Distribution of febrile patients with and without acute chikungunya infection by month, southern Sri Lanka, 2007.

<p>Distribution of febrile patients with and without acute chikungunya infection by month, southern Sri Lanka, 2007.</p

Alignment of the amino acid sequence surrounding the chikungunya virus E1-226 region.

<p>Amino acid sequence corresponding to the E1 gene was translated from the nucleotide sequences of the three Sri Lankan isolates and compared the amino acid sequences of the isolates described in Schuffennecker et al 2006, PLoS Med and Kumar et al 2008, JGV [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B10" target="_blank">10</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B11" target="_blank">11</a>]. Position E1-226 is highlighted (E1-226 corresponds to position 1035 in the polyprotein). </p

Presence of anti-chikungunya IgG by age (years) in febrile patients, southern Sri Lanka, 2007.

<p>Presence of anti-chikungunya IgG by age (years) in febrile patients, southern Sri Lanka, 2007.</p

Age-group specific WBC in patients with dengue, OFI and influenza in the first 72 hours of illness.

<p>Box and whiskers (maximum and minimum) indicate the mean and spread of WBC in the different groups of patients. Dotted line indicates threshold for leukopenia (WBC<4,500 cells/µL). ***indicates p<0.0001 as determined using the Mann Whitney U test.</p

Age-specific features of using fever and leukopenia for probable dengue diagnosis.

<p>Leukopenia is defined as WBC<4,500 cells/µxL.</p><p>AUC indicates area under the curve.</p><p>PPV and NPV denote positive and negative predictive values, respectively.</p><p>Values in parentheses are the 95% confidence intervals.</p

Age-specific features of probable dengue diagnosis using the WHO 1997 or 2009 classification schemes.

<p>PPV and NPV denote positive and negative predictive values, respectively.</p><p>Values in parentheses are the 95% confidence intervals.</p

Phylogenetic relationship of Sri Lankan chikungunya virus (CHIKV) isolates.

<p>Sequences corresponding to the CHIKV structural genes from the six Sri Lankan isolates were compared to published CHIKV sequences [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B6" target="_blank">6</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B8" target="_blank">8</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B10" target="_blank">10</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B11" target="_blank">11</a>,<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0082259#B16" target="_blank">16</a>]. Region of isolation is indicated by text color: West Africa (Red), Asia (Blue), East/South/Central Africa (Green), Reunion Island (Pink) and India/Sri Lanka (Orange). Isolates from the current study are indicated in bold-italics.</p

Age distribution of patients with and without acute chikungunya infection, southern Sri Lanka, 2007.

<p>Age distribution of patients with and without acute chikungunya infection, southern Sri Lanka, 2007.</p

Demographics of the hospitalized dengue cases with severe or non-severe dengue.

<p>Chi-square test with Yates' continuity correction was used except where indicated.</p><p>*Mann-Whitney U test.</p>#<p>One patient was admitted for a total of 37 days due to lack of a caregiver at home. Data from this patient was treated as an outlier and removed from analysis.</p

Laboratory parameters in dengue patients who received hospitalized or ambulatory care only.

<p>Shown are median values with the 25^th and 75^th percentiles in parentheses.</p><p>Chi-square test with Yates' continuity correction was used except where indicated.</p><p>*Mann Whitney U test.</p><p>∧Cp indicates crossover point on the real-time RT-PCR, which is a semi-quantitative indicator of viremia levels. Lower Cp values indicate higher viremia levels and vice versa.</p>#<p>IgG seropositivity indicates secondary dengue infection.</p><p>WBC indicates white blood cell count.</p