Epidemiological Bulletin Number 46

Transcription

1 Foreword Epidemiological Bulletin Number 46 Week 6 (week ending 14 February 2010) This bulletin provides a weekly overview of the outbreaks and other important public health events occurring in Zimbabwe. It includes disaggregated data to inform and improve the continuing public health response by the various partners. 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 bulletin is published weekly. Note that the epidemiological week runs from Monday to Sunday. This edition covers week 6 (week ending 14 February 2010). The C4 team welcomes feedback. Data provided by individual agencies is welcome but will be verified with MOHCW structures before publication. Please send any comments and feedback to the Cholera Control and Command Centre Cholera_Taskforce@zw.afro.who.int. Toll free number for alert by district and province is or or Mobile number for alerts is Acknowledgements We are very grateful to MoHCW District Medical Officers, District and Provincial Surveillance Officers, Provincial Medical Directors, Environmental Heath Officers, and MoHCW's National Health Information Unit, who have helped to gather and share 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 recognizes and thanks the efforts made by NGOs and other partners assisting in the response and providing support to MoHCW. Highlights of the week: Cholera spreads in Masvingo Province No new reported cases of Pandemic Influenza A H1N1(2009) More Measles Cases reported in particular from Harare City Source: Ministry of Health and Child Welfare Rapid Disease Notification System 1

2 Figures See also summary tables (annex 1), maps (annex 2) and graphs (annex 3). The case definitions can be found in appendix 1 and detailed data by district are shown in appendix 2 Cholera 7 out of the 62 districts in the country have been affected by the cholera outbreak that started on 4 February,2010 compared to 54 districts last year at the same time. 57 cumulative cholera cases, 8 of which were confirmed and 1 death were reported by 14 February 2010 to the World Health Organization (WHO) through the Ministry of Health and Child Welfare's (MoHCW) National Health Information Unit. The crude case fatality rate since the outbreak started stands at 1.7%. In comparison by week 6, 2009, cumulative cases and deaths had been reported, with a crude case fatality rate of 4.8%. This year s case fatality rate is lower than last year s by 3.1%. Week 6 (8 14 February 2010) 42 suspected cases and 4 confirmed cases of cholera were reported this week. 32 suspected cases were reported from Masvingo Province districts namely; ward 27 and ward 28 Chivi 3, ward 30,Masvingo 2, Mwenezi 1 and ward 16, Chiredzi 26 and one death from Chiredzi. 10 cases were reported from Beitbridge. Investigation of a rumour of 7 cases of cholera from Zvishavane found that there was no cholera in the area. Geographical distribution of cases The cases reported so far came from the following districts: Beitbridge, Chivi, Chiredzi, Harare, Masvingo, Mwenezi and Shamva. Urban/Rural distribution of cases All of the cases currently reported are from rural areas. In comparison, during the corresponding week in 2009, 42 % cases came from urban areas whilst 58 % were from rural areas Assessments & response Chivi A CTC was set up at Nyahombe Clinic to ensure appropriate infection control and case management. Participatory Health Hygiene Promotion and NFIs were distributed to directly affected households and their neighbours. Residual spraying with HTH at the affected households was also done. Soap and ORS sachets have been provided to the clinic. 2 wells with hand pumps located 1, 300m from Nyahombe Clinic and one in the school 800m from clinic were rehabilitated by ACF. Diesel was given to ZINWA to enable it to pump water to the clinic. Chlorine was provided to the clinic and the clinic s tanks were repaired. NFI Distribution (Aquatabs, Soap, Buckets with taps) for a total of 2100 households has been planned and will be carried out in the next few days. Source: Ministry of Health and Child Welfare Rapid Disease Notification System 2

