Twoyear Results From Hospitalbased Sentinel Surveillance Of Rotavirus Diarrhea In Children Less Than

1
Two-year Results From Hospital-based Sentinel
Surveillance Of Rotavirus Diarrhea In Children
Less Than 5 Years Old, Thailand, 2001 - 2003

• Rotavirus Surveillance Project
• Thailand

2
Collaborations

• Ministry of Public Health
• Bureau of Epidemiology
• National institute of Health
• Bureau of Communicable Diseases Control
• Nongkhai Hospital
• Chanthaburi Hospital
• Maesod Hospital
• Ramathibodi Hospital
• Hadyai Hospital
• Sakaeo Hospital
• Huay-kra-jao district health office,
  Chaokhunpaiboon Hospital, Kanchanaburi province

• International Organization
• CDC - USA
• Bill and Melinda Gates Childrens Vaccine Program
  at PATH

3
Background

• Although morbidity and mortality from diarrhea
  have decreased worldwide, the burden of severe
  disease remains high
• In 2002, 1,055,393 cases of diarrhea were
  reported in Thailand. Of these cases, one-third
  were children less than 5 years of age and 12
  required hospitalization
• Progress in the development of vaccines against
  rotavirus encouraged us to examine the rotavirus
  disease burden in Thai children and to assess the
  need for such vaccines
• When planning for rotavirus vaccine
  implementation, information is needed on the
  magnitude and trend of rotavirus infection and
  the serotypes circulating

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Specific Objectives

• To determine incidence of rotavirus in under 5
  population
• To monitor change of rotavirus serotype in the
  surveillance population
• To develop a hospital-based surveillance system
  for rotavirus diarrhea in Thailand

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Methods for hospital - based surveillance

• Population
• All children lt 5 years of age admitted to
  participating hospital with acute diarrhea or
  gastroenteritis and duration of diarrhea illness
  lt 7 days.
• Collect information
• Characteristics, clinical manifestations,
  treatment
• Collect stool to exam the causative agents
• Rotavirus and bacteria
• Laboratory tests for rotavirus
• polyacrylamide gel electrophoresis (PAGE) for
  rotavirus and PCR technique for serotype

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Surveillance sites and surveillance period
Nongkhai
Maesod
Nongkhai
Sakaeo
Measod
Ramathibodi
Chanthaburi
Sakaeo
Ramathibodi
Chanthaburi
Hadyai
Hadyai
Feb44 Jun44 Dec44 Jun45 Dec45 Jun46
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Two-year results

• Duration July 2001 June 2003 24 months
• Acute diarrhea or gastroenteritis 4,057 cases
• Rotavirus identification 838 cases
• (43.0 of available specimens)
• Rotavirus male female ratio 1.4 1

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Number of cases and specimens
Number of eligible patient 4,057cases
Collect specimens 2,202 (54.3)
No specimens 1,855 (45.7)
Identified agents 1,127 (51.2)
Negative 1,069 (48.5)
unavailable 6 (0.3)
Rotavirus 713 / 1,127 (63.3) Bacteria 289 /
1,127 (25.6) Both 125 / 1,127 (11.1)
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Proportion of case enrollment by month
Percentage
Total enrollment (2,333) 57.5
2001
2002
2003
10
Proportion of Rotavirus identification by month
percentage
Total average rotavirus (838) 43.0 of available
specimens
2001
2002
2003
Exclude inadequate samples for rotavirus test
252 samples
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Number of specimens and proportion of rotavirus
identification by month
Chanthaburi
Hadyai
Sakaeo
Nongkhai
Maesod
Ramathibodi?
Cases
2001
2003
2002
12
Proportion of rotavirus identification by site
Percentage
Chanthaburi
Hadyai
Sakaeo
Nongkhai
Maesod
Ramathibodi?
13
Proportion of rotavirus identification and
cumulative frequency by age group
Percentage
Age (Months)
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Clinical manifestation of rotavirus diarrhea
Signs and Symptoms
Tenesmus
Abdominal pain
Mucous-bloody stool
Watery stool
Nausea -Vomit
Fever
Percentage
N 713 cases
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Clinical manifestation and rotavirus
identification in acute diarrhea cases
Rotavirus ve
Rotavirus -ve
SingsSymptoms
OR
(95CI)
(n713)
(n1,358)
Watery stool
475
754
(1.32,1.93)
1.60
Mucus-bloody stool
102
366
0.45
(0.36,0.58)
1.09
(0.88,1.35)
Fever
547
1,020
2.52
(2.06,3.07)
Nausea-vomiting
531
729
Abdominal pain
74
190
0.71
(0.54,0.95)
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Distribution of rotavirus serotype in diarrhea
illness
Percentage
Strain characterization 838 cases
Found mostly in 2003
Serotype
17
Burden estimation of Thailand, 2002

• p1 of rotavirus positive of hospitalized
  cases
• 42.97 (838 / 1,950)
• n1 Number of hospitalized diarrhea cases
• 131,360 50,418 of 506 report 38.38
  coverage
• N 0 to 5 years population 5,005,904

Burden of rotavirus diarrhea (p1 X n1) / N
Burden of rotavirus diarrhea Hospitalize
cases (42.97 X 131,360) / 5,005,904
11.28 per 1,000 population under 5
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Discussion and conclusion

• Proportion of hospitalized rotavirus-positive
  children was higher than previous studies (43 VS
  17-44), and much higher than diarrhea in
  communities (12, method presented elsewhere)
• Rapid changing of rotavirus serotype (type G1 in
  1988-1991, G9 in 2001-2002, and G2 plus G9 in
  2003)
• Estimated incidence rate of hospitalized
  rotavirus diarrhea in Thailand 11.28 per 1000
  population under 5
• The surveillance had good enrollment (60) and
  high specimen collection (94). Long term
  surveillance should provide rotavirus trend in
  Thailand