BENGALURU: One to two per cent of Covid patients develop a fever about 14 days after they are given a clean bill of health, puzzling doctors as there is no clear cause.Called post viremic pyrexia (fever that occurs after the phase in which a virus multiplies in the body), the fever lasts 4-5 days and has been seen in all categories of patients.“Usually, fever is indicative of an underlying infection. But when we do blood and urine tests, the results indicate there is no secondary infection, meaning it is not an infective fever. As it occurs 14 days after the Covid infection, it has no connection with the multiplication of the Covid-19 virus in the body,” said Dr Anoop Amarnath, head of the scientific board at Manipal Hospital and member of the state Critical Care Support Team.
“We don’t know the exact cause. It could be due to remnants of the virus or remnants of the cytokine storm in the body,” Dr Amarnath said. A cytokine storm refers to the body’s immune response to a disease, infection, or autoimmune condition, in which the body releases cytokines (proteins) into the blood. Another reason could be the virus shedding 45-50 days after the infection, leading to a low fever and low oxygen levels. Patients are prescribed remdesivir and steroids, said Dr Ravindra Mehta, head of pulmonology at Apollo Speciality Hospitals.
“We check for inflammatory markers and infections such as typhoid, dengue, malaria and flu. The RT-PCR test is done again. These fevers are not bad and don’t create a major problem and are not something the public should worry about,” Dr Mehta said, adding that paracetamol up to 3-4gm per day is sufficient to reduce the fever.
In the elderly, it could be due to age-related changes in the immune system, due to which the body only partially tackles Covid-19, and part of the infection continues, causing fever.“Usually, such patients are treated as outpatients. The fever is due to the inflammatory pathology triggered by the virus. Escalating levels of cytokines cause inflammation, leading to fever. It generally settles down, and can be cured with time, diet and medication,” said Dr Srivatsa Lokeshwaran, consultant of interventional pulmonology at Aster CMI Hospital.