Headache refers to the pain within the head or upper neck. Globally, the prevalence of general population is 47% and therefore the lifetime prevalence is 66%.23 for the same. Headache is a burden to society with reduced quality of life and disability. Headache is additionally a really common clinical symptom, and therefore the infection with the COVID-19 isn’t an exception. Among many pain symptoms in Covid and Long Covid During a recent retrospective case study, during which Guan et al analyzed data from 1590 patients with COVID-19 in China between 11 December 2019 and 31 January 2020, the incidence of headache was 15.4%. In a study 205 patients complained of headaches among the 1328 patients. Up to April 12, 2020, supported the 11th epidemiological report issued by COVID-19 National Incident Room Surveillance Team, 6394 confirmed cases were reported in Australia, during which 36% reported headache (n = 2010). Some patients also presented neurological symptoms, like dizziness, nausea, and vomiting along with headache.
Reason of headache in Covid
The mechanism of COVID-19-induced headache remains unclear. Following are some some possible reasons:
- The amount of cytokines within the serum of patients with COVID-19 were elevated, including tumor necrosis factor, interleukin 2, and granulocyte macrophage-colony stimulating factor. These cytokines in response to viral infections may cause headache.
- When SARS-CoV-2 invades lung tissue, it’s going to cause alveolar gas exchange disorders, resulting in hypoxia within the brain, increasing the anaerobic metabolism of mitochondria in nerve cell and accumulation of acid metabolites. it’ll cause obstruction of cerebral blood flow, swelling of brain cells, cerebrovascular dilatation and headache due to ischemia and congestion.
- Headache may result from the direct invasion of SARS-CoV-2 into the systema nervosum.
- The most routes of COVID-19 transmission among people are close contact and droplet contagion. The trigeminal or the solitary tract is infected thanks to the contact of the attention conjunctiva or tongue taste buds with droplets containing SARS-CoV-2, the virus can infect the central systema nervosum (CNS) through retrograde traveling. because the respiratory droplets containing SARS-CoV-2 reach the nasal mucosa, the virus may directly infect olfactory sensory neurons then enter the brain from nervii olfactorii .
- During a transgenic mouse model of human angiotensin converting enzyme 2 (ACE2) infected by SARS-CoV, the nervii olfactorii was the route for the virus to enter and infect the CNS; however, there have been still many infection sites indirectly connected to the neural structure , indicating liquid body substance pathway for virus infection (such as blood, lymph and cerebral spinal fluid). SARS-CoV-2 has an equivalent functional receptor as SARS-CoV – ACE2.
- The many presence of blood and lymphatic capillaries within the nasal mucosa provides a positive environment for the virus invasion and help to enter the blood stream after interaction with ACE2 expressed on endothelial cells. When the virus spreads within the tract, it also can bind to ACE2 expressed on the epithelial cells and enter the blood stream. SARS-CoV-2 can spread to the CNS through vascular pathways. Likewise, the virus within the GI tract also can enter the CNS through cranial nerve like Vagus, blood vessels and lymphatic pathways.
Importance of headache in Covid patients:
Headache isn’t the commonest symptom of patients with COVID-19, fever is the commonest symptom, but headache must not be ignored. A confirmed case reported that he only experienced strong headache and fatigue, without fever, coughing or breathing problems. Then, he displayed anosmia and slowly emerged common symptoms. This condition indicates that headache and anosmia are the first signs of COVID-19 in some patients.
What to do with headache?
- Must not be over anxious, headache is common with any viral infection and resolves spontaneously.
- Take rest, sometimes take paracetamol
- If headache persists, or increase or associated with neurological symptoms like numbness, weakness, convulsions, visual problems the patient must consult a doctor.
- Headache & Pain management in Covid patients is challenging.
- Weng LM, Su X, Wang XQ. Pain Symptoms in Patients with Coronavirus Disease (COVID-19): A Literature Review. J Pain Res. 2021;14:147-159
- Guan WJ, Liang WH, Zhao Y, et al. Comorbidity and its impact on 1590 patients with Covid-19 in China: a nationwide analysis. Eur Respir J. 2020;55:2000547
- Neurath MF. Covid-19 and immunomodulation in IBD. Gut. 2020;69:1335–1342