COVID 19 - Epidemiology and Prevention

1. COVID -19
Epidemiology & Prevention
Dr Rohit Kallukadavil
MBBS, MD, DNB, MRCP Sce (Resp)
Consultant Pulmonologist and Critical care specialist
HGM Hospital, Kottayam, Kerala.

2. Introduction …
• COVID-19 is caused by a novel beta coronavirus, now named SARS-
CoV-2.
• is the seventh Corona virus known to infect humans.
• Was declared a global pandemic by WHO on March 11th 2020.
• Till now there is no specific treatment or vaccinations are available.

3. • Corona virus – can infect humans and animals(cats, bats,
cattles)
• Humans it can cause disease – common cold to
ARDS(SARS,MERS)
• Human infections are - α and β corona viruses.

4. Introduction
• 7 strains can infect humans
1. 229E (α coronavirus)
2. NL63 (α coronavirus)
3. OC43 (β coronavirus)
4. HKU1 (β coronavirus)
5. SARS-CoV (the β coronavirus that causes severe acute respiratory syndrome, or SARS)- 2003
6. MERS-CoV (the β coronavirus that causes Middle East Respiratory Syndrome, or MERS)- 2012
7. SARS-CoV-2 (the novel coronavirus that causes coronavirus disease 2019, or COVID-19)- 2019

5. • Virus causing COVID -1 9 is - severe acute respiratory
syndrome corona virus 2 (SARS-CoV-2), before: 2019-nCoV.

6. Origin ?
• SARS-CoV infected civet cats and infected humans in 2002
• MERS-CoV is found in camels and infected humans in 2012

7. Site of origin?
• Wuhan city of China

8. Wuhan Virology Lab ?

9. TransmissionofCOVID-19
• The primary route for the spread of COVID-19 is thought to be through
aerosolized droplets
• Expelled during coughing, sneezing, or breathing,
• also concerns about possible airborne transmission.
• Faeco-oral transmission has also been reported in a few cases, with viral
isolation from the faeces of some patients

10. Transmission
• Droplets – viruses in respiratory
secretions when cough, sneeze,
talks
• Cough- 3000 droplets
• Sneeze- 40000 droplets
• Droplets travel – nearly 2 m/ 6
feets
• Droplets can enter through
respiratory mucous membranes

11. • Fomites – infected surfaces
• Infection can also occur by touching infected surfaces
followed by eyes, nose, mouth,

12. Persistence of Virus on surfaces
Object Duration
Gloves 8 hours
wood 4 days
steel 2 days
glass 4 days
paper 5 days
Plastic 5 days
Surfaces disinfection
>60% Ethanol
0.5%Hydrogen peroxide solution
0.1%Sodium hypochlorite solution

13. Epidemiology

14. Jan 30- First case in Kerala /India
22/4/20- World: 25 L / 1.7 L deaths
India: 19,984/ 640
Kerala 408/3.

16. EpidemiologyTotal cases: 24.3 L, Total deaths: 1.67 L (April 20th)

17. Affected countries

18. India
17,656 cases, 559 deaths

19. Kerala
Total: 408 cases, deaths: 3

21. Clinical features
• Incubation period- 2 to 14 days, usually 5 days after
exposure
• Case fatality 2.3 to 5%
• More in elderly and males
• 80%- mild to moderate disease
• 13%- severe(Hypoxia, ARDS)
• 6%- critical illness(shock, resp failure, MODS)

22. Symptoms
• Clinical features as per Chinese studies
were
• Fever (83-98%),
• Dry cough (59-82%)*,
• Fatigue (44-70%),
• Anorexia ( 40-84%),
• SOB (31-41%)
• Sputum production (28-33%),
• Myalgia (11-35%) and
• Less common symptoms were sore
throat, diarrhoea, dizziness, anosmia or
ageusia in <10% pts.

