Epidemiologic
Characteristics of Recent Measles Outbreaks in ROK
Park Ok
Director, Division of VPD control and NIP,
KCDC
Immunization History for MMR Vaccine
• 1980 MMR was introduced
• 1983 MMR was included in NIP
• 1997 2 dose MMR was recommended by NIP
• 2000-2001 Nationwide huge measles outbreak
• 2001 MR Supplementary immunization activity
• 2002 Immunization registry
• 2005 Web based immunization registry
• Routine MMR vaccine schedule
- MMR 1 at 12-15mo, MMR 2 at 4-6 yr
* MMR Vaccine used in Korea
Reported Cases of Measles (2008-2014. Jul) in Korea
1 2
1 3 2 3 4 15 30
1
94
32
100
328
1
14
19
8
46
0 50 100 150 200 250 300 350 400 450
2008 2009 2010 2011 2012 2013 2014
Imported Import-linked Imported-virus Unknown Under investigation 43
• Measles incidence: 8.2 cases per 1M population
• Annual median number: 100.6 cases [range, 2-419 cases]
Cases
Year 17
114 107
419
0 10 20 30 40 50 60 70
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Under investigation Imported Import-linked Imported virus Unknown
n %
Under investigation 40 9.5
Imported 15 3.6
Import-linked 30 7.2 Imported virus 328 78.3
Unknown 6 1.4
Total 419 100.0
Measles Cases in Korea, by Import Status, Jan-July 2014
Epidemiological week Cases
Jul 18, 2014 2013 2012 2011 2010
Total 419 107 2 43 114
Imported 15 4 2 3 1
Import-associated 358 103 - 32 94
Endemic - - - - -
Unknown 46
(under investigation)
- - 8 19
Country Cases No. Details The
Philippines
6 Multicultural family
Korean returning from international travel Foreign worker
International student, Korean
2 2 1 1 China 5 Multicultural family
Korean returning from international travel International student, Korean
International student, Chinese International worker, Chinese
1 1 1 1 1 Vietnam 3 Multicultural family
Korean returning from international travel 2 1
Singapore 1 Foreign visitor 1
Details of Imported measles cases
0 50 100 150 200 250
B3 D8 H1 Unknown
Cases
Genotype
Genotype n
B3 209
D8 7
H1 5
Unknown* 198
Total 419
* Unknown: includes cases under investigation
Measles Cases in Korea, by Genotype, Jan-July 2014
WHO Measles-Rubella Bulletin, Vol 8 Issue 6 (June 2014)
0 10 20 30 40 50 60 70 80 90 100
0 1 2 3 4 5 6 7 8 9 1011121314151617181920212223242526272829303132333435363738394041424344454647
Age (yr) Cases
Measles Cases in Korea by Age, Jan-July 2014
0 20 40 60 80 100 120
Age Group
Cases
(no.) %
~1yr 100 23.9 unvaccinted 1-3yr 73 17.4 day care 4-6yr 6 1.4 kidergarten 7-12yr 15 3.6 elementary
schooler
13-15yr 14 3.3 middle schooler 16-18yr 69 16.5 high schooler 19-29yr 98 23.4 college
students 30yr~ 40 9.5
Measles Cases in Korea by Age Group, Jan-July 2014
Cases
Age (yr)
Age (yr) Vaccination History
Total 0 1 2 Unknown
0
99 . . . 991~3
44 25 . . 694~6
3 1 2 . 67~19
4 4 100 23 13120~
4 5 27 69 105Subtotal
156 36 129 90 4100 20 40 60 80 100 120 140
0 1~3 4~6 7~19 20~
0 1 2
Unknown
Age (yr) Cases
Vaccination History
Measles Cases in Korea,
by Age Group and Vaccination History, Jan-July 2014
38%
9%
31%
22% Never
1 dose
2 doses
Unknown
Region Confirmed New cases in recent 2 weeks
Imported cases
Genotype
B3 D8 H1
Total 419 6 15 209 7 5
Seoul 93 - 2 71 - -
Incheon 49 1 - 25 - -
North Gyeonggi 32 - 1 17 - -
South Gyeonggi 114 5 4 25 1 2
Gangwon 2 - 1 1 - -
Daejeon 17 - - 11 2 -
Chungbuk 8 - - 4 - -
Chungnam 12 - 2 6 4 -
Gwangju 2 - - 2 - -
Jeonbuk 4 - - 2 - -
Jeonnam 41 - - 27 - -
Daegu 11 - 1 2 - 3
Ulsan 3 - 1 3 - -
Gyeongbuk 16 - 1 6 - -
Busan 13 - 2 7 - -
Gyeongnam 1 - - - - -
Jeju 1 - - - - -
Measles Cases in Korea by Region, Jan-July 2014
* Unvaccinated cases were more likely to present classic manifestations of measles [OR=3.656 (p <0.000)](among 330 measles cases with available data).