3 The water sources available are dominantly turbid surface water. There are very few protected water points (functional or non-functional). Chiredzi Chiredzi District Health Authorities coordinated response by the following partners: Merlin, ACF and Oxfam. Merlin dispatched an emergency response team (vehicle, nurse, EHO) to support emergency health response. They have taken the following items: ORP kits, Cholera beds, IEC materials, Ringers, IV giving sets and cannulae. Merlin has provided 25 litres of fuel to EHT based in Chiredzi for community surveillance. Communities are using river water for drinking. Oxfam has set up Oral Rehydration Point (ORP) in ward 16, Chiredzi District. Pandemic Influenza A H1N1 (2009) By week ending 31 January, 253 cumulative probable 1 cases of Pandemic H1N1 (2009) had been reported in Zimbabwe, 41 of which were confirmed by PCR (Polymerase chain reaction) to be Pandemic H1N1 (2009). Week 6 (8 14 February 2010) Zero cases of probable Pandemic Influenza A H1N1 (2009) were reported this week. As a result we are now in the eleventh week without a case reported. Geographical distribution of cases The following provinces have reported cases: Manicaland, Harare, Mashonaland East and Midlands. The affected 8 districts are: Harare Urban, Chivhu, Marondera, Goromonzi, Seke, Mutasa, Nyanga and Chirumhanzu. Assessments & response No samples were sent to the National Virology Laboratory this week. Measles Nearly 1350 suspected cases were reported since the start of the outbreak in September blood specimens have been received by the polio-measles laboratory and 248 cases have been confirmed to be Measles IgM positive. 23 of the total positive cases had dates of last vaccination. The vaccination status of the remaining 225 cases was not indicated. 65 community deaths have been reported. 43(17%) of the positive igm cases were in the below 9 months, 26 (11%) in the 9 12 months agegroup, 46 (19%) were in the 1-5 years agegroup, 104 (42.1 %) were in the 5-14 years agegroup and 28(11%) in the above 14 Years. Hence 205 (83%) of the positive cases were above the routine immunisation age ( 9 months -12 months) 1 See definition of probable case in Appendix 1 Source: Ministry of Health and Child Welfare Rapid Disease Notification System 3

4 The district measles IgM positive attack rates ranged from 0.4 to 17 per and the attack rate for all the affected districts is 3 per The lowest attack rate was for Masvingo and the highest was for Bubi. See table 4 for detailed distribution of the cases by age group and district and attack rates. Week 6 (8-14 February 2010) 14 specimens out of 134 received were IgM positive. 6 were negative, 1 indeterminate, 54 were not done and 59 had results pending. Hence the weekly positivity rate is 67%(14/21). The positive cases came from : Bindura 2, Goromonzi 1, Harare 6, Marondera 1, Murehwa 1, Mutoko 1, Seke 1 and Zvimba 1. See table 5 for detailed distribution. Geographical distribution of cases Since September 2009, 32 districts out of 62, have had at least 1 laboratory confirmed measles case namely: Bindura, Bikita, Bubi, Buhera, Bulawayo, Centenary, Chegutu, Chirumhanzu, Chipinge, Gokwe South, Goromonzi, Gutu, Harare (including Chitungwiza),Hwange, Hwedza, Insiza, Kwekwe, Makoni, Makonde, Marondera, Masvingo, Mt. Darwin, Mutare, Nyanga, Umzingwane, Seke, Zaka, Zvimba and Zvishavane. Confirmed laboratory Outbreaks 21 Districts had confirmed laboratory outbreaks. The Districts are shaded in table 3. Suspected Outbreaks 30 districts had suspected outbreaks. Assessments & response A National Measles Outbreak Coordination Committee was formed and is mainly constituted of MOHCW, WHO and UNICEF. More other EPI stakeholder will co-opted with time. It met and reviewed the evolution of the current measles outbreak and made plans on doing a risk analysis on districts that have not yet reported measles outbreaks this year as well as establishing the status of the national outbreak. The taskforce will meet again on 22 February It is expected to adopt effective control measures that are evidence based. Surveillance continued throughout the country. Buhera District All children aged 6 months to 14 years are being vaccinated with financial support from UNICEF,MSF and technical support from WHO and the Ministry in 9 wards. At time of reporting, over children had been vaccinated.a total of 30 nurses with 5 vehicles are vaccinating in the district. Report from the province indicates that considerable resistance is being experienced among the Johane Marange amongst who the outbreak is more pronounced. Source: Ministry of Health and Child Welfare Rapid Disease Notification System 4