24. COVID-19 Vs. FLU Vs. COLD

26. Definitions
• Confirmed case: A person with laboratory confirmation of
COVID-19 infection, irrespective of clinical signs and symptoms.
• Probable case: a suspected case with Test result inconclusive
or testing could not be done
• Covid Suspect:
• A pt with ARI & h/o travel to a location with community
transmission during 14 days prior to symptom onset.
• Or pt with ARI & close contact with COVID pt in last 14 days
• Or a pt with severe ARI in absence of alternative diagnosis

27. Close contact
• Face-to-face contact with a probable or confirmed case
within 1 meter and for more than 15 minutes
• Direct physical contact with a probable or confirmed case
• Direct care for a patient with probable or confirmed COVID-
19 disease without using proper personal protective
equipment

28. Lab findings
• Leucopenia and lymphopenia. Leucocytosis <25%
• Neutrophil/lymphocyte ratio if >3.1- predicts ARDS progression
• PLC can decrease
• SGOT/PT increase
• CRP elevated in 60-86%
• Ferritin elevated (? HLH)
• CXR: Normal – initially, then lobar multilobar consolidation
• CT: ground glass opacities with sub pleural distribution in lower
lobes – in early stages, then crazy paving, consolidations can
worsen

29. Prevention

30. Infectivity of Covid 19
R0- average number of people
that will be infected from a
contagious person.
R0- is not fixed – decreases
with preventive measures.
Common Influenza- 1.3

31. For community

33. How to prevent community transmission
• Lock down, avoid
crowds
• Closure of non
essential services
• Closure of schools
• 6 F – social distancing
• Hand hygeine

34. Non pharmacological interventions to reduce COVID
mortality-Model by Ferguson et al

35. Social distancing saves lives….

36. • Quarantine - separation of individuals who are not yet ill
but have been exposed to COVID-19, have a potential to
become ill.
• Isolation - separation of individuals who are ill, suspected,
or confirmed COVID-19 cases.

37. • During SARS outbreak in 2003 found that washing hands
more than 10 times daily was 55 percent effective in
stopping virus transmission
• while wearing a mask was actually more effective at about
68 percent.
• Hand washing+ Mask+ Gloves – 91% protection.

38. Data -13/4/20

39. Iceland
• No lock down
• 1778 cases with 10 deaths, 1417-recovered
• Banned crowds>20 people
• Closed schools.
• Mainly by Testing and contact tracing
• 50% of population-testing(3.5 L-total population)

40. How China controlled COVID ?
• ? Reliable data
• 11 weeks lock down in Wuhan
• Two specialist corona hospitals in Wuhan
• Strict containment measures.
• AI, mobile app(WeChat) for contact
tracing and travel restriction.
• Availability of PPE, masks etc.
• ?Previous experience with SARS- in
2002(5000 cases/ 500 deaths)

43. • Health care workers are the most important agents in the
fight against COVID -19
• Everything else could be manufactured

44. Hospitals act as amplifying centres for the epidemic
• Hospitals act as amplifying centres for the epidemic- during
SARS and MERS epidemics.
• - need to reduce crowd in hospitals
• - less severe COVID cases should be treated in home or
specific covid care centre.

45. Clinical practice- precautions..
• Doctors and paramedical staff above age of 60 years.
• Those with underlying medical conditions (especially
immunocompromised / predisposing to infections) like: – DM,
CLD, CKD,CAD, Chronic lung conditions like Asthma, COPD,
Bronchectasis, ILD, etc., Cancer, On Chemotherapy or Steroid
treatment, Pregnant, Seropositive status.
• Always consider – every patients as Corona suspect- unless
proved otherwise.
• Always use Mask and Hand hygiene

46. Triage on phone
• The crucial 1st step in protecting doctors and other patients.
• All patients must be assessed for possible COVID-19 infection.
• Ask for contact or travel history- before appointment- at registration area.
• If any patient seems to be Covid suspect, please refer him to the nearby
Covid testing centre.
• Avoid routine follow ups, elective procedures
• Guide the patient on phone for minor issues at your discretion

47. Triage at clinic/ Hospital, if possible…
• Patients with Fever, cough or dyspnoea should be evaluated in a
separate area- ? Fever clinic
• Triage stations with adequately trained staff should be allotted at the
entrance of each health care facility.
• Give Tripple layer mask to suspected pt.
• Keep 1 meter distance from pt.
• Allot dedicated equipments like steth, gloves etc.
• Use of Personal Protective Equipments (PPE) is preferred.
• Perform hand hygeine.

