Annals of African Medicine

ORIGINAL ARTICLE
Year
: 2015  |  Volume : 14  |  Issue : 2  |  Page : 89--96

Development of a time-trend model for analyzing and predicting case-pattern of Lassa fever epidemics in Liberia, 2013-2017


Babasola O Olugasa1, Eugene A Odigie1, Mike Lawani2, Johnson F Ojo3 
1 Department of Veterinary Public Health and Preventive Medicine, Centre for Control and Prevention of Zoonoses, Faculty of Veterinary Medicine, Ibadan, Oyo State, Nigeria
2 Department of Epidemiology and Medical Statistics, Faculty of Public Health, College of Medicine, Ibadan, Oyo State, Nigeria
3 Department of Statistics, Faculty of Science, University of Ibadan, Ibadan, Oyo State, Nigeria

Correspondence Address:
Babasola O Olugasa
Centre for Control and Prevention of Zoonoses, Department of Veterinary Public Health and Preventive Medicine, 101 Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Oyo State
Nigeria

Objective: The objective was to develop a case-pattern model for Lassa fever (LF) among humans and derive predictors of time-trend point distribution of LF cases in Liberia in view of the prevailing under-reporting and public health challenge posed by the disease in the country. Materials and Methods: A retrospective 5 years data of LF distribution countrywide among humans were used to train a time-trend model of the disease in Liberia. A time-trend quadratic model was selected due to its goodness-of-fit (R2 = 0.89, and P < 0.05) and best performance compared to linear and exponential models. Parameter predictors were run on least square method to predict LF cases for a prospective 5 years period, covering 2013-2017. Results: The two-stage predictive model of LF case-pattern between 2013 and 2017 was characterized by a prospective decline within the South-coast County of Grand Bassa over the forecast period and an upward case-trend within the Northern County of Nimba. Case specific exponential increase was predicted for the first 2 years (2013-2014) with a geometric increase over the next 3 years (2015-2017) in Nimba County. Conclusion: This paper describes a translational application of the space-time distribution pattern of LF epidemics, 2008-2012 reported in Liberia, on which a predictive model was developed. We proposed a computationally feasible two-stage space-time permutation approach to estimate the time-trend parameters and conduct predictive inference on LF in Liberia.


How to cite this article:
Olugasa BO, Odigie EA, Lawani M, Ojo JF. Development of a time-trend model for analyzing and predicting case-pattern of Lassa fever epidemics in Liberia, 2013-2017.Ann Afr Med 2015;14:89-96


How to cite this URL:
Olugasa BO, Odigie EA, Lawani M, Ojo JF. Development of a time-trend model for analyzing and predicting case-pattern of Lassa fever epidemics in Liberia, 2013-2017. Ann Afr Med [serial online] 2015 [cited 2022 May 26 ];14:89-96
Available from: https://www.annalsafrmed.org/article.asp?issn=1596-3519;year=2015;volume=14;issue=2;spage=89;epage=96;aulast=Olugasa;type=0