Seasonal Influenza Vaccine Effectiveness Study in Kenya

NCT ID: NCT01432340

Last Updated: 2024-09-20

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 10000 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2010-06-30
• Study Completion Date: 2014-03-18

Brief Summary

Influenza is an important cause of acute respiratory infections (ARI) worldwide. Seasonal influenza causes an estimated 250,000-500,000 deaths and 3-5 million severe illnesses each year (WHO, 2009), and pandemic 2009 H1N1 influenza has caused morbidity and mortality worldwide. In Kenya, influenza accounts for up to 50% of all ARI during the peak influenza season, based on Kenyan Ministry of Public Health and Sanitation and KEMRI/CDC surveillance data. Influenza vaccine has been shown to reduce influenza-associated ARIs in developed countries. However, little is know about the effectiveness of influenza vaccine in the developing world. In Kenya, a commercial trivalent injectable vaccine is licensed, but less than 30,000 doses are sold annually. The International Emerging Infections Program (IEIP) under KEMRI/CDC currently conducts population-based disease surveillance (PBDS) for severe acute respiratory illness (SARI) and influenza-like illness (ILI) in two sites in Kenya, Lwak (Nyanza province) and Kibera (Nairobi). The investigators propose to conduct a three-year influenza vaccine effectiveness study using the commercially available southern hemisphere seasonal vaccine for 2010, which includes the pandemic 2009 H1N1 component, and for 2011 and 2012. The study will evaluate the effectiveness of the vaccine in preventing laboratory-confirmed influenza, non-specific ARIs at the clinic and household level, and secondary influenza infection and secondary ARIs. Our study hypothesis is: Immunizing children with influenza vaccine will decrease influenza-associated acute respiratory infections among children and may reduce the number of non-specific acute respiratory infections in vaccinated children and their household contacts.

Detailed Description

Vaccine will be donated by Sanofi Pasteur in a quantity large enough to vaccinate the eligible population. Vaccine will be made available to infants from 6 months of age through children up to 10 years old. This includes an age group that is at high risk for severe outcomes (<5 years) and an age group (school-age children, 5-10) that is considered most likely to spread the infection.

Ascertainment of Influenza Illness:

Primary Outcome Measure

• Laboratory-confirmed influenza infection

Secondary outcome measures

• Medically attended ILI, SARI
• Community-reported ILI SARI
• Laboratory-confirmed influenza, medically attended ILI and SARI, and community-reported ILI and SARI in non-immunized household members

In Lwak and Kibera, field workers visit households weekly and encourage residents to go to the free clinic if they have respiratory symptoms. Currently, from KEMRI/CDC surveillance data, in Kibera, approximately 57 % of people in the catchment area seek medical care for ILI (Range: 62% children - 52% adults) and of those people who seek care, 72% seek care at Tabitha clinic. In Lwak, approximately 77% of people in the catchment area seek medical care for ILI (Range: 75% children - 80% adults) and of those people who seek care, 34% seek care at Lwak clinic.

The surveillance for ILI and SARI will continue as usual, with weekly field worker (also called community interviewer) household visits, clinic-based surveillance for ILI and SARI at Tabitha clinic and Lwak clinic, and sampling of all patients who meet the case definition for ILI and SARI

Conditions

Influenza; Influenza Like Illness; Severe Acute Respiratory Illness

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Study Groups

Vaccinated group

Children between 6months- 10years of age who have received the influenza vaccine

Seasonal influenza vaccine

Intervention Type: BIOLOGICAL

annual recommended Southern Hemisphere vaccine

Unvaccinated group

Eligible children between 6months and 10years who didn't receive the influenza vaccine

Seasonal influenza vaccine

Intervention Type: BIOLOGICAL

annual recommended Southern Hemisphere vaccine

Interventions

Seasonal influenza vaccine

annual recommended Southern Hemisphere vaccine

Intervention Type: BIOLOGICAL

Other Intervention Names

Vaxigrip

Eligibility Criteria

Inclusion Criteria

• Age 6months -10 years
• Enrolled in the IEIP morbidity study

Exclusion Criteria

• Age less than 6 months or greater than or equal to 11 years
• Not enrolled in the IEIP morbidity study

• Minimum Eligible Age: 6 Months
• Maximum Eligible Age: 10 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Kenya Ministry of Health

OTHER_GOV

Sponsor Role: collaborator

Kenya Medical Research Institute

OTHER

Sponsor Role: collaborator

Sanofi Pasteur, a Sanofi Company

INDUSTRY

Sponsor Role: collaborator

Gideon Emukule

FED

Sponsor Role: lead

Responsible Party

Gideon Emukule

East Africa Influenza Program Director

Responsibility Role: SPONSOR_INVESTIGATOR

Principal Investigators

Mark A Katz, MD

Role: PRINCIPAL_INVESTIGATOR

Center for Disease Control and Prevention-Kenya

Robert Breiman, MD

Role: PRINCIPAL_INVESTIGATOR

Centers for Disease Control and Prevention

Joshua Mott, PhD

Role: PRINCIPAL_INVESTIGATOR

Centers for Disease Control and Prevention

Locations

KEMRI/CDC- IEIP surveillance-Asembo

Kisumu, Western, Kenya

KEMRI/CDC IEIP surveillance- Kibera

Nairobi, , Kenya

Countries

Kenya

References

World Health Organization. Acute Respiratory Infections (Update September 2009). 2009. Available at http://www.who.int/vaccine_research/diseases/ari/en/print.html

Reference Type: BACKGROUND

Williams BG, Gouws E, Boschi-Pinto C, Bryce J, Dye C. Estimates of world-wide distribution of child deaths from acute respiratory infections. Lancet Infect Dis. 2002 Jan;2(1):25-32. doi: 10.1016/s1473-3099(01)00170-0.

Reference Type: BACKGROUND

PMID: 11892493 (View on PubMed)

Viboud C, Alonso WJ, Simonsen L. Influenza in tropical regions. PLoS Med. 2006 Apr;3(4):e89. doi: 10.1371/journal.pmed.0030089. Epub 2006 Mar 7.

Reference Type: BACKGROUND

PMID: 16509764 (View on PubMed)

Belongia EA, Kieke BA, Donahue JG, Greenlee RT, Balish A, Foust A, Lindstrom S, Shay DK; Marshfield Influenza Study Group. Effectiveness of inactivated influenza vaccines varied substantially with antigenic match from the 2004-2005 season to the 2006-2007 season. J Infect Dis. 2009 Jan 15;199(2):159-67. doi: 10.1086/595861.

Reference Type: BACKGROUND

PMID: 19086915 (View on PubMed)

Center for Disease Control. ACIP Provisional Recommendations for the Use of Influenza Vaccines, March 2, 2010. Available at http://www.immunize.org/acip/

Reference Type: BACKGROUND

Other Identifiers

CDC-NCIRD-5933

Identifier Type: -

Identifier Source: org_study_id