A locally initiated and executed measles outbreak response immunization campaign in the nylon health district, Douala Cameroon 2011

BackgroundPertussis control remains a challenge due to recently observed effects of waning immunity to acellular vaccine and suboptimal vaccine coverage. Multiple outbreaks have been reported in different ages worldwide. For certain outbreaks, public health authorities can launch an outbreak response immunization (ORI) campaign to control pertussis spread. We investigated effects of an outbreak response immunization targeting young adolescents in averting pertussis cases.MethodsWe developed an agent-based model for pertussis transmission representing disease mechanism, waning immunity, vaccination schedule and pathogen transmission in a spatially-explicit 500,000-person contact network representing a typical Canadian Public Health district. Parameters were derived from literature and calibration. We used published cumulative incidence and dose-specific vaccine coverage to calibrate the model’s epidemiological curves. We endogenized outbreak response by defining thresholds to trigger simulated immunization campaigns in the 10–14 age group offering 80% coverage. We ran paired simulations with and without outbreak response immunization and included those resulting in a single ORI within a 10-year span. We calculated the number of cases averted attributable to outbreak immunization campaign in all ages, in the 10–14 age group and in infants. The count of cases averted were tested using Mann–WhitneyUtest to determine statistical significance. Numbers needed to vaccinate during immunization campaign to prevent a single case in respective age groups were derived from the model. We varied adult vaccine coverage, waning immunity parameters, immunization campaign eligibility and tested stronger vaccination boosting effect in sensitivity analyses.Results189 qualified paired-runs were analyzed. On average, ORI was triggered every 26 years. On a per-run basis, there were an average of 124, 243 and 429 pertussis cases averted across all age groups within 1, 3 and 10 years of a campaign, respectively. During the same time periods, 53, 96, and 163 cases were averted in the 10–14 age group, and 6, 11, 20 in infants under 1 (p< 0.001, all groups). Numbers needed to vaccinate ranged from 49 to 221, from 130 to 519 and from 1,031 to 4,903 for all ages, the 10–14 age group and for infants, respectively. Most sensitivity analyses resulted in minimal impact on a number of cases averted.DiscussionOur model generated 30 years of longitudinal data to evaluate effects of outbreak response immunization in a controlled study. Immunization campaign implemented as an outbreak response measure among adolescents may confer benefits across all ages accruing over a 10-year period. Our inference is dependent on having an outbreak of significant magnitude affecting predominantly the selected age and achieving a comprehensive vaccine coverage during the campaign. Economic evaluations and comparisons with other control measures can add to conclusions generated by our work.

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Challenges related to resources mobilization for measles outbreak response: Madagascar experience during the 2018-2019 measles outbreak

Pan African Medical Journal ◽

10.11604/pamj.2020.36.304.24514 ◽

2020 ◽

Vol 36 ◽

Author(s):

Vincent Dossou Sodjinou ◽

Marcellin Mengouo Nimpa ◽

Alfred Douba ◽

Yolande Vuo Masembe ◽

Mireille Randria ◽

...

Keyword(s):

Outbreak Response ◽

Measles Outbreak

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Investigation of measles outbreak in Bangue health district: Challenges of control in an urban setting, Cameroon 2019

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2020.09.817 ◽

2020 ◽

Vol 101 ◽

pp. 313

Author(s):

M.N. Nanga Dampand ◽

A.V. Kouatchouang ◽

T. Djikeussi ◽

J. Lontsi ◽

S. Billong

Keyword(s):

Urban Setting ◽

Health District ◽

Measles Outbreak

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A US metropolitan county health department’s response to a measles outbreak in a childcare facility – challenges faced and lessons learned

Perspectives in Public Health ◽

10.1177/1757913920955201 ◽

2020 ◽

pp. 175791392095520

Author(s):

Diane Meyer ◽

Marc Trotochaud ◽

Lisa Ferguson ◽

Jennifer Vines ◽

Russell Barlow ◽

...

