Outbreak Investigation of Chikungunia and other febrile Illnesses - - PowerPoint PPT Presentation

Outbreak Investigation of Chikungunia and other febrile Illnesses Al-Hawtah District, Lahj Governorate 21March – 8 May, 2012

Mohamed A. A. Saleh, MD, Epidemiologist 1st Cohort - FETP

Yemeni International Congress On Infectious Disease 16-18 December 2014 , Sana'a , Yemen

• Chikungunya virus(CHIKV)is an acute viral infection
• Transmitted to humans through bite of an infected

adult female Aedes mosquito

• It is one of the epidemic vector-borne diseases,

recently re-emerged in Asian and African

• First reported case in humans was in Tanzania in

1952

Background

• In Yemen, the CHIKV was first confirmed in Al-

Hodeida governorate in late 2010

• Dengue fever which has a clinical manifestation

similar to CHIKV is also reported from Yemen

• The disease in Yemen occurs yearly in the period

between October to April

Background

• Lahj governorate experienced a major dengue

fever outbreak, notably March and May 2010

• In 18 April 2012, first three cases of CHIKV

reported from Al-Hawtah district, Lahj governorate

• In 21 April 2012 another 20 cases were reported
• FETP residents asked to investigate the outbreak

Background

Objectives

• Confirm diagnosis of outbreaks
• Describe characteristic of cases
• Recommend control and prevention measures to

local health authorities and help implementation

Methods

• The investigation took place in Al-Hawtah

district between 21 April–8 May,2012

• Active house to house search
• Investigation form used to collect demographic

and clinical data of cases

• Line listing was developed
• 10 blood samples collected and sent to central

Methods (cont.)

Case Definition

• Suspected CHIKV Case

– Acute Febrile Illness and severe joint pain/joint swelling/joint stiffness/arthritis with one of the following sign/symptoms:

• Severe headache
• Retro-orbital pain, Muscle pain, Bone pain
• Rash

AND – No evidence of haemorrhagic manifestation – Normal PLT count ( > 100,000 cell/mL) – Malaria was negative

Methods (cont.)

Case Definition

• Probable CHIKV Case

– Met suspected case Chikungunya fever criteria AND one of the following

• epidemiological linkage with confirmed case
• Single positive CHIKV IgM
• Confirmed CHIKV Case

– Met suspected case Chikungunya fever criteria AND one of the following

• Identify CHIK virus by PCR and/or Viral isolation
• Two fold rising of CHIKV IgM from pair serum

Methods (cont.)

• Environmental Survey to look for breeding sites
• Entomological survey to identify the mosquito

and larvae

• Data collected was entered and analyzed using

Epi Info and excel

Results

• A total of 234 CHIK cases met the case definition
• The index case is a child of 14 year age with date
• f onset 21 March, 2012
• The attack rate was 7.5 per1000 population
• No deaths occurred among the suspected cases

Fig 1. Distribution of the cases by date of onset, Lahj, Yemen 2012

5 10 15 20 25

19-Mar 21-Mar 23-Mar 25-Mar 27-Mar 29-Mar 31-Mar 02-Apr 04-Apr 06-Apr 08-Apr 10-Apr 12-Apr 14-Apr 16-Apr 18-Apr 20-Apr 22-Apr 24-Apr 26-Apr 28-Apr 30-Apr 02-May 04-May 06-May 08-May 10-May 12-May

• No. of cases

days suspect confirmed

1st report Index case house to house and school health education indoor fogging

Fig 2. Clinical Manifestation of Chikungunya fever cases

0.4 56 64 95 100 100 20 40 60 80 100 bleeding rash joints swelling arthralgia headache fever

%

Table 1: Incidence rate of cases by gender and age group

Population No. cases Incidence per 1000 Gender M 15876 122 8 F 15253 112 7 Age group <10 7657 45 6 10-19 6947 44 6 20-29 6762 57 8 30-39 4235 32 8 40+ 5528 56 10 Total 31129 234 8

Fig 3: Location of Chikungunya outbreak in Lahj Governorate

Fig 4: Distribution of the cases by district

209 23 1 50 100 150 200 250 Al-Hawtah Tuban Almusamir

No Cases

District

52% 48% 46% 48% 50% 52% FISH MARKET OTHER ARIA

Al-Hawtah sub district

Laboratory Results

• Three cases were CHIKV IgM positive (ELISA)
• One case was dengue IgM positive

Environmental Survey

Main container type water reservoir in the household

Entomological Survey

• In 9 sites in Al Hawtah

district major containers examined for mosquito breeding site

• In all sites adult Aedes spp

mosquito and mosquito larva isolated

Entomological Results

Al-hawtah District Fish market

• No. House Exam.

332 121

House Positive

132 60

House Index (%)

40% 50%

Container Exam

1699 245

Container Positive

217 68

Container Index (%)

13% 28%

Breteau Index (%)

0.20 50%

Actions taken

• Integrated meeting with malaria, surveillance,

and education programs

• Met medical and paramedical staff (midwives)

in MCHC and Ibn Khaldon hospital

• Met district health office and education

directors in Al-Hawtah and Tuban districts

• Met the coordinators of the school health

program for health education of students

• In door fogy spray for an entire Al-Hawtah

District started

Meeting activities

Training Activities

Indoor fogy spray Activities

Conclusion

• Lahj outbreak is most probably due to CHIKV
• Importation of the CHIKV from another

governorate is likely e.g. fishermen from Hodeidah

• Control of the outbreaks was successful due to

utilizing an integrated response

Limitations

• No system for integrated planning and action between

different authorities

• Poor laboratory capacities in the country
• Limited CHIKV awareness among physicians and health

workers

• Presence of vector with no intervention measures
• Lack of guideline for Dengue/CHIKV outbreak

investigations

Recommendations

• Strengthen surveillance system throughout

training, guidelines, and financial support

• Ensure intersectional cooperation between

health and other stakeholder

• Provide training for health professionals on early

detection, reporting and treatment of cases

• Increase CHIKV community awareness

Recommendations

• Improve laboratory capacity for rapid outbreak

confirmation

• Decentralize rapid response and strategies for

emergency needs to governorate

• Support school health programs in students’

education for prevention of health problems

Thanks For Your Attention