1. COVID-19
Written and published by
Elaheh Kordzadeh-Kermani
Hossein Khalili
& Iman Karimzadeh
Presented by Saba Idrees
From MS Microbiology.
2.
3. Introduction
• In December 2019, a novel coronavirus (initially
named 2019-nCov) emerged in Wuhan, China, causing
an outbreak of viral pneumonia.
• Later named SARS-CoV-2 due to structural similarities
with SARS-CoV(2003 outbreak).
• Rapid global spread, with significant morbidity and
mortality.
• Presentation aims to review clinical characteristics,
pathogenesis, and ongoing research efforts.
4. Key Facts and Figures
• As of July 22, 2020:
• Over 14.9 million confirmed cases worldwide.
• More than 610,000 deaths attributed to COVID-19.
• Rapid spread across continents, raising global concern.
• Human-to-human transmission via respiratory
droplets, aerosols, direct contact, and possibly fecal-
oral route.
5. Clinical Manifestations and
Complications
• Common symptoms: fever, cough, fatigue, anorexia,
dyspnea, myalgia.
• Atypical presentations: lack of fever, radiological
abnormalities
• Asymptomatic carriers facilitate transmission.
• Complications: respiratory system involvement
(ARDS), cardiovascular impact (hypertension, heart
disease), and more.
6. Pathogenesis and Mechanisms
• ACE 2 receptor: key for viral entry into host cells.
• SARS-CoV-2 binds ACE 2 receptors with higher
affinity than SARS-CoV.
• ACE 2/angiotensin (1–7) axis disturbance linked to
clinical features
• Evidence of ACE 2 expression correlation with
age, sex, and organ involvement.
• Other potential entry routes: CD 147 receptors,
ongoing research.
7. Ongoing Research and
Management Strategies
• Ongoing efforts to develop vaccines: adenovirus-
based, mRNA-based, and ChAdOx1 vaccine trials.
• Therapeutic approaches: initial use of chloroquine,
hydroxychloroquine; remdesivir's controversial
efficacy.
• Clinical manifestations influencing outcomes: age,
comorbidities, immunosuppressive therapies.
• Further research crucial for improved treatment
and prevention strategies.
8. Neurological Involvement
• COVID-19 has shown to have neurological effects,
including anosmia (loss of smell) and ageusia (loss of
taste).
• Some patients experience neurological symptoms like
headaches, dizziness, and confusion.
• Reports of more severe neurological complications
like encephalitis and Guillain-Barré syndrome have
also emerged.
9.
10. Respiratory Implications
• Severe cases of COVID-19 often lead to acute
respiratory distress syndrome (ARDS).
• ARDS results from an excessive immune response
leading to lung inflammation and fluid accumulation.
• Mechanical ventilation is often required to manage
severe respiratory distress.
11.
12. Gastrointestinal Involvement
• Digestive symptoms such as nausea, vomiting, and
diarrhea have been reported.
• ACE 2 receptors in the gastrointestinal tract may
facilitate viral entry and replication.
• Gastrointestinal symptoms can occur before or in the
absence of respiratory symptoms.
13. Ophthalmic Implications
• Conjunctivitis (pink eye) has been observed in
some COVID-19 patients.
• Although ocular transmission is possible,
respiratory droplets remain the primary mode of
infection.
• Proper eye hygiene is advised to reduce potential
transmission through the eyes.
14.
15. Psychological Impact
• COVID-19 has led to increased stress, anxiety, and
depression globally.
• Social isolation, uncertainty, and fear of the virus
contribute to psychological distress.
• Healthcare providers and vulnerable populations are
particularly susceptible to psychological strain.
16. Reproductive System
• Limited evidence on the impact of COVID-19 on the
reproductive system.
• Concerns exist about potential effects on fertility and
pregnancy outcomes.
• Research is ongoing to understand the virus's impact
on reproductive health.
17. Long COVID
• Some individuals experience persistent symptoms long
after recovering from acute COVID-19.
• Symptoms include fatigue, shortness of breath,
cognitive issues, and more.
• Long COVID's exact mechanism and management are
still being studied.
18. Pediatric Implications
• Children usually experience milder symptoms
compared to adults.
• Multisystem Inflammatory Syndrome in Children
(MIS-C) is a rare but severe complication linked to
COVID-19.