Keyword(s):

Public Health ◽

Health Department ◽

Lessons Learned ◽

Outbreak Response ◽

Public Health Community ◽

Local Public Health ◽

Measles Outbreak ◽

Health Community ◽

Childcare Facility ◽

Measles Outbreaks

Aims: In June 2018, the Multnomah County Health Department located in Portland, Oregon, US, responded to a measles exposure in a local childcare facility. This analysis describes lessons learned and challenges encountered during this measles response that may inform public health policy and help other local public health authorities prepare for measles outbreaks. These lessons will become increasingly important as measles cases continue to increase in both the US and abroad. Methods: A semi-structured videoconference interview was conducted with nine health department staff who were directly involved in the health department’s response to the measles outbreak. Interview notes were iteratively discussed between all authors to identify those outbreak response challenges and lessons learned that were generalizable to the broader public health community. Results: Some of the key challenges and lessons learned included the need for increased provider recognition and reporting of measles cases, difficulty in determining which staff and children to exclude from attending daycare during the 21-day postexposure monitoring period, determining who would be prioritized to receive immunoglobulin, and the need for childcare staff vaccine status requirements. Conclusion: Lessons from this response highlight important considerations for public health practitioners and policy makers. Given the relative severity of measles and the potential for spread in facilities that serve infants and young children, the public health community must continue to address key gaps through planning and policy.

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Time is of the essence: exploring a measles outbreak response vaccination in Niamey, Niger

Journal of The Royal Society Interface ◽

10.1098/rsif.2007.1038 ◽

2007 ◽

Vol 5 (18) ◽

pp. 67-74 ◽

Cited By ~ 51

Author(s):

R.F Grais ◽

A.J.K Conlan ◽

M.J Ferrari ◽

A Djibo ◽

A Le Menach ◽

...

Keyword(s):

Urban Setting ◽

World Health ◽

Outbreak Response ◽

High Coverage ◽

Measles Outbreak ◽

Potential Impact ◽

Individual Based Simulation ◽

Health Organization ◽

Age Range ◽

The Impact

The current World Health Organization recommendations for response during measles epidemics focus on case management rather than outbreak response vaccination (ORV) campaigns, which may occur too late to impact morbidity and mortality and have a high cost per case prevented. Here, we explore the potential impact of an ORV campaign conducted during the 2003–2004 measles epidemic in Niamey, Niger. We measured the impact of this intervention and also the potential impact of alternative strategies. Using a unique geographical, epidemiologic and demographic dataset collected during the epidemic, we developed an individual-based simulation model. We estimate that a median of 7.6% [4.9–8.9] of cases were potentially averted as a result of the outbreak response, which vaccinated approximately 57% (84 563 of an estimated 148 600) of children in the target age range (6–59 months), 23 weeks after the epidemic started. We found that intervening early (up to 60 days after the start of the epidemic) and expanding the age range to all children aged 6 months to 15 years may lead to a much larger (up to 90%) reduction in the number of cases in a West African urban setting like Niamey. Our results suggest that intervening earlier even with lower target coverage (approx. 60%), but a wider age range, may be more effective than intervening later with high coverage (more than 90%) in similar settings. This has important implications for the implementation of reactive vaccination interventions as they can be highly effective if the response is fast with respect to the spread of the epidemic.

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Peer Review #2 of "Evaluation of outbreak response immunization in the control of pertussis using agent-based modeling (v0.1)"

10.7287/peerj.2337v0.1/reviews/2 ◽

2016 ◽

Keyword(s):

Peer Review ◽

Agent Based Modeling ◽

Outbreak Response ◽

Agent Based ◽

Outbreak Response Immunization

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Controlling polio outbreak due to imported wild poliovirus in Indonesia: A success story

Paediatrica Indonesiana ◽

10.14238/pi49.4.2009.234-43 ◽

2009 ◽

Vol 49 (4) ◽

pp. 234 ◽

Cited By ~ 1

Author(s):

Sumarmo Poorwo Soedarmo ◽

Sidik Utoro

Keyword(s):

