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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 (A) ENSO and reconstructed rainfall time series from SSA. (B) ENSO and original rainfall time series. ENSO and (C) first IMF from Buruli ulcer cases, (D) second IMF, (E) third IMF, (F) fourth IMF, (G) fifth IMF. Reconstructed rainfall series and (H) first IMF; (I) second IMF; (J) third IMF; (K) fourth IMF; (L) fifth 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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fig7: Cross-correlation analysis between (A) ENSO and reconstructed rainfall time series from SSA. (B) ENSO and original rainfall time series. ENSO and (C) first IMF from Buruli ulcer cases, (D) second IMF, (E) third IMF, (F) fourth IMF, (G) fifth IMF. Reconstructed rainfall series and (H) first IMF; (I) second IMF; (J) third IMF; (K) fourth IMF; (L) fifth 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: SST did not correlate with the SSA derived rainfall series (Figure 7A), but did corresponded with rainfall before SSA was applied (Figure 7B), suggesting that SST spikes cause higher levels of unpredictable rainfall anomalies, which during SSA analysis were classified as ‘noise' or stochastic events. SST also corresponded with the first IMF of BU cases (Figure 7C), which was similarly classified as noise. This may mean that SST creates rainfall anomalies, which cause high levels of BU but do not follow any set seasonal or long-term patterns (i.e., random one off events). SST fluctuations further matched with inter-annual variation of BU cases with long lag periods, suggesting that the total number of cases over these periods is increased by the influence of SST-driven anomalies (Figures 7D–7G). In particular the fourth IMF, where a below average SST (La Niña) value produces a higher than average level of BU cases over 2 years after a lag time of approximately 18 months (Figure 7F). Conversely, a peak in SST (El Niño) creates a decline in the 4-year oscillation of BU cases (Figure 7G).


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 (A) ENSO and reconstructed rainfall time series from SSA. (B) ENSO and original rainfall time series. ENSO and (C) first IMF from Buruli ulcer cases, (D) second IMF, (E) third IMF, (F) fourth IMF, (G) fifth IMF. Reconstructed rainfall series and (H) first IMF; (I) second IMF; (J) third IMF; (K) fourth IMF; (L) fifth 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

fig7: Cross-correlation analysis between (A) ENSO and reconstructed rainfall time series from SSA. (B) ENSO and original rainfall time series. ENSO and (C) first IMF from Buruli ulcer cases, (D) second IMF, (E) third IMF, (F) fourth IMF, (G) fifth IMF. Reconstructed rainfall series and (H) first IMF; (I) second IMF; (J) third IMF; (K) fourth IMF; (L) fifth 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: SST did not correlate with the SSA derived rainfall series (Figure 7A), but did corresponded with rainfall before SSA was applied (Figure 7B), suggesting that SST spikes cause higher levels of unpredictable rainfall anomalies, which during SSA analysis were classified as ‘noise' or stochastic events. SST also corresponded with the first IMF of BU cases (Figure 7C), which was similarly classified as noise. This may mean that SST creates rainfall anomalies, which cause high levels of BU but do not follow any set seasonal or long-term patterns (i.e., random one off events). SST fluctuations further matched with inter-annual variation of BU cases with long lag periods, suggesting that the total number of cases over these periods is increased by the influence of SST-driven anomalies (Figures 7D–7G). In particular the fourth IMF, where a below average SST (La Niña) value produces a higher than average level of BU cases over 2 years after a lag time of approximately 18 months (Figure 7F). Conversely, a peak in SST (El Niño) creates a decline in the 4-year oscillation of BU cases (Figure 7G).

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