Clinical Manifestations of Measles Cases in Korea, Jan-July 2014
Classic measles (F+R+3C)
Non-classic measles
Vaccinated 87 82 169
Unvaccinated 128 33 161
215 115 330
•Rash: mild, atypical
H-F-M dz?, acne?, varicella?
•Hospitalization rate: 34.8%
•Pneumonia, encephalitis, death
: not reported so far
0 10 20 30 40 50 60 70
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
가족 병원 어린이집 지역사회 학교 학원 회사
H중학교
K대학교
B중고교
B병원 D고교 대전,파주
Daejeon, Mokpo, Gyeonggi(Paju,Bundang,Bucheong) hospital
Epidemiological curve of Measles Cases in Korea
by Outbreaks, Jan-July 2014
Epidemiological week
Cases
Feb. Mar. Apr. May
A (48)
B (31)
?
C (38)
D (1)
G (19)
J (19) F
(2)
E (2)
H (6m) I (13m ) A Hospital
B Hospital
C Hospital
K (13)
12 persons (12~13)
D Mid. School
L (10m )
M (17 )
N (33 )
?
O (1 )
P (6m ) Family
Transmission Chain of Outbreaks in Mokpo and Jeonnam Province
Apr May Jun
17 18 19 20 21 22 23 24 25 26 27 28 29 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3 4 5 6 7
R/O Sepsis, R/O Meningitis
R/O Mycoplasma infection, R/O Viral infection Phillippines
(Cebu)
Deteted during Epi. investigation
Exposure Rash onset
Infective period
Nurse of the ward where E pt admitted A: 33
B: 32 C: 33 D: 27
E: 2M F: 30
Worked at emergency room when A pt visited
Hospital visit
Transmission Chain of Outbreaks in Health Care Workers of a Hospital
Feb. Mar. Apr.
K (13m)
B (22m)
G (11m)
F (25)
L (13m)
H (8m) A
(12)
C (9m)
D (18m)
E (11m)
F (9m)
May
G (11m)
H (12m)
I (12m) From Philippine
L (14m)
A Hospital
B Hospital
C Hospital
O (10m)
M (1)
N (10m)
P (1)
Transmission Chain of Outbreaks in North Gyeonggi Province
Outbreak Name Region Cases No. Import State Genotype Rash onset Duration Age range
S Hospital Daejeon 6 Imported virus B3 2.3 24 days 11M - 31
M Children’s hospital
N. Gyeonggi (Paju)
7 Imported
(Philippines)
B3 2.25 23 days 8M – 12
J Hospital S. Gyeonggi (Bundang)
5 Imported virus B3 2.27 55 days 10M – 1
M Children’s hospital
Jeonnam (Mokpo)
5 Imported virus B3 3.5 15 days 6M – 1
S ENT clinic Chungbuk 4 Unknown - 3.10 3 days 35 - 45
D Hospital N. Gyeonggi (Ilsan)
6 Imported
(Philippines)
B3 3.13 30 days 9M - 25
G Hospital Jeonnam (Mokpo)
6 Imported virus B3 3.19 33 days 1-47
S children’s hospital
S. Gyeonggi (Pucheon)
22 Imported virus B3 3.20 ongoing (7.13) 5M – 1
G Hospital Incheon 16 Imported virus B3 4.4 58 days 7M - 30
H Hospital Jeonnam (Mokpo)
5 Imported virus B3 5.1 45 days 14 - 33
S Hospital Gyeongnam (Andong)
13 Imported virus B3 5.1 ongoing (6.28) 5M - 35
S Hospital S. Gyeonggi (Pucheon)
23 Imported virus B3 5.12 22 days 2M - 47
B Hospital Busan 7 Imported
(Philippines) /Imported virus
B3 5.9 24 days 11M - 33
Measles Outbreaks in Health Care Setting, Korea, 2014
* Outbreak: cluster of more than two cases
# Outbreaks in Korea, Jan-July 2014 Total 21 measles outbreaks
Hospital(13), School(7), and Office(1) Average size: 12 cases [ranges, 3-85 cases]
Average duration: 31 days [ranges, 3-58 days]
Outbreak Name
Region Cases No. Import State
Genotype Setting Rash onset
Duration Age range
G Residence Academy
S. Gyeonggi (Kwangmyeog)
9 Imported
virus
B3 Boarding
school
2.27 58 days 18 - 20
H Middle school
Jeonnam (Mokpo)
15 Imported virus
B3 School 3.14 37 days 12 - 13
K Univ Seoul 85 Imported
virus
B3 University 4.8 51 days 18 - 44
G Company Chungnam 3 Imported D8 Office 4.21 30 days 26 – 38
B Upper school
Seoul 17 Imported
virus
B3 School 5.13 23 days 13 - 17
Y High school Seoul 4 Imported
virus
B3 School 5.18 6 days 15 - 17
S High school Daegu 3 Imported
(China)
H1 School 5.23 26 days 17 - 18
D High school Daegu 4 Imported
(China)
H1 School 6.16 Ongoing (7.4) 17 - 18
Measles Outbreaks in other than Health Care Setting,
in Korea, Jan-July 2014
* Outbreak: cluster of more than two cases
1 1 5
19
43
11
3 3
0 5 10 15 20 25 30 35 40 45 50
3.23-29 3.30-4.5 4.6-4.12 4.13-19 4.20-26 4.27-5.3 5.4-10 5.11-17 5.18-24 5.25-31 6.1-6.7 6.8-6.14 6.15-6.16
Cases
Week
Catch-up(5.15-17)
An Outbreak in K University and Catch Up Campaign
• There are bimodal peaks; aged <1 year and aged 17-20 years.