• Pediatric patients require careful monitoring and
follow-up to detect any long-term effects.
19. Vaccination and Immunity
• COVID-19 vaccines have been developed to provide
immunity against the virus.
• Vaccination efforts aim to reduce severe cases,
hospitalizations, and deaths.
• Variants of the virus may impact vaccine effectiveness
and require ongoing research.
20. Public Health Measures
• Preventive measures like mask-wearing, hand hygiene,
and social distancing remain crucial.
• Public health campaigns promote vaccination and
adherence to guidelines.
• Global collaboration and research continue to inform
strategies for pandemic control.
21. Reproductive System & COVID-
19
• Limited data on COVID-19's effects on pregnancy.
• Increased risk of miscarriage, preterm delivery, and
growth restriction.
• Observations of preeclampsia-like symptoms.
• ACE 2 receptors in reproductive tissues might
facilitate viral entry.
22. Gastrointestinal Involvement
• 2-10% of COVID-19 patients experience GI
symptoms.
• Diarrhea and vomiting as initial presentations.
• ACE 2 receptors in GI tract epithelial cells.
• Viral invasion and disturbance in RAS system linked
to GI symptoms.
23. Neuromuscular Complications
• Neurological symptoms in 36% of COVID-19
patients.
• CNS symptoms linked to olfactory bulb route.
• Skeletal muscle injury in severe cases.
• Rhabdomyolysis and Guillain-Barre syndrome
reported.
24. Central Nervous System
Impact
• 88% of severe cases display neurologic
manifestations.
• Neuroinvasive potential of SARS-CoV-2.
• CNS entry through systemic circulation or
neuronal pathway.
• COVID-19-associated acute ischemic stroke
reported.
25. Ocular Involvement
• SARS-CoV detected in tear samples.
• Possible conjunctivitis via droplet inoculation.
• Ocular symptoms in 2-32% of cases.
• Conjunctival swabs positive for SARS-CoV-2.
26. Skin Involvement
• Cutaneous changes less common.
• Skin conditions related to protective measures.
• Reports of skin rash with petechiae.
• Erythematous rash, urticaria, and vesicles observed.
27. Multiorgan Failure
• Dysregulated immune response in CRS.
• Multiorgan failure, respiratory, and heart failure.
• Secondary hemophagocytic lymphohistiocytosis
(sHLH).
• Cytokine elevation and cytopenia in PIMS-TS.
28.
29. Kawasaki-like Syndrome
• Kawasaki-like syndrome in pediatric patients.
• Named Pediatric Inflammatory Multisystem Syndrome
Temporally associated with SARS-CoV-2 (PIMS-TS)
and Multisystem Inflammatory Syndrome in children
(MIS-C).
• Hyper inflammatory syndrome with various
symptoms.
• Link to antibody-dependent enhancement and hyper
stimulated cytokine release.
30. Conclusion & Future Perspectives
• Respiratory system most commonly affected.
• Other systems involved with varying severity.
• Electrolyte imbalances and inflammatory markers
predict outcomes.
• ACE 2 receptor role and mutation concerns.
• Immune dysregulation and possible interventions.
31. References
• 1. Zhou P, Yang X-L, Wang X-G et al. A pneumonia outbreak
associated with a new coronavirus of probable bat origin. Nature
579(7798), 270–273 (2020).
• 2. World Health Organization. Coronavirus disease 2019 (COVID-19)
situation report. (2020).
http://www.who.int/Docs/DefaultSource/Coronaviruse/Situation-
Reports/20200402-Sitrep-73-Covid-19.Pdf?Sfvrsn=5ae25bc7
4%20CDC-SRaF
• 3. Xiao F, Tang M, Zheng X, Liu Y, Li X, Shan H. Evidence for
gastrointestinal infection of SARS-CoV-2. Gastroenterology 158(6),
1831–1833. e1833 (2020).
• 4. Centers for disease control and prevention. Symptoms of
coronavirus. (2020). http://www.cdc.gov/coronavirus/2019-
ncov/symptoms-testing/symptoms.html
• 5. Guan W-J, Ni Z-Y, Hu Y et al. Clinical characteristics of coronavirus
disease 2019 in China. N. Engl. J. Med. 382(18), 1708–1720 (2020).
