PAINS ASSOCIATED WITH COVID-19 LONG COVID & PERSISTING PAIN
The name corona virus comes from the spikes on the surface of virus (corona - Latin w ord for crown), when seen under the microscope. On 11th March 2020 WHO declared COVID-19 outbreak as global pandemic a and 1 year on we are still haunted by the mysteries of this virus. Much has changed in the world of medicine in the last 1 year including how we look at COVID-19 as more evidence accumulates supporting COVID-19 as acomplex multisystem disease rather than just being restricted to the lungs.
The widespread perception is that if one gets COVID infectionthe possible outcomes include recovery in two to three weeks or hospital admission or death is severe cases. Contrary to this, for some people COVID 19 infection is not a discrete episode lasting a few weeks, but marks the start of a longterm illness with ongoing and often debilitating symptoms. This is addressed as Long COVID and may perhaps be the first illness name to be coined by patients themselves through social media. This diagnosis challenges the clinical and governmental assumptions about COVID and brings more uncertainty into picture.
Persisting pain and fatigue is one of the symptoms seen in Long COVID. This writeup explores the relationship between COVID-19 infection and pain, including the pains related to acute COVID-19 infection and those persisting after the infection as a part of long COVID-19.
PAINS ASSOCIATED WITH ACUTE COVID-19 INFECTION
In the list of COVID -19 infection symptoms muscle pain and fatigue (44%) are not far behind other symptoms such as fever (98%), cough (76%) and dyspnoea (55%). Even the so called mild COVID-19 cases can be troubled by miserable symptoms such as debilitating headaches, body aches and extreme fatigue. Commonly observed pain issues during an acute infection with incidence range as found in different studies are as follows:•
Muscle & Joint pain 1.5 - 61 %
• Headaches1.7 - 33.9% , • Sore throat0.7 – 47.1% • Chest pain1.6 – 17.7%
• Abdominal pain1.9 - 14.5%
Generalise soreness, pain and fatigue are commonly seen with viral infections such as seasonal flu. In COVID-19 pain is described by most as diffuse ache or soreness sensation similar to that one experiences after exercise. These pains are however are not localised to one part of body and take longer to resolve. Some studies have observed more involvement of muscles as compared to joints in the early stages.
Multiple mechanisms are postulated to be possibly contributing to these pains such as virus triggered inflammation, direct muscle damage and blockage of blood vessels by clots leading to the poor blood supply to the muscles etc. The relative contribution of thesefactors remains unknown. Besides these other factors such as stress and low mood may play a role in modulating the pain perceived by an individual.
PERSISTING PAIN AFTER COVID-19 INFECTION
A study conducted in Italy evaluated 143 patients for persisting symptoms, 60 days after the initial onset of COVID-19 symptoms. 87.4% of patients reported persistence of at least 1 symptom with 55% having 3 or more symptoms. Symptoms included fatigue (53.1%), dyspnoea (43.4%), joint pains (27.3%) and chest pains (21.7%). Worsened quality of life was observed among 44.1% of patients.
Another study from China, involving 1733 patients found that six months after discharge 76% of patients had at least one of the these symptomsfatigue/weakness (63%), difficulty sleeping (26%), hair loss (22%), altered smell and taste (11 and 9%), and mobility issues (7%).
These studies highlight the impact of COVID even after the resolution of the acute phase. Other commonly observed symptoms include inability to concentrate, impaired memory, anxiety, depression and sleep disturbances. Persistence of these problems are post-acute-COVID-19 termed as syndrome or "long COVID-19
with as incidence varying between 10- 70 % in different studies. There is uncertainty regarding the underlying mechanisms responsible for Long COVID. Some of the possible causes include a reduced or lack of immune response, relapse or reinfection of the virus, inflammatory and long lasting changes to the immune system, post-traumatic stress and injury to multiple organs.
Joint pains or arthritis after viral infections is not a new phenomenon with viral arthritis responsible for 1% of acute arthritis cases worldwide. In India joint pains after viral infections such as dengue and chikungunya are common. Diagnosis of viral arthritis can be challenging, with early onset within the first weeks of infection.