• The main outbreak settings were hospitals and schools.
• Significant proportion of measles cases in Korea, Jan-July 2014 was vaccinee (40.0%).
• Among 419 confirmed measles cases, there were 15 (3.6%) imported cases; 14 (93.9%) occurred in Korean residents
returning from international travel, and 1 (6.1%) occurred in foreign visitor.
• Measles importation were associated with travel from 4 countries: the Philippines, China, Vietnam, and Singapore.
• Outbreak-related cases comprised 265 (63.2%) of total measles cases.
• Predominant measles genotype was B3.
Summary of Surveillance Data of Measles Cases in Korea,
Jan-July 2014
Continuous import from abroad
Hospital infections among infants
Outbreaks in previously vaccinated youth
• Overseas travels during vacations (students for language course in abroad, international students from abroad, multicultural families)
• Diagnosis failure due to atypical symptoms at the first visit to clinics
• Delayed notice of outbreaks after transmissions of several generations through hospitals, families, and schools
• Imports from abroad hospital infection through contacts to imported cases transmission among family members and in community
transmission through infections at schools
Characteristics of the Recent Measles Outbreaks in Korea
WHO Measles-Rubella Bulletin, Vol 8 Issue 6 (June 2014)
Huge Outbreaks in Neighbor Countries
Huge outbreaks in neighbor countries
transmission by travellers
Continuous Imports from Abroad
Transmission routes
of measles cases in 2013 Total
Hospital Day care Family School Overseas travel
Community
61 2 13 14 4 13 107
(57.0%)
Transmission routes
of measles cases in 2014 as of Jul 18 Total
Hospital Day care Family School Overseas travel
Community
157 3 12 124 14 19 419
(37.5%)
2ndary Transmission in Children’s Hospital
7% of neonates have no measles Ab, 90% of infants have no measles Ab at 6 months of age in USA
J Infect Dis 2004;190:83, J Infect Dis 2007;196:1459
Measles Sero-positive Rates under 2 years olds in Korea
Measles Sero-positive Rates In infants under 1 year old
Kim KH, 2009
Kim SS et al. Vaccine23(2004)290–297
Decrease of Passive Immunity in infants
Atypical rash of a recent measles case
*Atypical mild measles clinical
features & low measles incidence Difficulty in diagnosis
홍역 발생 상황 평가 : 청소년/성인 백신 접종자 중심 집단적인 홍역발생
Typical measles rash
* Unvaccinated cases were more likely to present classic manifestations of measles
[OR=3.656 (p <0.000)](among 330 measles cases with available data).
Classic measles (F+R+3C)
Non-classic measles
Vaccinated
87 82
169Unvaccinated
128 33
161215 115 330
Atypical Measles Manifestations in Pts with Vaccination history
Index case
Early detection and notification from clinics are important for control
Delayed Notice Lead Wide Transmission
Index case
Early detection and notification from clinics are important for control
Delayed Notice Lead Wide Transmission
38%
9%
31%
22% Never
1 dose 2 doses Unknown
* A study in USA (2014.1.1-5.23)(n: 288)
: unvaccinated : 200(69%), unknown : 58(20%), vaccinated : 30(10%)
* A study in Japan (2014.1.1-3.13)(n: 183)
: unknown or unvaccinated : 146(80%), vaccinated : 37(20%)
Reported measles cases, Jan-July 2014, KCDC