48. Clinic management…
• Restrict the OPD time to limited hours
• Avoid walk-in patients
• Avoid relatives in OPD as much as possible
• Make the patients sit about 1 meter apart
• Keep windows and doors open
• Avoid A/c
• If patient need to be examined on bed or table, clean it immediately
following the examination.

49. Clinic management…
• The doctor should wear a surgical mask and scrub hands with soap and water and use an alcohol-
based disinfectant after each patient interaction.
• Minimize fomites on table or in clinic- including curtains, mobiles etc.
• Avoid multiple staff attending OPD, allot dedicated staff to each OPD.
• Keep waiting room chairs placed 6 feet apart.
Decontamination:
•1. High touch surfaces: Disinfection of high touch surfaces like (doorknobs, telephone, call bells,
bedrails, stair rails, light switches, wall areas around the toilet) should be done every 3-4 hours.
•2. Low-touch surfaces: For Low-touch surfaces (walls, mirrors, etc.) mopping should be done at
least once daily.

50. Display in Clinics…
• Visual alerts should be posted at the entrance and strategic areas
(waiting areas, elevators and cafeterias)
• To reinforce both patients and health care workers, the importance
of hand hygiene, respiratory hygiene and cough etiquette

51. Hand hygiene…
• All health care workers should perform hand hygiene using alcohol-based hand
rub (20 s)or by washing with soap and water (minimum 40 seconds).
• If hands are visibly soiled, use soap and water for hand wash.
• Avoid touching face mask, eyes, nose, face before hand washing.
• Foot operated sanitizers should be put outside elevators, OPDs, screening
areas, ICUs and wards.
• Sanitize following: Computer keyboard and mouse, House and car keys, Re-usable
water bottles, Car steering wheel, Door handles

53. How hand hygiene works ?
• Water helps in rinse of nanoparticles like dirt
and viruses out of crevices which make up our
finger prints
• COVID has lipid membrane- damaged with soap
molecules.
• Hydrophobic tail bond with viruses and dirt and
hydrophilic part bond with water and get
washed away.
• Alcohol break the lipid membrane

54. Need of the protective gears for all?
• Hand hygiene is for all healthcare workers
• Based upon your role in patient management and duration of
exposure with patient (more than or less than 15 minutes), you have
to donn the protective gears.
• Thus, need of protective gears depends upon the place where you are
practicing

55. • Aerosol generating procedure- Intubation, suctioning,NIV,
CPR, Bronchoscopy, Neb, specimen collection) –Use full PPE
with N95 mask.
• COVID ICU,OT,Ward – Full PPE with N95
• Non covid ward- 3 ply surgical mask
• All other areas of hospital- with less chance of COVID- use 3
ply mask.

56. Mask
American standard –by NIOSH – N 95%
Europestandrad- FFP2- Filtering face piece score 2

57. Mask etiquette…
Increase in risk of transmission associated with the incorrect use and disposal of
masks.
i. Place mask carefully to cover mouth and nose and tie securely to minimize any gaps
between the face and the mask
ii. While in use, avoid touching the mask
iii. Remove the mask by using appropriate technique (i.e. do not touch the front but remove
the lace from behind)
iv. After removal or whenever you inadvertently touch a used mask, clean hands by using an
alcohol-based hand rub for 20 seconds or soap and water if visibly soiled for 40 seconds
v. Replace masks with a new one as soon as they become damp/humid
vi. Do not re-use single-use masks
vii.Discard single-use masks after each use and dispose-off them immediately upon removal
viii.For N95 respirators(can use for 8 Hr) - fit check must be performed after wearing.

