Prolonged viral shedding in an immunocompetent patient with COVID-19

Discussion

To our knowledge this case is the longest reported duration of viral shedding in COVID-19 in an immunocompetent patient. While the majority of patients infected with SARS-CoV-2 suffer only a mild illness, a significant proportion of patients require admission for supplementary oxygen therapy. Of those hospitalised, 17% become critically unwell and a have mean duration of viral shedding of 20 days.3 Patients who are immunocompromised or immunodeficient experience a prolonged period of viral shedding in other respiratory viral infections4 5 but experience in COVID-19 is more limited. A recent case series in renal transplant suggest that this is also the case in SARS-CoV-2,6 7 and other individual case reports have detailed patients with a prolonged viral shedding.8 9 These cases have been complicated by treatment with immunomodulatory agents during the acute infection. At the time of admission of our patient, the role of steroids in the acute treatment of COVID-19 remained controversial as there were concerns about the effect of such medications on the duration of viral shedding.10 It remains possible therefore that these early treatments adversely effected shedding time. Our patient received no immunosuppressive medications at any point in her illness. Preliminary findings from the Recovery Trial have shown a proven benefit in hospitalised patients with COVID-19 that require supplementary oxygen or mechanical ventilatory support, with a lowering of 28-day mortality, and lowering of duration of hospital admission.11 This was not known at the time of the patient’s treatment and would have formed the standard of care. We could find no clear reason to explain the prolonged period of viral shedding in this patient. Although the presence of a tracheostomy was unusual, we found no published evidence of an increased duration for COVID-19 or other viral infections in the literature. The immune response to SARS-CoV-2 remains poorly understood, it remains credible that differing host immunotypes may play a part in the wide spectrum and duration of disease seen in cases of COVID-19.12

It is well understood that positive PCR tests do not necessarily equate to evidence of viable virus, but the relationship between prolonged shedding and infectiousness remains unclear. Recent cohort studies on nasopharyngeal samples in SARS-CoV-2 suggest the highest viral load is found in the presymptomatic period of infection, peaking at 0.7 days prior to symptom onset and significantly reducing by day 7.13 Viral culture studies found that viable virus is not present in throat swabs beyond day 8 of symptoms despite high viral PCR loads on swabs.14–16 These are small sample studies of well middle-aged individuals and it is difficult to interpret if this is true in all populations.

Our patient’s case was complicated by the presence of her tracheostomy from which viral swabs were taken. It is not clear whether viral shedding in COVID-19 is prolonged in patients with tracheostomy, however such samples are likely to constitute sampling from deeper parts of respiratory tract where samples are more likely to be PCR-positive than nasopharyngeal swabs.15 17 The use of such data on interpretation of infectivity of a patient remains difficult. Issues with sensitivity of viral culture processes as well as an understanding that the number of viable virions needed for infection in vivo is likely to be lower than in vitro has hampered the interpretation of duration of infectivity.18

Prolonged swab positivity in our patient and repeated suctioning of her tracheal secretions had significant implications on our patient’s care. Due to the limited data available at the time surrounding the infectiousness of this patient, it was felt necessary for staff to wear full PPE to enter her negative pressure room. Prolonged isolation and limited contact with the healthcare team, and isolation from her family significantly impacted her mood, nutrition, mobility and psychological well-being. Greater certainty on the viability of viral material in patients with prolonged shedding would have mitigated many challenges in our patient’s care. Relaxation of her isolation and reduced PPE requirements of attending staff and even visiting family would have facilitated earlier and enhanced multidisciplinary care.

Delirium in the context of COVID-19 is well documented and there is a need for realistic solutions that optimise patient care, while mitigating against the risk of transmission.19 Traditional approaches to delirium management were severely impaired by the limitations enforced by full PPE usage for tracheostomy care.

Our patient also reported significant ongoing psychological distress after discharge. There are currently limited data on the psychological impact for patients of the COVID-19 pandemic, but experience from similar coronavirus outbreaks seen with Severe Acute Respiratory Syndrome (SARS) in SARS-CoV-1 virus and Middle East Respiratory Syndrome (MERS) in MERS-CoV virus suggest significantly increased rates of anxiety and depression in survivors,20 21 while a significant proportion of patients develop post-traumatic stress disorder (PTSD).22 Isolation during the epidemics alone was also associated with PTSD and anxiety, with increased duration of isolation increasing risk.23 There is a complex interplay between COVID-19 disease, isolation and mental health, and we need to better understand causation and mitigate its effect.

We report a case of prolonged viral shedding in a patient with COVID-19. This case provides evidence that immunocompetent individuals may have a prolonged period of viral shedding. There is a need to understand the risk of transmission in such patients, as this has significant implications on an individual’s mental health and the wider public health advice. We demonstrate the complexities of managing patients isolated for prolonged periods and the need for emergent strategies to minimise their impact of current and future mental health.