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3.1.2. Harare City In Harare City, 419 cases and 4 deaths (CFR=1%) were reported, representing an decrease in cases (from 609) and a stable CFR (from 0.9%) from the previous week. However community deaths have not been consistently reported or even not reported at all since the beginning of the outbreak and “plan A” cases were not included in Beatrix hospital, so data have to be analysed with caution. We aimed in the future bulletins to separate Harare city in its different suburbs. At the moment, there are 2 CTCs only in Harare (Budiriro polyclinics, Beatrice Infectious Diseases Hospital), which both of them are reporting. Figure 13 (maps) Distribution of cases in Harare city from 11 Oct 2008 to 22 Dec 2008

Figure 14. New cholera cases with case-fatality rates, by week, Harare city, 16 Nov 08- 3 Jan 09

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Institute Of Agricultural Engineering

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3.2. Bulawayo Bulawayo is the second major town in Zimbabwe after Harare. It needs to be noted that Bulawayo is one of the few towns/cities in Zimbabwe for whom ZINWA, the national water agency is not in charge of water supply. Bulawayo continues to report a low number of cases (8) from 8 last week. There were 0 deaths for the 3nd consecutive week. The situation seems under control in Bulawayo for 2 weeks now. Figure 15. New cholera cases with case-fatality rates, by week, Bulawayo, 16 Nov-10 Jan.

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3.3. Mashonaland West

This week 1565 cases were reported from Mashonaland West: a marked increase from the 379 reported last week. Deaths increased from 29 to 117. The weekly CFR is stable and higher than the 1% target : 7.7% this week (7.7% last week). Figure 16. New cholera cases with case-fatality rates, by week, Mashonaland West, 16 November- 3 Jan

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3.4. Mashonaland Central

Cholera cases reported from Mashonaland Central are increasing for 3 weeks now: an increase this week from 278 (127 reported last week). 10 deaths were reported only resulting in a decrease of the CFR 3.6% (in comparison of CFR=8.7% last week).


Figure 17. New cholera cases with case-fatality rates, by week, Mashonaland Central 16 Nov - 10 Jan.

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3.5. Mashonaland East

Mashonaland East reported 401 cases and 19 deaths a slight decrease from the 475 cases and 28 deaths reported last week. The CFR (CFR=4.7%), has decreased from 5.9% last week. Figure 18. New cholera cases with case-fatality rates, by week, Mashonaland East 16 Nov - 10 Jan.

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3.6. Midlands Midlands reported 172 cases and 16 deaths (CFR=9.3%), representing an threefold increase in the number of cases from last week (cases 53, deaths 7) The CFR decreased from 13.2% to 9.3 % this week but is still remains over 9 times as much as what is expected for a cholera outbreak.


Figure19. New cholera cases with case-fatality rates, by week, Midlands 16 Nov- 10 Jan.

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3.7. Masvingo

Cases reported from Masvingo has been stable for 3 weeks (448 this week in comparison with 456 last week). Deaths increased to 27 (the19 deaths last week). CFR increased too from 4.2% last week to 6% this week. Figure 20. New cholera cases with case-fatality rates, by week, Masvingo, 7 Nov- 10 Jan.

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3.8. Manicaland

New cases reported from Manicaland decreased by nearly 50 % this week, from 1375 last week to 783 cases, Number of deaths is stable in comparison of last week (62 this week from 58 last week), resulting in a doubling CFR of 7.9% (last week 4.2%).


Figure 21. New cholera cases with case-fatality rates, by week, Manicaland, 7 Nov- 10 Jan.

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3.9. Matabeleland South

Matabeleland South province includes Beitbridge, which is a bustling town on the border with South Africa. Many residents of Beitbridge are working in Musina in South Africa. For this reporting week Matabeleland South reported a tripling number of cases ( from 128 to 438 this week) but a decrease in the number of deaths (from 18 to 11 deaths this week), resulting in an important decrease of the CFR ( from 14.1% to 2.5% this week). Figure 22. New cholera cases with case-fatality rates, by week, Matabeleland South, 12 Nov- 10 Jan.

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3.10. Matabeleland North

No further cases or deaths were reported this week like the week before. Only 2 cases have been reported in week 21-27 Dec 08 for Matabeleland North.


4. Discussion

4.1. Alerts and early warning system

A simple early warning system continues in place using data reported daily by MoHCW officers from districts and provinces. A new criteria has been added this week “Districts with cases re-occurring after more than 14 days”. Four criteria for prioritizing high priority districts for investigation are currently as follows:

• Daily reported cases>30 • Daily CFR >5% • Daily number of deaths outside health facility/CTC/CTU of more than 3 • Districts with cases re-occurring after more than 14 days

Districts crossing any of the above thresholds are prioritized for response activities.

5. Acknowledgements We are very grateful to MoHCW District Medical Officer, Provincial surveillance officers, especially Provincial Medical Director and Environmental Heath Officer, and MoHCW's department of surveillance, who have helped to gather and transmit the bulk of the information presented here. Likewise, we acknowledge agencies, including members of the Health and WaSH clusters, who have kindly shared their data with our team. MoHCW has recognized and thanked the efforts made by NGOs assisting in the response and providing support to MoHCW to the cholera treatment centres (MoHCW – 16/12/2008). This document would not have been possible without the contributions of the WHO data management team, who are part of the C4 Cholera Command and Control Center.

Documents

Cholera in Zimbabwe: Epidemiological Bulletin Number 516-22 Nov 2008 2863 99 3.5 409 14 23-29 Nov 2008 3254 136 4.2 465 19 30 Nov 6 Dec 2008 4499 159 3.5 643 23 7-13 Dec 2008 2841