5 Seke District(Epworth) Vaccinations conducted between Friday 12 th to Sunday 14th of February A total of 439 children were vaccinated (Age group targeted was 6 months to 14 years). A significant number of children was found to be overdue for most antigens in Epworth. Nyanga District District awaiting delivery of vaccine from national level to mount a response. WHO has provided some fuel for delivery of vaccine to the district Children 6 months to 14 years will be targeted. Anthrax Since the beginning of the year 13 cases of Anthrax were reported and a rumour of 1 case in Seke. The cases distribution is as follows: Kadoma 3, Shurugwi 8 and Chikomba 1 and Mwenezi 2. Week 6 (8 14 February 2010) No cases were reported. Assessments & response Vaccination of cattle was undertaken in Seke and Mhondoro Districts. Source: Ministry of Health and Child Welfare Rapid Disease Notification System 5

6 Annex 1: Summary Tables Table 1: Cumulative Cholera cases and deaths reported by district for the period week 6, 2010 District Cases Reported this week Confirmed Cases reported this week Cumulative Suspected Cases Cumulative Confirmed Cases Cumulative deaths Attack rate per Harare Shamva Mwenezi Beitbridge Chivi Masvingo Chiredzi Total Table 2: Age and Sex Distribution of Cumulative Confirmed H1N1 Cases from July 2009 to 31 January 2010 Under 5 Years 5-14 Years Years 30 Years and over District Male Female Male Female Male Female Male Female Chikomba Harare Mutasa Seke Unspecified District Total Table 3: Distribution of Measles IgM Positive by Age group and District since September 2009 District < 9 months 9 months -12 months 1-5 years 5-14 years >14 years TOTAL Attack rate per BIKITA BINDURA BUBI BUHERA BULAWAYO CENTENARY CHEGUTU CHIPINGE CHIREDZI Source: Ministry of Health and Child Welfare Rapid Disease Notification System 6

7 District < 9 months 9 months -12 months 1-5 years 5-14 years >14 years TOTAL Attack rate per CHITUNGWIZA GOKWE GOROMONZI GUTU HARARE HWANGE HWEDZA INSIZA KADOMA KWEKWE MAKONDE MAKONI MARONDERA MASVINGO MT DARWIN MUREHWA MUTARE NYANGA SEKE UMZINGWANE ZAKA ZVIMBA ZVISHAVANE TOTAL Table 4: Distribution of Confirmed measles cases by age group by district reported in week 6, 1-7 February District < 9 months 1-5 years 5-14 years >14 years TOTAL BINDURA GOROMONZI HARARE MARONDERA MUREHWA Source: Ministry of Health and Child Welfare Rapid Disease Notification System 7

8 MUTOKO SEKE ZVIMBA TOTAL Table 5: Some Key Measles Indicators as of 31 January 2010 Indicator Value Suspected Cases Blood Specimens received by Laboratory 812 Confirmed Cases 248 Deaths 50 Districts Affected 32 Overall Attack Rate 3/ Cases with Vaccination status 23/248 Source: Ministry of Health and Child Welfare Rapid Disease Notification System 8

9 Annex 2: Maps Map 1: Comparison of cumulative cholera cases by district as of week 6, 2009 and Source: Ministry of Health and Child Welfare Rapid Disease Notification System 9

10 Map 2: Cumulative probable Influenza A H1N1(2009) cases by district, July, February 2010 Source: Ministry of Health and Child Welfare Rapid Disease Notification System 10

11 Map 3: Comparison of Cumulative Measles IgM positive cases and Suspected Measles case by district reported this year, as at 7 February, 2010 Confirmed Cases Suspected Measles Cases Source: Ministry of Health and Child Welfare Rapid Disease Notification System 11

12 Annex 3: Graphs Graph 1:Ranking of District Cumulative Cholera Cases Reported as at week 6, 2010 Chiredzi Beitbridge Chivi District Mwenezi Masvingo Shamva Harare Urban Cholera Cases Graph 2: Logarithmof Cumulative Cholera Cases by week for the years 2009 and Log of Cholera Cases w28 w27 w26 w25 w24 w23 w22 w21 w20 w19 w18 w17 w16 w15 w14 w13 w12 w11 w10 w9 w8 w7 w6 w5 w4 w3 w2 w1 w53 w52 w51 w50 w49 w48 w47 w46 w45 w44 w43 w42 w41 w40 w39 w38 w37 w36 w35 w34 Epi Week Number Source: Ministry of Health and Child Welfare Rapid Disease Notification System 12

