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Freitas, A. R. R.

Publications and source records attributed to Freitas, A. R. R..

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Excess deaths associated with the chikungunya epidemic of 2014 in Jamaica were higher among children under 5 and over 40 years of age, an analysis based on official data.

We assessed the excess of all causes of mortality by age groups during the chikungunya epidemics in Jamaica, 2014. Excess mortality was estimated by subtracting deaths observed in 2014 from that expected based on the average mortality rate of 2012-2013, with confidence interval of 99%.\n\nOverall mortality 91.9 / 100,000 population, 2,499 additional deaths than expected coincided with the peak of the epidemic, there was a strong correlation between the monthly incidence and the excess of deaths (Spearman Rho = 0.939; p <0.005). No other significant epidemiological phenomenon occurred on that island that could explain this increase in mortality. Thus, we suggest that mortality associated with chikungunya is underestimated in Jamaica, as in other countries.\n\nThe excess of deaths could be a strategic tool for the epidemiological surveillance of chikungunya as it has already been used in influenza and respiratory syncytial.

epidemiology

Excess mortality in Guadeloupe and Martinique, islands of the French West Indies, during the chikungunya epidemic of 2014

In some chikugunya epidemics, deaths are not fully captured by the traditional surveillance system, based on case reports and death reports. This is a time series study to evaluate the excess of mortality associated with epidemic of chikungunya virus (CHIKV) in Guadeloupe and Martinique, Antilles, 2014. The population (total 784,097 inhabitants) and mortality data estimated by sex and age were accessed at the Institut National de la Statistique et des Etudes Economiques - France. Age adjusted mortality rates were calculated also in Reunion, Indian Ocean for comparison. Epidemiological data on CHIKV (cases, hospitalizations, and deaths) were obtained in the official epidemiological reports of the Cellule de Institut de Veille Sanitaire - France. The excess of deaths for each month in 2014 and 2015 was the difference between the expected and observed deaths for all age groups, considering the 99% confidence interval threshold. Pearson coefficient of correlation between monthly excess of deaths and reported cases of chikungunya show a strong correlation (R = 0.81, p <0.005), also with a 1-month lag (R = 0.87, p <0.001), and between monthly rates of hospitalization for CHIKV and the excess of deaths with a delay of 1 month (R = 0.87, p <0.0005).The peak of the epidemic occurred in the month with the highest mortality, returning to normal soon after the end of the CHIKV epidemic. The overall mortality estimated by this method (639 deaths) was about 4 times greater than that obtained through death declarations (160 deaths). Excess mortality increased with age. Although etiological diagnosis of all deaths associated with CHIKV infection is not possible, already well-known statistical tools can contribute to an evaluation of the impact of this virus on the mortality and morbidity in the different age groups.

epidemiology

Excess Mortality Related To Chikungunya Epidemics In The Context Of Co-circulation Of Other Arboviruses In Brazil

Chikungunya is an emerging arbovirus that reached the Western Hemisphere at the end of 2013. Studies conducted in Indie Ocean and India suggest that many of deaths associated with chikungunya cannot be recognized by passive surveillance system. The occurrence of these deaths can be inferred by an increase in the overall mortality observed during chikungunya epidemics. To evaluate the mortality associated with chikungunya epidemics in Brazil, we studied monthly mortality by age group comparing the pre-chikungunya period with the chikungunya epidemic period in the most affected states of Brazil. We obtained official data from National System of Notifiable Diseases (SINAN) and Mortality Information System (SIM), both maintained by the Ministry of Health. It was possible to identify a significant increase in all-cause mortality rate during chikungunya epidemics, there was no similar mortality in previous years, even during dengue epidemics. We estimated an excess of 4,842 deaths in Pernambuco during the chikungunya epidemics (51.4/100,000 inhabitants), the most affected age groups were the elderly and under 1 year of age, the same pattern occurred in all states. Further studies at other sites are needed to confirm the association between increased mortality and chikungunya epidemics. If these findings are confirmed, it will be necessary to revise guidelines to recognize the real mortality associated with chikungunya and to improve therapeutic approaches and protective measures in the most vulnerable groups.

epidemiology