A 25-year-old man was infected with COVID-19 twice and developed more severe symptoms the second time around, according to a new case study published in the medical journal The Lancet.
The man first tested positive for coronavirus on April 18, 2020, and then again on June 5, 2020, with genetic analysis of the virus showing significant differences between the “variant” associated with the infection, scientists in Nevada said.
The 25-year-old from the US first presented virus symptoms of sore throat, cough, headache, nausea, and diarrhoea in late March but recovered by the end of April.
He felt better until the end of May and even tested negative twice for the virus that month.
But in late May, he went to an urgent care centre with similar virus symptoms and five days later, he experienced low oxygen levels and shortness of breath.
He was treated at the accident and emergency department where a chest x-ray showed that he had developed pneumonia.
“The patient required ongoing oxygen support in hospital and reported symptoms that included myalgia [muscle pain], cough, and shortness of breath,” the researchers said.
This is the first individual in North America who appears to have been reinfected with the virus and he joins a mere handful of cases globally.
Individuals who have been reinfected with the virus had previously emerged in Belgium, Hong Kong and the Netherlands.
Only one other patient, a person in Ecuador, appears to have developed more severe symptoms the second time around, scientists wrote in The Lancet.
It remains unknown how long people who have contracted COVID-19 are immune although many experts have said that they are likely immune for a certain period of time.
An encouraging study in Iceland showed that antibodies that help humans fight off the virus likely last for at least four months and do not fade quickly.
This is encouraging for vaccine efforts which will attempt to trigger that immune response in humans to protect them from the virus.