In March 2007, a stomatitis outbreak occurred in a group of juvenile orphaned eastern gorillas. Histopathologic examination of lesion biopsies suggested a herpesvirus etiology. Consensus primers amplified a herpesvirus present in a nasal swab with 98% identity to HSV-1 and 94% identity to HSV-2. Further sequence analysis of a 341 nt amplicon demonstrated 100% sequence identity with HSV-1, and 89% for HSV-2. Results are strongly consistent with the presence of HSV-1 in these animals. Results have implications for the potential release of these orphans into the wild.
In June 2009, a respiratory outbreak occurred in Hirwa group (a group of 12 mountain gorillas, habituated for tourism). Two animals, not treated, died: an adult female and a male infant born to a symptomatic mother. The adult female was first observed coughing and lethargic but feeding; four days later she worsened and died a day later. The three-day old infant died without exhibiting clinical signs. Its mother exhibited severe clinical signs for two to three days peripartum. Analysis by PCR revealed human metapneumovirus (HMPV) in multiple tissues, including serum and lung from the adult gorilla, and lung from the infant. Streptococcus pneumoniae and Klebsiella pneumoniae were detected in respiratory tissue of the adult, but not the infant.1 The metapneumovirus was most closely related to a South African strain that had not yet mutated, suggesting recent entry of this virus into the gorilla population. This points to the importance of strict enforcement of human-gorilla proximity rules.
We would like to acknowledge a grant from the David and Lucile Packard Foundation to the Mountain Gorilla One Health Program.
1. Palacios G, Lowenstine L, Cranfield M, Gilardi K, Spelman L, Lukasik-Braum M, et al. Human metapneumovirus infection in wild mountain gorillas, Rwanda. EID. 2011;17(4).