A statistical analysis of the seasonality in pulmonary tuberculosis
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The present study examines whether pulmonary tuberculosis (PTB) has an annual seasonal pattern. A mathematical model is also obtained to forecast the pattern of incidence. The data for the study are the cases of PTB reported throughout Spain, published in the Epidemiology Bulletin by the Carlos III Health Center of the Spanish Ministry of Health in a 26-year period, 1971–1996. The analytical results show that the low rates in tuberculosis notifications over the period 1971–1981 have changed, halting in 1982 and reversing with high incidence from 1983 onwards. An annual seasonal pattern was also shown with higher incidence during summer and autumn. With the mathematical model we predicted the disease behaviour in 1997 and the results were compared to the reported cases. In Spain, as in several industrialised countries, the reason for this recent increase in the number of reported cases is, mainly, the human immunodeficiency virus (HIV) infection. The seasonal trend, with higher incidence in winter, can be attributed to the increase in indoor activities, much more common than in a warm climate. The tubercle bacilli expelled from infected persons in a room with closed windows may remain infectious for a long time, increasing the risk of exposure of healthy persons to the bacilli. As the preclinical period, from exposure to clinical onset, may be of several weeks, the high incidence in spring would be explained. Moreover, in winter and spring the infections of viral aetiology, like flu, are more frequent and cause immunological deficiency which is another reason for the seasonal trend observed. An incidence greater than that foreseen by the mathematical model would express a failure in epidemiologic surveillance, and thus the results of this study may be used to assess a quality of the preventive measures.
- Raviglione MC, Sudre P, Rieder HL, Spinaci S, Kochi A. Secular trends of tuberculosis in western Europe. Bull WHO 1993; 71: 297-306.
- Rieder HL. Misbehaviour of a dying epidemic: A call for less speculation and better surveillance. Tubercle and Lung Disease 1992; 73: 181-183.
- Narain JP, Raviglione MC, Kochi A. HIV-associated tuberculosis in developing countries: Epidemiology and strategies for prevention. Tubercle and Lung Disease 1992; 73: 311-321.
- Snider DE Jr, Roper WI. The new tuberculosis. New Eng J Med 1992; 326: 703-705.
- Brudney K, Dobkins J. Resurgent tuberculosis in New York City. Human immunodeficiency virus, homeless, and the decline of tuberculosis control program. Am Rev Resp Disease 1991; 144: 745-749.
- Raviglione MC, Snider DE, Kochi A. Global epidemiology of tuberculosis. Morbidity and mortality of a worldwide epidemic. JAMA 1995; 273: 220-226.
- Ministerio de Sanidad y Consumo. Informe epidemiológico 1992. Boletín Epidemiolóco y Microbiológico 1993; 1(Suppl. 1).
- March P. Situación actual de la tuberculosis en españa. Med Clin (Barc) 1991; 97: 463-472.
- Box G, Jenkins G. Time series analysis forecasting and control. San Francisco: Holden Day, 1976.
- Helfenstein U. Box-Jenkins modelling of some viral infections diseases. Statist In Med 1986; 5: 37-47.
- Zaidi A, Schnell D, Reynolds G. Time series analysis of syphilis surveillance data. Statist In Med 1989; 8: 353-362.
- Schnell D, Zaidi A, Reynolds G. A time series analysis of gonorrhoea surveillance data. Statist In Med 1989; 8: 343-352.
- Ríos M, García JM, Cubedo M, Pérez D. Análisis de Series temporales en la epidemiología de la fiebre ti-foidea en españa. Med Clín (Barc) 1996; 106: 686-689.
- Fuller WA. Introduction to statistical time series. New York: John Wiley, 1976.
- Diggle PJ. Time series, a biostatistical introduction. Oxford: Clarendon Press, 1990.
- Cryer JD. Time series analysis. Boston: Duxbury Press, 1985.
- Catalano R, Serxner S. Time series designs of potential interest to epidemiologist. Am J Epidemiol 1987; 126: 724-731.
- Crabtree B, Ray S, Schmidt P, O'Connor P, Schmidt D. The individual over time: Time series applications in health care research. J Clin Epidemiol 1990; 43: 241-260.
- Ministerio de Sanidad y Consumo. Bol Epidemiol Semanal, Vol 6. 1998; 1: 3-4.
- Mateo S, Cano R, Garcia C. Changing epidemiology of meningococcal disease in Spain 1989-1997. Eurosur veillance 1997; 2: 71-74.
- A statistical analysis of the seasonality in pulmonary tuberculosis
European Journal of Epidemiology
Volume 16, Issue 5 , pp 483-488
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- Kluwer Academic Publishers
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- Pulmonary tuberculosis (PTB)
- Time series
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