Median values and interquartile range in parentheses for white blood cell (WBC) and differential counts for complete WBC, neutrophils, lymphocytes, and platelets by CHIKF positivity and age group.

<p>Median values and interquartile range in parentheses for white blood cell (WBC) and differential counts for complete WBC, neutrophils, lymphocytes, and platelets by CHIKF positivity and age group.</p

Signs and symptoms recorded for CHIKF-positive (and CHIKF-negative) patients for whom complete blood counts were ordered between July 2014 and August 2014 at Hospital Buen Samaritano, La Romana, Dominican Republic.

<p>Signs and symptoms recorded for CHIKF-positive (and CHIKF-negative) patients for whom complete blood counts were ordered between July 2014 and August 2014 at Hospital Buen Samaritano, La Romana, Dominican Republic.</p

Distribution of total suspected cases of CHIKF reported in the Dominican Republic by province.

<p>A suspected case was defined by the presence of sudden fever and arthralgia. The color scheme classifies provinces by number of total suspected CHIKF cases, determined by summing the number of cases reported in MSP DIGEPI weekly bulletins and Chikungunya Outbreak Bulletins for each epidemiological weeks between February 16, 2014 and June 6, 2015. No exact case numbers were reported to MSP DIGEPI for provinces shaded in white. Number 32, Distrito Nacional, represents the national district, which does not pertain to a province. The city of La Romana and the port of Bajos de Haina, where the outbreak is suspected to have started, are highlighted in red. Map created using Epi Info^TM 7.1.5 software licensed by the Centers for Disease Control and Prevention (<a href="http://wwwn.cdc.gov/epiinfo/7/" target="_blank">http://wwwn.cdc.gov/epiinfo/7/</a>). MSP DIGEPI weekly bulletins publicly available through Minesterio de Salud Publica (<a href="http://digepisalud.gob.do/" target="_blank">http://digepisalud.gob.do/</a>).</p

Distribution of respiratory and gastrointestinal symptoms by age.

<p>Serum from patients visiting an emergency clinic in the DR was tested for CHIKV RNA and IgM, and results were retrospectively matched to clinical features documented by physicians. Children and young adults below the age of 15 were the primary demographic groups presenting with respiratory and gastrointestinal symptoms for both CHIKF(+) (RNA-positive) and CHIKF(-) (both IgM and RNA negative) patients.</p

Clinical diagnoses made for CHIKF-positive and CHIKF-negative patients.

<p>Serum from patients visiting an emergency clinic in the DR was tested for CHIKV RNA and IgM, and results were retrospectively matched to initial diagnoses based on clinical presentation. The most common diagnosis for patients in both groups was undifferentiated febrile illness. Most notably, while CHIKF-positive (RNA-positive) patients (A) were more likely to be diagnosed with something other than CHIKF, no CHIKF-negative (RNA and IgM negative) patients (B) were misdiagnosed with CHIKF.</p

Demographic data for CHIKF(+) and CHIKF(-) patient serum samples collected from patients in La Romana, Dominican Republic July-August 2014, and associated relative risk.

<p>Demographic data for CHIKF(+) and CHIKF(-) patient serum samples collected from patients in La Romana, Dominican Republic July-August 2014, and associated relative risk.</p

Age and gender distribution of patient sample pool.

<p>Serum from patients visiting an emergency clinic in the DR was tested for CHIKV RNA and IgM, and results were retrospectively matched to demographic data. A) The age and gender distribution of CHIKV-RNA positive [CHIKF(+)] and CHIKF(-) (both IgM and RNA negative) patients. The majority of patients were under the age of 50 for both CHIKF(+) and CHIKF(-) groups. B) The age and gender distribution of patients who were hospitalized.</p