13 Graph 3:Ranking of District Probable H1N1 Cases Reported by July 2009 to 7 February 2010 Graph 3:Ranking of Confirmed Measles Igm Cases by District Reported from September 2009 to 14 February 2010 District HARARE BULAWAYO ZVISHAVANE GOKWE MAKONI BUBI MARONDERA NYANGA CHIPINGE CHEGUTU MUTARE MT DARWIN ZVIMBA SEKE CHITUNGWIZA BUHERA BINDURA BIKITA KWEKWE HWEDZA GUTU INSIZA GOROMONZI ZAKA UMZINGWANE MUREHWA MASVINGO MAKONDE KADOMA HWANGE CHIREDZI CENTENARY Measles IgM Cases Source: Ministry of Health and Child Welfare Rapid Disease Notification System 13

14 Graph 4:Ranking of Suspected Measles Cases by District Reported from September 2009 to 7 February 2010 District Harare Makoni Buhera Mutare Marondera Gokwe Kwekwe Nyanga Zvishavane Bikita Bulawayo Chegutu Seke Goromonzi Bubi Beitbridge Zvimba Hwedza Chitungwiza Mt Darwin Makonde Gwanda Chipinge Mudzi Binga Bindura Mutasa Insiza Gweru Centenary Shurugwi Gutu Umzingwane Mazowe Kadoma UMP Tsholotsho Mutoko Murehwa Masvingo Hwange Hurungwe Chivi Chinhoyi Bulilima Zaka Nkayi Lupane Kariba Chiredzi Chimanimani Suspect Measles Cases Graph 5:Distribution of Suspected Measles Cases by Week September 2009 to 14 February Suspect Measles Cases Week Number Source: Ministry of Health and Child Welfare Rapid Disease Notification System 14

15 Appendix 1: Case Definitions Cholera The Zimbabwe cholera state definition states that "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 case is when Vibrio cholerae is isolated from any patient with diarrhoea. This is adapted from the WHO case definition for cholera. The inclusion of all ages in the case definition somewhat reduces specificity, that is, inclusion of more non-cholera childhood diarrhoea cases. It, however, does not impede meaningful interpretation of trends. Teams should monitor any shift in the age distribution of cases, which might indicate a changing proportion of non-cholera cases among patients seen. Influenza A H1N1 Influenza A and B are two of the three types of influenza viruses associated with annual outbreaks and epidemics of influenza. Only influenza A virus can cause pandemics. The Zimbabwe IDSR technical guidelines define influenza case by a new sub type (including Avian flu Influenza A H5N1 and Swine flu Influenza A H1N1) as; Any person presenting with unexplained acute lower respiratory illness with fever (>38 ºC ) and cough, shortness of breath or difficulty breathing AND notion of exposures in the 7 days prior to symptom onset. Probable case definition: Any person meeting the criteria for a suspected case AND positive laboratory confirmation of an influenza A infection but insufficient laboratory evidence for H1N1 infection. Confirmed H1N1 case: A person meeting the criteria for a suspected or probable case AND a positive result conducted in a national, regional or international influenza laboratory whose H1N1 test results are accepted by WHO as confirmatory. There may be difficulty in telling apart mild cases of pandemic influenza from the seasonal influenza. Suspected measles: Any person with fever and maculopapular rash and cough OR Coryza (running nose) OR conjunctivitis (Red eyes) OR clinician suspects measles. Measles Outbreak Definition: A suspected outbreak is where you have a cluster of at least 5 suspected measles cases in a facility or district within a month whilst a confirmed outbreak is where you have a cluster of at least 3 confirmed measles IgM positive cases. Lab confirmed: Suspected case of measles with positive serum IgM antibody, with no history of measles vaccination in the past 4 weeks. Confirmed by epidemiologic linkage: Suspected case of measles not investigated serologically but has possibility of contact with a laboratory-confirmed case whose rash onset was within the preceding 30 days (same / adjacent districts with plausible transmission) Source: Ministry of Health and Child Welfare Rapid Disease Notification System 15