60. TRANSPORT PROTOCOL
For shifting any suspected or confirmed COVID-19 patients, the following steps
must be followed by the accompanying healthcare provider:
A. Decontaminate hands (alcohol-based sanitiser/soap)
B. Don PPE
C. Inform Trauma Centre control room regarding the admission/transfer
of a potentially infectious patient.
D. In ambulance
• Use single use or single patient use medical equipment where possible
• Use disposable linen if available
• Monitor and document vitals and medical management done in
ambulance

61. Environmental sanitation:
• Immediately remove and wash clothes and bedding that have blood, stool or other
body fluids on them
• Clean and disinfect frequently touched surfaces in the quarantined person’s room
(e.g. bed frames, tables etc.) daily with Sodium Hypochlorite solution (1%) or
ordinary bleach (5%)
• Clean and disinfect toilet surfaces daily with regular household bleach
solution/phenolic disinfectants
• Wash laundry used by the person separately using common household detergent
and dry thoroughly
• Place all used disposable gloves, masks and other contaminated waste in a lined
container before disposing

62. Special precautions to be followed for aerosol generating
procedures
• Include tracheal intubation, non-invasive ventilation, tracheostomy,
cardiopulmonary resuscitation, and bronchoscopy.
• Are all associated with increased risk of transmission of
• COVID-19
• HCWs conducting such procedures should be wearing full-body PPEs
including N95 particle-filtering masks
• Should be carried out in an adequately ventilated room or in airborne
infection isolation rooms (AIIR) which are negative pressure rooms

63. Emotional needs of HCWs
• Must not be ignored
• HCW at front-line are under extreme physical and mental stress.
• They are physically overworked, forced to make tormenting triage
decisions, upset by guilt and pain from losing patients and colleagues.
• Worrying about their own health and the constant anxiety of passing
infection on to their families.
• China- 70% stress, 50% depression, 44% anxiety, 34% insomnia.

64. For all medical professionals (Important points…)
Social distancing poorly practiced in hospitals, so please pay attention
• Keep 1 m distance always
• No elective job at hospital
• Clean your desk, door knob, computer, workstation yourself or in your presence
• Keep door opens
• Minimal touching
• Do not touch papers and files, prefer Electronic entries, if feasible
• Wash hands after every patient examination and clean your instruments with
sterilium, especially stethoscope to avoid cross infection
• Avoid lifts, Closed space, Don’t touch lift buttons. Get them cleaned often
• Avoid Heavy load at clinic
• Leave all your stethoscope, knee hammers and other medical stuff in hospital
itself. Don't take home
• Decontaminate car handles

65. • Use only 1 pen, phone and water bottle (disposablebetter)
• Decontaminatephone
• No watches no rings no bangles no dangling earrings
• Hairs tied and Cover your head with cap.
• Shift to scrubs full sleeves, if available.
• Empty bowel and bladder before you wear your PPE
• Wear double glove, goggle, foot covers
• Keep your palms together when you see patients to remind you not to
touch them.
• Better don't use stethoscope. These are not normal times
WhileonPPE(Improtant points…)

66. Boost your Immunity
• Good food, plenty of oral fluid intakes, fruits and vegetables
• Sleep- 7-8 hours
• Regular exercise
• Vaccinations ????

67. ICMR recommendation for COVID-19 Use of
hydroxy-chloroquine for prophylaxis for selected individuals as follows
• Asymptomatic healthcare workers involved in the care of
suspected or confirmed cases of COVID-19:
– 400 mg BD- Day 1, then 400 mg once weekly x next 7 weeks
• Asymptomatic household contacts
– 400 mg BD - Day 1, then 400 mg once weekly for x 3 weeks
Contraindications: QTc>500msec, Porphyria, Myasthenia, Retinopathy, Epilepsy.

68. Evidence
• Cause Increase Ph of endosome and prevents virus entry,
transport and post entry events ?
• invitro action- chloroquine/ hcq against viruses- corona/
influenzea
• No peer reviewed publications/ well conducted RCT.
• Unpublished study from China and France(HCQ+
Azithromycin) – showed better viral clearance.

69. Thank you