Fig 1.
Map of Grand Cayman, Cayman Islands.
Red foci represent confirmed Helicobacter positive cases. The Queen Elizabeth II Botanic Park (QEIIBP), where all positive Grand Cayman blue iguanas were found, is encircled by the dashed line in the right inset. The cluster of cases in the north of the QEIIBP is in and around the breeding facility. The West Bay region in the upper left inset is where confirmed Helicobacter positive cases in green iguanas were found and the red star in the southwest indicates the George Town location of additional green iguana mortalities not confirmed to be Helicobacter positive. Green regions in the main map represent protected areas and blue is inland water. Created by the Department of Environment, Cayman Islands Government. 2006 Quickbird satellite imagery courtesy of the Department of Environment, Cayman Islands Government.
Table 1.
Summary of cases included in this report.
Fig 2.
Queen Elizabeth II Botanic Park daily precipitation.
Precipitation measurements in mm (green bars) for the April-October periods for a) 2015 and b) 2016. Dates of Grand Cayman blue iguana onset of signs attributed to Helicobacter infection or dates Helicobacter positive specimens were found deceased are designated by red lines. For the ease of visualization, presented are the precipitation measurements bracketing the time period when the Helicobacter-related mortalities occurred.
Fig 3.
Grand Cayman—Owen Roberts Airport annual and decadal precipitation anomalies 1976–2019.
Precipitation shown as 365-day totals compared to the annual mean (1,406 mm). Dashed line indicates 6th order polynomial trend showing ~28-year periodic oscillations in annual mean rainfall with an amplitude of 430 mm. Dates of Grand Cayman blue iguana confirmed Helicobacter infections in 2015–16 are indicated along the timeline.
Fig 4.
Grand Cayman blue iguana peripheral blood smear revealing abundant intra- and extracellular spiral-shaped bacteria.
Bacteria were identified as Helicobacter sp. GCBI1 via molecular techniques. Arrows highlight the intracellular organisms within monocyte cytoplasm. Studbook No. 786. Modified Wright-Giemsa stain (“Dip Quick”), 1000x original magnification with oil immersion.
Table 2.
Hematology results for three Helicobacter sp. GCBI1 positive Grand Cayman blue iguanas.
Table 3.
Biochemical assay and peripheral blood smear results for nine Helicobacter sp. GCBI1 positive Grand Cayman blue iguanas.
Fig 5.
Abundant argyrophilic spiral-shaped bacteria in the heart of a Grand Cayman blue iguana.
Bacteria are present in the cardiac tissue of otherwise normal heart. Arrows highlight some of the spiral-shaped organisms. Studbook No. 1278. Silver stain, original magnification 1000x with oil immersion.
Fig 6.
Molecular analysis of Helicobacter sp. GCBI1.
A. Rooted phylogenetic tree of Helicobacter 16S rRNA nucleotide sequences, with local support values shown at the branch points. GenBank accession numbers are shown. Helicobacter sp. GCBI1 is shown in red. Other reptilian Helicobacter species are presented in blue. B. DNA sequence alignment showing primer and probe binding sites for qPCR assay targeting Helicobacter sp. GCBI1.