Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice
Abstract Background Cholera is a major public health concern in displaced-person camps, which often contend with overcrowding and scarcity of resources. Maela, the largest and longest-standing refugee camp in Thailand, located along the Thai-Burmese border, experienced four cholera outbreaks between...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2019-12-01
|
| Series: | BMC Infectious Diseases |
| Subjects: | |
| Online Access: | https://doi.org/10.1186/s12879-019-4688-6 |
| _version_ | 1818952401211621376 |
|---|---|
| author | Joshua Havumaki Rafael Meza Christina R. Phares Kashmira Date Marisa C. Eisenberg |
| author_facet | Joshua Havumaki Rafael Meza Christina R. Phares Kashmira Date Marisa C. Eisenberg |
| author_sort | Joshua Havumaki |
| collection | DOAJ |
| description | Abstract Background Cholera is a major public health concern in displaced-person camps, which often contend with overcrowding and scarcity of resources. Maela, the largest and longest-standing refugee camp in Thailand, located along the Thai-Burmese border, experienced four cholera outbreaks between 2005 and 2010. In 2013, a cholera vaccine campaign was implemented in the camp. To assist in the evaluation of the campaign and planning for subsequent campaigns, we developed a mathematical model of cholera in Maela. Methods We formulated a Susceptible-Infectious-Water-Recovered-based transmission model and estimated parameters using incidence data from 2010. We next evaluated the reduction in cases conferred by several immunization strategies, varying timing, effectiveness, and resources (i.e., vaccine availability). After the vaccine campaign, we generated case forecasts for the next year, to inform on-the-ground decision-making regarding whether a booster campaign was needed. Results We found that preexposure vaccination can substantially reduce the risk of cholera even when <50% of the population is given the full two-dose series. Additionally, the preferred number of doses per person should be considered in the context of one vs. two dose effectiveness and vaccine availability. For reactive vaccination, a trade-off between timing and effectiveness was revealed, indicating that it may be beneficial to give one dose to more people rather than two doses to fewer people, given that a two-dose schedule would incur a delay in administration of the second dose. Forecasting using realistic coverage levels predicted that there was no need for a booster campaign in 2014 (consistent with our predictions, there was not a cholera epidemic in 2014). Conclusions Our analyses suggest that vaccination in conjunction with ongoing water sanitation and hygiene efforts provides an effective strategy for controlling cholera outbreaks in refugee camps. Effective preexposure vaccination depends on timing and effectiveness. If a camp is facing an outbreak, delayed distribution of vaccines can substantially alter the effectiveness of reactive vaccination, suggesting that quick distribution of vaccines may be more important than ensuring every individual receives both vaccine doses. Overall, this analysis illustrates how mathematical models can be applied in public health practice, to assist in evaluating alternative intervention strategies and inform decision-making. |
| first_indexed | 2024-12-20T09:49:47Z |
| format | Article |
| id | doaj.art-3bce0918bac1473f92ff9e3d6fbddf55 |
| institution | Directory Open Access Journal |
| issn | 1471-2334 |
| language | English |
| last_indexed | 2024-12-20T09:49:47Z |
| publishDate | 2019-12-01 |
| publisher | BMC |
| record_format | Article |
| series | BMC Infectious Diseases |
| spelling | doaj.art-3bce0918bac1473f92ff9e3d6fbddf552022-12-21T19:44:38ZengBMCBMC Infectious Diseases1471-23342019-12-0119111710.1186/s12879-019-4688-6Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practiceJoshua Havumaki0Rafael Meza1Christina R. Phares2Kashmira Date3Marisa C. Eisenberg4Department of Epidemiology, School of Public Health, University of MichiganDepartment of Epidemiology, School of Public Health, University of MichiganUS Centers for Disease Control and Prevention; National Center for Emerging and Zoonotic Infectious Diseases; Division of Global Migration and Quarantine and PreventionUS Centers for Disease Control and Prevention; Global Immunization Division - Center for Global HealthDepartment of Epidemiology, School of Public Health, University of MichiganAbstract Background Cholera is a major public health concern in displaced-person camps, which often contend with overcrowding and scarcity of resources. Maela, the largest and longest-standing refugee camp in Thailand, located along the Thai-Burmese border, experienced four cholera outbreaks between 2005 and 2010. In 2013, a cholera vaccine campaign was implemented in the camp. To assist in the evaluation of the campaign and planning for subsequent campaigns, we developed a mathematical model of cholera in Maela. Methods We formulated a Susceptible-Infectious-Water-Recovered-based transmission model and estimated parameters using incidence data from 2010. We next evaluated the reduction in cases conferred by several immunization strategies, varying timing, effectiveness, and resources (i.e., vaccine availability). After the vaccine campaign, we generated case forecasts for the next year, to inform on-the-ground decision-making regarding whether a booster campaign was needed. Results We found that preexposure vaccination can substantially reduce the risk of cholera even when <50% of the population is given the full two-dose series. Additionally, the preferred number of doses per person should be considered in the context of one vs. two dose effectiveness and vaccine availability. For reactive vaccination, a trade-off between timing and effectiveness was revealed, indicating that it may be beneficial to give one dose to more people rather than two doses to fewer people, given that a two-dose schedule would incur a delay in administration of the second dose. Forecasting using realistic coverage levels predicted that there was no need for a booster campaign in 2014 (consistent with our predictions, there was not a cholera epidemic in 2014). Conclusions Our analyses suggest that vaccination in conjunction with ongoing water sanitation and hygiene efforts provides an effective strategy for controlling cholera outbreaks in refugee camps. Effective preexposure vaccination depends on timing and effectiveness. If a camp is facing an outbreak, delayed distribution of vaccines can substantially alter the effectiveness of reactive vaccination, suggesting that quick distribution of vaccines may be more important than ensuring every individual receives both vaccine doses. Overall, this analysis illustrates how mathematical models can be applied in public health practice, to assist in evaluating alternative intervention strategies and inform decision-making.https://doi.org/10.1186/s12879-019-4688-6CholeraRefugee campVaccinationMathematical modeling |
| spellingShingle | Joshua Havumaki Rafael Meza Christina R. Phares Kashmira Date Marisa C. Eisenberg Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice BMC Infectious Diseases Cholera Refugee camp Vaccination Mathematical modeling |
| title | Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice |
| title_full | Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice |
| title_fullStr | Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice |
| title_full_unstemmed | Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice |
| title_short | Comparing alternative cholera vaccination strategies in Maela refugee camp: using a transmission model in public health practice |
| title_sort | comparing alternative cholera vaccination strategies in maela refugee camp using a transmission model in public health practice |
| topic | Cholera Refugee camp Vaccination Mathematical modeling |
| url | https://doi.org/10.1186/s12879-019-4688-6 |
| work_keys_str_mv | AT joshuahavumaki comparingalternativecholeravaccinationstrategiesinmaelarefugeecampusingatransmissionmodelinpublichealthpractice AT rafaelmeza comparingalternativecholeravaccinationstrategiesinmaelarefugeecampusingatransmissionmodelinpublichealthpractice AT christinarphares comparingalternativecholeravaccinationstrategiesinmaelarefugeecampusingatransmissionmodelinpublichealthpractice AT kashmiradate comparingalternativecholeravaccinationstrategiesinmaelarefugeecampusingatransmissionmodelinpublichealthpractice AT marisaceisenberg comparingalternativecholeravaccinationstrategiesinmaelarefugeecampusingatransmissionmodelinpublichealthpractice |