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Complex temporal climate signals drive the emergence of human water-borne disease.

Morris A, Gozlan RE, Hassani H, Andreou D, Couppié P, Guégan JF - Emerg Microbes Infect (2014)

Bottom Line: Predominantly occurring in developing parts of the world, Buruli ulcer is a severely disabling mycobacterium infection which often leads to extensive necrosis of the skin.While the exact route of transmission remains uncertain, like many tropical diseases, associations with climate have been previously observed and could help identify the causative agent's ecological niche.From this, it was possible to postulate for the first time that outbreaks of Buruli ulcer can be triggered by combinations of rainfall patterns occurring on a long (i.e., several years) and short (i.e., seasonal) temporal scale, in addition to stochastic events driven by the El Niño-Southern Oscillation that may disrupt or interact with these patterns.

View Article: PubMed Central - PubMed

Affiliation: Bournemouth University, Dorset BH12 5BB , UK ; UMR MIVEGEC, IRD-CNRS-Universités de Montpellier 1 et 2, Centre IRD de Montpellier, 34394 Montpellier cedex 5 , France.

ABSTRACT
Predominantly occurring in developing parts of the world, Buruli ulcer is a severely disabling mycobacterium infection which often leads to extensive necrosis of the skin. While the exact route of transmission remains uncertain, like many tropical diseases, associations with climate have been previously observed and could help identify the causative agent's ecological niche. In this paper, links between changes in rainfall and outbreaks of Buruli ulcer in French Guiana, an ultraperipheral European territory in the northeast of South America, were identified using a combination of statistical tests based on singular spectrum analysis, empirical mode decomposition and cross-wavelet coherence analysis. From this, it was possible to postulate for the first time that outbreaks of Buruli ulcer can be triggered by combinations of rainfall patterns occurring on a long (i.e., several years) and short (i.e., seasonal) temporal scale, in addition to stochastic events driven by the El Niño-Southern Oscillation that may disrupt or interact with these patterns. Long-term forecasting of rainfall trends further suggests the possibility of an upcoming outbreak of Buruli ulcer in French Guiana.

No MeSH data available.


Related in: MedlinePlus

Cross-correlation analysis between rainfall seasonal components extracted by SSA and seasonal IMF series of Buruli ulcer. Four-month component and (A) first IMF, (B) second IMF, (C) third IMF. Six-month component and (D) first IMF, (E) Second IMF, (F) third IMF. Twelve-month component and (G) first IMF, (H) second IMF, (I) third IMF. Dashed horizontal blue lines in all panels represent the 95% confidence limit; black vertical lines which go beyond the dashed line can be considered non-random cohering oscillations between the two time series being assessed, with the lag period between an above average oscillation in the first time series and a subsequent above average oscillation in the second shown on the X-axis.
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fig8: Cross-correlation analysis between rainfall seasonal components extracted by SSA and seasonal IMF series of Buruli ulcer. Four-month component and (A) first IMF, (B) second IMF, (C) third IMF. Six-month component and (D) first IMF, (E) Second IMF, (F) third IMF. Twelve-month component and (G) first IMF, (H) second IMF, (I) third IMF. Dashed horizontal blue lines in all panels represent the 95% confidence limit; black vertical lines which go beyond the dashed line can be considered non-random cohering oscillations between the two time series being assessed, with the lag period between an above average oscillation in the first time series and a subsequent above average oscillation in the second shown on the X-axis.

Mentions: The reconstructed rainfall series has a corresponding relationship with both the second and third IMF (Figures 7I and 7J), suggesting that an above average level of precipitation contributes to an above average spike in bi-annual BU cases, and also the overall yearly number of cases. By looking at the SSA-derived components of rainfall against the IMF signatures of BU, it is possible to identify the exact rainfall components which are driving these spikes. The SSA-derived 4-month component correlated with no IMF signatures (Figures 8A–8C). Figures 8D–8F show the correlations of the first, second and third IMF signatures with the SSA-derived 6-month component (i.e., the strength of both the two wet seasons); a significant correlation is identified with the bi-annual BU cases (second IMF) with an approximate 5-month lag; therefore, because of the average reported incubation periods of 3–5 months41 and the lag time of several weeks before diagnosis, the two spikes in cases per year are most likely to be driven by the strength of the two spikes in rainfall per year rather than the two dry seasons. The 12-month component which is a measure of the total rainfall per year did not correlate with any seasonal IMF signatures (Figures 8G and 8H), but as expected correlated with the overall level of BU per year (Figure 8I).