Acute Flaccid Paralysis ◽

Polio Eradication ◽

Outbreak Response ◽

Success Story ◽

Wild Poliovirus ◽

First Case ◽

Supplementary Immunization Activities ◽

Stool Samples ◽

Outbreak Response Immunization

Background As a WHO member state, Indonesia is committed toGlobal Polio Eradication. The last indigenous polio case was found in 1995. However, we faced a big challenge with the occurrence of polio outbreak, beginning with a polio case caused by imported wild poliovirus (WPV) type 1 in Sukabumi in 2005. The virus was originated from Sudan and imported to Indonesia through Saudi Arabia. The outbreak ended with totally 305 cases throughout the country. The last one occurred on 20 February 2006 in Aceh Tenggara District, Nanggroe Aceh Darussalam Province. In addition and separated from the WPV type 1 outbreak, in August 2005, four Acute Flaccid Paralysis (AFP) cases with type 1 Vaccine Derived Poliovirus (VDPV) in stool samples were identified in Madura, East Java Province. The first case was on 9 June 2005 and ended with 45 cases in Madura and another case in Probolinggo District, East Jawa.Objective To report a success of controlling outbreak of importedWPV in Indonesia.Methods Outbreak Response Immunization (ORI) and mopup immunization were conducted immediately. To completelystop the transmission, three rounds of National ImmunizationDays (NIDs) were conducted in 2005 (August, September, andNovember). Some more Supplementary Immunization Activities(SIAs) were conducted in 2006 (mop up in January, NIDs inFebruary and early April, mop ups in June and August 2006).For the VDPV outbreak, ORI of 18,880 children in 83 villagestook place during the first week of August, beside three roundsofNIDs in 2005.Results All activities resulted in satisfactorily coverage, whereeach round always exceeded 95%.Conclusions Those activities were conducted successfully andproven to be effective to stop the outbreak. Then again, Indonesia can be a polio free country in the coming years.

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Strategies to Improve Coverage of Typhoid Conjugate Vaccine (TCV) Immunization Campaign in Karachi, Pakistan

Vaccines ◽

10.3390/vaccines8040697 ◽

2020 ◽

Vol 8 (4) ◽

pp. 697

Author(s):

Farah Naz Qamar ◽

Rabab Batool ◽

Sonia Qureshi ◽

Miqdad Ali ◽

Tahira Sadaf ◽

...

Keyword(s):

Community Engagement ◽

Conjugate Vaccine ◽

Vaccination Campaign ◽

Vaccine Hesitancy ◽

Drug Resistant ◽

Key Factors ◽

Outbreak Response ◽

Extensively Drug Resistant ◽

Mass Immunization ◽

Immunization Campaign

The emergence and spread of extensively drug-resistant (XDR) typhoid in Karachi, Pakistan led to an outbreak response in Lyari Town, Karachi utilizing a mass immunization campaign with typhoid conjugate vaccine (TCV), Typbar TCV®. The mass immunization campaign, targeted Lyari Town, Karachi, one of the worst affected towns during the XDR typhoid outbreak. Here we describe the strategies used to improve acceptance and coverage of Typbar TCV in Lyari Town, Karachi. The mass immunization campaign with Typbar TCV was started as a school- and hospital-based vaccination campaign targeting children between the age of 6 months to 15 years old. A dose of 0.5 mL Typbar TCV was administered intramuscularly. A mobile vaccination campaign was added to cope with high absenteeism and non-response from parents in schools and to cover children out of school. Different strategies were found to be effective in increasing the vaccination coverage and in tackling vaccine hesitancy. Community engagement was the most successful strategy to overcome refusals and helped to gain trust in the newly introduced vaccine. Community announcements and playing typhoid jingles helped to increase awareness regarding the ongoing typhoid outbreak. Mop-up activity in schools was helpful in increasing coverage. Networking with locally active groups, clubs and community workers were found to be the key factors in decreasing refusals.

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