Isaac Cary received the Johnson & Johnson COVID-19 vaccine in March but began exhibiting coronavirus symptoms in June. Cary initially thought he was suffering from allergies but noted he was exposed to someone who had tested positive for the delta strain, Fox 29 reported.
The 64-year-old is now in the ICU of the Baylor Scott and White campus in Temple struggling to fight off the disease.
Last week, Johnson & Johnson touted the efficiency of its COVID-19 vaccine against variants, including the delta strain.
In a statement, the company wrote the vaccine demonstrated "strong, persistent activity against the rapidly spreading Delta variant and other highly prevalent SARS-CoV-2 viral variants." The statement also noted that the vaccine's immune response lasts at least eight months.
None of the COVID-19 vaccines are 100 percent effective against the coronavirus.