Complex temporal climate signals drive the emergence of human water-borne disease.

Morris A, Gozlan RE, Hassani H, Andreou D, Couppié P, Guégan JF - Emerg Microbes Infect (2014)

Cross-correlation analysis between rainfall seasonal components extracted by SSA and seasonal IMF series of Buruli ulcer. Four-month component and (A) first IMF, (B) second IMF, (C) third IMF. Six-month component and (D) first IMF, (E) Second IMF, (F) third IMF. Twelve-month component and (G) first IMF, (H) second IMF, (I) third IMF. Dashed horizontal blue lines in all panels represent the 95% confidence limit; black vertical lines which go beyond the dashed line can be considered non-random cohering oscillations between the two time series being assessed, with the lag period between an above average oscillation in the first time series and a subsequent above average oscillation in the second shown on the X-axis.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4150285&req=5

fig8: Cross-correlation analysis between rainfall seasonal components extracted by SSA and seasonal IMF series of Buruli ulcer. Four-month component and (A) first IMF, (B) second IMF, (C) third IMF. Six-month component and (D) first IMF, (E) Second IMF, (F) third IMF. Twelve-month component and (G) first IMF, (H) second IMF, (I) third IMF. Dashed horizontal blue lines in all panels represent the 95% confidence limit; black vertical lines which go beyond the dashed line can be considered non-random cohering oscillations between the two time series being assessed, with the lag period between an above average oscillation in the first time series and a subsequent above average oscillation in the second shown on the X-axis.
Mentions: The reconstructed rainfall series has a corresponding relationship with both the second and third IMF (Figures 7I and 7J), suggesting that an above average level of precipitation contributes to an above average spike in bi-annual BU cases, and also the overall yearly number of cases. By looking at the SSA-derived components of rainfall against the IMF signatures of BU, it is possible to identify the exact rainfall components which are driving these spikes. The SSA-derived 4-month component correlated with no IMF signatures (Figures 8A–8C). Figures 8D–8F show the correlations of the first, second and third IMF signatures with the SSA-derived 6-month component (i.e., the strength of both the two wet seasons); a significant correlation is identified with the bi-annual BU cases (second IMF) with an approximate 5-month lag; therefore, because of the average reported incubation periods of 3–5 months41 and the lag time of several weeks before diagnosis, the two spikes in cases per year are most likely to be driven by the strength of the two spikes in rainfall per year rather than the two dry seasons. The 12-month component which is a measure of the total rainfall per year did not correlate with any seasonal IMF signatures (Figures 8G and 8H), but as expected correlated with the overall level of BU per year (Figure 8I).

Bottom Line: Predominantly occurring in developing parts of the world, Buruli ulcer is a severely disabling mycobacterium infection which often leads to extensive necrosis of the skin.While the exact route of transmission remains uncertain, like many tropical diseases, associations with climate have been previously observed and could help identify the causative agent's ecological niche.From this, it was possible to postulate for the first time that outbreaks of Buruli ulcer can be triggered by combinations of rainfall patterns occurring on a long (i.e., several years) and short (i.e., seasonal) temporal scale, in addition to stochastic events driven by the El Niño-Southern Oscillation that may disrupt or interact with these patterns.

View Article: PubMed Central - PubMed

Affiliation: Bournemouth University, Dorset BH12 5BB , UK ; UMR MIVEGEC, IRD-CNRS-Universités de Montpellier 1 et 2, Centre IRD de Montpellier, 34394 Montpellier cedex 5 , France.

ABSTRACT
Predominantly occurring in developing parts of the world, Buruli ulcer is a severely disabling mycobacterium infection which often leads to extensive necrosis of the skin. While the exact route of transmission remains uncertain, like many tropical diseases, associations with climate have been previously observed and could help identify the causative agent's ecological niche. In this paper, links between changes in rainfall and outbreaks of Buruli ulcer in French Guiana, an ultraperipheral European territory in the northeast of South America, were identified using a combination of statistical tests based on singular spectrum analysis, empirical mode decomposition and cross-wavelet coherence analysis. From this, it was possible to postulate for the first time that outbreaks of Buruli ulcer can be triggered by combinations of rainfall patterns occurring on a long (i.e., several years) and short (i.e., seasonal) temporal scale, in addition to stochastic events driven by the El Niño-Southern Oscillation that may disrupt or interact with these patterns. Long-term forecasting of rainfall trends further suggests the possibility of an upcoming outbreak of Buruli ulcer in French Guiana.

No MeSH data available.


Related in: MedlinePlus